Biogas production from anaerobic co-digestion of cow manure and leaves of Miscanthus x giganteus

摘要

Lately, anaerobic digestion process has gained particular attention due to the environmentalbenefits on reducing greenhouse gases emissions and biogas generation, which is a promising source ofrenewable energy. The manure from livestock industry, mixed with energy plants or with agriculturalresidues, can be processed in an environmentally friendly manner through the process of anaerobicdigestion, in order to obtain biogas for electrical or thermal energy production, and to use the digestateas soil fertilizer. In this paper was studied the production of biogas generated by the process ofanaerobic digestion of cow manure mixed with Miscanthus x giganteus biomass, a C4 energy plant.Also, it has been characterized the substrate tested in various stages of anaerobic digestion. Therecorded parameters were: pH, total soluble solids, content of soluble proteins and sugar content. Theresults showed that the maximum yield of biogas, after 15 days of anaerobic digestion, was of 0.420Nm3/kg dry matter, and the biogas started to form on the second day of incubation. During theanaerobic digestion, it was observed that the values of TSS and pH were slightly decreasing due to thegrowth and multiplication of bacterial cell, the consumption of substrate and the accumulation ofmetabolites. Reducing sugars and soluble proteins were found in small concentrations at the beginningof anaerobic digestion process and at its end were undetectable.