Feasibility Study for Anaerobic Digestion of Agricultural Crop Residues. 1980 Update. Final Report

摘要

The objective of this study was to provide cost estimates for the digestion of corn stover to fuel gas. Engineering economic analyses were performed for digestion of corn stover for small farm cooperative and industrial scales. The small farm scale processed the residue from an average size U.S. farm (400 acres), and the other sizes were two and three orders of magnitude greater. Recent experimental results obtained by Gaddy and by McCarty for yield and kinetics of corn stover digestion were used in the analysis. The results of the analyses indicate that production of fuel gas from corn stover is, at least, marginally economically feasible for both continuous and batch digestion processes. A sensitivity analysis was performed to assess which parameters significantly affect system economics. It was found that a credit for digester effluent would yield economically feasible process. Recommendations arising from this study include continued development of a batch hole-in-the-ground controlled landfill digestion of corn stover and investigations into the effect of shorter retention time continuous digestion. The digester effluent should also be evaluated to determine its use as an animal feed or fertilizer. (ERA citation 06:021730)