. a 7
'5‘ 3‘: ¢~ ‘ER "‘1‘ .. 3‘3"
;..3 “a «.1 1 . ‘;a J ‘- s
Q'Hw1'6 .' .0 .3 . .
5 ”of -\ L U‘
'8 9‘ M
"u ’f‘ (‘fi kc, “’ ‘ . 4 '.
3 .1“ “is ‘ ,
) “3 54.) «5‘ 1“; 3;.

\ ma («:1 ..:'.x.";:='=£-
GQEHMESG '4'

‘ '. "4i 9’

ft .q‘f ( kgaaf
'3‘“! rig 155:. iA‘ ‘fi‘r‘fi
ugly»:

rm

 

Thislstoeerttfgthatthe

thesis entitled
AN INVESTIGATION OF A CONTINUOUS PRCCESS FOR

THE FLASH DRYING AND GRINDING 0F ALFALFA

presented by

CLYDE G. ANDERSON

has been accepted towards fulfillment
of the requirements for

411“,“ mmFfly-

/ Major professor

 

Date Jul} 16 :5"

 

 

 

 

AN INVESTIGATION OF A CONTINUOU3 PROCESS IOR
THE FLASH DRYING AND GRINDING 0F ALFALFA

By

CEYDE G. ANDERSON

A THESIS

Submitted to the School of Graduate Studies onMichigan
State College of Agriculture and Applied Science
in partial fulfillment of the requiremente
for the degree of

IMASTER OF SCIENCE

Department of Chemical Engineering
'1951

-*

0"»

,
\J.-J

1; .1)

 

 

ACKNOWLEDGMENT

The author is greatly appreciative of the help
given by Professor J. W. Donnell, Chemical Engineering
Department Michigan State College. Appreciation is also
extended to E. J. Benne, Ph.D.,.Prefessor (research),
Agriculture Experiment Station, Michigan State College.
‘The author would also like to thank‘Wilbur‘W..Kennett for
his contribution to the design and construction of the

equipment used.

TABLE OF CONTENTS
Page

Introduction ................................. I
History ...................................... 3
Equipment ;.................................... 6
Procedure

Preparation of alfalfa .................. 15

Run Procedure ........................... 15

Analysis for carotene content ........... 18

Moisture determination .................. 20
Data

Capacity of runS......................... 21

Carotene analysis ........................26
Calculations ................................. 30
Discussion ................................... 33
Conclusion ................................... 37

Bibliography eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeoe 38

VIOAC'.....'.‘.'9..O‘.

‘ d O J

’70.~~-”.I..

INTRODUCTION

This investigation of the flash drying of alfalfa
had two objectives; first, to determine the capacity of the
pilot plant and the limiting factors on the capacity;
second, to determine the effect of this method of drying on
the retention of carotene in the dried product.

The flash drying of alfalfa is accomplished by intro-
ducing hot flue gases directly into the grinding chamber of.
a hammer mill where a large percentage of the drying occurs.
As the alfalfa is reduced in size. a large area of wet sur-
face is exposed to the hot gases entering the mill.

Exposure of this surface enables the rapid drying of the
alfalfa. Further drying is accomplished in the elutriator
and cyclone. , p _

In the second phase, antioxidants were mixed with the
green feed to determine if the amount of carotene retained
in the product could be increased._

The number of antioxidants used waslimited to four,
which were known to be good inhibitors to the destruction
of carotene in alfalfa meal. The antioxidants were selected
from those used by C. Ray Thompson‘l) in his work on alfalfa

meal.

Artificial drying of alfalfa is of particular advan-

tags in that the crOp can be harvested early in the season

when its food value is the greatest. Late cuttings have
a high content of indigestible wood fibers, low carbohy-
drate, protein, and vitamin content. Instead of leaving
the alfalfa reach this condition more frequent cuttings

can be made and dried, thus retaining the food value of
the f.°d e

HISTORY

‘Work was begun in 1950 on a process for the simul-
taneous grinding and drying of alfalfa by‘Wilbur‘W.lKennett(2).
His work was limited to the mass transfer and.mass transfer
coefficients while drying and grinding alfalfa. The equip-
ment at that time necessitated batch operations as there was
no method of recycling part of the ground and dried.neal.

It was found that green alfalfa of 80%:moisture clogged the
mill and it became necessary to mix dried meal with the green
feed to bring the moisture down to at least 35%gbefore the
mill would continue to Operate without clogging. In the
initial operations this was accomplished by mixing dried
meal with.the green feed and then introducing this mixture

to the mill. Redesign and addition of equipment enabled the
recirculation of coarse meal to the hammer mill where it was
mixed with the green feed entering._ Further discussion of
this will be made under "equipment".

To the authorfs knowledge, there is no commercial
application of the type of equipment used in this investiga-
tion to the drying of alfalfa. Other types of driers of the
drum and conveyor type are being used in commercial driers.

In these type driers the alfalfa is dried as it comes from the
field. Ne attempt is made to take advantage of the more rapid
drying rates obtained when the alfalfa is ground and a large

surface area exposed to high temperature gases.

., . x
at
e’ . IV
. \_-
|rs\'
II
..
I I
...
v\
x
A
1
\
g.“ s .i
G
I '7
,

«‘9

Jo

 

.
- r»-.. i. . _- _. i . ,.
A - o . ‘4’ . .
‘
.. .
.I as- La- .5 ‘v ‘ a A. \ u
.
l
. l
\l v -.. \s \. u. u .. .e
. ' n
A L\. Ala-.ag ~ in MAL
. , l r
h
‘ er; a 4- " 5 -¢
. . . .
x .. ‘a a i L A l s
. ' ;~_
. I .- .
‘ - \‘J \-..\.I . \.'\1 g
. v . r -‘
g _ 5'\ be .l g J .Il
V . .
' 0
. _ _ ‘
. . i . ,
. -a
I
. “A , ‘ f "
I
. ' — I ,-
in l '
, J ' s _ t t. ’
e G
. ‘,
, r- 5 -.- .
t
. .
a
-O
I b
a) 7 ' . l
J
. f
‘l
.. _ I
I
. ~ . .
‘ 5 v’\ , '.
‘ C , a
. s _. o s
. '- .
. a .. ‘. .

Considerable work has been done to determine the
cause of the breakdown of carotene. In 1928 Bohm and.Haas
reported that seeds of legumes contain an enzyme which had
the ability to oxidize carotene and unsaturated fats.

Taubor describes an experiment proving that a carotene
oxidase does not exist and that the oxidation of carotene is
caused indirectly by an ”unsaturated fat oxidase”. Results
of this experiment show that the oxidation of carotene is
dependent on the shmultaneous oxidation of unsaturated fats(3).

further work by H.JH. Strain proved Tauber's theory“).
Carotenoid pigments or Vitamin.A present in unsaturated fats
are oxidized by intermediated products, not by direct enzymatic
action, nor by the relatively stablo"fat peroxides". ~the un-
saturated fat oxidase has been detected in various logunes
including alfalfa. Tho oxidase has been found to oxidize only
those compounds containing Igjf g (CH2)7C(O)fgroup with Cise
configuration. For example cleic, ricinoleic, linoleic, and
linoleic acids and their esters absorb oxygen very rapidly.

According to work by Silker(5), blanching fresh green
alfalfa with steam.prior to drying furnished complete protection
for the carotene. Also considerable protection was afforded
by certain antioxidants applied to fresh ground alfalfa. The
above work was done on a tray drier ‘t.65 degrees centigrade.

Silker also reports that grinding is detrimental to tho reten-
tion of carotene. This is due to the large amount of surface

r I . “
‘ c
» r A a. - - u- - . O a .—
. . .- .- ‘ -- . i a J . .. . .'
. .a, .. ‘ I I ‘3‘ .
.
u ‘ I ‘
.. ‘ .n. v .. . \J -A - . -a. A
..
. _ .
| . . . , J 1 ‘ .‘. t . i _ a .. \ v
.
a e ‘ O ‘ - . \J Al-
I
' ‘w
. . - ... A‘ .1 .. . ._ .. Eu ..
. ‘ \ — A - .. z. .. . _ . .
1
v Q
; v - .
- ,-\1 . 1.. ) is 4-. J .1 _. ~ an.
o
- ,e' , ‘ 4 _, _
.
s ‘-
. o ‘ ‘ D ' .
~ \
A . '
‘
o r I l
...
n I ~
I , l- 1 ' '
, . ‘ s . ‘ s ‘
1 . . .
. . - . . .
' O
‘ a
I
' u
.-
' _ e
C - l
. s ‘ ' ' ' ,-~ .. _ .
,' h
, ,
l 5 v
A , k‘ . . a \- - b

.L a,

l."

_.L

a . -
..
I
A -. \
4 sf
. ,- s
a. I
\’ d
\a l a-
. l .
' U s
.
1/ .
_.
.
.
pa...‘

g,

.
I.
._
n .r a‘ .
Q
.‘
A.

U an.

1
,4
e
.
I
O .
.
.
u
.
‘ a
~ a
V

. r .

Q

n

 

~

,1

’.
._.
.
.
I
. o

a
.n
a
a
,
A
h .

 

 

exposed for the oxidation to occur in.

C. Ray Thompson(1)has done considerable work on the use
of antioxidants to stabilize the carotene in alfalfa meal. In
this work he used alfalfa meal which had been previously dried.
The meal was treated with various antioxidants and solvents.
The samples were stored under controlled conditions for seven
and fourteen days at 65 degrees contigrado to promote the
rapid deterioration of carotene in the meal. The samples were
then analyzed for carotene content.

Of the 5b antioxidants used in Thompson's work, 2 ,5 di-
substitutod hydroquinones, p substituted phonylono-diaminos
and 2,2,4 trhsethyl-l,2-dihydroquinolino were the most active
compounds tested for stabilizing carotene in alfalfa. “Vege-
tableoils plus acetone were superior to alcohols, collosolvo,

or kerosene as carriers for the antioxidant.

 

EQUIPMENT

The equipment used in this work is as follows:

McCormick Deering Hammer Mill No. h-o complete with
MONO]? o

Specifications for hammer mill

Speed, full load 2980_
Diameter of rotcruhammers extended 12 in.
Power 5 EJ’.
Grinding plate area 123 sq. in.
Screen area 1L8 sq. in.
Total grinding area“ 271 sq. in.

Blower fan 1 3/8 in. dia., 5 wings 3/16 in. wide
Pipe size A in._
Cyclone dia. lt.5 in., overall height 36 in.
Hay ch0pper
Elutriator ‘
Surface cambustion burnerusing 35 psi using propane
Temperature recording galvanometer
Chromel-alumel thermocouples

wastinghouse type T.A. Industrial Analyzer, P.F.,
volts, amperes, and kilowatt meters

Scales to weigh feed used per run
Chainomatic analytic balance CM 55A
Drying oven 120 degrees centigrade
Spray gun for applying antioxidant

Equipment for analyzing for carotene
High speed agitator
Conco analytic balance
Refluxing equipment (condenser and erlynmeyer flasks)
Buohner funnel
Separatory funnels
109 ml volumetric flasks

Photwmeter

Filters #ZAB. #396. #55h

Chemicals required for analysis
Acetone
Petroleum.ether '
Ba(QH)2.8320 and NaOH solution
90% methyl alcohol-saturated with petroleum ether

(Na)2SOh_anhydrous

 

Photograph 1

Photograph 1 is an overallvieW'of the equipment

[‘11

used in this investigation. ine furnace with burner is
shown in the foreground with mill directly'behind.
Directly above the mill is the elutriator which separates
the coarse material for recycle from the'fine .meal
which is carried over to the cyclone. The meal settles
out in the cyclone and is collected in sacks attached
to the bottom of the pipe below the cyclone. Gases
from the cyclone are carried through a stack to the
roof of the building. Exhaust fan is shown in the
background to the left, and temperature recorder to the
right.

The furnace is covered with asbestos to prevent
loss of heat. The amount of excess air is controlled
by removing bricks from the front of the furnace.

Baffles were installed in the furnace to shorten the

flame length.

10

Photograph 2 is a close up view Of mill with top
gas inlet from furnace to mill. The strip of sheet metal
with the slot in it, which is shown in the front of the
shield around the mill, is a damper control for regulat-
ing the size of the Opening of the bottom gas inlet to the
mill.

The hay chopper with motor and gear arrangement
may be seen in back of the mill. This hay chopper
‘was made from a lawn.mower, and was used to cut the
green alfalfa into short lengths.

The thermocouple terminal bar is shown.attached to

the shield around the mill.

 

photograph 2

Photograph 3 is a view from the hopper side of
the mill where material is fed into the mill. Above
the hopper may be seen the arrangement used to maintain
a .seal at the bottom of the elutriator. By regulating
the hinged door, enough recycle was kept backed up to
prevent gases from being blown out at this point.

In the background, upper left corner, the drying

ovens for determining moisture content are shown.

 

Photograph 3

Photograph h is a view of the hammer mill when
opened'up. The hammers and screen.may be seen. In
front of these is the blower. The white lines are

thermocouple leads.

 

Photograph h

13

The following diagram illustrates the design of the
equipment. Cases are pulled through the furnace by the
blower fan. Part of the gases pass over the tOp, directly
into the hammer mill. The rest enters through the bottom
inlet below the hammer mill screen. The amount of gas
entering the bottom was controlled by the damper shown.
The feed mixture passes through the screen and is carried
up into the elutriator where it strikes a baffle which
distributes the meal in the elutriator. A reduction
in gas velocity allows the coarser material to settle
out and be recycled. The finer meal is carried up
through the elutriator to the cyclone. By varying the
position of the ”damper recycle control", the velocity
of the gases is varied and the size of the meal which

can be carried over is controlled.

DIAGRAM OF EQUIPMENT SHOWING FLOW OF GAS-<15

___

{//'rrr—"‘—’ to cyclone
TELUTRIATOR - a f
\ ' ‘

l
inner shell-—~——~——-__.\\+§4
damper recycle control _____._|

 

\

 

 

baffle. ~- — -____ --,
rficycle return -._l__l__m

air lock control~

 

 

 

 

 

 

 

 

 

 

 

feed hOpper _.-__
tap gas inlet _ _
h - came MILL
/
E} f mom
1
FURNACE

 

 

 

 

bottom gas inlet J

X's mark the location of thermocouples

15

PROCEDURE

‘WITHOUT ANTIOXIDANT

The mill was started cold. and dry recycle material
was fed into the mill. “When the recycle was circulating
smoothly, green alfalfa was fed to the chapper and then to
the mill hopper where it was mixed manually with the recycle
from the elutriator. Recycle and green mixture was then fed
into the mill continuously.A As soon as the green feed began
entering the mill the furnace was started. The feed1mixture
was fed slowly at first until the equipment got upto heat -
about 7 or 8 minutes. It is important that the furnace be
started after the greenfeedbegins to enter the mill since
the hot gases hitting the dry recycle material can ignite this
material. ”The presence of green feed eliminates this danger
due to the large amount of water in the feed which is vaporized
by the hot gases, thus cutting the temperature to a point where
the dry meal will not be ignited. A I

The amount of recycle was controlled by a damper effect
on the elutriator which in effect controlled the velocity of
the gases through the elutriator. Opening of the damper cut
down the velocity. allowing more material to settle out, giving
more recycle. Closing the damper increased the velocity, thus
more material was carried over into the cyclone. An air seal

of dried recycle was maintained at the bottom.of the elutriator.

This was controlled by hand Operation by the persen mixing and
feeding the alfalfa into the hammer mill. A fairly constant
feed rate was maintained by noting the load as indicated by the
power analyzer and regulating the feed rate to maintain a con-
stant lead.

Temperatures of gases entering hammer mill and leaving
the blower were noted during the run, and the furnace was:
regulated to maintain the temperature.

Fifteen to 20 pounds of recycle appeared to be the ideal
amount of material recirculating. When smaller amount was used.
the operation was not smooth and it was difficult to maintain
a seal at the bottom.of the elutriator. ‘The smaller amounts of
recycle used in some of the runs were used so that the recycle.
material would have less effect on the carotene in the product.

The rate of recycle was determined by drawing offa ‘
sample for a measured length of time and weighing this amount.
Care was taken to have the recycle Operating smoothly while
drawing the sample. The weights of green feed and recycle ‘
introduced were taken before the run. Time to make the run,
temperature of entering and leaving gases, and the power used.
'were noted during the run. At the end of the run, the weights
of product and recycle left in the mill were recorded. Samples
for carotene analysis were taken at the end of the run and.

placed hnmediately in cold storage at 3 degrees centigrade.

i
. ' V
. ,
.
v
o
V A
v ‘
. a ‘ .
I
a
v
a

e | .' v V ¢ --
. 1
.- D \ - -- ‘
.
v ,. -I ,v c
‘ ‘ ‘ .. . .
‘ s < i l o J. '
.
~_ _ ". ' --
4
- I..-
u .l l ‘ .
s .1 .. » x -' ' ‘
a.
I . .' ' ‘ ’
:I t ‘ . 1‘
.
,
- . .-. ~l ‘
, .
.
H . a b
.
7 . . ,
n ’ V
I d
‘ - t l "
' D
. . .
1 - . .
. . I ‘ -
a J - . a a
.
.A

I
,_ '7 . n v
. . 7- ..
e
. .
. - . .

a

A .

I " >

. . .
~ .9
. g '

._
b ' I
. . ». . , I '
. v ‘ ' ~

. . u -

.
.
.‘ e e a ‘
.
1 . ‘

’1 ""
:r‘ ‘
‘ I
R a. u h
' 2
’ .
l I,
‘ .
'_ . a
. . w-
.
.
' U
..
.
.. .
x , - -
‘
.
. _
.
4 ... ~
7\
. 4
I '
r ‘ ‘
. v
.
.
. ‘
.

,
._ e
,u
.
t
I
a
J.
A 1

 

 

 

17

At the end of a run it is necessary to shut off the
furnace and mill immediately. Failure to do this within a
minute or two would result in the dry meal being ignited.
Even after the furnace is shut off the fan in the mill pulls
enough heat from the hot walls of the furnace to cause ignie
tion of the dry meal. Therefore the mill was shut off at the

same time as the furnace and allowed to cool before cleaning

in preparation for the next run.

PROCEDURE WITH ANTIOXIDANT RUNS

.The alfalfa for_the run was first chopped into lengths
that averaged one inch. The material for the whole run was
then sprayed and thoroughly mixed with the antioxidant.
Enough antioxidant was applied.to make the concentration of
the antioxidant 0.25% of the feed on a dry basis. The pre-
pared alfalfa was then run as described above and samples
taken and stored in a refrigerator until the analysis of
carotene content was made.
Preparation‘gfvnntioxidant

A solution of 100ml of soybean oil and lOOml of acetone
was made. To this. 10 grams of antioxidant were added. The
resulting solution thus made up contained .05 gm/ml. The
‘weight of the green alfalfa wastaken and the weight on a dry
basis calculated. Enough of the antioxidant solution was
sprayed on the alfalfa to produce a concentration of 0.25%

antioxidant.

 

 

 

V.s

.
- c A
d I
r
I .t
.1.. .
of.
.I
..J
A...
.r v
r .‘
r
. s.‘
. a
if
I
. .,
.I .
.
... r
I
.
M
.
. a
‘.
u .
.
.
.
. .
.. . t.
4’.
a
.
s
d v
a. . .
N.
n .
4,
e
a
h
.
.

 

18

PROCEDURE FOR ANALXSIS OF CAROTENE

JMethods of analysis for carotene are not exact. In
this work two analysis of each sample were made and an aver-
age taken. Because of the lack of stability of the carotene,
the samples were stored at 3 degrees?until analysis were run.
All analysis in this work were runrwithin a week after the
material was dried. ‘

.A phasic separation was used to purify the carotene
solution in preparation for indexing on a calorimeter.

Filters #ZLB and #396 were used to determine the Chlorophyll_
correction to be applied to the readings using a.#55b filter.
The colorimeter had previously been calibrated against
standard solutions of known carotene content. Comparison of
the sample readings with the readings obtained with standard
solutions enabled the determinations of carotene content of
the sample.

_ The method used is the same as that used by the . ‘
Agriculture Experiment Station at Michigan State College. The
calorimeter and conversion charts used were those of the above
~experiment station.

A detailed procedure of the method of extraction and

purification of carotene from the alfalfa sample is as follows:

l9

CAROTENE ANALYSIS IN ALFALFA

‘Extraction from.fresh alfalfa.

' Whigh out a h gram sample and place in a Erlynmeyer
flask. Add.85 ml of undiluted Acetone and agitate vigor-
ously for A minutes. (A.meohanical agitator was used to
break up the fibers). To this, add 15 ml of aqueous sol. of
Ba(QH) and.NaOH (App. 353 Ba(OH) .83 20 and 10g Na OH(L).
The agitation may be eliminated.w en extracting from dried
meal. Use a 2 gram sample of dried meal.

Reflux the sample for 30 minutes using a water bath.
Agitate the mixture occasionally during refluxing. Cool after
finishing refluxing.

Filter through a buchner funnel using vaccums ‘Wash
flask and fibers with 85% Acetone until all traces of yellow
pigment are removed. Transfer filterate to a Separatory funnel.
‘Wash flask to remove all color traces using 85% Acetone.

Add (50 m1) petrOleum.ether, agitate gently, allow
phasic separation to occur. The product in the other layer
will be largely the carotenes, though Chlorophylls and '
Innthophyl s will also be present. Remove the Acetone layer,
wash with pet. ether. The pet. ether layer is added to the
first extraction. The Acetone layer is then discarded.

Add (30 ml) methyl Ale. to the ether solution. Chloro-
phylls and Ianthophylls are selectively absorbed by the alcohol
and phasic separation is made. wash the ether sclution, making
separations until the alcohol layer is colorless. Add a small
amount of pet. ether to alcohol solution to absorb any carc-
tene that may have passed into that solution. Add this to the
ether solution.

Filter the ether solution into a 100 ml measuring flask.
wash filter paper carefully with pet. ether. Also separatory
funnel. Make up solution to 100 ml.

Analyze the above solution using calorimeter. If
Chlorephylls are present apply correction to readings obtained.

20

MOISTURE DETERMINATION

The moisture in the green feed, recycle, and product
was determined by accurately weighing 5 gram samples of. each,
and then drying'at 120 degrees centigrade until they came to
constant weight. w .

Since the recycle rate was known and also the green
feed rate, the moisture in the feed mixture could be deter-
mined.

For Example: . . _ d .

Green feed rate l.38#/minute at 8l.2% moisture

Recycle rate 9.8‘5f/minute at 9.62% moisture

l. 38 I 81.2% equals 1.12 pounds of water/min.
.9. 85 I 9. 62% equals .9h8 pounds of water/min.
1.12 plus .9le8 equals 2. O68#/min. total water entering
1.38 plus 9.85 equals ll.23<_)#/min.. total feed
2.068/11.23 I 100 [equals 18.4% water in the

entering feed mixture

21

DATA
RUN #1 May 19th
Green reed 28£ # tine 29 minutes
Recycle feed 16 #
Gas tank sent empty during this run. Heat supplied

to drier reduced. Time lost approximately 1. minutes while
changing tank.

RUN'#2
Green i’eed‘ ‘ 1.1.; # tine'32 minutes
Recycle was continued from Run #1

Green feed rate 1.3 [min
Recycle rate 9.85 /min

Product 16% #

Recycle removed at end oi‘ run 13} #

Power 'amps. 7 avg.
velts use
POI. 68
Temperatures .
‘Entering bottom. entering top leaving blewer
1000 - 1300 900 - 1200 180 - 260

Propane used 3} #

Moisture 1
Green feed 81. 2%
Recycle 9 .62%
Product ,7.7z%

Recycle ratio 7.15 # per # green feed

 

‘
o
r .
i p,
u e .I
I e K + y
. -e . e
v ,. .
., .
.
I a
n .. N -
. . .L .I
_ -.
. .
k s
. L
I
v
a
r
\.‘
.
A
e
< .
e
-
.o
I.
x

. 1 .
r .u .
. . . . x.
. I
-~ I,
n‘ e ~
v . n :I
l I n n O .h.
a w I
. 5 ..
J .. .. ;
‘ \ l e
~ ‘ 5
J
l O
. . c .
.
. I
. I
.. .
. O
C
I
A I
.
‘ n
. c , .Ia,
.
.

22

Ne antioxidant was used in runs 1 and 2. Recycle was made

up of old dry hay'which.had been ground in the mill.

RUN #3 May 26th
Green feed 25# time 20 minutes
Recycle 20#
Antioxidant - Publicker # 1
Carrier - soybean 011 plus acetone
moisture _
product ll.x%
recycle 8.6%

RUN #1. May 26th
Green feed 29# time 21 minutes
Recycle l3§ . ‘
Antioxidant - Publicker # 1
Carrier - Propylene glycol
moisture _
product 13%
. recycle 8.6% A f
Runs 3 and L had recycle made up of old dry hay

RUN #5 June 1st . . .
Green feed 89# time 78 minutes
Recycle 15f
Antioxidant - none

 

 

 

 

 

 

. 4‘
‘ . -' ‘ I -1
.
~ 1
, . . . ‘
‘ . ‘ ' ~ -
' ‘ l . A .
.. ,. ‘ - a
‘ ‘ r r
‘ ‘ . ..
V ‘ I
‘ ‘ . .., _ ‘ ‘
I l
a , g. 7“ ~ 4..
‘ V ' '
I l
‘ Q . ‘ I
~' ‘ .1 . h h
‘ .
I ' A - . }
. ,
0
l ' ‘
m '
. . _
k ,
. . , - , .
r. - N A ~ 1 " ‘. .4
I a
.
1
._.

 

23

Samples taken after 50 and 89 #

.Motor overheated after 89# had been run and
stepped at this point.

Entering gas temperatures 900-1000 degrees F

Moisture Prod. l 8.1% 2 7.5%
Reeyol 2 9.5% 3 1h.7%

Propane used 6 i

RUN #6 June 27th

RUN

Green feed 38% # time 1.0 minutes
Recycle 8 g f _ ‘

Antioxidant - 2.5 di-tert-butylhydroquinone

Carrier - Soybean oil plus acetone

Product 95#

Recycle removed 6 f

MOisture Product 7.54%

#7 June 27th . ..

Green feed 58% # time 39 minutes
Recycle 8 #

Antioxidant e p- Isopropoxydiphenylamine_

Carrier - Soybean oil plus acetone

Product 9 #

Recycle removed 6i i .

‘Hsisture in Product 7.5%

Run

Run

Run

2h

#8 June 28th _
Green feed 31# tbme 35 minutes
Recycle 95f

Antiexidant - NH di-scc-butyl-p-phcnylenediamine
Carrier - Soybean oil plus acetone

Product 7#

Recycle removed 9%} .‘

Moisture in.Product 7.02%

#9 June 28th .
Green feed 30# tine 32 minutes
Recycle 9#

Antiexidant _- Publisher #1

Carrier - Soybean oil plus acetone

Product 9!

Recycle removed 8# . . f _
Temperatures or Runs 6, 7. 8.and 9 a ’800 - 1100
Pewer 6-7 amps at A40 velts and.P.P. .65

#10 . . ..

Green feed #35? time 50 minutes
Recycle _ 12§#

Antiexidant - none

Pmm 95‘

Temp. or entering gases 1000 degrees I
Temp. er leaving gases 250 degrees I

n
, r
. w ' ._ ' ‘ r— ‘ ‘
. . » . H u . . . - . . . e
. . '1
. an; .
, ‘ .. e, . - -
.
. A ‘
. u . . - y 0 s
. e
g > ‘ - ‘.~ .
,
~ ‘ I 3
| .
~> , . .
1- < s 1
.
. . 1
~ _. s
e ‘ 9
s
‘ 1
— 4
. l . , _ ‘
e
. e .
_ c.
, . .
.
‘V «
v
, , . .
e
n ' < - ' e .
x 1 .
- .. '1
(I ' s , v -
-. - 1
.
J-
I n
, ,
_ r
' e
——
.a
l
, g o
. . ‘ -
.e . ‘
‘ \ r ‘
v . p .

 

 

Power

Run #11 f
Green feed
Recycle
Antioxidant

‘ Temperature

‘Product
Recycle

25

Amps. A-6 average 5
volts 4A0 ‘
P.F. .60 " 065

90# - time so minutes
w e ' ‘
2.5 di-tert-butylhydrequinone
900 - 1200 entering gases
'250 leaving gases
22# moisture 9.8%
lti' ‘Propane used 6&#

e
‘-
» . _ ~ ..-.
J «1 ‘ "-
’ '
I ' . "u
x - ' .. ,-
e.’
s .
,. -
' n. ' >
_ ..-

 

 

 

26

assesses szehnuHu

wreeoseaeu orHeHn. Kw osuowene Knees. men.
was mesvwe upwaeu ups-K A upweeu noun. wee Hcoap men «Hal. nix :Heuennpun\
new prose as. none. “or .. . . . ma .
N ..r oq.c p ou.p ce.¢ were .mmrc .oeep mo.p ee.e
as. cm.m m oq.w rp.w r~.w .nmou .Omuo .uu.o {‘.
memwewe more w wwrw were rmpm rmwm .Hooo woo.o
. no.» r o~.o uo.m r~.e .mpm. .pooo poo.o poo.
oases ou.q m ow.“ mm.» uc.m .wpos .pumu Hem.» How r
as. mu.p a mo.r no.» we.“ queue .Hoau pout» .
u mean ow” p mm.o we.“ we.» .npuu .Hooq you.» poe.m
ou.q m mm.. uo.e rm. rooms .Howr How.r .
woowove oq.o u wu.e wu.o umro .Huro pomqw mapu ow n
_ mo.e r wwso ow.o as.“ .Hwon .oumw mm.p .
r. wean oq.u w or.“ so my.» .Hemu .omuw mu.w mm.»
oc.o m we.» so u~.o .Homm somwu more _..
wooqowe om.“ u mo. uw. or. rHHHm pommm mm.m a o
oq.m r we.» oo.m ouqm .ownr .oemn me.» u .
m moon 0“.» H oo.e mm. no.u pwmwm ”Hope you H N
ou.o m mm.. up.» ww.w pumum “Hope we». o ,
weowowe oqpm w em.w wr.r w VP puma» ”Huwr kurr Hmm m
om.o : os.‘ em.“ we.o .mceu .osem sso.m .
e macs om.o H 00.0 we.“ wqrq .mmwe rpmmo Humpo Hmu.m
om- s oe.m we.q em.e .msoc .pmro pus.c .
q secs cm.o u no.0 em.r eons .mmpq honor omens pm» n
we.“ r om.r um.« um. .mrps .pnoo w»o.a .
m wean om.e p no.0 em.m um. .mmpa .pmwm Hmm.m on .o
om.m m oo.p wo.m um.o .Nsom .pmur p»e.p r.

 

L.

.e

t.\

:4 IJIIIII .l. I

. .
.\ I,
I.

u
. . .u
A.
0a D
u .
e
_
.1,
.
I
.
l
.

I.
I .
'
a .‘| .
.D
I.
_
f: . U
s
i
., . C
I II .,
n
I
.. C .
e
.
p»

27

was moneys
0 much
we wuoo
wuss:
can
as
bus
new
pH ween

wreaosedou
wwwdeu upsuw
mrw r_uea .29. noun.
omrm w ea.»
em.o p om.c
oo.a H ou.w
om.e N om.c
we. H aqua
wm.m ~ oq.w
worm u wm.o
@040 r oqto
om.m u ww.w

owaHHZN burfiflmHm

aspen»
wuweeu

we:

wq.m
we.s

um.»
mm.m

mm.
“p.m

mw.u
“0.0

wu

acne.
wm.o
so.m

ep.o.
ce.q

mo.u
we.r

uwrw
mm.»

wm.r

gm onuoaoue

mew comp wen «Has
.me0 .Hmmm
.muwu .Hwao
.mwoo .kuu
.meoe .ossm
.Hmou powem
«prom .orow
.Hmuw .omme
.Hmro .ommm
.mqwo .meo

:che

«ems. zuouonupmn\

Humor
pse.e

you.»
woo.m

one .
ope.o
wo.wm

mm.um

wa.0

28

obwoamzm >2>HKWHm >26 nozwwamoz

* on

sea wraps URN was»: caucuses

Us: mg musuwe garnered Koreans Spouomafi Kwouomnmnhm\ weak—hen
Ea S m menu” 22:. 3... $8 mom.
financed Zone Ho.u Howe? Mme.» we
weoHoHe Zone mom Hooto HNH
Emu me u financed wcuwpowou mp us HH.H Hor.m ppm
meowowc meadow: opp w m.o my.» 0Q
reasons . .
one so 1. wuoscos 335on 3 as 3 mm.» 2..“
weowows wuouawesomwwoow m.e no.0 op.u
acne H m financed Zone m.H Hm». mow mm.r
weouowe Zone otu www.r Hrq.
acne mu 0 financed w.“ bwudoadnwsdwwu um.r Hum.m Hum.o qw.m
Sassoon. .
acne mu a wuoasod Haowucwonwn»wueuawsa q.w Hmr.~ Pvt.» qw.m
Buns
acne mm m mucosoa 2.2.npumooaucdwwaus. we.» Hmr.m Hut qw.q
voobawenonpnshse . -
mesa mm o moose: 3355:. 3 «.2. So. were .38
Hans we we swooped Zone once Hpqwo Hwo wo.m
acne we Macaw Zone um.m wo.ou qu
muses - . .
name we wwmoa Zone HH.m mm.mm ou.o mo.H
r opus . ..
acne mo Hp muonson N.“ bundauanwcnwwu o.m Hum.o Huo.o mo.r

anHopspboue

 

 

.
‘I
I e \
.
C . e
_ . _ .
.or . \u a
\ F
C I ~ a
\ o . e
I I V4 , I a! ~y I. ‘ ‘I
. . r, I I . .s.I I .
I O
.
Q
. e. T . e e . I
I 0 v
v I I < w
’ ‘. .I
.
D ‘
. . I...
I v I 0 V
y b -
.
.
. I. . , e I:
, I».
I V J ‘ ‘ I CC .
I r . I.‘
p o'. ‘
e I 0“
. I 1 .. - :u
I I. . use I
n s e
I
I .
. J
I a I I '
I s 1 I y I
.
. .
. I. I , ..
. ‘
.
. .I I q.
.

I .o r. . e .I .
i . .I le .' -f . .1:
.. .J. .. 0.. .
1 0| 'I

6 s. I
.l '
e . . . . O x.
. 4
I II .-
i
a I I I O u.
a — u
. .
e .
.
. ..
I . . I
I ~ 9
I... . e
I. l
o I. o ..
. e . 1 . a
.
. .
I . . o I
e : e
L
I .I O
I
.
e \ e
.

‘v

SUMMARY OF DATA

% er Caretene

RUN FEED RATE retained in
#[nin (green feed) Product
1 1.025 ----
2 1.38 59
3 1.25 ----
a 1.19 ----
5 1.1h 68.A
6 9,96. 72,3
7 09988‘ 71.8
a 6.39 71.7
9 09937 7995
10 0.87 69.5
11 1.125 80.h

Air Dried (A days) 50.1

 

.1

\
J
. s.-
ol 9 Q
a .L.
.x..
‘.J
‘
u
{
I m
a h
,. .s
C

1.
2.
3.

1..

5.

6.

7.

8.

9.

CALCULATIONS

Weight of alfalfa
.- measured
Length of run
measured
Peed rate _ f _
# teed/tine 3 #lm.
leisture

Grams of water sam le x 100 = % water
total :15. 0? sample
Moisture in feed mixture

explained under moisture determination

Power =_ 31 cos 1 [tine] = kilowatt-hrs

H.P. ~= kilowatts/.766
Hourly production en 10% meisture basis

Pewer

min of feed x 60 lqmoisture in een reed
- o s ure n pro uc

he : _, - 7' " , . ..
1.38 x160 ; .2 = 18.1. pounds dried meal/hr.
l-e
H.P. required . '
EI cos 0 / 71.6: 1.1.0 x 6 x ASS/71.6323
Power consumed

11.2.: 71.6 / mm: 2.3 x 71.6 / moo: 1.711. m

 

I hen

 

_ l . I
a s e e
er . A -1
er A II . . ..
l 1‘ I
‘1
a It
'9‘ a l \l
O
. . o .
a
. e e e
J i

1.

2.

3.

1..

5.‘

6.

7.

8.

9.

CALCULATIONS

Weight of alfalfa
; measured
Length of run _
measured
Peed rate 9 _
# teed/tine 3 Wm.
lleisture

Gr$ or water in sample x 100 = % water
ota 9., o samp e
Moisture in feed mixture

explained under moisture determination

Power 3 31' cos 1 page} = kilowatt-hrs

H.P. ‘3 kilowatts] .71.6 ‘

Power

Hourly production en 10% meisture basis

min of reed x 60 . 1-moisture een reed
- o s ure n pro uc

Eze' ‘ I . ‘ ‘ , . '1
1e28 1160 i e2 = 18.1. Donna dr1.d n..1/hre
l-e
H.P. required
EI cos 0 / 71.6= 1.1.0 x 6 x .65/71.6=
Pewer consumed

11.2. x 71.6 / loco: 2.3 x 71.6 / moo: 1. 711. m

.wIl

. .-

(A

 

 

.u
I
m
r ._
v
_
...
,
u
e .
fl fr
I. a
.4
a .
o n
. p
is I .
A A .
-no a
.,
a. P .
. .
. .
. r . I
.\ .
_
.-
. _
.1
. _
x.
I a
\ .
.
.
a
II.
I -
s.
1‘

e
"i
D.I
.
,..1
1.).
r
‘
.~
.. .
u -

 

 

., .(

 

 

vs
.I

.6- ..

III—

31

10. Fuel consumption

Fuel rate/Product rate =‘ffue1/#product
Calculations in the analysis for Carotene '

Column (Sample)
measured weight
Column (filter 21.3 I: 396)
_ read from meter on colorimeter
Column (flask number) _
number on the sample flask
Column (Corr.)

chlorephyll correction taken from calibration
tables for the reading from filters 21.3 a. 396

Column (Chlere. Corr.) 7
Column tilt“? = carotene reading corrected
. . _ 09““ 91'1‘ f - for chlorophyll
Colman (Mg carotene/100ml)

taken from calibration charts comparing colori-
meter readings with concentration of carotene

Column (Mg carotene/gm)

Column e rotene‘ O a concentration of
sample weight in grams . carotene

Column (Micro gin/gm) f _ ,
. Column (Mg carotene/gm) x 1000 3 micro gms/gm
Column Avg.

Average concentration of two samples of the same
product (weights are on wet basis)

'I

0 xx“

b

 

 

 

Uh ‘TO

I
. e n
a. a
.e .
a
. .r
.0: 4
;.
‘w
, v
. r .
. a
I t
v.
. fl.
. .
.‘ I
1 .‘
l
a
.
a .
. _
\I
I, Q
. .
. .
. a.
.
q
n
.e
file
J ...J

 

e a
3 .a .
e I“ 1 n .
N t
’
w 1..
. .
. .. . H
. n .
. a
. ‘n ‘
r .
J . .
.
U» n
.
0 , e
.V
.. u
v
u o
. .
o
. .
c .
.
.
. .
.
.

‘d

[In 1‘ (( hr..l. I ‘1 I Ii] J! ‘II‘MI .il {5‘ ill...
.
. . ,0.
I «a .
[or u
. r
. u e
n
t I
. ,f
a
a ‘
\A
u
.
. .
o
. I
» ea}. 2.
. .
.
.
J
. _ .
.
e .
. . _
.|

Concentration on dry basis

Celunn (Avg)/lqmoisture content or sample 3
concentration of carotene per gm. on dry basis

32

 

 

. .1! if}: Fill. clef"-..

33

DISCUSSION

RUNS l and 2

Runs 1 and 2 were run at maximum capacity. Highest
.temperature’was maintained and feed rate highest which would
not overload.motor and mill. It was noticed that the limit-
ing factor of overload on mill also controlled the temperature
which it was possible to use. ‘When the temperature of the
entering gases went above 1300 it was not possible to feed
enough green alfalfa to the mill to keep the temperature low
'enough to prevent igniting the dry alfalfa. If more green
alfalfa was fed. the mill became clogged and more of the .
gases were pulled in through underneath the mill, increasing
the temperature in the elutriator to a point where the dry
meal was ignited. If more recycle had been fed with the green
feed, the motor would have become overloaded. At high tamp-
'eratures the bearings became overheated so that the lubricant
'floumd away from.the bearings. For long continuous runs these

bearings should be cooled in some manner.

RUNS 3 and h .

‘ Old dry hay was used as recycle material. The short-
ness of the run and large amount of recycle were responsible
for the low carotene content as considerable amount of the
old hay recycle passed over into the product. The purpose

of these runs was to test the effect of different carriers on

‘.
.a
A ‘ I A
l
. A. x.
v.
. .\.
s . . ,
... A

J
l
h s
a
. .. .
4
I .
:
a p
n a
4 _
. . . . .
D
L .
1.
. .
a
. m .
(I.
.. ...
l
. .
J
.
. .
o I.
.
.
X»
e
I
I .
. v _
. .A
p I

 

V \a

\_-ij

3h

the retention of carotene while still using the same anti-
oxidant. From the results, it appears that soybean oil plus
acetone was better as a carrier than propylene glycol. As;
a result of this run, soybean oil plus acetone was used for
all other antioxidant runs.

RUN 5 . ,

In this run 89} of green food was used. Samples were
taken after 50 and 89 pounds of green alfalfa had been fed
to mill.‘ The purpose of this run was to obtain a run long
enough so that the recycle material would not enter into the
carotene analysis. It was found that the samples after 50#
and 89} agreed very closely, so it was reasonable to conclude
that the recycle introduced at the beginning of the run had
no more effect on the carotene content in the product after

50} of green feed had been introduced.

RUNS 6 - 9 _ ‘

These runs were made eonsiderably later in the season
than the first five runs. As a result, the alfalfa was quite
mature and the stalks were heavy; making up a greater portion
of the weight than earlier in the season. It was found that
the carotenein the green alfalfa was much lower than at the
earlier date; therefore it is difficult to compare the care-
teno content with the early runs. Comparison was based on
the i of total carotene in the green alfalfa which was
retained after drying.

 

 

&. . .
_
II ‘1."
l
.
a. k
, v
a n
x t .
w n i v
, .
- uK N
at
C H I 1
¢
..~
.. . I
.
L
. u
a... t.
i
v.
4 .7
J
c
. ....
- c.¢ ‘
.
. J
o
.4 ‘ .
I
h
, . A
i u
.
‘
.
‘ .
. _
a

 

. 4 v- . .
I
. .
.e
e I
e
.
.~
.3 .r r
\ .
‘l
. . .
.
l I
a; .
a _
e . .
4. .
.
l .
. . ‘
. Po
. r
a .
. v , e
. .,

Jill l‘xi Ila" l‘l

35

It was noted that antioxidants increased the % of
carotene retained in runs 6to 9. There was not a great ,
deal of difference in the effect ofthe various antioxidants;
2,5 diotert-butylhydroquinene appeared to be the best. Hows
ever, it is suggested that the equipment be improved to permit
longer continuous runs, and that the tests be carried out ’

using long runs.

RUN 10 ‘

This run was made as a control for runs 6 to 9.
Since the runs using antioxidants had been run later when
the carotene content of the green feed was low, a new basis
for comparison was needed. However, based on the % of care-

tene retained, runs 10 and 5 agreed quite well.

RUN ll ‘ |

This was a long run of 90% using 2,5 di-tert-butyl-
hydrequinone for the antioxidant. It was found that 80% of
the carotene was retained in the sample taken at the end of
this run. ‘ .

g The lower feed rate in the later runs was used in
order not to overload the mill and cause stoppage during the
runs. The temperature was lowered in order not to overheat
the hearings on the mill. . ' .

‘Whon the amount of recycle was small, as in runs 6

and 7, the texture of the product was different than when

 

.
r
”I.
u
0 I
x 7'
o
e .‘
.
.l
.. F.
t u
.
u .f.
r.
e
e
.
f
.
a .,
u. .
v
o.
I.

:3.

 

fili..:’

a .9 earl}:

.1

it

A.“

4.1.9..le

1?.

J.

‘1

7'

5:!

 

36

more recycle was used. The ratio of recycle to green feed
was small, which means that the moisture content of the
mixture fed to the mill was greater. The product in this
case appeared to be more stringy and shredded. It is likely
that the hammer mill had more of a tearing action on the
wetter material. Another factor which may have entered into
this was the tough woody fiberous condition of the stems of

the alfalfa, since it was cut when it was very mature.

 

r
. w e.
I . a . I.
. .y
a d
. ..
.
o
v
i
A .
.
-
s
n .el
\. .1)
z
. 'a
u .
a
u .
rs . i
.
U
I
a
x
.

 

 

 

37

CONCLUSION

The maximum capacity of themill appeared to be
about l.k.#[minute of green alfalfa containing 81% moisture.
On an hourly basis this would be 8hf/hr of green feed, which
would result in an hourly production of l7.75# of dried.moal
containing 10% moisture. _

Fuel consumption at the maximum capacity was .073h
#[minute or 0.2L8# of fuel/# of product containing 10%
moisture. 7 ‘

Power required for mill and blower was é.l kwh. This
is equivalent to .1183 RIB/i of product.' ,

The limiting factor to capacity when sufficient recycle
was used was the power available. The motor would become
over-heated and stop. ‘When less recycle was used, the limit-
ing factor was the.mill.g The mill would not handle the wet
material and became clogged. ’ _

Antioxidants present in the alfalfa fed to the mill
improved the carotene content in the dried product. '2,5 di-
tertebutylhydrequinono provided the best protection for
retaining carotene.

The rate of recycle at maximum capacitytwas 7} of recycle
to l# of green feed. This is equivalent to a.moisture content in the
entering feed mixture of 18.6% . A ratio of 6 : 1 would result in

a moisture content of about 223, which could still be handled by the

mill easily without clogging the screen.

 

 

 

Va

l.
2.

3.

l...

38

BIBLIOGRAPHY

Thompson, C. Ray - Industrial Engineering Chemistry
May 1950, page 923

Kennett,‘Wilbur - Thesis 1950, Michigan State College

Tauber, Henry - Journal of American Chemical Society
l9hl, page 2251

Strain,.H. H. - Journal of American Chemical Society
1941. page 35b2

Silker, R. E.,~W. G. Schrenck, H. H. King, Industrial
and Engineering Chemistry
l9hl, page 831

 

.
U I O
J
u on
c . g o
.
.. s.
, .
1..
' ~I '
. 0 I
.
q
_ e O
.I
n I .
x
A I
r \ {nth . ...
.
- ‘ . r
v r. . V
. o i
.I
. at 4 I. I
a .v <.. (A
v o
. . a.
. . ..
. ...
.d
u . 1. . c
I. J
. . . . .
.
.
a ,T n; . .
. P a
‘ a
n e
I
I
x x
. . .
.
u. I: . I. I!

 

,‘
.I'I

 

 

It

ir
.75?!

 

| . I I. y
i ' I!" t- '-‘l INK-I—

AAAAAAAAAAAAAAAAAAAA

MM \\\\\\fi\\'\j§\\j\$\\ifiufimmm

93

\muwgmx