Accumulation of non-merchantable wood and low-value forest biomass risks forest health through pest infestation and diseases. Biochar has been proposed to mitigate the economic and environmental challenges involved with collecting, transporting, and handling unutilized forest biomass. Biochar is a carbon-rich product, produced through the thermal decomposition of biomass in the absence of oxygen. Since Michigan currently does not have any commercial biochar production facilities, there is a gap in information regarding the biochar market (potential supply and demand of biochar) and its potential use as a soil amendment in agriculture. We investigated if biochar can be produced from forest biomass and utilized for soil amendment when procurement is done through stationary and portable pyrolytic units. The first part of the study assessed the economic feasibility of biochar production in Michigan by optimizing transportation costs involved in determining the potential biochar demand and supply when 10 tons/acre of biochar is applied to cropland over a 30-year rotation. The study's second phase conducted a cradle-to-grave life cycle assessment (LCA) to quantify the environmental impacts of biochar production based on different production technologies. For baseline (delivered wood price of $23.25/green ton biomass or $25.54/green tonne biomass), to fulfill the potential biochar demand in the upper peninsula (UP), 132 portable units were required while it was only one stationary unit. For the lower peninsula (LP), a higher number of units are required for both these approaches due to having more cropland in the land cover; the figures were 2 and 596 for stationary and portable units, respectively. Portable units can procure more biomass at the same optimized transportation cost but are only able to fulfill 57% of the potential biochar demand. In comparison, stationary units can produce a surplus of 15%. Stationary units had the potential to reduce GWP by 14.78 tonne CO2e/per state of Michigan while portable units can reduce GWP by 14.37 tonne CO2e/per state of Michigan for portable units. The amount of carbon sequestered due to applying biochar as a soil amendment is 2.445 tonne CO2e/ tonne biochar produced for both these systems, assuming that 86% of the carbon in biochar will remain in the soil. This research has bridged the knowledge gap regarding biochar production and utilization from economic and environmental feasibility perspectives, leading toward building a circular economy in Michigan.
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