AN EVALUATION OF UQUiD DAIRY
MANURE TREATMENTS BY 810LOGICAL,
CHEWCAL AND ORGANOLEPTEC
TECHNIQUES

Thesis for the Degree of M, S.
MECHSGAN S‘ME UNiVERSlTY
CHARLES C. SIALUNGS

1976 ‘

 

IIIIIIIIIIIIIIIIIIIIIIIIIII

3 1293 10649

 

LIBRARY

Michigan State
University

 

 

 

 

ABSTRACT
AN EVALUATION OF LIQUID DAIRY MANURE

TREATMENTS BY BIOLOGICAL, CHEMICAL
AND ORGANOLEPTIC TECHNIQUES

BY
Charles C. Stallings

Various compounds have been added to manure to
prevent the formation or release of malodors. Under dif-
ferent conditions inconsistent results have been recorded.
The source (species) of manure appears to play a dominant
role in efficacy of the compound added. This study was
designed to test various compounds now in use plus some
others using fresh and decomposed liquid dairy manure.

In Experiment I fresh liquid dairy manure (13
percent dry matter) was treated with paraformaldehyde
(7000; 10,000; 30,000 PPM), acrolein (l and 100 PPM),

H P04 (657; 1000; 10,000 PPM), NaClO4 (250; 500; 2000 PPM),

3

H202 (75; 150; 300 PPM) or KMnO4 (250; 500; 1000 PPM).

Paraformaldehyde at 7000 and 30,000 PPM markedly reduced
microbial counts below control values for 22 days. H3PO4

at 10,000 PPM and NaClO at 2000 PPM slightly reduced

4
microbial counts at day one and eight, but by day 15 values

Charles C. Stallings

were similar to control. H3PO4

counts at eight and 15 days.

at 65? PPM slightly reduced

The pH of paraformaldehyde and H3PO4 treated manure
tended to be below those of control manure. The pH was
inversely related to treatment concentration. The group
mean for NaClO4 treated manure was lower than pH from
control manure but pH was not inversely related to treat-
ment concentration. These changes in pH should not be
extreme enough to cause problems when added to the soil.

Two days after addition of paraformaldehyde to
manure concentration of ammonia in the air space over fresh
manure was lower than control (p < .05). This trend con-
tinued for the duration of the experiment (21 days) indi-
cating decreased decomposition and odor production. At day
seven 2000 PPM NaClO4 treated manure had greater concen-
trations than the two lower treatment concentrations
(p < .005).

Fresh manure treated with paraformaldehyde at 7000
and 10,000 PPM reduced odor offensiveness to below "faint
offensiveness" compared to control at approximately
"definite offensiveness." Similarly odor strength was
reduced. KMnO4 at 1000 PPM reduced offensiveness to just
above "faint offensiveness" compared to control at above
"definite offensiveness."

In Experiment II decomposed liquid dairy manure

(one percent dry matter) was treated with lime (5000 and

Charles C. Stallings

10,000 PPM), paraformaldehyde (1000; 5000; 10,000 PPM),
H202 (100 and 500 PPM) or KMnO4 (500 and 1000 PPM). Lime
and KMnO4 increased pH above control manure. Paraformalde-
hyde tended to decrease pH.

Offensiveness ratings at day one were reduced by
500 PPM H202 and 500 and 1000 PPM KMnO4 to below "faint
offensiveness" compared to control at approximately "strong
offensiveness."

The same additives were evaluated in Experiment III
and Experiment II. Dry matter of the partially decomposed
liquid dairy manure used in Experiment III averaged 5.6
percent. Microbial numbers were not reduced at day one,
but by day eight paraformaldehyde reduced counts. Microbial
numbers were inversely related to treatment concentration.

As in Experiment II, pH's of lime and KMnO4
treated manures were greater than control. Paraformaldehyde
treated manure tended to be lower than control. These pH
changes would probably not cause problems in the soil.

Lime treated manure had higher total ammonia (NH3
and NH4+) concentrations than control manure (p < .05) at
day four. At day 11 paraformaldehyde treated manure had
total ammonia concentrations lower than control (p < .005).
Total ammonia concentration was inversely related to
treatment concentration.

Offensiveness ratings were inconsistent, but KMnO

4
tended to reduce odor offensiveness below that of control

Charles C. Stallings

at all three periods evaluated, although not below the
"faintly offensive" rating.

Experiment IV, using decomposed liquid dairy manure
(4.7 percent dry matter), evaluated paraformaldehyde
(5000 vs. 10,000 PPM), H202 (100 vs. 500 PPM) and KMnO4
(500 vs. 1000 PPM) to determine which treatment concen-
tration to test further. Paraformaldehyde (5000 PPM),
H202 (500 PPM) and KMnO4 (500 PPM) were chosen and used to
compare treatments against themselves. Paraformaldehyde
did not decrease offensiveness in decomposed manure and
possibly increased it. H202 decreased offensiveness con-
sistently at 0.5 and 1.5 hours after addition possibly up
to 30 to 32 hours. These results were complicated by
foaming. KMnO4 reduced offensiveness possibly within six
to eight hours until eight days at which time the experi-
ment was terminated. Data seem to indicate results will
depend to some degree on treatments compared at one time.

In Experiment V decomposed liquid manure (five
percent dry matter) was treated with Odor Mask (1430 PPM),
Pit-Zyme (360 PPM) or Sep-Zyme (360 PPM). Odor Mask was
found to increase offensiveness at this concentration.
Pit-Zyme decreased offensiveness at day eight. Sep-Zyme
"0" did not change offensiveness rating. Further study
needs to be made with these compounds.

Results of this study indicate certain treatments

evaluated were effective in changing odor produced from

Charles C. Stallings

fresh as well as decomposed dairy waste. Most of these
changes could be attributed to either antimicrobial or
oxidative properties of the additive that prevented forma-

tion of malodors or destroyed malodors already produced.

AN EVALUATION OF LIQUID DAIRY MANURE
TREATMENTS BY BIOLOGICAL, CHEMICAL

AND ORGANOLEPTIC TECHNIQUES

BY

Charles C. Stallings

A THESIS

Submitted to
Michigan State University
in partial fulfillment of the requirements
for the degree of

MASTER OF SCIENCE

Department of Dairy Science

1976

ACKNOWLEDGMENTS

I would like to acknowledge the following peOple
for their gracious assistance and advice:

My major professor, Dr. J. W. Thomas, for his
advice and encouragement.

The members of my graduate committee, Dr. Lee
Shull and Dr. John Gerrish, for help during my graduate
program.

Ms. Deborah Flint and Dr. Timothy Chang for doing
the total aerobic and anaerobic microbial counts.

Dr. John Gill for statistical advice.

Dr. Charles Lassiter for financial support as well
as making the facilities of the Dairy Science Department
available.

My odor panel members, Dave Bolenbaugh, Ray Bourne,
Pete Brodbeck, Jane Carstairs, Gary Dimenna, Mac Donaldson,
Arthur Felix, Neils Fogt, John Foldager, Dave Grusenmeyer,
Dave Harrison, Jim Kesner, Terry Kiser, Roger Kittok, Kay
Leining, Dr. Ivan Mao, Dr. Ken McGuffey, Tim Middleton,
John Peters, Jim Plog, Myron Rinck, Carol Roney, Joye
Schmidt, Mohamad Soejono, John Stellflug, Dwight Vines and

Becky Winters, for the use of their noses.

ii

Finally, my thanks to my wife, Martha Ann, for
assistance in preparing this manuscript and making it all

worthwhile.

iii

LIST

LIST

II.

TABLE OF CONTENTS

OF TABLES . . . . . . . . . . . . . . . . .
OF FIGURES . . . . . . . . . . . . . . . .
INTRODUCTION . . . . . . . . . . . . . . .
LITERATURE REVIEW . . . . . . . . . . . .

Characteristics of the Nose . . . . .
Properties of Odorants . . . . . . . .
Theories of Odor Perception . . . . .
Odor Evaluation . . . .
Compounds Involved in Odor Production

from Animal Wastes . . . . . . . . .

Ammonia and Amines . . . . . . . .
Organic Acids . . . . .
Hydrogen Sulfide, Disulfides,
Sulfides and Mercaptans . . . .
Carbonyls . . . . . . . . . . .
Indole and Skatole . . . . . . .
Alcohols . . . . . . . . . . . .
Esters . . . . . . . . . .
Carbon Dioxide and Methane . . .

Odor Production from Animal Wastes . .

Effect of Substrate on Odor
Production . . . . . . . . . . .
Effect of Moisture on Odor
Production . . . . . . . . . . .
Effect of pH on Odor Production .
Effect of Temperature on Odor
Production . . . . . . . . . . .

Aeration as a Means of Controlling Odors

Chemical Addition as a Means of
Controlling Odor . . . . . . . . . .

Lime 0 O O O O O O O O 0 O O O 0
Sodium Hydroxide . . . . . . . . .

iv

Page
vii

xi

\OQ-hw U H

13

17
21

22
24
25
27
28
29

30

31

37
39

42
43
45

45
47

III.

Chlorine . . . . . .

Paraformaldehyde and Formaldehyde

Potassium Permanganate . . . . .
Hydrogen Peroxide . . . . . . .
Masking Agents, Counteractants,
Deodorants and Digestive
Deodorants . . . . . . . . . .
Other . . . . . . . . . . . . .

Management as a Means of Controlling

MATERIALS AND METHODS . . . . . . . . .

Experiment I O I O O O O O O O O O 0

Determination of Total Aerobic and

Anaerobic Microorganisms . . .
Determination of pH . . . .
Determination of Total Solids .
Determination of Ammonia in Air
Odor Panel Evaluation . . . . .

Experiment II 0 O I O O O O O O C 0

Determination of pH and Total Solids

Determination of Total Ammonia in

the Manure . . . . . . . . . .
Nitrate Determination . . . . .
Odor Panel Evaluation . . . . .

Experiment III . . . . . . . . . . .

Determination of Total Aerobic
Microorganisms . . . . . . .

Determination of pH and Total Solids

Determination of Total Ammonia in

the Manure I O O O I O O O O O
Odor Panel Evaluation . . . . .

Experiment IV . . . . . . . . . . .

Determination of Total Solids .
Odor Panel Evaluation . . . . .

Experiment V . . . . . . . . . . . .

Determination of Total Solids .-
Odor Panel Evaluation . . . . .

Statistical Analysis . . . . . . . .

V

Page
47
52
54
57
59
61
63

63

69
69

69
69

70

70
70

71

71
71

72

Page

IV 0 RESULTS 0 O O O O O O O O C O O O O O O O O O O 73

Experiment I . . . . . . . . . . . . . . . . 73
Microbial Counts . . . . . . . . . . . . 73
pH . . . . . . . . . . . . . . . . . . . 75
Ammonia . . . . . . . . . . . . . . . . 78
Odor Panel Evaluation . . . . . . . . . 80
Experiment II . . . . . . . . . . . . . . . 84
pH 0 O O 0 O O O O O O O O O O O O O O O 8 6
Ammonia and Ammonium Ion . . . . . . . . 88
Nitrate . . . . . . . . . . . . . . . . 88
Odor Panel Evaluation . . . . . . . . . 88
Experiment III C O O O O O O i. O O O O O O O 91
Microbial Counts . . . . . . . . . . . . 91
pH 0 O O O O O O O O O O O O O O O O O O 93
Ammonia and Ammonium Ion . . . . . . . . 93
Odor Panel Evaluation . . . . . . . . . 96
Experiment IV . . . . . . . . . . . . . . . 96
Odor Panel Evaluation . . . . . . . . . 96

Experiment V . . . . . . . . . . . . . . . . 107

Odor Panel Evaluation . . . . . . . . . 109

V. DISCUSSION 0 O O O O O I O O O O O O O O O O O O 113
Influence on Microbial Numbers by

Additives O O O O O O O O O O O O O O O O 113

Influence on pH by Additives . . . . . . . . 117
Influence on Ammonia and Ammonium

Ion by Additives . . . . . . . . . . . . . 119
Influence on Odor Panel Evaluation

by Treatments . . . . . . . . . . . . . . 123

VI 0 SUWY O O O O O O O O O O O O O O O O O O O O 133

BIBLIOGRAPHY . . . . . . . . . . . . . . . . . . . . . 135

vi

Table

1.

9.

10.

11.

12.

13.

LIST OF TABLES

Compounds Identified in the Air from the
Anerobic Decomposition of Livestock
and Poultry Manure . . . . . . . . . .

Threshold Limit Values for Various Gases
Associated with Animal Waste Odors . .

Odor Thresholds in Air . . . . . . . . .

Characteristics and Perceptible Concen-
trations of Sulfur Compounds in Air .

Olfactory Thresholds and Maximum Allow-
able Concentrations for Some of the
AlCOhOlS o o o o o o o o o o' o o o o o

Olfactory Thresholds and Maximum Allow-
able Concentrations for Some of the
Esters O O O O O O O O O O O O O O O 0

Use of Restrictive Environments to Con-
trol the Formation of Manure Odors by
Anaerobic Decomposition . . . . . . .

Solid Waste Accumulation in Beef Cattle
FeedIOtS o o o o o o o o o '0 o o o o 0

Some Properties of Dairy Cattle Manure .
Manure Production of Domesticated Live-
stock per 1000 Liveweight Units
(lb. or kg.) 0 O O O O O O O O I O O 0

Moisture Content of the Manure and Feces
of Selected Domesticated Animals . . .

pH Values at Which Various Odorous Com-
pounds are 50 Percent Ionized at 25°C

Relationship of H28 in Water at 25°C as a
Function of pH . . . . . . . . . . . .

vii

Page

14

16
19

23

28

29

32

34

36

37

38

40

41

Table Page

14. Fraction of Total Ammonia Concentration
Present as NH3 as a Function of Tempera-
ture and pH 0 O O O O O O I O O O O O O O O O 4 2

15. Odor Evaluation . . . . . . . . . . . . . . . . 66

16. Aerobic and Anaerobic Microbial Numbers at
Four Intervals After Three Chemicals
were Added to Fresh Liquid Dairy
Manure (Experiment Ia) . . . . . . . . . . . . 74

17. Aerobic and Anaerobic Microbial Numbers at
Four Intervals After Three Chemicals
were Added to Fresh Liquid Dairy
Manure (Experiment Ib) . . . . . . . . . . . . 76

18. pH at Four Intervals After Addition of
Three Chemicals to Fresh Liquid Dairy
Manure (Experiment Ia) . . . . . . . . . . . . 77

19. pH at Three Intervals After Addition of
Three Chemicals to Fresh Liquid Dairy
Manure (Experiment Ib) . . . . . . . . . . . . 79

20. Ammonia in the Air Space over Fresh Liquid
Dairy Manure as Affected by Treatment
and Time (Experiment Ia) . . . . . . . . . . . 81

21. Ammonia in the Air Space over Fresh Liquid
Dairy Manure as Affected by Treatment
and Time (Experiment Ib) . . . . . . . . . . . 82

22. Offensiveness and Strength Ratings Four
and Five Days After Addition of Three
Chemicals to Fresh Liquid Dairy
Manure (Experiment Ia) . . . . . . . . . . . . 83

23. Offensiveness and Strength Ratings Four
and Five Days After Addition of Three
Chemicals to Fresh Liquid Dairy
Manure (Experiment Ib) . . . . . . . . . . . . 85

24. pH Before and After Addition of Four
Chemicals to Decomposed Liquid Dairy
Manure (Experiment II) . . . . . . . . . . . . 87

25. Total Ammonia in Manure After Addition

of Four Chemicals to Decomposed
Liquid Dairy Manure (Experiment II) . . . . . 89

viii

Table Page

26. Offensiveness Ratings at Three Intervals
After Addition of Four Chemicals to
Decomposed Liquid Dairy Manure
(Experiment II) . . . . . . . . . . . . . . . 90

27. Aerobic Microbial Numbers at One and
Eight Days After Addition of Four
Chemicals to Decomposed Liquid
Dairy Manure (Experiment III) . . . . . . . . 92

28.’ pH Before and After Addition of Four
Chemicals to Decomposed Liquid
Dairy Manure (Experiment III) . . . . . . . . 94

29. Total Ammonia in Manure Before and
After Addition of Four Chemicals
to Decomposed Liquid Dairy
Manure (Experiment III) . . . . . . . . . . . 95

30. Offensiveness Ratings at Three Intervals
After Addition of Four Chemicals to
Stored Liquid Dairy Manure
(Experiment III) . . . . . . . . . . . . . . . 97

31. Odor Panel Rankings at Three Time Periods
Comparing Two Concentrations of Para-
formaldehyde (PF) and Control
(Experiment IV) . . . . . . . . . . . . . . . 99

32. Odor Panel Rankings at Three Time Periods
Comparing Two Concentrations of H202
and Control (Experiment IV) . . . . . . . . . 100
33. Odor Panel Rankings at Three Time Periods
Comparing Two Concentrations of KMnO4
and Control (Experiment IV) . . . . . . . . . 101

34. Odor Panel Rankings at Three Time Periods
Comparing Paraformaldehyde (PF) to KMnO4
and Control (Experiment IV) . . . . . . . . . 102

35. Odor Panel Rankings at Three Time Periods
Comparing Paraformaldehyde (PF) and
H202 and Control (Experiment IV) . . . . . . . 104

36. Odor Panel Rankings at Three Time Periods

Comparing KMnO to H202 and Control
(Experiment IV? . . . . . . . . . . . . . . . 105

ix

Table Page

37. Odor Panel Rankings at Four Time Periods
Comparing Two Concentrations of H202
and Control (Experiment IV) . . . . . . . . . 106
38. Odor Panel Rankings at Four Time Periods
Comparing H20 to KMnO4 and Control
(Experiment 13) . . . . . . . . . . . . . . . 108

39. Odor Panel Rankings at Three Time Periods
Comparing Odor Mask to Pit-Zyme and
Control (Experiment V) . . . . . . . . . . . . 110

40. Odor Panel Rankings at Three Time Periods
Comparing Pit-Zyme to Sep-Zyme "O"
and Control (Experiment V) . . . . . . . . . . 111

41. Odor Panel Rankings at Three Time Periods
Comparing Odor Mask to Sep-Zyme "O" and
Control (Experiment V) . . . . . . . . . . . . 112

42. Characteristics of Manure Used in
Experiments I through V . . . . . . . . . . . 114

Figure

la.
lb.
1c.
1d.

2a.

2b.

LIST OF FIGURES

Hydrolysis of Urea . . . . . . .
Deamination of Amino Acids . . .
Transamination of Amino Acids . .

Decarboxylation of Amino Acids .

Formation of Volatile Organic Acids

the Degradation of Amino Acids

Formation of Volatile Organic Acids

the Degradation of Carbohydrates

Anaerobic Decomposition . . . .

Breakdown of Tryptophan to Skatole and

IndOIe O O O O O O O O O O O 0

Formation of Alcohols by Anaerobic
Decomposition . . . . . . . . .

Formation of an Ester by Condensation of

an Alcohol and an Organic Acid

xi

from

from

.Formation of Aldehydes and Ketones by

Page
18
18
18
18

21

21

26

27

27

29

I . INTRODUCTION

Liquid manure systems have become more common due
to the increase of intensive dairy production in many areas
of the country. One reason is that liquid manure can be
handled mechanically with a minimum input of labor. A
disadvantage of this system is the greater volume of waste
to be handled and disposed of, due to the necessity of
adding water to get manure into a liquid form. Another
drawback is increased odor problems associated with this
type of manure handling system.

Over 45 compounds have been identified in odorous
air over animal wastes. Most of these are reduced organic
compounds that are intermediate or end products of anaerobic
decomposition. Some of these gases are of a toxic nature
and are a concern to dairy farmers if present in sufficient
quantities. Both human and animal deaths have occurred in
isolated instances under enclosed conditions. Although
these toxic gases present problems at certain times, odors
probably receive the greatest amount of attention and com—
plaints.

Odors can be released during manure storage as well

as when applying to the land. The latter is usually the

biggest producer of odors. Most odor problems can be pre-
vented by proper manure management techniques, but with
the encroaching suburbs into agricultural areas, many
farmers find themselves with nonrural neighbors who object
to odors more than do usual rural residents. As a result
some situations necessitate the use of additives to con-
trol the release of odorous compounds into the atmosphere.
This study was undertaken to evaluate certain additives
presently in use as well as some that may have potential

use .

II . LITERATURE REVIEW

Characteristics of the Nose

 

The perception of an odor is a very complex process
in that many intricate physiological mechanisms are
involved. Because of this complexity the odor code has not
been entirely elucidated, but many of the essential details
are known.

For an odor to be detected it must enter the nasal
cavity by the exterior nares and travel to the olfactory
membranes that lie in the superior part of each nostril.
Amoore et a1. (1964) describe these organs as being two
patches of yellowish tissue, each about 2.4 sq. cm.
Embedded in these olfactory membranes are two types of
nerve fiber which are involved in detection.

The major type of fiber is composed of bipolar
nerve cells derived originally from the central nervous
system, and there may be as many as 100 million of these
cells in the olfactory epithelium (Guyton, 1971). These
receptor cells have hairs or cilia that project into the
mucus that coats the inner surface of the nasal cavity, and
it is theorized that these hairs react to odorous molecules.

These hairs in turn act to stimulate the olfactory cells,

which cause an impulse to travel to the brain where it is
integrated and interpreted in terms of the quality and
quantity of the odor.

The lesser type of nerve fiber found in the
olfactory membrane is the trigeminal nerve, which is sensi—
tive to certain kinds of molecules. Montcrieff (1946)
describes this type of sensitivity by a dog that has had
the olfactory nerve severed but is still sensitive to
ammonia and other irritants. This chemical sensitivity
seems to be distinct from smell, and the receptors are the
free nerve endings of the trigeminal nerve.

The olfactory cleft is yellow in color compared
with the reddish tint of the interior surface of the nasal
cavities. Moncrieff (1946) states that the pigment appears
to be connected to the mechanism of the olfactory apparatus.
Moulton (1970) reports that in most mammals the olfactory
epithelium contains retinol, beta-carotene and at least
four noncarotenoid pigments considered to be chromopro-
teins. The yellowish-brown color is probably from the
noncarotenoid pigments. Theories implicating pigments in
the primary olfactory transduction process have many
difficulties, but the dense concentration of olfactory

pigments in some species imply some functional role.

Properties of Odorants

 

All odorous substances logically have certain

common basic properties since specific physiological

reactions must occur for an odor to be perceived. Backman
(1917) concluded that both aqueous and lipoid solubility
are necessary for an odorous molecule to be detected.
Montcrieff (1946) postulates that odorous molecules must
be volatile and thus have a vapor pressure. This volatility
allows the molecules of the odorant to come into contact
with the olfactory hairs which will initiate an olfactory
response. Therefore a substance with a low vapor pressure
will have fewer molecules in the air compared with a sub-
stance with a high vapor pressure.

Miner (1974) compiled a list of certain basic
properties that have been observed in relation to odors:

1. Only volatile substances are odorous.

2. Air movement into the nasal cavity is necessary
to feed the receptors.

3. When air movement stops, odor sensation vanishes.

4. Water, though having the characteristics of other
odorants, has no odor (as detected by humans).

5. Gases such as oxygen and nitrogen have no odor.

6. Exposure to an odor produces a high initial
response and a declining response with continued
contact (adaptation).

7. A strong odorant completely exhausts the capacity
to perceive the odor after 2 or 3 minutes of
exposure (fatigue).

8. A change in odor sometimes occurs on dilution of
the odorant.

9. Some animals have a better developed sense of
smell than humans.

10. Isomers (having the same chemical composition)
have widely differing smells.

11. Some compounds with widely differing chemical
characteristics have similar smells.

12. Some odorants are perceived at a concentration of
one millionth that of others.

The necessity of odorous molecules being both water
and lipid soluble is explained by Amoore et al. (1964).
Water solubility enables the molecules to reach the nerve
endings which are covered by a watery film (mucus), and
lipid solubility allows them to penetrate the nerve endings
through the lipid layer that forms part of the surface
membrane.

A scientifically valid odor theory must meet
several criteria. Schultz (1964) explained that a valid
odor theory must explain odor thresholds, suprathreshold
intensity, adaptation to odors, differences in quality of
odors, differences in odor relationship to chemical char-
acteristics and still must follow the biochemical and
physiological information known about the olfactory sense
organ. This rigorous set of demands has hindered deve10p-
ment of a completely valid odor theory.

In an attempt to unify differing aspects of
olfaction Montcrieff (1966) described the mechanism as
occurring in six stages:

1. The molecules of a volatile substance are lost to
the atmosphere.

2. Some of the molecules, inspired with air into the
nasal cavity, are directed to the olfactory
receptors.

3. The odorous molecules are adsorbed on apprOpriate
sites on the olfactory nerve cells.

4. The adsorption is accompanied by an energy change.
5. An electrical impulse, generated by the energy
change, travels from the olfactory receptor to
the brain.
6. The brain processes the information and transmits
the sensation of smell.
Theories of Odor Perception

The first theories dealing with odor perception
were formulated in the late 18003 and early 19003.
Montcrieff (1946) explained that most early theories were
concerned with vibrations, and many theorized that actual
contact of the odorous molecules with the olfactory region
was unnecessary.

Most of the theories to date differ in the mech—
anism by which the odorant transmits the message to the
olfactory nerve. Mechanisms that appear most feasible are
molecular vibration, chemical reaction and physical
adsorption.

Dyson (1938) introduced the vibrational theory
which postulates that odorous substances possess intra-
molecular vibrations. Theoretically, these vibration fre-
quencies fit specific receptor sites in the nose producing
the initial stimulus for odor perception. Wright (1964)
explains that the volatility, solubility, adsorbility,

etc. may affect the odor quantity (strength), but the

quality of the odor will depend on the intra-molecular
vibrations.

The chemical theory was prOposed and evaluated by
several researchers, but now has been largely discounted.
The theory assumes the odorant molecules are changed via
a chemical reaction after being adsorbed on the receptor
sites, and this elicits an olfactory response.

Amoore (1963) proposed the stereochemical theory
of odor perception. This theory involves a fit between
the odor molecule and a receptor site. These sites are
considered to be ultramicroscopic slots in the nerve-fiber
membrane that have a distinctive shape and size. Amoore
et a1. (1967) have revised this original theory to allow
for a two-dimensional instead of a three-dimensional fit.
This is consistent with the theory that the cross-sectional
area is the important steric characteristic of the odorant.
Odor perception is stimulated by the energy change mediated
by the adsorption of the odorant molecule on the olfactory
nerve receptor site.

The penetration theory (Davies and Taylor, 1954)
prOposes that a puncture occurs in the lipoid membrane of
the olfactory nerve when an odorous molecule is adsorbed.
This leads to an unbalance of Na+ and K+ ions which is con-
sidered to be the stimulus for the olfactory perception

process.

Barth (1970) summarized the major theories of
olfaction and noted that all of them have two points in
common:

1. Adsorption of the odorant molecule on the olfactory
nerve is necessary for initiation of the process,
and

2. The cross-sectional properties of the molecule

are a controlling factor.

Odor Evaluation

 

An accurate qualitative and/or quantitative evalu-
ation of an odor is difficult if not impossible. As a
result many methods of evaluation have been developed most
of which use a human odor panel.

Foster (1964) explains that even the most highly
trained nose is variable. Therefore objective measure-
ments necessitate the utilization of more than one nose.

In other words any one person can produce an atypical
response, but this can be moderated by using several noses.
The likelihood that an atypical response will cause a
misinterpretation is reduced in direct proportion to the
number of persons on the odor panel.

A major problem with an odor panel is the
possibility of olfactory fatigue. Earth (1970) observes
that the initial response to an odor is strong, with a
decreasing response with continued contact. Finally, after

prolonged contact, the ability to perceive the odor is

10

exhausted. With a strong odorant this can occur in two to
three minutes.

Montcrieff (1946) pointed out that odor fatigue
is selective so that fatigue from one odor will not
decrease the ability to perceive other odors. Baker (1964)
observed that when background odors of similar type were
present there was an inhibition of ability to evaluate the
odor under study. However, when dissimilar background
odors were present, enhancement of the ability to evaluate
the odor under study was noted. He concluded that under
no conditions should background odors be present in odor
evaluation processes when exactness was desired.

Baker (1964) also tested the ability of odor
panels to perceive odors at different environmental tempera—
tures. Evaluation of odor was compared at environmental
temperatures of 21°, 40° and 60°C. At 21° (room tempera-
ture) the panelists considered the odor to be dead compared
to the 40° comparisons which they preferred. The 60°
evaluations produced fleeting initial responses that were
lost on second inhalation.

Mitchell et a1. (1964) reported that the perception
of odor is age and sex dependent. They observed that there
is a progressive increase in olfactory perception thresholds
from 8 to 25 years of age. After 25 the threshold remains
relatively constant until around the age of 50 then

declines. Women were observed to have a more sensitive

11

sense of smell than men, but it was not known if this was
because of their sex or because fewer of them smoked.

Odor can be evaluated in terms of either strength
(quantity) or quality. The most common method used to
measure strength is by dilution to extinction (Miner,
1974). The odorant is diluted with an odor-free medium
(usually air or water) until the odorant is just barely
detectable. This is called the threshold value.

Odor strength is presented as either the threshold
odor number (TON) or the odor intensity index (011). The
greatest dilution of the odorant with odor-free medium until
the threshold is reached has been termed TON. The number
of times an odorant must be diluted by half with an odor-
free medium until the threshold is reached is called the
011. The odor intensity index is the more popular of the
two methods.

Miner and Smith (1975) describe an instrument for
field use which can relatively easily measure odor intensity.
This instrument, called a scentometer, is a device that can
mix air passed through activated carbon absorption beds
(odor free air) with air from the environment (odorous
air). This air mixture is then taken into the nostrils
by the nasal outlets, and depending upon the size of the
inlet port when the odor is first detected a dilution value

can be determined.

12

Odor quality is more difficult to measure than odor
strength. Burnett and Dondero (1968) attempted to measure
odor quality by comparing treated liquid poultry manure to
an untreated standard using an odor panel. They used a
scale of similarity with 8 being "extreme similarity" down
to 0 as "no similarity." Therefore a quantifiable number
relates the treated manure to the standard untreated manure.

Ludington et al. (1969) used an odor panel to rate
jars of manure from 0 as "not offensive" up to 10 as ”very
offensive." Jars were painted black so as not to bias the
odor panel by seeing the manure. Cole et a1. (1976)
attempted to evaluate strength of odor as well as quality.
Using an odor panel, quality was measured as above but
strength was evaluated using a scale with 0 being "no odor"
and 10 being "very strong." They concluded that the
panelists could not distinguish between strength and
offensiveness. In other words, a strong odor was usually
an offensive odor.

In addition to the organoleptic methods of
evaluating odors, several instruments have been used. The
gas-liquid chromatograph (GLC) can separate and quantify
the odorant compounds involved, but no measure of quality
is obtained. The GLC has been found less sensitive than
the nose in detecting odor (Kendall and Neilson, 1964).
They concluded that panelists could detect odors in con-

centrations 10 to 100 times more dilute than the GLC.

13

Miner (1974) mentioned mass spectroscopy, thin-
layer chromatography and even mechanical noses as being
used in evaluation of odor, but none could equal the human
nose in determining the quality and intensity of complex
odorants.

Another approach is to capture an individual com-
ponent of the odor by absorbing it in a solvent. Concen-
trations can then be measured by colorimetric or other
techniques. Miner (1974) reviews methods for the capture
and measurement of ammonia, hydrogen sulfide and mercaptans.
The one or two components thus measured, do not necessarily
give a good indication of the level of odor as importance
of other components are ignored. Only a limited number of
the gases have been routinely measured as parameters of
odor intensity.

Compounds Involved in Odor Production
from Animal Wastes

 

 

Miner (1974) has reported that about 45 compounds
have been found in odorous air near animal wastes. He
considers the amines, mercaptans, organic acids and
heterocylic nitrogen compounds as being of greatest odor
significance in air exposed to the products of anaerobic
decomposition of livestock and poultry manures. His list
of odorous compounds appears as Table 1. Most of the

listed compounds are reduced intermediate or end products

14

TABLE 1

Compounds Identified in the Air from the Anerobic

Decomposition of Livestock and Poultry Manure

 

Alcohols

Methanol
Ethanol
2-Propanol
n-Propanol
n-Butanol
iso-Butanol
iso-Pentanol

Acids

Butyric
Acetic
Propionic
iso-Butyric
iso-Valeric

Amines

Methylamine

Carbonyls
Acetaldehyde

Propionaldehyde
iso-Butyraldehyde
Hexanal

Acetone
3-Pentanone
Formaldehyde
Heptaldehyde
Valeraldehyde
Octaldehyde
Decaldehyde

Sulfides
Dimethyl sulfide
Diethyl sulfide

Nitrogen heterocycles
Indole
Skatole

Disulfides

 

Esters

Ethyl formate

Methyl acetate
iso—Propyl acetate
iso-Butyl acetate
iso-Propyl propionate
Propyl acetate
n-Butyl acetate

Fixed Gases

Carbon dioxide
Methane

Ammonia
Hydrogen sulfide

Mercaptans

Methylmercaptan

 

Source: J. R. Miner (1974).

15

of anaerobic decomposition sufficiently volatile to escape
from the liquid phase.

Different gases have varying concentrations at
which they can be perceived. Threshold limit values for
various gases are shown in Table 2.

To evaluate the "total" quality of an odor it is
almost impossible to add together the "subtotal" qualities
of the individual gases. Baker (1964) reported that a
mixture of two or more gases could be completely different
from each individually. For example, sub-threshold con-
centrations of certain compounds when mixed together may
or may not yield an odor. This interaction between gases
can be either additive (the resulting odor is the sum of
the individual components), synergistic (the resulting odor
is greater than predicted by direct addition) or antagon-
istic (the resulting odor is less than expected by direct
addition). He concluded that all three interactions will
occur and synergism and antagonism were the rule and not
the exception.

Most of Baker's results are based on mixtures of
two compounds. Guadnagi et al. (1963) tested mixtures of
up to ten odorants, and found the reactions are mostly
additive rather than synergistic or antagonistic. Miner
(1974) states that this would be anticipated in complex
systems where the more common additive reaction outweighs

the other unusual reactions. Apparently, extensive

16

TABLE 2

Threshold Limit Values* for Various Gases
Associated with Animal Waste Odors

 

9

Substance Concentration 10' g/l

 

Acetaldehyde 360
Acetic Acid 25
Ammonia 35
n-Butyl acetate 710
Butyl mercaptan 35
Diethylamine 75
Dimethylamine l8
Ethylamine l8
Ethyl mercaptan 25
ISOpropylamine 12
Methylamine 12
Methyl mercaptan 20
Triethylamine 100

 

*Threshold limit values refer to airborne concen-
trations under which nearly all workers may be repeatedly
exposed without adverse effect.

Source: American Conference of Governmental
Industrial Hygienists (1967).

17

’interaction occurs to produce the odor perceived from the
decomposition of animal waste. Thus, the odor which is
smelled originates from many complex and different processes
during the production of odorous gases plus their inter-

action after escape from the liquid phase.

Ammonia and Amines

 

Merkel et a1. (1969) detected ammonia and amines
in the atmosphere of a swine building. White and Taiganides
(1969) reported ammonia and amines in odors from dairy
wastes using a GLC. Ulich and Ford (1975) used selective
absorbents to show amines and possibly ammonia as important
components of cattle feedlot odors.

Ammonia and amine formation result from decomposi-
tion of both animal and plant protein (Miner and Hazen,
1969). Urea, a constituent of urine, can be hydrolyzed to
ammonia via urease (Sawyer, 1970). Also uric acid can be
degraded to ammonia. The formation of ammonia and amines
is shown in Figure la through 1d. The enzymes involved in
these transformations are produced by microbes.

Ammonia is described as being pungent, sharp and
somewhat irritating (Miner and Hazen, 1969). The amines
have a similar odor, but very much more severe and longer
lasting. Table 3 presents the odor thresholds of ammonia
and some amines.

Amines are detectable at much lower concentrations

than ammonia, and trimethylamine is the strongest amine

18

 

O
H
HzN-C-NH2 urease >> NH3 + CO2
urea ammonia carbon dioxide

Fig. la.--Hydrolysis of Urea.

 

R R
I , I
H-C'-NH2 deam1nase :> NH3 + T.__O
COOH COOH
amino acid ammonia a-keto acid

Fig. lb.--Deamination of Amino Acids.

 

 

R R R R
I I _ I l

H-C-NH + C20 transaminase \ CZO + H-C-NH
I 2 I 7 I I 2
COOH H COOH H

amino acid ketone a-keto acid amine
Fig. lc.--Transamination of Amino Acids
NHZ NHZ
R-CHZ-CH-COOH decarboxylase \R-CH-CH3 + (:02

‘ /'

amino acid amine carbon dioxide

Fig. 1d.--Decarboxylation of Amino Acids.
Source of Fig. la and 1b: J. R. Bronk (1973).

Source of Fig. 1c and 1d: J. R. Miner and T. E.
Hazen (1969).

19

TABLE 3

Odor Thresholds in Air

 

 

Compound PPM (volume)
Ammonia 46.8
Methylamine 0.021
Dimethylamine 0.047
Trimethylamine 0.00021

 

Source: A. G. Stern (1968).

listed. Stephens (1971) considers all amines to have odors
suggestive of feedlot areas.

Taiganides and White (1968) pointed out two signifi-
cant properties of ammonia were being lighter than air and
soluble in water. Thus ammonia moves in air throughout a
building from the point of generation, and represents a
significant loss of nitrogen from manure. Solubility in
water allows liquid systems to keep much of the ammonia
in the dissolved form.

Instances have been cited where ammonia levels
caused discomfort to animals (Taiganides and White, 1968).
In poultry houses, 20 PPM caused no sign of distress, but
at 200 PPM, signs of discomfort were seen during the first
few days, followed by loss of appetite and loss of weight.
Birds exposed to 1000 PPM developed photophobia (fear of
light) with very little mortality. Ammonia levels of 2000
PPM over a three to four week period caused keratocon-

junctivitis (erosion of the cornea).

ShI

SI'II

ho

GIT

ho

an
OC

3C

PI

20

A 30 kilogram gilt placed in an ammonia environment
of about 280 PPM for 36 hours initially frothed at the mouth
then had excessive secretions around the nose and mouth
(Stombaugh et a1., 1969). These excessive secretions per-
sisted but frothing disappeared after a short time. A
short, irregular respiratory pattern developed along with
sneezing and head shaking. Convulsions occurred after 36
hours in this environment. After being taken from the
environment the pig continued to have convulsions for three
hours then appeared normal within a few hours.

Taiganides and White (1968) list ammonia as being
an irritant of the throat and eyes. Coughing and frothing
occur at high levels, and they consider 10 to 50 PPM
acceptable for animals in confinement operations. With
proper ventilation this can be achieved.

Miner and Hazen (1969) passed air from a swine
building through a boric acid solution to capture ammonia
and through acetic acid to collect the amines. They found
ammonia concentrations to be below the threshold value
previously given. They concluded either ammonia is not an
important part of the odor or due to interaction with other
odorous compounds a synergistic or additive reaction occurs
allowing ammonia to be detected at concentrations below
its threshold. The amines were not quantified, but

methylamine, ethylamine and triethylamine were identified.

21

Organic Acids

 

Deibel (1967) found butyric acid to be a component
of decomposing poultry manure while fresh manure had none.
Acetic, propionic, iso-butyric and iso-valeric acids were
identified as components of chicken manure (Burnett, 1969).
Bell (1971) found a correlation between the volatile fatty
acid content and odor level in liquid poultry manure.

Volatile organic acids can be produced by the
breakdown of protein and carbohydrates by microorganisms.
Pathways for organic acid production from protein and

carbohydrate are shown in Figure 2a and 2b.

 

 

H H H
| l
R-C-COOH \\ R-C-COOH ‘\\ R-C-COOH
I / l / l
NH2 OH H
amino acid hydroxy acid volatile organic acid

Fig. 2a.--Formation of Volatile Organic Acids from the
Degradation of Amino Acids

()I H
I

(95111206)n 9 c6leo6 BHBC-C-COOH ; R-T-COOH
H

polysaccharide monosaccharide pyruvate volatile organic
. acid

Fig. 2b.--Formation of Volatile Organic Acids from the
Degradation of Carbohydrates.

Source of Fig. 2a and 2b: J. R. Bronk (1973).

22

Acetic acid is odorous at 1 PPM, and butyric acid
at 0.001 PPM (Stephens, 1971). Miner (1974) states that
butyric and valeric acids have very disagreeable odors while
Gerrish (1974) describes acetic acid odor as similar to
vinegar and propionic acid as similar to swiss cheese.

Miner (1974) describes a technique for the col-
lection and measurement of volatile organic acids from the
air. This is done by absorbing the VFA's in an alkaline

solution, acidifying and distilling.

 

H drogen Sulfide, Disulfides,
Squides andiMercaptans

 

Burnett and Dondero (1969) noted an increase in
soluble sulfides with an increase in odor intensity in
liquid poultry manure. Day et a1. (1965) detected hydrogen
sulfide in a swine unit. White et a1. (1971) tentatively
identified hydrogen sulfide, diethyl sulfide and dimethyl
sulfide in air from liquid dairy waste using A GLC. A GLC
and ionization mass spectrometer was used to confirm the
presence of diethyl sulfide and dimethyl sulfide in dairy
waste volatiles (Ifeadi et al., 1975). Ulich and Ford
(1975) used selective absorption liquids to capture hydro-
gen sulfide, disulfides and mercaptans, and found all
present in air above cattle manure. Fosnaugh and Stephens
(1969) detected the mercaptans as being a component of

feedlot odor.

23

White et a1. (1971) state that decarboxylation of
sulfur amino acids occurs with a release of amines and
sulfur compounds. These sulfur compounds occur in several
forms depending on the degree of breakdown. Under anaerobic
conditions the sulfate ion is reduced to the sulfide ion
which establishes an equilibrium with the hydrogen ion to
form hydrogen sulfide. This is pH dependent.

Mercaptans (R-SH) have a structure similar to the
alcohols (R-OH) except oxygen is replaced by sulfur.
Mercaptans along with the other sulfur compounds are
detectable at low levels in the atmosphere. Table 4 lists

some of the common sulfur compounds, and concentrations

TABLE 4

Characteristics and Perceptible Concentrations
of Sulfur Compounds in Air

 

Concentration
Substance Odor Characteristic causing faint
odor 10'9 g/l

 

n-Butyl mercaptan Strong, unpleasant 1.4

Carbon disulfide Aromatic odor, 2.6
slightly pungent

Ethyl mercaptan Odor of decayed cabbage 0.19

Hydrogen sulfide Odor of rotten eggs, 1.1
nauseating

Methyl mercaptan Odor of decayed 1.1

cabbage or onions
Propyl mercaptan Unpleasant odor 0.075

 

Source: J. P. Sheehy et a1. (undated).

24

causing a faint odor in air. All of the compounds listed
have not been identified in the air from degradation of
animal wastes.

Of the sulfur compounds hydrogen sulfide occurs
most frequently in the atmosphere from animal waste decom-
position. Taiganides and White (1968) report that hydrogen
sulfide is heavier than air and thus will stay near the
floor in nonventilated and quiescent rooms. Also it is
soluble in water.'

Animals exposed continuously to about 20 PPM
hydrogen sulfide have been described as being nervous,
having photophobia and anorexia (loss of appetite)
(Taiganides and White, 1968). At 50 to 200 PPM hydrogen
sulfide, vomiting, nausea and diarrhea may develop, and
at approximately 1000 PPM unconsciouSness and death can
occur. Actual cases of hydrogen sulfide toxicosis in both
humans and animals have occurred in connection with storage

of manure.

Carbonyls

 

Carbonyls have been identified in a swine building
atmosphere using a GLC (Merkel et al., 1969; Hartung et al.,
1971). Bethea and Narayan (1972) found aldehydes as com-
ponents of odor evolving from beef cattle manure. Ifeadi
et a1. (1975) identified carbonyls in dairy cattle waste.

Carbonyls get their name from the chemical carbonyl

group which is present in all aldehydes (R-2=O) and

25

H
ketones (R-C-R). A scheme for their formation is in

Figure 3 as suggested by Miner (1974).

Hartung et a1. (1971) say that carbonyls are
probably not the most noticeable offenders in air from
animal waste, but they can be penetrating_and irritating
to the eyes and mucous membranes. The lower aldehydes,
such as formaldehyde, are suffocating at higher levels.

Hartung et a1. (1971) found only one carbonyl
in the odor from liquid swine manure at a concentration
above the threshold value. They hypothesized that the
carbonyls that were present at concentrations below thresh-
old values would contribute to the overall odor through

additive interactions.

Indole and Skatole

 

Using a GLC Burnett (1969) identified indole and
skatole in the air over chicken manure. He found about
18 times more skatole than indole and concluded both were
a significant component of poultry waste odor. Bethea and
Narayan (1972) found both indole and skatole in the atmos—
phere from a steer confinement chamber.

Indole and skatole are both products of tryptophan

breakdown as indicated in Figure 4:

26

.cowuwmomeoooo ownouomsd an monoumm can mopwamoafl mo coHumEHOMII.m .mHm

moowsmvam
onOIm

_>

m

 

 

 

 

mGOADHUcoo
ownouowcm
ocoumx mum>su>m moflnmnoommosoe moaumnoommhaom
x \. c
mIoIm / 983350 mooououommA mofimmo / 103%”:
canoummcm

__ __
o o

27

/ C-CH ji-C00H / -CH / CH
\ ‘ CH 2 EH2 _ "> \ 'EH 3 _—m \ l 63
N N.

tryptophan skatole indole

Fig. 4.—-Breakdown of Tryptophan to Skatole and Indole.

Burnett (1969) considers indole and skatole to be
important because of their strong, harsh odors that
tenaciously tend to cling to clothing for long periods.
Summer (1971) lists skatole as having an olfactory thresh-

old at 7.5 x 10"8 ppm.

Alcohols

Deibel (1967) found ethanol to be one of the
chief components of decomposing poultry manure odor.
Bethea and Narayan (1972) identified methanol, ethanol and
2-propanol in the atmosphere of a beef cattle confinement
chamber. Merkel et al. (1969) identified alcohols as being
present in a swine building atmosphere.

Alcohols are characterized by the hydroxy group
(R-OH), and are the result of the anaerobic fermentation

of carbohydrates as noted in Figure 5.

O
(C6H1206)n___9 C6H1206 _> H3c-c—coon --_..._>R-OH
polysaccharide monosaccharide pyruvate alcohol

Fig. 5.--Formation of Alcohols by Anaerobic Decomposition.

28

Alcohols have olfactory thresholds that are high
compared to many other components of anaerobic decomposi-
tion. Some of the more common ones are shown in Table 5.
These values would lead us to believe that alcohols as a
class are relatively unimportant as to odor intensity;

however, their additive or synergistic effects are unknown.

TABLE 5

Olfactory Thresholds and Maximum Allowable
Concentrations for Some of the Alcohols

 

Threshold Max. Allowable

 

Pollutant Concentrations
(PPM) (PPM)
iso-Butanol 40 120
n-Butanol 11 100
Ethanol 50 1000
Methanol 5900 200

 

Source: W. Summer (1971).

Esters

Bethea and Narayan (1972) found the esters ethyl
formate, methyl acetate, iso-propyl acetate, iso-propyl
propionate and iso-butyl acetate as being components of
odors from dairy cattle waste.

The formation of the esters involves the con-
densation of an alcohol and an organic acid. This

reaction is shown in Figure 6.

29

R-OH + R-COOH ——.—-——.-> R-COOR' ‘
alcohol organic acid ester
Fig. 6.--Formation of an Ester by Condensation of an
Alcohol and an Organic Acid.
The esters like the alcohols have relatively high
threshold values. Table 6 shows the odor threshold values

and maximum allowable concentrations for some esters.

TABLE 6

Olfactory Thresholds and Maximum Allowable
Concentrations for Some of the Esters

 

 

' Max. Allowable

Pollutant Th?§:;?ld Concentrations
(PPM)
iso-Butyl acetate 4 - .. 200
n-Butyl acetate 7 150
Methyl acetate 200 200
iso-Propyl acetate 30 200
n-Propyl acetate 20 200

 

Source: W. Summer (1971).

Carbon Dioxide and Methane

 

Carbon dioxide and methane have been identified
in the atmosphere of a swine building (Day at al., 1965;
Skarp, 1975). Taiganides and White (1968) describe carbon
dioxide and methane as being colorless, odorless gases.
Carbon dioxide is heavier than air and highly soluble in
water, while methane is much lighter than air and only

slightly soluble in water.

30

Carbon dioxide is produced both in aerobic and
anaerobic animal waste systems by microorganisms and
usually in large amounts. Methane on the other hand will
be produced only under anaerobic conditions under narrow
ranges of temperature and pH. A pH below 6.5 inhibits
methane producing bacteria (Miner, 1971).

Both gases are considered relatively unimportant
in the total odor System since neither has an odor.
Taiganides and White (1968) describe them both as asphyxi-
ants having physiological effects only at high concen-
trations.

Taiganides and White (1968) point out that there
is no scientific evidence that odors will affect the health
of animals and humans even though these gases cause irri-
tation. This was indicated by Winslow and Greenberg (1918)
who kept young guinea-pigs under normal conditions and
others of similar age in an atmosphere of foul smelling
air that had been passed over human and dog feces. They
found that during the first week the controls grew at a
faster rate, but during the second week the two groups
grew about equally. Therefore a foul odor per se apparently

has no permanent ill-effect on growth.

Odor Production from Animal Wastes

 

Odor produced from decomposing animal waste varies

with species of animal, ration consumed, amount of moisture

31

in the waste, temperature, pH and many other parameters
plus some unknown factors.

Manure serves as a substrate for many micro-
organisms present in the environment. The subsequent
breakdown of the complex manure components by these micro-
organisms produce odor. Microorganisms utilize the energy
in manure and produce degradation products "further down"
the metabolic chain.

Miner (1974) lists several ways of preventing
formation of odorous breakdown products by maintaining an
environment unsuitable for anaerobic microorganisms.

They are: (a) provide an aerobic environment, (b) maintain
the moisture content so low that growth is inhibited,

(c) control the pH so that growth is inhibited, (d) adjust
the temperatures outside the region of bacterial growth,
(e) add a chemical which inhibits biological growth or

(f) change the microbial population so the formation of
specific odorous compounds is avoided.

Miner (1974) shows applications and limitations of
each technique in Table 7.

Effect of SubStrate on
OdOr Production

 

 

The type of manure produced will vary from animal
to animal. The obvious example is the difference between
ruminants and nonruminants. Miner (1971) explains the

difference as being a basic difference in type of ration

32

TABLE 7

Use of Restrictive Environments to Control
the Formation of Manure Odors by
Anaerobic Decomposition

 

 

Technique Application Limitation
Aerobic Oxidation ditch Power and equipment
environment Aerated lagoon costs
Moisture Manure dryers Manure transport
control Power ventilated Control of water
poultry manure leaks
pits
pH adjustment Lime application Ammonia release,
cost, solids
increase
Temperature Freezing Cost-handling
Chemical Chlorination Cost
inhibition
Microbial Digestive aids Technology
population
adjustment

 

Source: J. R. Miner (1974).

33

consumed. Ruminant diets contain cellulose fibers while
nonruminants contain little if any cellulose. Conse-
quently ruminant feces usually contain greater amounts of
cellulose fiber than nonruminants.

Composition of animal manure is dependent on
digestibility, protein and fiber content of the ration,
and the nature of feed additives in that ration (Loehr,
1968). These factors can directly affect the type of
microorganisms that predominate in the manure. Rations
high in cereals will produce feces with appreciable levels
of starch. Miner (1971) states that fecal carbohydrates
will stimulate both bacterial and fungal growth. The
carbohydrates are broken down to organic acids, aldehydes,
ketones and alcohols which can also stimulate growth of
some types of microbiota. These products are all com-
ponents of odor.

Ration composition has a major effect on the
amount of waste produced as noted in Table 8 (Wells et al.,
1972). The feedzwaste ratio is much greater for the all
concentrate ration, i.e., more of the concentrate feed is
utilized and not excreted compared to the 12 percent
roughage diet.

Loehr (1968) states that ruminants tend to produce
relatively large amounts of fecal wastes compared to amounts
of feed consumed. Simple stomached animals consume diets

more highly digestible, therefore they usually produce less

34

TABLE 8

Solid Waste Accumulation in
Beef Cattle Feedlots

 

 

All-concentrate 12% roughage

Number of animals 23 24
Feed dry matter, 1b. 60,768 77,110
Waste accumulation

Total pounds 19,110 44,930

Dry matter, lb. 8,982 21,072
Feed: waste ratio, . .

D.M. basis 6.8.1 3.7.1
Daily D.M. waste
accumulation

Per head 2.3 5.0

Per 100 lb. live

wt., 1b. 0.31 0.65

 

Source: D. M. Wells et a1. (1972).

waste compared to the amount of feed consumed. Fisher
(1974) claims that the body size of a lactating dairy cow
is more important than extent of digestibility or the pro-
portion of concentrate in the ration in determining the
total volume of excreta.

Grub et a1. (1969) point out the fact that plant
components lignin, cellulose and hemicellulose are rela-
tively stable materials that can be broken down only very
slowly by microorganisms. Because these components repre-
sent a large fraction of high roughage feeds, ruminant

feces may not be as readily available substrate for

35

microbial decomposition as nonruminant feces and thus, the
amount of odor produced may be less.

As feces composition varies from species to species
so will urine. Blosser (1964) observed that the urinary
wastes from herbivores tend to be more alkaline than urine
from carnivores or omnivores. Diets of herbivores contain
higher concentrations of potassium, calcium and magnesium
than diets of carnivores or omnivores and presence of these
elements increase pH of the urine. This may have a direct
affect on odor production since pH determines the degree
of volatility of odorous gases.

The production of odor from decomposing manure may
also be affected by compounds excreted in the waste such
as antibiotics, feed additives, plant phenolic residues,
etc. Morrison et a1. (1969) suggested that antibiotics
excreted in the waste of beef cattle might have a direct
effect on decomposition characteristics. They concluded
that this effect could be by the antibiotic decreasing
the rate of breakdown by inhibiting the degradative micro-
organisms or antibiotic resistant microorganisms pro-
liferating and producing metabolites contributing to the
enhancement or abatement of feedlot odor.

As stated before, the waste characteristics will
vary depending on the type of ration consumed, but there
are certain basic characteristics that can be assumed for

each species. Dale and Day (1967) gave some of the average

36

physical properties of dairy cattle manure shown in
Table 9. This data was collected from seven high producing

dairy cows with an average weight of 1500 pounds.

TABLE 9

Some Properties of Dairy Cattle Manure

 

Average daily manure production 107.8 lbs.

Portion of manure as feces 68.8 percent
Portion of manure as urine 31.2 percent
Percent body weight 7.22 percent
Moisture content of feces 82.7 percent
Moisture content of urine 95.1 percent
Average moisture content of manure 87.5 percent

 

Source: A. C. Dale and D. L. Day (1967).

Miner and Smith (1975) compiled Table 10 comparing
the manure production of different species per 1000 live-
weight units.

On an equal weight basis the dairy cow produces
more feces and urine than any of the other domestic animals.
This is mainly due to the type and amount of feed since
dairy cows are fed for high levels of production. Poultry
excrete nitrogen as uric acid along with the feces, hence
no liquid urine is produced.

Dale (1971) observed that most of the odor control
research to that date had been done with either swine or
poultry wastes since odors from swine and poultry production
units were more objectionable. Since that time, concen-

trated confinement production units have become more

37

TABLE 10

Manure Production of Domesticated Livestock
per 1000 Liveweight Units (lb. or kg.)

 

Raw Manure . .
Feces: ur1ne rat1o

 

(wt./day)
Dairy cow 82 2.2
Beef feeder 60 2,4
Swine feeder 65 1,2
Sheep feeder 40 _ 1,0
Poultry layer 53 _--
Poultry broiler 71 ---
Horse 45 4.0

 

Source: American Society of Agricultural Engineers
(1973).

common in the dairy industry with a resulting increase in

odor problems.

Effect of Moisture on
Odor Production

 

 

Ludington et a1. (1969) reported that there was an
apparent relationship between moisture content and level
of offenSiveness of manure. Sobel (1971) used chicken
manure to show that as the percent moisture decreased from
90 to 10 a corresponding decrease in odor offensiveness
occurred. Table 11 gives moisture content of wastes from
four species.

Livestock manures usually contain 70 to 83 percent
moisture and can be handled in this semisolid form. How-
ever because of high labor requirements and lack of satis-

factory solids handling equipment, many operations add

38

TABLE 11

Moisture Content of the Manure and Feces
of Selected Domesticated Animals

 

 

Moisture (%) fecesa Moisture (%) manure*b
Cow 83 85
Poultry 72 72
Swine 67 82
Sheep 74 77

*Fresh mixed manure and urine

 

aSource: E. E. Geldreich (1966).

bSource: S. A. Hart (1960).

moisture to manure and handle as a liquid. Using this sys-
tem, wastes of over 90 percent water can be transported

by pumps, spreader or irrigation equipment, but total
volume is correspondingly increased (Loehr, 1974).

When moisture content is below 90 percent the
manure usually must be scraped and handled as a semisolid
or solid. Both liquid and semisolid forms of the manure
will produce odors, but if 80 to 90 percent of the moisture
is removed, no malodors will be produced (Loehr, 1974).

Sobel (1969) gives two possible methods for removal
of water from manure. These are: (l) mechanical - a source
of energy must be provided and (2) thermal - a natural
source of energy can be used but climate is not always
adequate. These methods will reduce the weight and volume

of the manure. Sobel (1971) reported that the ideal

39

moisture content for storage of chicken manure was 10 to
15 percent. He further stated that the drying process is
expensive and should only be used if there is an available
market for the dried product.

Another method used to change the character of
manure is to add a substance such as straw or sawdust to
absorb some of the water (Sobel, 1969). This yields a
product that can be handled as a solid, but there is
still some odor problem.

Ifeadi et a1. (1975), using an odor panel, compared
odors of undiluted dairy manure (70 percent feces and 30
percent urine) and diluted dairy manure. This sensory
evaluation indicated diluted dairy waste had a lower
threshold level than undiluted manure. Therefore, the
diluted waste needed a larger volume of air to render the
volatiles odorless indicating the undiluted manure was not
as offensive.

The removal of water from manure seems to be an
effective way of preventing odor production by creating an
aerobic environment. Cost and unsatisfactory climates for
drying are two major problems encountered when using this

technique as a means of odor control.

Effect of pH on Odor Production

 

The pH of manure influences the type of compounds
transferred to the air since pH determines the degree of

ionization. Ionized species have no vapor pressure and

40

will not contribute to odor since a vapor pressure is
necessary for volatilization. Only compounds in the non-
ionized form will be volatile.

The pH at which half of a compound is present in
the nonionized form is called the pKa. The pKa for some
of the compounds produced from decomposing manure is shown

in Table 12.

TABLE 12

pH Values at Which Various Odorous Compounds
are 50 Percent Ionized at 25°C

 

Acidic Compounds pH Basic Compounds pH

 

 

Acetic acid 4.75 Ammonia 9.25
Butyric acid 4.83 Dimethylamine 10.73
Hydrogen sulfide 7.04 Ethylamine 10.81
Propionic acid 4.87 Methylamine 10.66
Trimethylamine 9.81

Source: R. C. Weast (1972).
Earth et a1. (1972) showed the relationship between

pH and the volatility of a compound.

They observed that

for the acidic compounds a pH less than the pKa value

would cause more than 50 percent of the compound to be in

the volatile form while a pH of more than the pKa of the

basic compounds would have the same result.

this relationship is shown in Table 13.

An example of

As the pH increases the amount of sulfide found in

the volatile form declines.

At a pH of 10 or over, there

41

TABLE 13

Relationship of H S in Water at 25°C
as a Fungtion of pH

 

 

pH Fraction of sulfide present as H28
5.0 .99

6.0 .89

6.5 .71

7.0 .44

7.5 .20

8.0 .072

9.2 .0049

 

Source: American Public Health Association (1972).

would be essentially no H28 produced, but at a pH of 5 or
below almost all of the sulfide would be present as H28.

The pH of manure varies with buffering capacity,
moisture content, type of substrate, etc. Miner (1971)
describes the net result of organic degradation during the
early phases as a conversion of many insoluble raw materials
into soluble intermediates. This produces a sufficient
concentration of organic acids to depress pH, and may allow
changes in the dominant types of microorganisms.

According to Miner (1971) a pH from 6.5 to 8.5
favored growth of bacteria over that of fungi and yeasts.
Acid conditions usually favored fungi, but some bacteria
survived. Certain of the Lactobacilli produce lactic acid
that will lower the pH to 5 or less, and thus prevent
growth of certain other bacteria. This condition has been

observed in manure from dairy cows fed silage.

42

Effect_of Temperature on
OdOr Production

 

 

All biological processes are temperature sensitive.
Bacterial cell growth and enzyme activity have more
activity at an optimum temperature and decrease as the
temperature changes from that. Therefore in the winter,
odor production is decreased due to slow degradative pro-
cesses.

In addition to controlling the rate of degradation,
temperature along with pH, dictates the fraction of total
ammonia concentration that is in the NH3 form. Miner (1974)
developed Table 14 showing the percent of total ammonia as

volatile NH3 at different temperatures and pH.

TABLE 14

Fraction of Total Ammonia Concentration
Present as NH as a Function of
Temperagure and pH

 

Temperature (°C)

 

PH 10 20 30
7 0.0018 x 0.0040 . 0.0081
8 0.018 0.038 0.075
9 0.22 0.30 0.45
10 0.65 0.80 0.89

 

Source: J. R. Miner (1974).

At all four stated pH values an increase in tempera-
ture increases the fraction of total ammonia present in

the volatile form. At pH values less than 7.0 there is no

43

significant volatilization of ammonia and at 10 or above

the largest part of the ammonia is in the volatile form.
These observations show that pH and-temperature

will have a direct effect on the type and amount of com-

pounds volatilized either by affecting rate of decomposition

or by determining the amount of the nonionized compound

present.

Aeration as a Means of Controlling Odors

 

One of the most common ways to prevent formation
of malodors from anaerobic decomposition is to aerate the
system. Aerobic bacteria require oxygen as a hydrogen
acceptor, while anaerobic bacteria can use carbon dioxide,
nitrates, sulfates or organic compounds. These plus other
products of anaerobic fermentation are involved in the odor
produced.

Jones et al. (1970) describe aerobic treatment of
livestock waste as being feasible for odor control and also
cite other advantages. These are: (1) partial decomposi-
tion of volatile (organic) solids into water and odorless
gases such as carbon dioxide, (2) destruction of most
pathogenic organisms, (3) reduction in the pollutional
characteristics of the wastes and (4) concentration of the
minerals which may be more readily applied to land.

Jones et a1. (1970) mentioned two types of systems
for aerating animal wastes. One application was an oxi-

dation ditch of two main parts--a continuous Open-channel

44

ditch with an aeration rotor that circulates the ditch
contents thereby providing oxygen. A second type of
aeration system was an aerobic lagoon either naturally or
mechanically aerated. Naturally aerated lagoons depend
upon algae to provide the oxygen necessary for aeration.
Therefore a large surface area is necessary. Mechanically
aerated lagoons utilize equipment that beats or blows air
into the water so that they are not dependent on natural
aeration.

Dale (1971) states that the oxidation ditch has
little promise for treatment of dairy cow waste. Two
problems encountered are excessive foaming and settling of
undigested feed particles which restrict the flow of the
oxidation ditch and the precipitated mass then becomes
anaerobic. A mechanically aerated lagoon would be more
applicable to dairy waste because foaming and precipitation
are not problems (Dale et al., 1969).

The main purpose of an oxidation ditch is to
degrade organic solids. Ogilvie and Dale (1971) suggested
that this degradation could occur just as easily in the
soil without a costly input of energy. They proposed short
term aerobic treatment of dairy cow waste to remove the
odorous components after storage under anaerobic conditions
just before applying to the land. The odors are usually
not a problem during storage, but are when the wastes are

spread on fields. Therefore short term aeration (24 hours)

45

can be used to oxidize the reduced organic compounds before
spreading. Thus in this type of anaerobic-aerobic system
no breakdown of solids is desired because the main purpose
would be odor control.

Chemical‘Addition as a Means of
Controlling Odor

 

 

All Operations cannot conveniently aerate their
animal wastes, and therefore alternate methods are often
needed. One practice is to alter or stop anaerobic
microbial degradation by the addition of a chemical.
Another principle is to chemically oxidize malodors to
allow sufficient time for field spreading of the wastes.
Still another principle alters the decomposition pathway
to allow production of less objectionable odors. Addi-
tionally masking agents, counteractants and deodorants
have been utilized in decreasing the offensiveness of

manure odors.

Lime

 

Yushok and Bear (1948) added hydrated lime to
poultry manure at 5 and 20 percent of total volume and
found it effectively deodorized as well as reduced nitrogen
loss. They argue that since most soil can benefit from
liming, this method has no direct cost for odor control.
Deibel (1967) found that the addition of lime to liquid
poultry manure abated odor for seven to ten days after

which time the smell of ammonia became very strong.

46

By maintaining the pH between 9 and 10 with lime,
Hammond et a1. (1966) suppressed odors from liquid hog
manure. They used about 0.15 pound of hydrated lime per
100 pound hog per day which reduced production of hydrogen
sulfide, but did not prevent ammonia formation.

Day (1966) kept the pH of liquid hog manure between
9 and 11 using lime. Whenever the pH dropped to 9, more
lime was added. This treatment effectively eliminated
odors probably by inactivating anaerobic bacteria. The
amount of lime needed was 0.16 pound per 100 pound pig
'per day.

Cole et al. (1974) found lime did not improve
swine manure slurry odor when the pH was maintained above
11. Also there was no noticeable reduction in sulfide
levels in the manure, but a strong ammonia odor developed
as a result of the increased pH.

There have been several conflicting reports as to
the effectiveness of lime in decreasing nitrogen loss and
the offensiveness of manure odor. One report indicated a
decrease in nitrogen loss while several other reports
stated an increase in the amount of ammonia volatilized to
the atmosphere with a resulting increase of ammonia odor.
This would seem to be inconsistent because ammonia repre-
sents a loss of nitrogen, and lime produces conditions
favorable for ammonia volatilization. Also an increased

ammonia odor would tend to add to the offensiveness in

47

many instances, although it may be more desirable than

many of the other degradation products.

Sodium Hydroxide

Sodium hydroxide (NaOH) at 0.9 percent of total
volume was found effective in preventing the development
of malodors for 28 days from poultry dropping slurry
(Benham, 1967). This treatment also reduced total aerobic
bacteria and coliforms. Application of the equivalent of
6,000 gallons of liquid poultry manure containing 0.8
percent NaOH per acre of grassland had no deleterious
effect on the vegetation.

NaOH would tend to act in much the same way as
lime in raising the pH of the manure. If this were the
case ammonia loss could be a problem when using NaOH as a

means of controlling odors.

Chlorine

According to Loehr (1974) chlorine is an oxidizing
agent capable of reacting with organic waste matter,
reduced inorganics (H28 and NH3) and microorganisms. Many
of the reactions compete with the use of chlorine for dis-
infecting purposes. The hypochlorite salts are one of
the more common forms used in animal waste treatment, and
are dissociated in solution to yield free ion (Na+) and

hypochlorous acid (HOCl).

48

Hammond et a1. (1966) used calcium hypochlorite
(Ca(OCl)2) to treat liquid swine waste in a confinement
unit. For effective odor control they found 0.1 pound of
active chlorine per 100 pound hog per day was needed and
concluded that odor reduction was a result of the anti-
microbial action of chlorine.

Deibel (1967) added hypochlorite to liquid poultry
waste, and caused the evolution of chlorine gas. This
process is probably a result of the reaction of hypochlorite
and uric acid. The chlorine treatment substantially
reduced ammonia, hydrogen sulfide, methane and carbon
dioxide production.

Swine pit contents of fecal matter and urine were
treated with varying levels of sodium hypochlorite (NaOCl)
and chlorine dioxide (C102). Sulfide concentration in the
manure dropped to very low levels within 15 minutes, but
neither treatment had any significant effect on ammonia
concentration. An odor panel evaluated the treatments and
found 500 PPM of both compounds to be the most effective
level to reduce odor (Cole et al., 1975).

Liquid dairy manure was similarly evaluated (Cole
et al., 1975). Sulfide concentration in the manure was

reduced only about half for NaOCl and C10 at 250, 500 and

2
1000 PPM with no improvement in odor. This is in contrast
to what the authors observed for swine manure where

sulfide concentration was reduced by more than 90 percent

49

with a corresponding depression in odor strength. Their
explanation is the odor panel judged the liquid dairy manure
as being less strong and offensive than swine manure
meaning there would probably not be as great a reduction

in odor from dairy manure. Also total solids of the dairy
manure was greater than the swine manure. Thus effective-
ness of odor treatments may vary withssolids content and
relative odor offensiveness.

Results indicate that hypochlorite salts can be a
feasible means of odor control for liquid swine and
poultry waste. Effectiveness in liquid cattle waste is
inconclusive because of limited data.

Paraformaldehyde and
Formaldehyde

 

 

Paraformaldehyde was described by Seltzer et a1.
(1969) as being a mixture of polyoxymethylene glycols
containing 90-99 percent polymerized formaldehyde, and is
available in powder, granule and flake form.

Paraformaldehyde liberates formaldehyde gas as it
depolymerizes. According to Seltzer et a1. (1969) increased
temperature will cause an increase in the rate of depoly-
merization. This formaldehyde is then free to react with
ammonia to form the compound hexamethylenetetramine
(C6H12N4) which is a white, powdery, nontoxic, odorless

substance.

50

Seltzer et a1. (1969) used 0.5 up to 7 grams
paraformaldehyde per 100 grams of fresh liquid poultry
manure to determine the effect on obnoxious gas formation.
The pH of the headspace over the manure was used to esti-
mate ammonia production. Paraformaldehyde addition of 3
grams or above prevented ammonia production for 28 days,
while addition of 0.5 and 1 gram prevented ammonia pro-
duction for about one week. However after this week,
levels were similar to control. Control manure developed
a noticeable ammonia odor within 24 hours and reached a
maximum pH of 11 within 48 hours indicating over 100 PPM
ammonia. Bacterial counts made after 12 days indicated
the addition of 1 gram paraformaldehyde lowered number of

9 to 108 when compared

to control. Addition of 3 grams decreased counts to 103,

organisms per gram of manure from 10

while manure with 7 grams had no organisms. They concluded
that the mode of action of paraformaldehyde on animal
wastes was both chemical and antimicrobial.

After 28 days Seltzer et al. (1969) found
increasing levels of nitrogen retained in poultry manure
as level of paraformaldehyde increased. They also noted
no indication that mortality or other symptoms of toxicity
increased in poultry when litter was treated with para-
formaldehyde. Flies when given a choice deposited eggs in
control manure instead of manure treated with paraformalde-

hyde.

51

Paraformaldehyde added at one and three percent to
poultry litter reduced bacterial counts to 10 percent of
control, and mold counts to 1 percent of control (Veloso
et al., 1974). The pH of the litter was slightly reduced
for three weeks with the three percent treatment. No
difference in the nitrogen retention was observed.

Sobsey et a1. (1974) found the ability of formalde-
hyde to disinfect sewage improved as the pH was raised from
8 to 10.5. The biodegradability of formaldehyde gives
this compound some advantage over other disinfectants.

At low concentrations formaldehyde can serve as a substrate
for bacteria, and therefore will not accumulate in the
soil upon spreading.l V

Formaldehyde slightly reduced sulfide concentration
in liquid dairy manure, but no decrease in odor was noted
(Cole et al., 1975).

Ulich and Ford (1975) used an odor panel to evalu-
ate the effectiveness of sprinkling paraformaldehyde flakes
on the surface of beef cattle manure. The slight decrease
in both odor offensiveness and strength was not sufficient
to be economical. .

Paraformaldehyde has been shown to be adequate in
reducing ammonia release. In situations where ammonia
concentrations in the air reach problem levels, such as in
poultry houses, this technique can be applied. Results

using formaldehyde or paraformaldehyde on cattle manure for

52

odor control is limited, but seems to be either ineffective

or uneconomical.

Potassium Permanganate

 

Miner (1974) classified potassium permanganate
(KMnO4) as a powerful oxidizing agent that is most effective
in acid solutions and least effective in neutral solutions.
The reactivity of KMnO4 will generally increase with
increasing temperature and increasing concentration of
oxidizable impurities.

A one percent KMnO4 solution sprayed on a feedlot
at the rate of 20 pounds of KMnO4 per acre was more
effective in controlling odors than some counteractants,
masking agents and disinfectants tested at the same time
(Faith, 1964).

Miner and Stroh (1975) applied KMnO4 at the rate
of 20 pounds per acre in a one percent solution to portions
of a beef cattle feedlot. Ammonia evolution rates from
selected portions were similar to that in untreated portions.
To evaluate the effect on odor production a scentometer
was used to determine the dilutions to threshold. No
difference could be detected between the KMnO4 and untreated
areas.

Ulich and Ford (1975) found KMnO4 to be effective
in the suppression of odorous gases applied at the rate of
56 pounds per ton of beef manure. Upon further testing an

odor panel determined 20 pounds per acre would be adequate.

53

KMnO4 (100 to 500 PPM) adequately mixed with liquid
swine manure caused a decrease in the sulfide concentration
in the waste (Cole et al., 1975). When compared to other

chemical oxidants KMnO was least effective in reducing

4
sulfide concentrations at one-half hour, but was most
effective after a few days indicating a long term depression
of odor. No change in ammonia concentration in the waste
was observed. An odor panel rated the 500 PPM level as

the best concentration for reducing odor strength.

At 250 to 1000 PPM KMnO4 showed no substantial
decrease in sulfide or ammonia concentrations in liquid
dairy manure (Cole et al., 1975). An odor panel detected
no odor reduction.

Ritter et a1. (1975) mixed KMnO4 with liquid dairy
manure to reduce malodors. More than 90 percent of an odor
panel found the treated manure to be "not offensive" or
"mildly offensive" one hour after treatment. This was
still true 24 hours after treatment. They conclude that
KMnO4 reduces odors from liquid dairy manure for at least
72 hours. t

The results indicate‘KMnO4 may be adequate in
reducing offensiveness of liquid swine and dairy manure
as well as beef feedlot manure, but some reports are con-

tradictory. Further research under more controlled con-

ditions is needed.

54

Hydrogen Peroxide

 

Hydrogen peroxide (H202) is an oxidizing agent
commercially available as an aqueous solution ranging from
three to 98 percent (Miner, 1974). Solutions greater than
eight percent are corrosive and must be handled with care.
In natural systems H202 can be broken down to water and
molecular oxygen.

Hollenbach (1971) added a 50 percent H202 solution
to a liquid dairy manure pit to a concentration of 100 PPM
H202 using a circulating pump. When the pump was first
started and before any H202 had been added, a sulfide odor
was evident and air sulfide concentration increased. Upon
addition of H202 no sulfide odor could be detected and only
a slight odor remained after 18 hours of nonagitation.

The hydrogen sulfide odor returned to previous level
after reagitation.

In a similar trial Hollenback (1971) treated a
liquid manure pit with a 50 percent H202 solution. Immedi-
ately after the first 100 PPM was added, a second 100 PPM
dose was given. This additional H202 resulted in a further
decrease in the odor from the manure. Sixteen hours later
the sulfide level had returned to the level prior to treat-
ment. Foaming difficulties were reported in the second
trial.

O'Neill (1972) added varying levels of 10 to 15
percent H202 to liquid dairy manure. At 50 PPM H

202

55

there was only limited success in odor control, but the
sulfide odor was eliminated. At 125 PPM H202 only a silage-
like odor was noticed. Originally sulfide was present in
the liquid manure at levels greater than 5 PPM, but were
reduced to zero by treatments of over 100 PPM H202. No
foaming occurred.

Pig manure slurry was treated by O'Neil (1972)
with 10 percent H202 to develop 115 and 275 PPM. Both
levels reduced hydrogen sulfide levels to zero in the
atmosphere over the slurry. The lower level was thought
to be superior to the higher level probably due to
improper mixing at the 275 PPM level.

Kibbel et a1. (1972) added H202 at 100, 150, and
175 PPM to chicken manure slurry. This manure was spread
on the land in strips according to treatment. Hydrogen
sulfide was reduced to almost zero at all treatment levels
of H202, and a resulting decrease in odor offensiveness
occurred. The odors remained suppressed in the H202
treated plots compared with the control for the second and
third day after application.

,Ritter et al. (1975) added fresh bovine feces to
liquid dairy pit manure over a six week period. After this
period H202 was added. The minimum amount of H202 needed
to eliminate the hydrogen sulfide was determined to be
12.5 PPM. This also increased dissolved oxygen content

of the manure proportionally to the amount of H20 added.

2

56

Although the hydrogen sulfide was destroyed for a short
period of time other malodors remained.

The effect of adding 30,000 PPM H202 to fresh
bovine manure was investigated by Ulich and Ford (1975).
Two tests using an odor panel gave contradictory results,
but H202 reduced the release of sulfurous gases.

Cole et al. (1975) found that sulfide concentration
in liquid swine manure was reduced to less than 1 PPM with
doses of 300 and 500 PPM H202. Ammonia concentration was
not changed. An odor panel found odor strength to be
reduced at 300 and 500 PPM H202. 0f the chemicals evalu-
ated H202 was the most economical for prevention of odor
problems.

Slight reduction in the sulfide content of liquid
dairy manure with no reduction in the odor was noted with
250, 500, and 1000 PPM H202 (Cole et al., 1975). This is
in contrast to what they observed in liquid swine manure.
The solids content was higher in the liquid dairy manure
perhaps indicating need of a larger dose of H202 to achieve
results similar to the effectiveness in swine manure.

Most reports indicate H202 acts to decrease sulfide
concentrations, but not all are certain if there is a
corresponding decrease in odor offensiveness. Use of

H202 may be satisfactory in some circumstances where

foaming does not occur for at least partial odor control.

57

Masking Agents, Counteractants,
Deodorants and Digestive
Deodorants

 

 

 

These types of compounds are available commercially
for the control of livestock odors (Miner, 1974). The
masking agents have an acceptable odor designed to over-
come the manure odor. Counteractants tend to cancel the
odor of the waste. Deodorants destroy or eliminate the
odorous components of the waste. The digestive deodorants
are a combination of enzymes and bacteria used to change
the degradation process so as to alter the production of
odorous compounds.

The effectiveness of these four types of prepara-
tions was tested for odor control using liquid poultry
manure by Burnett and Dondero (1968). An odor panel
evaluation provided an index of comparison between treated
and untreated manure. Masking agents and counteractants
were the most effective in controlling odors with deodorants
moderately effective. The digestive deodorants were least
effective.

A dried bacterial and enzyme product was applied
as a spray to the surface of a beef feedlot by Miner and
Stroh (1975). The initial application was 10 pounds per
acre. There tended to be a reduction in ammonia release
from the surface. Scentometer evaluation five days after

the initial treatment showed the treated area had a

58

measurably less intense odor than the control. Ten days
after initial treatment no difference was detectable.

Jongebreur and van Geelen (1974) reported that a
masking agent added to the air, gave effective control of
manure odors from chicken and swine buildings. A counter-
actant was also effective in a poultry Operation when added
to the air. The authors doubted that inhabitants near
livestock confinement areas would accept the smell of the
treatments, especially that of the masking agent.

Concentrations of sulfide and ammonia along with
odor strength were monitored for 56 days after swine and
dairy pit manure were treated with commercial dried
bacteria and enzyme preparations (Cole et al., 1975). No
reduction in any of the three were found, and they concluded
that these experiments do not substantiate the manufacturer's
claims.

Ritter et al. (1975) evaluated the effect of a
masking agent as well as several dried bacterial and enzyme
preparations on odor offensiveness in liquid dairy pit
manure. The digestive deodorants were added and evaluated
after 48 hours. The masking agent was added one hour before
evaluation. The odor panel indicated that only one of the
digestive deodorants was effective in reducing odor
offensiveness. The masking agent was found adequate for

control of odor.

59

Masking agents and counteractants appear to be the
most efficient of these compounds in controlling odor.
Yet, masking agents can become so strong that they become
offensive when present at sufficiently high concentrations
(Taiganides and White, 1968). Also large quantities of
masking agents are needed to overpower the odor from
animal waste making their use expensive. The counter-
actants are specific for certain odors yet very few of
these counteracting pairs have been identified. Since
odor from animal waste is made up of many components
finding a counteractant to each appears almost impossible.
The deodorants and digestive deodorants appear to have
limited applicability for control of odors from livestock

operations.

(BEBE

Potassium nitrate (Ulich and Ford, 1975) and sodium
nitrate (Cole et al., 1975) have been tested in odor pre-
vention trials. Nitrate supplies a hydrogen acceptor so
that the redox potential of the waste pit will not permit
formation of odorous compounds. Potassium nitrate reduced
strength and offensiveness of odor from bovine manure,
however, it was an expensive method. Sodium nitrate
reduced sulfide content of liquid swine and dairy manure
but no decrease in odor strength was detected.

Deibel (1967) used direct ozone treatment in an

attempt to oxidize odors in liquid poultry manure. No

60

reduction in odor was detected. Another technique involved
adding ozone directly to the air inside a confinement
building in an attempt to oxidize the malodors in the
atmosphere (Haye, 1973). A reduction in odor was observed,
but ozone can be harmful to animals and humans at low
concentrations.

Orthodichlorobenzene was found by Cole et a1. (1975)
to be ineffective in reducing sulfide concentration in
liquid swine and dairy manure. Also no reduction in odor
was detected. On the other hand, Ulich and Ford (1975)
observed that orthodichlorobenzene suppressed release of
sulfurous gases in beef manure slurries and reduced odor.
These authors concluded that it would be an economical
method to control cattle feedlot odors during wet periods.

Sodium bentonite has been tested by Miner and
Stroh (1975) for reducing odor from cattle feedlot surfaces.
Sodium bentonite reduced ammonia release and odor intensity
of the lot surface.

Activated carbon was added to both liquid swine
and dairy manure to serve as an absorbent for malodors by
Cole et a1. (1975). Sulfide concentration was reduced
in liquid swine slurry plus a slight decrease in odor
strength. However in liquid dairy manure sulfide concen-
tration was only slightly reduced with no reduction in

odor.

61

Management as a Means of Controlling Odor

 

Under most conditions proper management can prevent
the release of odors into the atmosphere so as not to be
offensive to neighbors. Miner (1970) listed several
principles that minimize odor. These are: (l) locate
livestock operations away from residential areas, (2) keep
feeding areas and animal pens dry, (3) design the system
to prevent animals from becoming dirty and manure-covered
and (4) prompt disposal of dead animals.

Gases produced during manure storage can present a
problem. Location of storage tanks outside of livestock
buildings reduces hazards to the animals from gas release
upon mixing, but increases problems associated with move-
ment of manure to the storage tank.

Spreading animal waste on land allows malodors to
be released often resulting in complaints from neighbors.
One way to prevent this is to inject the manure several
inches under the soil surface (Dale, 1971). This method
is applicable only when soil is in a workable condition,
and cannot be used when soil is wet or when most crops
are being grown.

When manure is applied directly on the surface of
soil, as is usually the case, timing and site selection
are two important criteria (Conner et al., 1971). Manure
should not be spread so that the wind will take the odor

to the neighbors, and if possible manure should be applied

62

at a distance so that the odor will dissipate before
reaching anyone.

The control of odor from animal wastes has been
approached from several directions. If foresight is used,
most odor problems can be prevented by proper management
techniques, but with the encroachment of suburbs into
agricultural areas, many farmers find themselves with
nonrural neighbors. Under these conditions proper manure
management is essential. Since odors are usually only a
problem during and after spreading addition of certain

chemicals may offer short term odor control.

III. MATERIALS AND METHODS

Experiment I

 

Feces and urine were collected, pooled separately
and each mixed before adding 63 percent fresh dairy cow
feces, 27 percent urine and 10 percent water to 1.9 liter
glass jars. Jars were used to simulate manure pits.
Chemicals were added and thoroughly mixed to form the
following concentrations in parts per million (PPM):
paraformaldehyde (7000; 10,000; 30,000), acrolein (l and
100), phosphoric acid (657; 1000; 10,000), sodium per-
chlorate (250; 500; 2000), hydrogen peroxide (75; 150; 300)
or potassium permanganate (250; 500; 1000). Paraformalde-
hyde (Vineland Poultry Laboratories, Vineland, N.J.) and
sodium perchlorate (source unknown) were added as a powder,
potassium permanganate (Mallinckrodt Chemical Works, St.
Louis, MO) as crystals, acrolein (Eastman Kodak Co.,
Rochester, N.Y.) and phosphoric acid (Mallinckrodt Chemical
Works, St. Louis, MO) as a liquid and hydrogen peroxide
(Mallinckrodt Chemical Works, St. Louis, MO) as a 30 per-
cent solution. All treatment levels were done in dupli-

cate .

63

64

The large number of jars required two trials.
Experiment la compared paraformaldehyde, acrolein and
phosphoric acid while Experiment lb compared sodium per-
chlorate, hydrogen peroxide and potassium permanganate.
All jars were stored at approximately 20°C.

Determination of Total Aerobic
and Anaerobic Microorganisms

 

 

A sample was taken from one jar of each duplicate
at the highest and lowest level of treatment at l, 8, 15
and 22 days after addition of chemicals. Jar contents
were mixed with a sterile metal spatula and a sample was
placed in a sterile glass baby food jar for transportation
to the laboratory. This sample was placed in a known
volume of sterile distilled water to make an approximate
1:10 dilution which was mixed in a sterile blender (Waring
Commercial Blender) for two minutes. One ml of the sample
was placed in nine ml of sterile distilled water in dup-
licate. A serial ten-fold dilution was done to eight
tubes using sterile one ml pipettes. Sterile Pasteur
pipettes were used to transfer one drop, calibrated at 1/35
ml, from each dilution in duplicate into plates of brain-
heart infusion agar. The plate taps were left slightly
open to allow the drops to dry. Each dilution was then
inverted and incubated at 37°C for 24 hours in an aerobic
(Blue M Incubator) or an anaerobic incubator (National

Appliance Co. Incubator). Each sample had 2 series of

65

plates in an anaerobic and 2 series in an aerobic environ-
ment. The lowest dilution that forms distinguishable
isolated colonies (usually 10 to 50 colonies) was counted.
The total count was calculated by the following equation:

total counts _ number of l dilution

per gram — colonies x dilution ofidrOp x factor x 35

Values given were an average of duplicates.

Determination ofng

 

At 2, 7, 14 and 21 days after addition of chemicals,
pH was determined in each jar after complete mixing in
Experiment Ia. Experiment lb was not evaluated at day 14,
but was at 2, 7 and 21 days after addition of chemicals.
This was done by placing the probe from a pH meter

(Sargent-Welch model L S) directly into the manure.

Determination of Total Solids

 

All jars were sampled after treatments were added
and total solids were measured after evaporation of water

at 100°C in a forced draft oven for 24 hours.

Determination of Ammonia in Air

 

Atmospheric ammonia (NH3) was collected and quanti-
fied by methods described by Jacobs (1960) and Miner (1974)
at 2, 7 and 21 days after addition of chemicals. Standard

ammonium chloride solutions containing ammonia

66

concentrations of 12.2 to 366.0 micro grams were used to
construct a standard curve from which unknown concentrations

were calculated.

Odor Panel Evaluation

 

A panel of five people evaluated each jar 4 and 5
days after addition of treatments for quantity (strength)
and quality (offensiveness) of the odor. Each panelist
was given Table 15 for reference and asked to rate each
numbered jar as to strength and offensiveness. No time

limit was set. Manure was agitated before evaluation.

TABLE 15

Odor Evaluation

 

 

Strength Offensiveness
(quantity) (quality)

0 No Odor 0 Not Offensive

2 Very Faint 2 Very Faint Offensiveness

3 Faint 2 Faint Offensiveness

2 Definite 2 Definite Offensiveness

8 Strong 8 Strong Offensiveness

13 Very Strong 1: Very Strong Offensiveness

 

Experiment II

 

Pit contents were removed from the Michigan State
University dairy farm liquid manure pit and after complete

mixing, placed in 1.9 liter glass jars. The contents

67

consisted of dairy cow urine and fecal matter plus water
used to wash the milking parlor and milking apparatus.
Some of the water added to the pit contained detergents.

Jars were randomly assigned to a treatment con-
sisting of varying parts per million of either lime (5000
and 10,000), paraformaldehyde (1000; 5000; 10,000),
hydrogen peroxide (100 and 500) or potassium permanganate
(500 and 1000). Treatments were added directly to the
liquid manure and thoroughly mixed. Lime (United States
Gypsum, Chicago, IL) was added as a powder. All other
treatments were added as in Experiment I and all levels
were done in duplicate.

Determination ofng and
Total Solids

 

 

The pH and total solids were determined as in
Experiment I. The pH was done at -l, l, 4, and 7 days
after addition of treatments.

Determination of Total Ammonia
in the Manure

 

 

A ten m1 sample was taken from one jar of each
treatment level and diluted to 100 ml with distilled water
at day 2 and 10 after addition of chemicals. This was
agitated by a magnetic stirrer to keep all particles in
suspension. An ammonia probe ("Orion" Specific Ion
Electrode) connected to a Beckman digital pH meter model

4500 was placed into the diluted sample and ten drops of

68

10 M NaOH was added to convert NH4+ to NH3 to which the
electrode is sensitive. Standard solutions of ammonium
chloride containing 14 and 140 mg per liter ammonia were
used for construction of a standard curve. Ammonia con-
centrations of the unknown samples were calculated from

the standard curve, and results were expressed as total

ammonia (NH3 and NH4+).

Nitrate Determination

 

Each treatment level was tested for the presence
of nitrates. A drop from each level was added to the well
of a spot plate. To this a drop of diphenylamine was
added and a blueish ppt. indicated the presence of nitrates.
A standard nitrate solution (0.1 mg/ml) was used as a

reference, and color intensity estimated visually.

Odor Panel Evaluation

 

An odor panel of three people evaluated each jar
l, 3 and 8 days after addition of treatments. The pro-

cedure was the same as is described in Experiment I.

Experiment III

 

Liquid pit manure was obtained as in Experiment II
and placed in an Open 55 gallon barrel. To this was added
fresh fecal matter and urine from lactating dairy cows.
This mixture remained at ambient temperature for one
month, then mixed and portions were added to 1.9 liter

glass jars.

69

Jars were randomly assigned to a treatment con-
sisting of lime (5000 and 10,000 PPM), paraformaldehyde
(1000; 5000; 10,000 PPM), hydrogen peroxide (100 and 500
PPM) or potassium permanganate (500 and 1000 PPM). Com-
pounds were added as in Experiment I and II, but treatment
levels were in triplicate.

Determination of Total Aerobic
Microorganisms

 

 

After 1 and 8 days, a sample was taken from one
jar of a triplicate at the highest and lowest level of
treatment. The procedure for total aerobic microorganisms
was the same as in Experiment I.

Determination of pH and
Total Solids

 

 

Total solids and pH were determined as in
Experiment I. The pH was determined at -1, 1, 4 and 9
days after addition of treatments.

Determination of Total Ammonia
in the Manure

 

 

At days -2, 4 and 11, ammonia (NH3 and NH4+) was

determined as in Experiment II.

Odor Panel Evaluation

 

An odor panel of five people evaluated each jar
l, 2 and 8 days after treatments were added. The pro-

cedure was as in Experiment I.

70

Experiment IV

 

Several gallons of manure from the liquid manure
pit at the Michigan State University dairy farm was placed
in an open 20 gallon plastic container and fecal matter
and urine from lactating dairy cows added. This mixture
remained at room temperature for one month at which time
contents were mixed and added to 1.9 liter glass jars.

Jars were randomly assigned to a treatment con-
sisting of varying PPM of either paraformaldehyde (5000
and 10,000), potassium permanganate (500 and 1000) or
hydrogen peroxide (100 and 500). Treatments were added

as in Experiment I.

Determination of Total Solids

 

Total solids were determined from various selected

jars as in Experiment I.

Odor Panel Evaluation

 

An odor panel of at least six pe0ple was used to
compare treatments and treatment levels to a control.
Each panelist was allowed to evaluate three jars of which
one was a control and told to detect which one was least
offensive and which was most offensive. Combinations of
treated manure in each comparison (besides control) were
paraformaldehyde 5000 vs. 10,000 PPM; potassium permanganate
500 vs. 1000 PPM; hydrogen peroxide 100 vs. 500 PPM;

paraformaldehyde 5000 PPM vs. potassium permanganate 500

71

PPM; paraformaldehyde 5000 PPM vs. hydrogen peroxide 500
PPM; potassium permanganate 500 PPM vs. hydrogen peroxide
500 PPM. Comparisons were at three time periods: 9 to 15
hours, 36 to 40 hours and 8 days. Hydrogen peroxide at
100 vs. 500 PPM and hydrogen peroxide at 100 PPM vs.
potassium permanganate at 500 PPM, were compared together

against a control at 0.5 to 1.5 hours, 7 hours and 9 days.

Experiment V

 

Manure used in this experiment was taken from the
same source as Experiment IV before addition to 1.9 liter
glass jars. Treatments were added and thoroughly mixed to
form the following concentrations in PPM: Sep-Zyme "O"
(360), Pit-Zyme (360) and Odor Mask (1430). Sep-Zyme "O"
(Sep-Ko Chemicals, Minneapolis, MN) and Pit-Zyme (source
unknown) were added as a powder while Odor Mask (The Kalo

Co., Quincy, IL) was added as a liquid.

Determination of Total Solids

 

Total solids were determined from various selected

jars as in Experiment I.

Odor Panel Evaluation

 

An odor panel of at least eight people was used to
evaluate treatments as in Experiment IV. Combinations of
treated manure in each comparison (besides control) were

Odor Mask vs. Pit-Zyme, Pit-Zyme vs. Sep-Zyme "O" and

72

Odor Mask vs. Sep-Zyme "0". Comparisons were at three

time periods: 9 to 15 hours, 33 to 39 hours and 8 days.

Statistical Analysis
Data from Experiment I, II and III were analyzed
with the Bonferroni t-Test (Miller, 1966) by comparing
means within each time period. Rankings from Experiment IV
and V were analyzed by the Wilcoxon Matched-Pairs Signed-

Ranks Test (Siegel, 1956).

IV. RESULTS

Experiment I

 

Manure (feces and urine) used in this experiment
was taken directly from lactating dairy cows and put into
jars along with water. This manure will be referred to as
fresh manure because no decomposition occurred before
addition of chemicals. This manure averaged about 13 per-
cent dry matter, a value somewhat above that of most

"liquid manures."

Microbial Counts

 

Paraformaldehyde, acrolein and phosphoric acid
(H3PO4) added to fresh dairy manure produced responses in
numbers of aerobic and anaerobic microorganisms shown in
Table 16. Paraformaldehyde at 7,000 and 30,000 PPM
markedly reduced total aerobic and anaerobic counts through-
out the 22 day trial when compared with control. Acrolein
at one and 100 PPM may have slightly reduced both aerobic
and anaerobic counts. Aerobic and anaerobic counts were
PO

reduced at day one through 15 by 10,000 PPM H but by

3 4’

day 21 values were similar to control.
Microbial numbers after addition of sodium per-

Chlorate (NaClO4), hydrogen peroxide (H202) and potassium

73

74

TABLE 16

Aerobic and Anaerobic Microbial Numbers1 at Four
Intervals After Three Chemicals were Added
to Fresh Liquid Dairy Manure
(Experiment Ia)

 

 

 

. DEX,
Chemicals and Levels 1 8 15 22
Aerobic Counts
Paraformaldehyde (PPM) 4 4 4 4
7,000 47x104 4x104 2.5x10 1.2x10
30,000 31x10 0.69x10 0.25x10 0.16xlO
Acrolein (PPM) 7 7 7 7
1 6x10 22x10 . 59x10 5.1x10
100 3.5x10 5.1x10 28x10 8.3xlO
Phosphoric Acid (PPM) 7 7 7 7
657 6.9x10 32x107 13x10 22x10
10,000 0.03x10 35x10 31x10 33x10
Control 7.8x107 140x10.7 73x107 35x107
Anaerobic Counts
Paraformaldehyde (PPM) 4 4 4 4
7,000 410x10 4x104 0.7x104 0.49x104
30,000 100x10 0.5x10 0.17x10 0.16x10
Acrolein (PPM) 7 7 7 7
1 9x10 10x10 96x10 6.3x10
100 7.2x10 9.3x10 0.98x10 12x10
Phosphoric Acid (PPM) 7 7 7 7
657 8.3x107 6.3x107 13x10 19x10
10,000 0.3xlO 55x10 50x10 91x10
Control 5.2x107 290x107 22x107 9.7x107

 

1Each value an average of duplicates taken from the same jar
expressed as microorganisms per gram of treated manure.

75

permanganate (KMnO4) to fresh dairy manure are presented

in Table 17. NaClO4 at 2000 PPM reduced total aerobic

and anaerobic counts for eight days, but by day 16 counts
were similar to control. NaClO4 at 250 PPM, H202 at 75 and
300 PPM andKMnO4 at 250 and 1000 PPM did not alter counts
from control values.

The relationship between aerobic and anaerobic
microorganisms was such that none of the treatments resulted
in a change in one without a concurrent and similar change
in the other.

Table 16 and 17 have different control values
because they were done at two different time periods, and

no statistical evaluation could be made because there was

only one jar per value.

93
Table 18 presents the relationship of paraformalde-
hyde, acrolein and H3PO4 treatment to pH with time. At
day two the pH group mean for paraformaldehyde was less
than control (p < .005), with no difference between concen-
trations although there was a tendency for pH to decrease
with increasing concentration of paraformaldehyde. The
pH group mean for paraformaldehyde was still less than
control (p < .05) at day seven, but at day 14 and 21 no
differences were detected.
The pH of acrolein treated manure was not different

than control at any day tested. At day two the pH group

Aerobic and Anaerobic Microbial Numbers1

76

TABLE 17

at Four

Intervals After Three Chemicals were Added

to Fresh Liquid Dairy Manure
(Experiment Ib)

 

 

 

 

. Day
Chemicals and Levels 1 8 15 22
Aerobic Counts
Sodium Perchlorate (PPM) 7 7 7 7
250 30x10 63x10 110x10 91x10
2000 1.7x10 2.5x10 94x10 140x10
Hydrogen Peroxide (PPM) 7 7 7 7
75 40x10 53x10 110x10 110x10
300 44x10 64x10 91x10 41x10
Potassium Permanganate (PPM) 7 7 7
250 48x10 66x10 99x10 82x107
1000 50x10 61x10 93x10 100x10
Control 39x10.7 67x107 110x10 59x107
Anaerobic Counts
Sodium Perchlorate (PPM) 7 7 7 7
250 28x10 79x107 160x10 120x10
2000 1.3x10 0.94x10 170x10 120x10
Hydrogen Peroxide (PPM) 7 7 7 7
75 28x107 74x10 180x10 69x10
300 32x10 90x10 150x10 78x10
Potassium Permanganate (PPM) 7 7 7 7
250 24x107 76x10 91x10 92x10
1000 31x10 66x10 120x10 80x10
Control 28x107 100x107 100x10 73x107
1

Each value an average of duplicates taken from the same jar
expressed as microorganisms per gram of treated manure.

pH

77

TABLE 18

at Four Intervals After Addition of
Three Chemicals to Fresh Liquid Dairy
Manure (Experiment Ia)

 

 

 

. Day
Chemicals and Levels 2 7 'I4 21
Paraformaldehyde (PPM)

7,000 6.35 6.20 6.35 6.40
10,000 6.25 6.00 6.10 6.10
30,000 6.00 5.95 5.95 6.20

I I I iein: I I I I I I I 2622?: I E-ESE I 26:11 I 2622: I
Acrolein (PPM)
1 7.30 6.30 6.10 6.00
100 7.40 6.30 5.80 6.05
I I I fie‘én: I I I I I I I 27:35 I I EEO: I 25:92 I 262.03 I
Phosphoric Acid (PPM)
657 6.90 6.40 5.80 6.20

1,000 6.60 6.45 5.90 6.15
10,000 5.85° 5.85ac 5.75 5.80bd

I I I Ee'én: I I I I I I I 262433: Z 5-23: I 25:82 I 26.7.05 I
Control 7.20 6.35 5.85 6.15
SEM2 .08 .07 .12 .07

 

1Each value an average of two jars.

2

given day.

SEM = standard error of each mean of two jars on a

aSignificantly different (p < .005) than control

within the same column.

bp <

CSignificantly different (p < .005) than means from
lower treatment concentrations within the same treatment
group within the same column.

dp <

78

mean of H3PO4 treated manure was less than control (p <
.005) with pH of the 10,000 PPM treatment being less than
that of the lower two concentrations (p < .005). At day
seven the group mean was not different than control, but
pH of the 10,000 PPM treatment was less than control and
the two lower treatment concentrations (p < .005). At

P0 and

3 4
control, but by day 21 pH of the 10,000 PPM concentration

day 14 no differences were detected between H

was less than control (p < .01) and the two lower treat-
ment concentrations (p < .05). These results demonstrate
pH decreased as H3PO4 concentration increased.

The pH of fresh dairy manure treated with NaClO4,
H202 or KMnO4 with time is presented in Table 19. At day
two no significant differences in treatments could be
detected although NaClO4 tended to increase pH with
increasing concentrations. At day seven pH of manure,
treated with NaClO4 at 2000 PPM was greater than that
treated with the two lower concentrations (p < .005), but
none were different than control. The pH group mean for
manure treated with NaClO4 at day 21 was less than control
pH (p < .025), and pH for the 2000 PPM NaClO4 was higher

than that for the two lower treatment concentrations

(p < .05). Neither H202 nor KMnO4 influenced pH.

Ammonia
Concentration of ammonia (NH3) in the air over

manure as affected by treatment and time is presented in

79

TABLE 19
le at Three Intervals After Addition of
Three Chemicals to Fresh Liquid
Dairy Manure
(Experiment Ib)

 

 

 

. Day
Chemicals and Levels 42 7 21
Sodium Perchlorate (PPM)
250 6.35 6.35 6.10
500 6.40 6.45b 6.10c
2000 6.55 6.75 6.30
ZZZ@@IZZIZZIZIIIIEPiiiifiiiiiyi
Hydrogen Peroxide (PPM)
75 6.40 6.45 6.30
150 6.50 6.50 6.20
300 6.50 6.55 6.20
ZZZ@§IIZIIIIZIIIZEPIIZEFZZZEP:
Potassium Permanganate (PPM)
250 6.55 6.55 6.30
500 6.60 6.55 6.25
1000 6.60 6.50 6.25
::I@@II:I:Z:IZ:IIE¥IIZE¥IIIE?Z
Control 6.65 6.55 6.40
SEM2 .08 .06 .05

 

1Each value an average of two jars.

2SEM = standard error of each mean of two jars on a
given day.

aSignificantly different (p < .025) than control
within the same column.

bSignificantly different (p < .005) than means from
lower treatment concentrations within the same treatment
group within the same column.

(:1? < .05.

80

Table 20. Group mean ammonia concentration for parafor-
maldehyde at day two was lower than control (p < .05).
Due to the large variation from jar to jar, as indicated
by the large standard errors, no other statistically
significant differences in ammonia concentrations were
found, but Values for paraformaldehyde treatments at all
times were less than for control, acrolein or H3PO4
treatments.

Concentration of ammonia in the air over manure
after addition of NaClO4, H202 or KMnO4 is presented in
Table 21. Ammonia concentration at day seven for the high
level NaClO4 was higher than for the two lower concen-
trations (p < .005), but none were different than control.
No other differences were detected. H202 and KMnO4
exerted no apparent changes on ammonia in air over the
manure.

When comparing data from Table 20 and Table 21
there was no consistent time trend for ammonia release
from fresh manure. Values in Table 20 decrease with time
while those in Table 21 increase. Manure used in these
two parts of the experiment was collected at different

times, and may have been different in some respects,

although conditions were kept fairly much the same.

Odor Panel Evaluation

 

Table 22 shows the relationship of addition of

paraformaldehyde, acrolein and H3PO4 to offensiveness

81

TABLE 20

Ammonia1 in the Air Space over Fresh Liquid

Dairy Manure as Affected by Treatment
and Time (Experiment Ia)

 

 

 

 

. Day
Chemicals and Levels 2 7 14 21
Paraformaldehyde (PPM)

7,000 217 203 140 58
10,000 133 126 135 107
30,000 156 222 207 183

ZIZIEeEnIIZZZZIZZZIE9EZIIBIIZZIEIIZIIIE
Acrolein (PPM)
l 191 227 174 209
100 347 229 252 246
IZZEeEnZIZIIIIZ2225922222522221322228
Phosphoric Acid (PPM)
657 282 228 217 277

1,000 212 278 195 309
10,000 239 185 204 265

2225653222:22222229222252:2295:2228!
Control 366 271 269 202
53142 50 33 55 42

1

Each value an average of two jars express
micrograms of ammonia per liter of air.

2SEM = standard error of each mean of two

given day.

aSignificantly different (p < .05) than co
within the same column.

ed as

jars on a

ntrol

82

TABLE 21

Ammonial in the Air Space over Fresh Liquid
Dairy Manure as Affected by Treatment
and Time (Experiment Ib)

 

 

 

 

. Day,
Chemicals and Levels 2 7 21
Sodium Perchlorate (PPM)
250 169 238 388
500 187 224 402
2000 256 473a 346
I:2&5222ZZZZZZZZZIEIZZIPZZZZE2
Hydrogen Peroxide (PPM)
75 ' . 193 240 381
150 220 203 434
300 155 177 387
ZZI®@ZIZIIIZZIZI:IPEIZIFZZZZFI
Potassium Permanganate (PPM)
250 222 256 435
500 238 265 453
1000 223 257 413
IZZ®@ZZZII:ZI:::ZZPEIII§EZZIBE
Control 246 282 505
SEM2 31 35 51
1

Each value an average of two jars expressed as
micrograms of ammonia per liter of air.

2SEM = standard error of each mean of two jars on a

given day.

aSignificantly different (p < .005) than means from
lower treatment concentrations within the same treatment
group within the same column.

83

TABLE 22

Offensiveness and Strength Ratings1 Four and
Five Days After Addition of Three
Chemicals to Fresh Liquid
Dairy Manure
(Experiment Ia)

 

 

Offensiveness2 Strength3
Paraformaldehyde (PPM)

7,000 3.9 4.6
10,000 3.3 3.5
30,000 4.5 4.9

Acrolein (PPM)
l 6.4 6.4
100 6.0 6.8
Phosphoric Acid (PPM)
657 5.9 5.8

1,000 5.0 4.7

10,000 5.0 5.7
Control 5.7 5.2

 

1Each value an average of two jars evaluated by
five odor panelists each.

20 = not offensive, 2 = very faint offensiveness,
4 = faint offensiveness, 6 = definite offensiveness, 8 =
strong offensiveness, 10 = very strong offensiveness.

30 = no odor, 2 = very faint odor, 4 = faint odor,

6 = definite odor, 8 = strong odor, 10 = very strong odor.

84

(quality) and strength (quantity) of fresh dairy manure at
four and five days. Paraformaldehyde at 7000, 10,000 and
30,000 PPM decreased offensiveness ratings to 3.9, 3.3 and
3.5 respectively compared to control of 5.7. Strength
ratings were 4.6, 3.5 and 4.9 respectively compared to
control of 5.2. The lower the number the less the offensive-
ness or strength of the odor. Acrolein or H3PO4 did not
reduce offensiveness or strength ratings.

Comparative ratings when NaClO4, H202 and KMnO4
were added and evaluated at four and five days, are in

H O and KMnO at 250 and 500 PPM did

4' 2 2 4
not reduce offensiveness or strength ratings. KMnO4 at

Table 23. NaClO

1000 PPM had an offensiveness rating of 4.4 and strength
rating of 4.3 compared to control values of 6.5 and 6.1
respectively.

The correlation coefficients between offensiveness
and strength for values in Table 22 (n = 90) and Table 23
(n = 100) were +.66 and +.7l respectively, thus estab-
lishing a fairly close relationship between odor quality
and quantity. Therefore a strong odor would usually be

considered an offensive odor.

Experiment II

 

Manure in this experiment was obtained from the
liquid manure pit at the Michigan State University dairy
farm which was from the milking parlor and equipment area,

and will be termed decomposed manure. This manure averaged

85

TABLE 23

Offensiveness and Strength Ratings1 Four
and Five Days After Addition of Three
Chemicals to Fresh Liquid Dairy
Manure (Experiment Ib)

 

 

Offensiveness2 Strength3
Sodium Perchlorate (PPM)
250 5.3 5.6
500 5.4 5.4
2000 5.6 5.4
Hydrogen Peroxide (PPM)
75 6.4 6.7
150 6.0 5.7
300 6.2 6.0
Potassium Permanganate (PPM)
250 6.3 5.8
500 5.9 5.6
1000 4.4 4.3
Control 6.5 6.1

 

1Each value an average of two jars evaluated by
five odor panelists each.

20 = not offensive, 2 = very faint offensiveness,

4 = faint offensiveness, 6 = definite offensiveness, 8 =
strong offensiveness, 10 = very strong offensiveness.

3O = no odor, 2 = very faint odor, 4 = faint odor,
6 = definite odor, 8 = strong odor, 10 = very strong odor.

86

about one percent dry matter indicating a large amount of
wash water and little feces. This type of manure (decom-
posed) was evaluated to see if there were differences when

compared to fresh manure.

pg

The pH's of this decomposed liquid dairy manure
before and after addition of lime, paraformaldehyde, H202
and KMnO4 are in Table 24. Lime increased mean pH to
about 12 compared to control values of 7.1 to 7.3 (p <
.005). At days one, four and seven, addition of 10,000
PPM elicited a larger pH than 5000 PPM (12.35 to 12.55 >
11.6 to 12.1, p < .005).

Paraformaldehyde at day one did not change pH
from that of control, but at day four and seven pH was
lower than that of control (p < .005). The pH at day four
and seven for 10,000 PPM paraformaldehyde was less than
that for the two lower concentrations (p < .025) indicating
pH decreased with increasing paraformaldehyde concen-
trations.

H202 did not alter pH from that of control. KMnO4
at day one, four and seven increased pH above that of
control (p < .005). The pH at day four and seven for 1000

PPM KMnO was greater than that for 500 PPM (p < .05 and

4
.025 respectively), thus demonstrating pH increase with

increasing KMnO4 concentration.

87

TABLE 24

le Before and After Addition of Four
Chemicals to Decomposed Liquid
Dairy Manure (Experiment II)

 

Day

 

 

Chemicals and Levels _1 1 4 7
Lime (PPM)
5,000 6.85 11.60b 12.10b 11.75b
10,000 6.80 12.35 12.55 12.55
I I I @6511: Z Z I I I I I Z I 26:82 I 1129?: 1223?: 12:1?
Paraformaldehyde (PPM)
1,000 6.85 7.00 6.90 6.70d
5,000 7.00 7.20 6.70 6.40
10,000 6.90 7.00 6.50c 6.25C
:I:®§ZIZIZZIZZZEEZZDEIZBDT_33§
Hydrogen Peroxide (PPM)
100 6.90 7.05 7.25 7.20
500 6.80 7.00 7.10 7.10
I::@@IZIIZIZZZIFEEIYDEIYDEZPQE
Potassium Permanganate (PPM)
500 6.95 7.50 7.65d 7.55c
1,000 7.20 7.60 7.95 7.90
I:Z@§ZZZZIIZIIIPEEZPEEIPBTZEP?
Control 6.95 7.15 7.30 7.30
SEM2 .07 .06 .06 .06

 

1Each value an average of two jars.

2SEM = standard error of each mean of two jars on a
given day.

aSignificantly different (p < .005) than control
within the same column.

bSignificantly different (p < .005) than means from
lower treatment concentrations within the same treatment
group within the same column.

Cp < .025.

dp < .05.

88

Ammonia and Ammonium Ion

 

Data in Table 25 represents a preliminary trial
testing the relationship between total ammonia in liquid
manure to treatment. No statistical analysis was done
because values represent only one jar per treatment level.
No definitive conclusions could be made, but these data
suggest some treatments reduced total ammonia. Therefore,

this was pursued further in Experiment III.

Nitrate

Each treatment level was checked for presence of
nitrates, but none were detected. Since this manure was
low in dry matter (1 percent) and relatively clear the

color reaction could have been detected.

Odor Panel Evaluation

 

Efficacy of lime, paraformaldehyde, H20 and KMnO

2 4
on changing odor offensiveness of decomposed liquid manure
is present in Table 26. Lime did not reduce odor offen-
siveness much below five (faint to definite offensiveness)
at the days evaluated. Paraformaldehyde at 5000 PPM
reduced offensive rating at day one to 3.8 (faintly
offensive), and at day three all concentrations may have
caused a slight reduction. At day eight only the 1000
PPM paraformaldehyde reduced offensiveness (3.5).

At day one 500 PPM H O and 500 and 1000 PPM KMnO

2 2 4
reduced offensiveness ratings to 3.0, 3.0 and 3.8

Total Ammonial

89

TABLE 25

Dairy Manure (Experiment II)

in Manure After Addition of
Four Chemicals to Decomposed Liquid

 

 

 

 

Chemicals and Levels Day
2 10
Lime (PPM)
5,000 203 192
10,000 199 164
Paraformaldehyde (PPM)
1,000 255 218
5,000 6 213 129
10,000 210 85
Hydrogen Peroxide (PPM)
100 253 228
500 245 190
Potassium Permanganate (PPM)
500 246 185
1,000 249 168
Control 246 231
1

liter of manure.

Each value an average of duplicate samples taken
from the same jar expressed as milligrams of ammonia per

90

TABLE 26

Offensiveness Ratings1 at Three Intervals
After Addition of Four Chemicals to
Decomposed Liquid Dairy Manure
(Experiment II)

 

 

 

Chemicals and Levels Dal
l 3 8
Lime (PPM)
5,000 5.8 7.3 6.5
10,000 6.5 6.7 4.8
Paraformaldehyde (PPM)
‘1,000 5.3 5.0 3.5
5,000 3.8 5.0 6.0
10,000 4.5 5.0 7.5
Hydrogen Peroxide (PPM)
100 5.5 7.0 5.0
500 3.0 6.8 7.3
Potassium Permanganate (PPM)
500 3.0 5.7 5.8
1,000 3.8 4.8 5.8
Control 7.7 6.3 6.8

 

1Each value an average of two jars evaluated by
three odor panelists each using the scale: 0 = not offensive,
2 = very faint offensiveness, 4 = faint offensiveness,
6 = definite offensiveness, 8 = strong offensiveness,
10 = very strong offensiveness.

91

respectively compared to control values of 7.7. This
reduction was to the "faintly offensive" range. By day

three values were similar to control.

Experiment III

 

Fresh feces and urine was added to manure taken
from the liquid manure pit at the Michigan State University
dairy farm producing a product containing about 5.6 per-
cent dry matter. This remained at ambient temperature for
a month to allow partial decomposition before being used
in this experiment, and will be referred to as decomposed
manure. This manure was considered to be more like that
found under field conditions since a larger amount of

solids was in the manure than in Experiment 11.

Microbial Counts

 

Aerobic microbial numbers after addition of lime,
paraformaldehyde, H202 and KMnO4 to partially decomposed
liquid dairy manure is presented in Table 27. At day one
all values were similar to control. However, by day
eight paraformaldehyde reduced aerobic counts, and extent
of reduction was greater as paraformaldehyde concentration
increased. Lime, H202 and KMnO4 additions did not reduce
number of microorganisms, and possibly lime and KMnO4

increased numbers.

92

TABLE 27

Aerobic Microbial Numbers1 at One and Eight
Days After Addition of Four Chemicals
to Decomposed Liquid Dairy Manure
(Experiment III)

 

 

 

Chemicals and Levels 1 Day 8

Lime (PPM) 5 5
5,000 89x105 330x105
10,000 140x10 530x10
Paraformaldehyde (PPM) 5 5
1,000 110x105 40x105
5,000 100x105 5.1x105
10,000 86x10 0.4x10
Hydrogen Peroxide (PPM) 5 5
100 98x105 180x105

500 75x10 250x10
Potassium Permanganate (PPM) 5 5
500 84x105 320x105

1,000 86x10 420x10
Control 74x105 180x105

 

1Each value an average of duplicates taken from the
same jar expressed as microorganisms per gram of treated
manure.

93

ELI

Some alteration in pH was noted when these chemi-
cals were added to this type of manure (Table 28). Mean
pH for lime addition was greater than for control (p <
.005). Lime at 10,000 PPM increased pH above that of 500
PPM (p < .005) at day one, four and nine. Mean pH for
paraformaldehyde addition was not significantly less than
control until day nine (p < .005). At this time pH of the
10,000 PPM paraformaldehyde treatment was less than the
lower two concentrations (p < .005), and the 5000 PPM was
less than the lowest concentration (p < .025).

H202 did not change pH. KMnO4 increased pH above
control at day four (p < .05) and nine (p < .025). At
1000 PPM KMnO4 pH tended to be higher than 500 PPM, but

only at day nine was it significant (p < .005).

Ammonia and Ammonium Ion

 

Changes in total ammonia (NH3 and NH4+) in liquid
manure as influenced by treatment are shown in Table 29.
Concentration of total ammonia after lime addition was
higher than that of control (p < .05) only on day four.
Paraformaldehyde reduced total ammonia at day 11 (p <
.005), and the 10,000 PPM treatment was lower than the two
lower ones (p < .005). Values indicate an inverse rela-
tionship of total ammonia to concentration of paraformalde-
hyde added. H202 and KMnO4 did not change values relative

to control.

94

TABLE 28

le Before and After Addition of Four
Chemicals to Decomposed Liquid Dairy
Manure (Experiment III)

 

 

 

 

. Dex.
Chemicals and Levels _1 1 4 9
Lime (PPM)
5,000 5.67 7.27d 7.77d 8.20d
10,000 5.67 8.57 8.67 8.90
I:Z@@IZZIZZZ:I::331:L?333?ZE¥3
Paraformaldehyde (PPM)
1,000 5.60 5.57 5.97 5.87
5,000 5.70 5.57 5.87 5.63:
10,000 5.70 5.60 5.73 5.43
ZII®@ZZ22222222233123323352391
Hydrogen Peroxide (PPM)
100 5.70 5.57 6.07 6.07
500 5.67 5.60 5.93 6.20
I:Z@@IZIIZZIZZZIEFEIE$233§IEPI
Potassium Permanganate (PPM)
500 5.67 5.73 6.17 6.33d
1,000 5.70 5.87 6.43 6.60
ZII@@IIZZ:Z:::I:33§IE@:33TIEPE
Control 5.67 5.60 5.93 6.27
SEM2 .03 .08 .10 .05
1

Each value an average of three jars.

2SEM = standard error of each mean of three jars
on a given day.

aSignificantly different (p < .005) than control
within the same column.

bp < .025. cp < .05.

dSignificantly different (p < .005) than means
from lower treatment concentrations within the same treat-
ment group within the same column.

6p < .025.

TABLE 2 9

95

Total Ammonia1 in Manure Before and After
Addition of Four Chemicals to
Decomposed Liquid Dairy
Manure (Experiment III)

 

 

 

. Day
Chemicals and Levels _2 4 11
Lime (PPM)
5,000 323 411 418
10,000 329 389 390
ZIZEeEnII22222222223262:224?.03222424:
Paraformaldehyde (PPM)
1,000 347 347 356
5,000 329 334 281
10,000 332 299 152C
II:EeEnII:22222222223362222327222:233:
Hydrogen Peroxide (PPM)
100 342 358 386
500 331 348 390
IZIEeEn:ZZZ:I:22222232722223332222338:
Potassium Permanganate (PPM)
500 361 394 394
1,000 340 380 391
ZIZIEeEnIIZZIIII:ZIZI3EIIIZI3E7ZZII3§3Z
Control 332 352 401
SEMZ 7 13 20
l

 

Each value an average of three jars done in dup-

licate expressed as milligrams of ammonia per liter of

manure.
2
on a given day.

SEM = standard error of each mean of three jars

aSignificantly different (p < .005) than control

within the same column.

bp < .05.

CSignificantly different (p < .005) than means
from lower treatment concentrations within the same treat-

ment group within the same column.

96

When the change of the ammonia concentration with
time for the paraformaldehyde treatment was compared to
the change with time in the control, they were different

(p < .005).

Odor Panel Evaluation

 

Offensiveness ratings after treatment addition is
present in Table 30. At day two 5000 PPM lime reduced
offensiveness rating (3.7 vs. 5.5). Paraformaldehyde and
H202 did not reduce odor offensiveness at the times evalu—
ated. KMnO4 tended to reduce odor offensiveness below
that of control at all three days, although not below the

"faintly offensive" rating.

Experiment IV

 

Manure used in this experiment was prepared by
addition of fresh fecal matter and urine to liquid manure
taken from the pit at the Michigan State University dairy
farm. This material remained at room temperature for about
a month before use in this experiment, and will be referred
to as decomposed manure. Dry matter content was about 4.7
percent. This experiment was undertaken because results
from odor evaluation in the first three experiments were

hard to interpret.

Odor Panel Evaluation

 

Rankings of offensiveness for two concentrations

of paraformaldehyde or control manures at three time

97

TABLE 30

Offensiveness Ratings1 at Three Intervals
After Addition of Four Chemicals to
Stored Liquid Dairy Manure
(Experiment III)

 

 

 

 

. Day
Chemicals and Levels 1 2 8
Lime (PPM)
5,000 5.1 3.7 6.7
10,000 5.9 6.0 7.4
Paraformaldehyde (PPM)
1,000 5.9 5.7 5.1
5,000 5.7 5.2 5.0
10,000 6.0 5.1 5.3
Hydrogen Peroxide (PPM)
100 5.9 5.7 6.3
500 5.5 5.9 6.8
Potassium Permanganate (PPM)
500 ' 5.9 4.3 6.5
1,000 4.6 4.3 5.0
Control 5.3 5.5 6.9
1

Each value an average of two jars evaluated by
five odor panelists using the scale: 0 = not offensive,
2 = very faint offensiveness, 4 = faint offensiveness,
6 = definite offensiveness, 8 = strong offensiveness,
10 = very strong offensiveness.

98

intervals are in Table 31. No significant differences in
rankings could be detected between the two treatment con-
centrations or between the treatments and control. There-
fore, paraformaldehyde did not reduce odor offensiveness
when added to this type of manure.

H202 at 100 and 500 PPM was ranked in reference to
control (Table 32). At nine and 15 hours after addition of
500 PPM H202 the odor was judged to be less offensive than
that for 100 PPM (p = .01) or control (p = .05). At 36 to
40 hours and eight days, no differences were detected.

Odor rankings of manure with 500 and 1000 PPM KMnO4
added and control are in Table 33. At all three time
periods there was no significant ranking difference between
500 and 1000 PPM KMnO . Manure treated with 500 PPM KMnO

4
reduced offensiveness when compared to control (p = .01)

4

at all time periods. Manure treated with KMnO4 at 1000 PPM
was judged to be less offensive than control at nine to 15
hours (p = .05), 36 to 40 hours (p = .01) and eight days
(P = .02).

Table 34 presents rankings for 5000 PPM parafor—
maldehyde, 500 PPM KMnO4 and control manures. At nine
to 15 hours no difference in odor offensiveness was
detected between KMnO4 and control, but paraformaldehyde
was more offensive (p = .01). By 36 to 40 hours no ranking

differences between paraformaldehyde and control was

detected, but KMnO4 was less offensive than paraformaldehyde

99

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103

(p = .01). Also odor ranking for KMnO4 treated manure did

not differ from that of control. At day eight KMnO was

4
less offensive than paraformaldehyde (p = .01) and control
(p = .02) indicating a long-term odor reduction due to
KMnO4 addition.
Odor rankings of manure with 5000 PPM paraformalde—
hyde, 500 PPM H202 and control show some differences
(Table 35). H202 treatment and control were not different
at nine to 15 hours, but paraformaldehyde was more offensive
than H202 (p = .01) and control (p = .02). At 36 to 40
hours no difference in odor offensiveness between the two
treatments and control could be detected, but paraformalde-
hyde was more offensive than H202 (p = .02). No differ-
ences in odor offensiveness were detected at day eight.
Table 36 presents odor comparisons of 500 PPM
KMnO4, 500 PPM H202 and control manures. At nine to 15
hours no differences were detected, but by 36 to 40 hours,

control was more offensive than KMnO (p = .01) or H O

4 2

(p = .05) treated manures. No difference was detected

2

between the two treated manures. KMnO4 treated manure
was less offensive than H202 (p = .05) or control manures
(p = .02) at day eight, with no difference between control

and H202 treated manure.

Rankings of offensiveness of 100 and 500 PPM H202
and control manures are in Table 37. Both 100 and 500 PPM

H202 treatments reduced offensiveness when compared to

104

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106

TABLE 37

Odor Panel Rankingsl at Four Time Periods Comparing Two
Concentrations of H O and Control (Experiment IV)

 

 

 

 

 

 

 

2 2
1/2-1 1/2 Hours 6-8 Hours
PaneliSt H202 a H202 a Controlb H202 ca H202 Controld
100 PPM 500 PPM 100 PPM 500 PPM
A 2 1 3 3 1 2
B 2 1 3 2 1 3
c 2 1 3 1 2 3
D 2 1 3 2 1 3
E 1 2 3 3 1 2
F 1 2 3 3 1 2
30-32 Hours 9 Days
PaneliSt H202 H202 Controle H202 H202 Controlf
100 PPMe 500 PPMe 100 PPM 500 PPM
A 3 1 2 2 3 1
B 1 3 2 3 1 2
c 3 2 1 3 1 2
n 2 1 3 2 1 3
E 2 1 3 1 2 3
F 1 3 2 2 1 3
G 1 3 2 2 1 3
H — - - 3 1 2

 

1Each value a rating given by each panelist using the scale:
1 = least offensive, 2 = moderately offensive, 3 = most offensive.

a b c d e f . . . . .
' ' ' ’ ' Treatments hav1ng different superscripts within

each time period differ significantly (P.f.'05)°

107

control manure (p = .05) at 0.5 to 1.5 hours, and there was
no difference in offensiveness between concentrations of
H202. At six to eight hours the 500 PPM H202 treated
manure was less offensive than control (p = .05), with no
difference in offensiveness between 100 PPM H202 treated
manure and the other two (500 PPM H202 and control). After
this time no differences were detected.

Odor rankings of manure with addition of 500 PPM
H202, 500 PPM KMnO4 and control show consistent differ-
ences (Table 38). At 0.5 to 1.5 hours H202 treated manure
was less offensive than KMnO4 or control manures (p = .05).
At six to eight hours both H202 and KMnO4 treated manure
was less offensive than control (p = .05), but H202
treated manure was less offensive than KMnO4 (p = .05) and
control manures (p = .02) at 30 to 32 hours. By nine days

KMnO4 treated manure was less offensive than H202 (p = .01)

and control manures (p = .02).

Experiment V

 

Manure used in this experiment was the same as
that in Experiment IV, except manure was allowed to remain
at room temperature for about three months before use, and
will be referred to as decomposed manure. Dry matter con-
tent was about five percent. This experiment was under-
taken to compare some of the commercial products now on the

market.

108

TABLE 38

Odor Panel Rankings1 at Four Time Periods Comparing
H202 to KMnO and Control (Experiment IV)

 

 

 

 

 

 

 

4
7 1/2-1 1/2 Hours 6-8 Hours
Panelist H202 KMnO4 Controlb H202 KMnO4 Controld
500 PPMa 500 PPMb 500 PPMC 500 PPMC
A l 2 3 2 1 3
B l 2 3 2 l 3
C l 3 2 2 1 3
D l 3 2 2 l 3
E l 3 2 l 2 3
F 1 2 3 l 2 3
30-32 Hours 9 Days
Panelist H202 e KMnO4 f Controlf H202 g KMnO4 h Control9
500 PPM 500 PPM 500 PPM 500 PPM
A l 2 3 2 l 3
B l 3 2 2 1 3
C 1 3 2 3 1 2
D 1 3 2 2 l 3
E l 3 2 2 l 3
F 2 l 3 2 1 3
G 1 3 2 3 2 l
H - - - 2 1 3

 

1Each value a rating given by each panelist using the scale:
1 = least offensive, 2 = moderately offensive, 3 = most offensive.

a C d f h - - '
'b' ' ,e, ,g, Treatments hav1ng different superscripts

within each time period differ significantly (p_: .05).

36

di

dz;

Z}

fI

CI

I(.(II| ‘

109

Odor Panel Evaluation

 

Rankings of offensiveness of 1430 PPM Odor Mask,
360 PPM Pit-Zyme and control manures are in Table 39. No
differences in offensiveness could be detected until eight
days. At this time Odor Mask treated manure was more
offensive than Pit-Zyme or control manure (p = .05).

Table 40 presents odor comparisons of 360 PPM Pit-
Zyme, 360 PPM Sep-Zyme "O" and control manures. No dif-
ferences in odor offensiveness could be detected until day
eight. Pit-Zyme treated manure was less offensive than
control manure (p = .05), but not different than Sep-
Zyme "O".

Odor rankings of 1430 PPM Odor Mask, 360 PPM Sep-
Zyme "O" and control manures showed no consistent differ-

ences (Table 41) at the times evaluated.

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112

 

 

 

 

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V. DISCUSSION

Results of these experiments indicate certain of
the treatments evaluated were effective in changing odor
produced from fresh as well as decomposed dairy waste.

Most of these changes could be attributed to either anti-
microbial or oxidative properties of the additive that pre-
vented formation of malodors or destroyed malodors already
produced.

Table 42 was included in an attempt to demonstrate
the diversity of the manure used in these experiments.
Manure varied in dry matter content and length of storage

before treatment.

Influence on Microbial Numbers by Additives

Experiment I was undertaken to evaluate treat-
ments on the prevention of odorous compound formation in
fresh dairy manure. Paraformaldehyde at 7000 and 30,000
PPM depressed total aerobic and anaerobic microbial numbers
for at least 22 days (Table 16). The amount of reduction
increased with time and paraformaldehyde concentration, with
numbers being lowest for 30,000 PPM at day 22. At this
time aerobic and anaerobic counts for 30,000 PPM parafor-
maldehyde were 0.16 x 104 and 0.16 x 104 respectively

113

114

TABLE 42

Characteristics of Manure Used in
Experiments I through V

 

Length of Storage

 

. Type of
Experiment Dry Matter (%) Befoigdgiegfiment Manure
I 13.0 0 fresh
II 1.0 < 1 month decomposed
III 5.6 1 month decomposed
IV 4.7 < 1 month decomposed
V 5.0 < 3 months decomposed

 

Experiment I treatments: paraformaldehyde, acrolein,

H3PO4, NaClO4, H202 and KMnO4.

Experiments II and III treatments: lime, parafor-
maldehyde, H202 and KMnO4.
Experiment IV treatments: paraformaldehyde, H202
and KMnO4.

Experiment V treatments: Pit-Zyme, Sep-Zyme "O"
and Odor Mask.

115

compared with control (35 x 107 and 9.7 x 107 respectively).
This was a reduction of over 99 percent for both aerobic
and anaerobic counts. This antimicrobial action of para-
formaldehyde was also observed by Seltzer et a1. (1969)

and Veloso et a1. (1974). Formaldehyde is the active
bactericidal agent, and is formed by the depolymerization
of paraformaldehyde. This reaction occurs slowly under
most conditions, allowing for prolonged bactericidal action.

Paraformaldehyde addition to decomposed manure at
1000, 5000 and 10,000 PPM did not reduce aerobic counts at
day one, but at eight days counts were reduced to below
25 percent of control (Table 27). At day eight 10,000
PPM paraformaldehyde reduced aerobic counts to 0.5 x 105
compared with control (180 x 105). This was a 99 percent
reduction in numbers.

Acrolein was bactericidal at all concentrations
added. H3PO4 at the highest concentration produced a
slight reduction in aerobic and anaerobic counts until
after day 15 in fresh manure, but by day 22 values were
similar to control (Table 16).

NaClO4 at the highest concentration produced a
reduction in aerobic and anaerobic counts until day eight
in fresh manure, but by day 15 values were similar to
control (Table 17).

Bactericidal action of acrolein, H PO

3 4

at the concentrations added was probably not sufficient

and NaClO4

116

to prevent formation of odorous compounds in fresh
manure.

Lime in decomposed manure, and H202 and KMnO4
in fresh and decomposed manure produced no change in
microbial counts. The oxidants, H202 and KMnO4, would
tend to produce conditions favorable to aerobes, but at
concentrations used, this was not detected in these
microbial counts. Ritter et al. (1975) found dissolved
oxygen to increase in manure proportionally to the amount
of H202 added, and thus would expect more aerobes to be
present. It may have been our assay for aerobes and
anaerobes was not precise enough to note differences.

Selective bactericidal action may have occurred
with some treatments. For example lime raised pH to above
10 which is above the optimum for most bacteria (Miner,
1971), and only the least fastidious bacteria would be
expected to survive and grow at this pH. H202 may
selectively act as a bactericide to sulfate reducing
bacteria that are responsible for formation of hydrogen
sulfide (FMC Corporation). Therefore, even though total
numbers of bacteria may not be reduced certain species may
not grow or survive. Such a shift in microbial population
could change odor characteristics.

Aerobic microbes were more numerous in fresh than

in decomposed waste. This could be due to more sub-

strate (dry matter) in the fresh manure indicating a

117

greater rate of decomposition, and therefore more
microbes.

Many of the aerobic microbes were probably facul-
tative anaerobes meaning they would also be present under
anaerobic conditions. Thus the total number of micro-
organisms in Experiment I was probably not the sum of
aerobic and anaerobic counts since there would tend to be

some overlap between the two.

Influence on pH by Additives

 

Paraformaldehyde decreased pH in fresh and decom-
posed manure which agrees with observations made by Veloso
et al. (1974). This pH decrease probably results from
decreased ammonia concentrations in the manure. Fluctu-
ations of pH with time were reduced indicating a decreased
rate of decomposition and decreased production of odorous
compounds. This reduced decomposition was a direct result
of the decreased number of microorganisms present in the
manure.

The pH was reduced as concentration of H3PO4 in
fresh manure increased (Table 18). An explanation for the
reduced microbial numbers in H3PO4 treated manures for one

and eight days caused by a simultaneous decrease in pH is

not readily evident since at day 21 H PO4 reduced pH, but

3
microbial numbers were as great or greater than control.
KMnO4 tended to have no effect on pH of fresh

manure, but tended to increase it in decomposed manure.

118

This pH increase is a result of MnO4 reacting with hydro-
gen ions to produce water. The difference between fresh
and decomposed manure can be explained by the fact that
dry matter in fresh manure was 13 percent compared to 5.6
percent or below in decomposed manure. Thus concentration
of added KMnO4 per unit of dry matter was less for fresh
manure. Also fresh manure would tend to counteract the
expected pH increase from KMnO4 by production of organic
acids during anaerobic decomposition.

Lime increased pH values in decomposed manure at
all concentrations used. This pH increasing property of
lime was used by Hammond et a1. (1966), Day (1966) and Cole
et a1. (1974) to reduce offensiveness of liquid swine
manure. Lime probably does not decrease production of
odorous compounds, but does change composition of gases
volatilized. For example with pH 10 or above, very little
hydrogen sulfide or organic acids would be volatized while
ammonia and amine volatilization would increase (Miner,
1974).

Acrolein added to fresh manure or H202 to fresh
and decomposed manure did not alter pH values from control.

In fresh manure pH tended to decrease with time
while in decomposed manure it increased. This relationship
was statistically significant when controls in Table 18 and
19 were compared to controls in Table 24 and 28. Fresh

manure would be undergoing fermentation and produce organic

119

acids, thus decreasing pH. Decomposed manure would probably
have completed fermentation of readily available carbohydrate
and pH would be increasing due to ammonia production from
protein degradation. Also microbes in decomposed manure

may be converting organic acids to methane resulting in a

pH increase.

Influence on Ammonia and Ammonium Ion
bypAdditives

 

 

The pH of most treated or control manure was near
or below neutral (pH 7) indicating most of the ammonia was
in the NH4+ nonvolatile form. Ammonia (NH3) concentrations
in the air space over all manures in Experiment I were such
that volatilization of ammonia had to occur, but would not
have been expected at the observed pH values. More careful
observation revealed the top layer of manure became basic
(pH > 8) allowing release of ammonia (NH3) while the center
and bottom remained neutral or acidic. Therefore, there
was stratification during storage of this manure. This is
probably similar to what occurs in large storage tanks
where NH3 can escape from the upper portion while the lower
portion remains acidic.

Ammonia concentrations in the air space over manure
were measured with the idea that ammonia concentration would

be related to other odorous gases. Miner and Stroh (1975)

considered ammonia to be volatilized in quantities

120

sufficiently related to the more odorous compounds so that
ammonia could be used as an odor indicator.

Ammonia concentration in the manure air space was
significantly reduced by paraformaldehyde at day two and
this trend continued for 21 days although this trend was
not statistically significant because of excessive vari-
ation from jar to jar (Table 20). This reduction of
ammonia was probably a result of bactericidal properties
of formaldehyde reducing breakdown of urea and proteins.
Also the nonvolatile compound hexamethylene tetramine could
have been produced by reaction of formaldehyde and ammonia
(Seltzer et al., 1969).

NaClO4 caused no change in air space ammonia con-
centrations except at day seven when ammonia concentra-
tion was positively related to amounts of NaClO4 added.

The pH of the 2000 PPM NaClO treatment was slightly

4
elevated, but insufficiently high to account for the
ammonia in the air since small fluctuations in pH did not
result in concurrent changes in gaseous ammonia concentra—
tions.

No differences in ammonia concentrations were
PO H O or KMnO

detected over acrolein, H 4, 2 2 4 treated

3
manures. Miner and Stroh (1975) found no difference in
ammonia desorption in KMnO4 treated manure.

Ammonia in the air space over all manures in

Experiment I had extremely large variation from jar to jar

121

so that no definite conclusions can be made from these
results. Also treatments could change pH and thus ammonia
in the air over treated manure without decreasing offen-
siveness. These results indicate that ammonia by itself is
a fairly poor measurement of changes in odor offensiveness.

Ammonia volatilization represents a loss of
nitrogen from manure. Miner (1974) used data from
Hashimoto and Ludington (1971) and calculated that at a pH
of 8.0 and a temperature of 20° the nitrogen content of
liquid poultry manure would be lowered 3.3 percent per day
by ammonia volatilization. A pH of 9.0 would decrease
nitrogen at a rate of 23 percent per day. This system was
agitated keeping dissolved ammonia in contact with the air.
In a nonagitated system as used in this study a slower rate
of desorption would be expected. Also, stratification
would occur with much of the lighter material forming a
crust producing a barrier between dissolved ammonia and
air.

In Experiments II and III total ammonia present in
manure as NH4+ and NH3 was measured to determine treatment
effects on formation and liberation. Only at the high pH
observed in lime treated manure would the major portion of
ammonia be in the NH3 form.

In Experiment II total ammonia (NH4+ and NH3)
concentrations decreased with time but in Experiment III

they increased. This might be explained on the basis

122

of differences in dry matter content and extent of decom-
position during manure storage before tests were initiated.
Manure in Experiment 11 had about one percent dry matter
while Experiment III averaged 5.6 percent. Also manure

in Experiment II had been decomposing for several weeks
and decomposition was nearly complete, while that in
Experiment III had decomposed for about four weeks before

the tests were conducted. Thus more ammonia (NH + and NH3)

4
formation would be expected in Experiment III resulting in

a net increase in ammonia while Experiment II would decrease
due to volatilization and decreased breakdown of proteins.
Ammonia as used here would be an indication of anaerobic
decomposition (protein degradation).

Total ammonia found in the manure in Experiment III
was almost twice the amount in Experiment II, and was
approximately related to the amount of substrate present.

Addition of paraformaldehyde slightly decreased
total ammonia in decomposed manure at day four, and sig-
nificantly reduced it at day 11 (Table 29). This reduction
was not likely due to atmospheric loss since decreased
desorption of ammonia from paraformaldehyde treated manure
was found in Experiment I. Ammonia may have been oxidized

to nitrate (NO -) with agitation of manure, but this was

3
discounted when no nitrates were found. Therefore, the
decreased ammonia concentration must have resulted from

reduced degradation caused by the bactericidal action of

123

formaldehyde and/or the binding of formaldehyde to ammonia.
The result would be increased nitrogen retention as was
observed by Seltzer et a1. (1969).

Lime acted to increase total ammonia present in the
treated manure at day four, but at day 11 no difference from
control could be noted (Table 29). This increase in ammonia
may have resulted from a temporary increase in protein

degradation during the first days after addition of lime,

but this relationship is uncertain.

Influence ongdor Panel Evaluation
byiTreatments

 

 

Odor offensiveness of fresh manure treated with
paraformaldehyde at 7000 and 10,000 PPM were reduced to
below "faintly offensive" (Table 22). Strength was reduced,
but not as much as offensiveness. Control manure was
rated as "definite offensiveness" for quality and "definite
odor" for quantity. The apparent smell of formaldehyde at
30,000 PPM paraformaldehyde caused both odor offensive-
ness and strength to be above that of the lower two concen-
trations. Odor control with 30,000 PPM paraformaldehyde
must be considered inadequate. Personal evaluation indi-
cated paraformaldehyde was a better treatment in reducing
odor offensiveness in fresh manure than was acrolein or
H3PO4.

This reduction in odor offensiveness with the

lower two concentrations of paraformaldehyde can be

attributed to the prevention of odorous compound formation

124

by the bactericidal action of the formaldehyde. Also the
odor of formaldehyde may have masked the natural odor of
manure causing it to be less offensive to the odor panel.

This reduction in offensiveness relates to the
decreased ammonia concentration in the air above para-
formaldehyde treated manure, probably a result of decreased
degradation. In treatments where no reduction in degrada-
tion occurs there would probably be no decrease in the
amount of ammonia in the air over manure even though there
is a decrease in offensiveness. Therefore this method of
using ammonia as an odor indicator probably would not be
applicable in all cases.

Correlation coefficients between odor offensive-
ness and strength were r = +.66 and +.71 respectively
(Table 22 and 23). This indicates the odor panel could
not effectively separate the two, and this was observed by
Cole et a1. (1974). One reason for this might be the nose
becomes less sensitive after smelling an odor for a rela-
tively short period of time. Odor fatigue could also be
responsible for the large amount of variation in scores
assigned duplicate jars by the odor panel.

Because of the fairly high positive correlation
between offensiveness and strength only offensiveness was
evaluated in Experiments II and III. No consistent
depression of odor offensiveness was perceived with para-

formaldehyde in Experiment II, but there was a slight

125

depression in Experiment III. This indicates that para-
formaldehyde may not be effective in reducing offensiveness
of odorous compounds already produced, and agrees with Cole
et a1. (1975).

KMnO4 at 1000 PPM decreased odor offensiveness and
strength in fresh manure to the "faintly offensive" level
while control was rated above "definitely offensive"

(Table 23). Odor strength was reduced to just above a
"faint odor" compared to control of a "definite odor." In
decomposed manure KMnO4 treatment may have decreased
offensiveness slightly, but this depression is not certain
from odor panel results. Personal evaluation of decomposed
manure (Table 26) indicated KMnO4 decreased odor offensive-
ness within a few minutes after addition.

Odor changes after lime addition to fresh manure
was not evaluated, but Experiments II and III indicate
little effectiveness for lime in decreasing odor offensive-
ness in decomposed manure. Personal evaluation revealed a
strong smell of ammonia resulting from this treatment.

This odor to most panelists seemed just as offensive as

the natural odor. This is in contrast to what was observed
by Hammond et a1. (1966) and Day (1966) using liquid swine
manure.

Acrolein, H P04, NaClO and H 02 did not prevent

3 4 2

odor formation in fresh manure. Acrolein, H3PO4 and NaClO

were added to decomposed manure and a personal evaluation

4

126

made. No decrease in odor offensiveness could be detected
and these treatments were not further evaluated. H202
added to decomposed manure was evaluated with an odor panel
in Experiments II and III, and little if any decrease in
offensiveness was detected.

In the first three experiments no statistical dif-
ferences could be detected with various treatments. The
method of odor evaluation used in these first three
experiments resulted in an excessive amount of olfactory
fatigue and/or confusion of odor panelists. Therefore
means, personal evaluations and literature information were
used to determine which treatments would be tested in
Experiment IV. Paraformaldehyde, KMnO4 and H202 were chosen.

The method of evaluating offensiveness in Experi-
ment IV was one of relative offensiveness of two treatments
compared with control. Odor fatigue and panelist confusion
were reduced by decreasing number of jars evaluated at any
one time and in any one comparison.

Paraformaldehyde at 5000 and 10,000 PPM did not
decrease offensiveness at the intervals evaluated (Table
31). H202 at 500 PPM decreased offensiveness compared to
100 PPM H202 and control at nine to 15 hours (Table 32).
KMnO4 at 500 and 1000 PPM reduced odor offensiveness for
the duration of the experiment (eight days) (Table 33).

Decomposed manure was used in these evaluations.

127

Based on these results the least concentration of
additive that reduced odor was tested further. Paraformalde-
hyde did not reduce odor offensiveness, therefore the least
concentration was used based on results of Experiment I.

Paraformaldehyde at 5000 PPM added to decomposed
manure was more offensive than H202, KMnO4 and control
manures. Personal evaluation revealed a strong formalde-
hyde odor.

In a three-way comparison 500 PPM KMnO treated

4
manure was less offensive than paraformaldehyde, but not
different from control until day eight (Table 34). This
may be explained on the basis of a small difference between
KMnO4 and control manures when compared to paraformaldehyde

manure. In another three-way comparison KMnO treated

4
manure was less offensive than control after 36 to 40
hours, but not different than H202 manure (Table 36). At
day eight KMnO4 treated manure was less offensive than
both. Thus extent of odor offensiveness will depend to
some degree on treatments compared.

In another three-way comparison, 500 PPM H202
treated manure was less offensive than paraformaldehyde
manure, but no difference could be detected when compared
to control (Table 35). When H202 treated manure was
compared to KMnO4 and control manures no difference could
be detected until 36 to 40 hours when both treatments were

less offensive than control, but no different between

128

themselves (Table 36). At day eight H 02 manure was not

2
different than control.

These results indicate paraformaldehyde was not
effective in reducing odor offensiveness of decomposed
manure but probably enhanced it. KMnO4 reduced offensive-
ness possibly on a short-term as well as long-term basis.
H202 may have reduced odor offensiveness, but this odor
reduction is not certain.

Because the effect of H202 was equivocal at the
times evaluated an evaluation at 0.5 to 1.5 hours was then
made. At this time both 100 and 500 PPM H202 treated
manure were less offensive than control manure, but by
seven hours only 500 PPM treated manure was less offensive
than control (Table 37). By 30 to 32 hours no odor reduc-
tion was detected.

Odor of manure treated with 500 PPM H202 was less
offensive than KMnO4 or control manures at 0.5 to 1.5
hours (Table 38). At seven hours both treatment manures
had less offensive odor than control. At 30 to 32 hours
H202 treated manure was again less offensive than KMnO4
and control manure, but by day eight the KMnO4 treated
manure was less offensive.

In these trials KMnO was added as crystals to the

4

manure. The lag in odor reduction may be reduced by using

dissolved aqueous KMnO4. This agrees with the lag in

129

sulfide destruction after addition of KMnO4 observed by
Cole et a1. (1975).

A problem encountered in the last part of Experi-
ment IV was foaming caused by the highest concentration of
H202. This may have reduced offensiveness by trapping
odorous gases in the bubbles resulting in a decreased
offensiveness. The 100 PPM H202 caused a slight foaming.
Foaming as a result of addition of H202 was reported by
Hollenbach (1971). He indicated this could be prevented
by adding less concentrated solutions.

Results from these evaluations are not consistent
in all cases but H202 tended to be most effective in
reducing odor offensiveness on a short-term basis, possibly
up to 30 to 32 hours. Crystalline KMnO4 tended to con-
sistently reduce offensiveness for longer time periods
(eight days), and possibly for short periods.

Ritter et a1. (1975) found H20 at 12.5 PPM

2

decreased sulfide levels in liquid dairy manure but other
odorous compounds remained. Ninety percent of those odor

panelists rated manure with KMnO at 480 PPM to be "not

4
offensive" or "mildly offensive," and KMnO4 was effective
for at least 72 hours indicating a long-term reduction.
Cole et a1. (1975) found H202 and KMnO4
to reduce odor strength in liquid swine manure, but these

at 500 PPM

treatments added to liquid dairy manure showed little

improvement. The reason given for this was dairy manure

130

was judged to be much less offensive (faint to definite
offensiveness) than swine manure meaning a reduction in
offensiveness must be down to the "very faintly offensive"
range.

Both studies were done using an odor panel rating
manure as to strength or offensiveness on a one to ten
scale. Odor fatigue may have been a factor in producing
these inconsistent results.

Compounds found to be most efficacious were
paraformaldehyde added to fresh manure, H202 in decomposed
manure and KMnO4 to some degree in both.

For these compounds to be acceptable for use in
controlling odors from animal wastes they must not present
a problem when added to the soil. Neely (1966) stated at
low concentrations formaldehyde can serve as a substrate
for bacteria, and therefore will not accumulate in the soil
upon spreading. The concentrations of formaldehyde found
to be most effective in fresh manure was greater than that
evaluated by Neely. Therefore more evaluations would need
to be made before it could be assumed that this concen-
tration of formaldehyde would degrade. H202 will decom-
pose to water and oxygen both of which are innocuous

(Miner, 1974). Cole et a1. (1974) considered KMnO to be

4
safe since it is used in potable water treatment.

Addition of K+ to the soil as KMnO4 at 500 PPM

(0.257 pounds/ton) would not cause problems with toxicity

131

because most dairy manure contains over 5 pounds of potas-
sium per ton. Therefore KMnO4 additions would increase
potassium by only five percent. Effects of Mn addition to
soils are speculative.

Some of the manure used in Experiment IV was found
to contain fruit fly larva. Treatments containing para-
formaldehyde completely eradicated those present, but no
or H O .

4 2 2
Seltzer et a1. (1969) noticed flies, given the choice

decrease could be seen in jars treated with KMnO

between paraformaldehyde treated manure and untreated,
chose to deposit eggs in the untreated. This could be of
some value in preventing fly breeding in animal wastes.

H202, KMnO4 and paraformaldehyde currently cost
about $ .50, $ .70 and $1.90 per pound commercially. At
concentrations of 500, 500 and 5000 PPM respectively a cost
of $2.09, $2.91 and $72.90 respectively would be required
to treat 1000 gallons of liquid manure.

Miner (1974) estimated the average 1000 pound cow
produced 88 pounds of manure (urine and feces) per day.
This is about 16 tons of manure per year. To this about
3.2 tons of water per year (20 percent) will be added to
keep manure in a liquid form giving a total of 19.2 tons

of liquid manure per cow per year. H202, KMnO and para-

4
formaldehyde would cost $10.03, $13.97 and $350.02 respec—

tively to treat waste from each 1000 pound cow per year.

132

These calculations are assuming all manure will be
treated. In situations where only a small portion such as
a tank load is in need of treatment, H202 may be adequate
for short-term odor control when added directly to the
spreader wagon. This was tried by Kibbel et a1. (1972),
and found to reduce offensiveness of manure from liquid
manure tanks.

Experiment V was a preliminary trial evaluating
the commercial products Odor Mask, Sep-Zyme "O” and Pit-
Zyme. Results indicated 1430 PPM Odor Mask was more
offensive than other treatments or control. Sep-Zyme "O",
a dried enzyme, at 360 PPM did not decrease offensiveness.
Pit-Zyme, a dried enzyme, at 360 PPM did decrease offensive-
ness at day eight probably a result of odor masking.

Insufficient trials using definitive odor evalu-
ation techniques have been performed with this type of
product. Therefore any recommendations concerning

effectiveness would be strictly presumptuous.

VI . SUMMARY

H3PO4 and NaClO4 were slightly bactericidal when
added to fresh liquid dairy manure. Paraformalde-
hyde was bactericidal in fresh and decomposed dairy
manure for at least 22 days.

Paraformaldehyde, H3PO4 and NaClO4 tended to
decrease pH. KMnO4 in decomposed manure, but not
fresh, raised pH as did lime.

The pH of fresh liquid manure tended to decrease
with time while decomposed manure increased.
Ammonia (NH3) in the air space over fresh manure

as well as ammonia (NH3 and NH4+) dissolved in
manure was decreased by paraformaldehyde. Lime
increased the amount of ammonia (NH3 and NH4+)
dissolved in decomposed manure, but this relation-
ship was observed for only one day.

Odor panel results indicate paraformaldehyde at
7000 PPM may be adequate to prevent formation of
odorous compounds and reduce offensiveness in
fresh manure, but not in decomposed manure. H202

at 500 PPM reduced offensiveness on a short-term

basis, but results were compounded by foaming.

133

134

KMnO4 at 500 PPM was partially effective in fresh
and decomposed manure being most effective on a
long-term basis (eight days).

H202, KMnO4 and paraformaldehyde at above concen-
trations would cost $2.09, $2.91 and $72.90
respectively to treat 1000 gallons of liquid
manure.

H202 added to a spreader wagon may be the most
economical way to treat portions of manure when
there is no need to treat all of it. Foaming
problems may be overcome by adding as a dilute
solution. ‘

For situations where all the manure is in need of
treatment, KMnO4 may be the most effective although
slightly more expensive than H202. Best results
would probably be obtainedby adding to the manure
pit several days before spreading.

Paraformaldehyde was not an economical alternative,
but in situations where ammonia or fly breeding is
a problem it may be feasible when added to the top

layer of manure.

BIBLIOGRAPHY

BIBLIOGRAPHY

American Conference of Governmental Industrial Hygienists.
1967. Threshold Limit Values. Cited by J. R.
Miner. 1974. Odors from Confined Livestock Pro-
duction. Environmental Protection Technology
Series.

American Public Health Association. 1972. Methods of Air
Sampling and Analysis. American Public Health
Association. Washington, D.C.

American Society of Agricultural Engineers. 1973.
Structures and Environment Committee 412 Report.
Cited by J. R. Miner and R. J. Smith (Eds.). 1975.
Livestock Waste Management With Pollution Control.
North Central Regional Research Publication 222.

Amoore, J. E. 1963. Stereochemical theory of olfaction.
Nature 198:274.

Amoore, J. E., J. W. Johnston and M. Rubin. 1964. The

stereochemical theory of odor. Scientific American
210:42.

Amoore, J. E., G. Palmer and E. Wauke. 1967. Molecular

shape and odor: pattern analysis by PAPA. Nature
216:1084.

Backman, E. L. 1917. Physiol. Abstracts 2:479.

Baker, R. A. 1964. Response parameters including synergism-
antagonism in aqueous odor measurement. Annals of
the New York Academy of Sciences 116:495.

Barth, C. L. 1970. Why does it smell so bad? Amer. Soc.
Agri. Engin. Paper 70-416.

Barth, C. L., D. T. Hill and L. B. Polkowski. 1972.
Correlating 011 and odorous components in stored

dairy manure. Amer. Soc. Agri. Engin. Paper
72-950.

135

136

Bell, R. J. 1971. Aeration of liquid poultry manure: a
stabilization process or an odor control measure.
Poultry Sci. 50:155.

Benham, C. L. 1967. The effectiveness of caustic soda in
preventing the development of smell in poultry
droppings slurry pits. Report from National
Agricultural Advisory Service. Shardlow Hall.
Derby, England.

Bethea, R. M. and R. S. Narayan. 1972. Identification
of beef cattle feedlot odors. Trans. Amer. Soc.
Agri. Engin. 15:1135.

Blosser, T. H. 1964. The changing picture in animal
production. Proc. Pacific Northwest Animal Industry
Conf. Pullman, Washington.

Bronk, J. R. 1973. Chemical Biology. Collier-Macmillan
Publishers, London.

Burnett, W. E. 1969. Qualitative determination of the
odor quality of chicken manure. In: Odors, gases,
and particulate matter from high density poultry
management systems as they relate to air pollution.
Final Report Cornell University Agricultural
Engineering Dept.

Burnett, W. E. and N. C. Dondero. 1968. The control of
air pollution (odors) from animal wastes-
evaluation of commercial odor control products by
an organoleptic test. Amer. Soc. Agri. Engin.
Paper 68-909.

Cole, C. A., H. D. Bartlett, D. H. Buckner and D. E.
Younkin. 1974. Odor control of liquid manure
using chemical and biological treatments. Amer.
Soc. Anim. Sci. Paper 12a (abstr.).

Cole, C. A., H. D. Bartlett, D. H. Buckner and D. E.
Younkin. 1975. Odor control of liquid dairy
and swine manure using chemical and biological
treatments. In: Managing Livestock Wastes. Pro-
ceedings of the 3rd International Symposium on
Livestock Wastes. University of Illinois. P.
374.

Cole, C. A., H. D. Bartlett, D. H. Buckner and D. E.
Younkin. 1976. Efficacy of certain chemical and
biological compounds for control of odor from
anaerobic liquid swine manure. J. Anim. Sci. 42:1.

137

Connor, L. J., R. L. Maddex and L. L. Leighty. 1971.
Environmental quality legal considerations.
Michigan State University Extension Bulletin E-732.

Dale, A. C. 1971. Status of dairy cattle waste treatment
and management research. In: Animal Waste Manage-
ment. Proceedings of National Symposium on Animal
Waste Management. Warrenton, Virginia. P. 85.

Dale, A. C. and D. L. Day. 1967. Some aerobic decomposi-
tion properties of dairy cattle manure. Trans.
Amer. Soc. Agri. Engin. 10:546.

Dale, A. C., J. R. Ogilvie, A. C. Chang, M. P. Douglass
and J. A. Lindley. 1969. Disposal of dairy cattle
wastes by aerated lagoons and irrigation. In:
Animal Waste Management. Cornell University
Conference on Agricultural Waste Management.
P. 150.

Davis, J. T. and F. H. Taylor. 1954. A model system for
the olfactory membrane. Nature 174:693.

Day, D. L. 1966. Liquid hog manure can be deodorized by
treatment with chlorine or lime. Illinois Research.
127. Cited by J. R. Miner. 1974. Odors from
Confined Livestock Production. Environmental
Protection Technology Series.

Day, D. C., E. L. Hansen and S. Anderson. 1965. Gases
and odors encountered in confinement swine buildings.
Trans. Amer. Soc. Agri. Engin. 8:118.

Deibel, R. H. 1967. Biological aspects of the animal
waste disposal problem in agriculture and the
quality of our environment. (Ed.) N. C. Brady.
American Assoc. for Advancement of Science.
Publication 85. Washington, D.C. P. 395.

Dyson, G. M. 1938. The scientific basis of odour. Chem.
and Ind. 57:647.

Faith, W. L. 1964. Odor control in cattle feed yards.
Jour. Air Pollut. Control Assoc. 14:459.

Fisher, L. J. 1974. Influence on feeding system,
digestibility of ration and proportion of concen-
trate consumed on the quantity and quality of
excreta voided by lactating cows. In: Processing
and Management of Agricultural Waste. Cornell
Agricultural Waste Management Conference. P. 283.

138

FMC Corporation. (date unknown). Hydrogen peroxide
control of sewage hydrogen sulfide.

Fosnaugh, J. and E. R. Stephens. 1969. Identification
of Feedlot Odors. Final Report. Dept. HEW, PHS
Grant Number UI 00531-02. Statewide Air Pollution
Research Center, University of California, River-
side.

Foster, D. 1964. Odor correlation and the panel technique-
1953. Annals of the New York Academy of Science
116:482.

Geldreich, E. E. 1966. Sanitary significance of fecal
coliforms in the environment. 0.5. Dept. of the
Interior, Federal Water Pollution Control Adminis-
tration, Water Pollution Control Research Series.
Cited by J. R. Miner and R. J. Smith (Eds.). 1975.
Livestock Waste Management With Pollution Control.
North Central Regional Research Publication 222.

Gerrish, J. B. 1974. Composition of waste as excreted
changes during storage, and odor development.
In: Michigan State University Agricultural Waste
Conference. P. 21.

Grub, W., R. C. Albin, D. M. Wells and R. Z. Wheaton. 1969.
The effect of feed, design, and management on the
control of pollution from beef cattle feedlots.

In: Animal Waste Management. Cornell University
Conference on Agricultural Waste Management. P.
217.

Guadnagni, D. G., R. G. Buttery, S. Okano and H. K. Burrn.
1963. Additive effect of sub-threshold concen-
trations of some organic compounds associated with
food aromas. Nature 200:1288.

Guyton, A. C. 1971. Textbook of Medical Physiology.
W. B. Saunders Company, Philadelphia.

Hammond, W. C., D. L. Day and E. L. Hansen. 1966. Treat-
ment of liquid hog manure to suppress odors. Amer.
Soc. Agri. Engin. Paper 66-928.

Hart, S. A. 1960. The management of livestock manure.
Trans. Amer. Soc. Agri. Engin. 3:78. Cited by
J. R. Miner and R. J. Smith (Eds.). 1975.
Livestock Waste Management With Pollution Control.
North Central Regional Research Publication 222.

139

Hartung, L. D., E. G. Hammond and J. R. Miner. 1971.
Identification of carbonyl compounds in a swine-
building atmosphere. In: Proceedings International
Symposium of Livestock Wastes. Ohio State Univer-
sity. P. 105.

Hashimoto, A. G. and D. C. Ludington. 1971. Ammonia
Desorption from concentrated chicken manure slur-
ries.) In: Proceedings International Symposium of
Livestock Wastes. Ohio State University. P. 117.

Haye, U. 1973. The use of ozone generators in broiler
houses. Contact Meeting of Researchers on Manure,
Liquid Manure and Smell Problems. Wageningen.
P. 35.

Hollenbach, R. E. 1971. Manure odor abatement using
hydrogen peroxide. Report 5638-R. Food Machinery
Corporation. Princeton, N.J. Personal Communi-
cation. Cited by J. R. Miner. 1974. Odors from
Confined Livestock Production. Environmental
Protection Technology Series.

Ifeadi, C. N., E. P. Taiganides and R. K. White. 1975.
Quantitative measurement and sensory evaluation of
dairy waste odor. In: Managing Livestock Wastes.
Proceedings of the 3rd International Symposium
on Livestock Wastes. University of Illinois.

P. 354.

Jacobs, M. B. 1960. The Chemical Analysis of Air Pollu-
tants. Interscience Pubs. Inc., New York, N.Y.
Cited by J. R. Miner. 1974. Odors from Confined
Livestock Production. Environmental Protection
Technology Series.

Jongebreur, A. A. and M. van Geelen. 1974. Possible ways
of abating the nuisance of smell caused by live-
stock and poultry farms. In: Processing and
Management of Agricultural Waste. Cornell Agri-
cultural Waste Management Conference. P. 533.

Jones, D. D., D. L. Day and A. C. Dale. 1970. Aerobic
treatment of livestock wastes. University of
Illinois Bulletin 737.

Kendall, D. A. and A. J. Neilson. 1964. Correlation of
subjective and objective odor responses. Annals
of the New York Academy of Science 116:567.

140

Kibbel, W. H., Jr., C. W. Raleigh and J. A. Shephard.
1972. Hydrogen peroxide for pollution control.
In: Proceedings of the 27th Purdue Industrial Waste
Conference.

Loehr, R. C. 1968. Pollution Implications of Animal
Wastes-A forward Oriented Review. U.S. Dept. of
the Interior Federal Water Pollution Control
Administration.

Loehr, R. C. 1974. Agricultural Waste Management.
Academic Press, New York.

Ludington, D. C., A. T. Sobel and B. Gormel. 1969. Control
of odors through manure management. Amer. Soc.
Agri. Engin. Paper 69-936.

Ludington, D. C., A. T. Sobel and A. G. Hashimoto. 1969.
Odors and gases liberated from diluted and undi-
luted chicken manure. Amer. Soc. Agri. Engin.
Paper 69-426.

Merkel, J. A., T. E. Hazen and J. R. Miner. 1969. Identi-
fication of gases in a confinement swine building
atmosphere. Trans. Amer. Soc. Agri. Engin. 12:310.

Miller, R. G. Jr. Simultaneous Statistical Inference.
McGraw-Hill Book Co., N.Y. P. 67.

Miner, J. R. 1970. Raising livestock in the urban fringe.
Agri. Engin. 51:702.

Miner, J. R. (Ed.). 1971. Farm Animal—Waste Management.
North Central Regional Publication 206.

Miner, J. R. 1974. Odors from Confined Livestock Pro-
duction. Environmental Protection Technology
Series.

Miner, J. R. and T. E. Hazen. 1969. Ammonia and amines:
components of swine-building odor. Trans. Amer.
Soc. Agri. Engin. 12:772.

Miner, J. R., M. D. Kelley and A. W. Anderson. 1975.
Identification and measurement of volatile compounds
within a swine building and measurement of ammonia
evolution rates from manure-covered surfaces. In:
Managing Livestock Wastes. University of Illinois.
P. 351.

141

Miner, J. R. and R. J. Smith (Eds.). 1975. Livestock
Waste Management With Pollution Control. North
Central Regional Research Publication 222.

Miner, J. R. and R. C. Stroh. 1975. Controlling feedlot
surface odor emission rates by application of
commercial products. Amer. Soc. Agri. Engin.
Paper 75-4566.

Mitchell, M. A., K. S. Konigsbacher and W. W. Edman. 1964.
The importance of odor as a nonfunctional component
or odor-a tool of marketing. Annals of the New
York Academy of Science 116:685.

Moncrieff, R. W. 1946. The Chemical Senses. Leonard
Hill, London.

Moncrieff, R. W. 1966. Odour Preferences. John Wiley,
New York. Cited by J. R. Miner. 1974. Odors from
Confined Livestock Production. Environmental
Protection Technology Series.

Morrison, S. M., D. W. Grant, M. P. Sister and K. Elmund.
1969. Role of excreted antibiotic in modifying
microbial decomposition of feedlot waste. In:
Animal Waste Management. Cornell University Con-
ference on Agricultural Waste Management. P. 336.

Moulton, D. G. 1970. Detection and recognition of odor
molecules. In: Gustation and Olfaction. (Eds.)
O. Ohloff and A. F. Thomas. Academic Press, New
York.

Neely, W. B. 1966. The adaption of Aerobacter aerogenes
to the stress of sublethal doses of formaldehyde.
Jour. Gen. Micro. 45:187.

 

Ogilvie, J. R. and A. C. Dale. 1971. Short term aeration
of dairy cattle manure for irrigation. In: Pro-
ceedings International Symposium of Livestock Wastes.
Ohio State University. P. 283.

O'Neil, E. T. 1972. Manure odor abatement with hydrogen
peroxide. Report 4760-R. Food Machinery Corpora—
tion. Princeton, N.J. Personal Communication.
Cited by J. R. Miner. 1974. Odors from Confined
Livestock Production. Environmental Protection
Technology Series.

142

Ritter, W. F., N. E. Collins and R. P. Eastburn. 1975.
Chemical treatment of liquid dairy manure to reduce
malodors. In: Managing Livestock Wastes. Pro-
ceedings of the 3rd International Symposium on
Livestock Wastes. University of Illinois. P. 381.

Sawyer, C. N. 1970. The nitrogen cycle. In: Nitrate
and Water Supply: Source and Control. Proceedings
University of Illinois 12th Sanitary Engineering
Conference. P. 6.

Schultz, H. G. 1964. Odor theory, physiology, and
chemistry-1953. Annals of the New York Academy of
Science 116:378.

Seltzer, W., S. G. Moum and T. M. Goldhaft. 1969. A
method for the treatment of animal wastes to con-
trol ammonia and other odors. Poultry Sci. 48:1912.

Sheehy, J. P., W. C. Achinger and R. A. Simon. (undated).
Handbook of Air Pollution. Environmental Health
Series, Air Pollution. Cited by J. R. Miner.
1974. Odors from Confined Livestock Production.
Environmental Protection Technology Series.

Siegel, S. 1956. Nonparametric Statistics for the
Behavioral Sciences. McGraw-Hill Book Co., N.Y.
P. 75.

Skarp, S. 1975. Manure gases and air currents in livestock
housing. In: Managing Livestock Wastes. Proceed-
ings of the 3rd International Symposium on Live-
stock Wastes. University of Illinois.

Sobel, A. T. 1969. Removal of water from animal manures.
In: Animal Waste Management. Cornell University
Conference on Agricultural Waste Management. P. 347.

Sobel, A. T. 1970. Olfactory measurement of animal manure
odor. Amer. Soc. Agri. Engin. Paper 70-417.

Sobel, A. T. 1971. Moisture removal. In: Agricultural
Wastes: Principles and Guidelines for Practical
Solutions. Cornell University Conference on
Agricultural Waste Management. P. 107.

Sobsey, M. D., C. Wallis and J. L. Melnick. 1974. Chemical
Disinfection of Holding-Tank Sewage. Applied
Microbiology 28:861.

143

Stephens, E. R. 1971. Identification of odors from cattle
feedlots. California Agriculture 25:10.

Stern, A. G. 1968. Air Pollution. Vol. II. Academic
Press, New York. Cited by J. R. Miner and T. E.
Hazen. 1969. Ammonia and amines: components of
swine-building odor. Trans. Amer. Soc. Agri.
Engin. 12:772.

Stombaugh, D. P., H. S. Teague and W. L. Roller. 1969.
Effects of atmospheric ammonia on the pig. J.
Anim. Sci. 28:44.

Summer, W. 1971. Odour Pollution of Air-Causes and
Control. Leonard Hill Books, Cleveland.

Taiganides, E. P. and R. K. White. 1968. The Menace of
noxious gases in animal units. Trans. Amer. Soc.
Agri. Engin. Paper 68-557.

Ulich, W. L. and J. P. Ford. 1975. Malodor reduction in
beef cattle feedlots. In: Managing Livestock
Wastes. Proceedings of the 3rd International
Symposium on Livestock Wastes. University of
Illinois. P. 369.

Veloso, J. R., P. B. Hamilton and C. R. Porkhurst. 1974.
The use of formaldehyde flakes as an anti-
microbial agent in built-up poultry litter.
Poultry Sci. 53:78.

Weast, R. C. (Ed.). 1972. Handbook of Chemistry and
Physics. The Chemical Rubber Co., Cleveland.

Wells, D. M., G. F. Meenaghan, R. C. Albin, E. A. Coleman
and W. Grub. 1972. Characteristics of Wastes from
Southwest Beef Cattle Feedlots. In: Waste Manage-
ment Research. Cornell Agricultural Waste Manage-
ment Conference. P. 385.

White, R. K. and E. P. Taiganides. 1969. A procedure to
identify malodors from animal wastes. Amer. Soc.
Agri. Engin. Paper 69-425.

White, R. K., E. P. Taiganides and G. D. Cole. 1971.
Chromatographic identification of malodors from
dairy animal waste. In: Proceedings International
Symposium of Livestock Wastes. Ohio State
University. P. 110.

144

Winslow, C. E. A. and D. Greenberg. 1918. Proc. Soc.

Wright,

Yushok,

Exp. Med. 15:123.

R. H. 1964. Odor and molecular vibration: the
far infrared spectra of some perfume chemicals.
Annals of the New York Academy of Science 116:552.

W. and F. E. Bear. 1948. Poultry manure. Its
preservation, deodorization and disinfection. New
Jersey Agric. Expt. Sta. Bulletin 707. Rutgers
University. New Brunswick, N.J. Cited by J. R.
Miner. 1974. Odors from Confined Livestock
Production. Environmental Protection Technology
Series.

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