title: Biogas production by co-digestion of goat manure with three crop residues.
abstract: Goat manure (GM) is an excellent raw material for anaerobic digestion because of its high total nitrogen content and fermentation stability. Several comparative assays were conducted on the anaerobic co-digestion of GM with three crop residues (CRs), namely, wheat straw (WS), corn stalks (CS) and rice straw (RS), under different mixing ratios. All digesters were implemented simultaneously under mesophilic temperature at 35±1 °C with a total solid concentration of 8%. Result showed that the combination of GM with CS or RS significantly improved biogas production at all carbon-to-nitrogen (C/N) ratios. GM/CS (30:70), GM/CS (70:30), GM/RS (30:70) and GM/RS (50:50) produced the highest biogas yields from different co-substrates (14840, 16023, 15608 and 15698 mL, respectively) after 55 d of fermentation. Biogas yields of GM/WS 30:70 (C/N 35.61), GM/CS 70:30 (C/N 21.19) and GM/RS 50:50 (C/N 26.23) were 1.62, 2.11 and 1.83 times higher than that of CRs, respectively. These values were determined to be the optimal C/N ratios for co-digestion. However, compared with treatments of GM/CS and GM/RS treatments, biogas generated from GM/WS was only slightly higher than the single digestion of GM or WS. This result was caused by the high total carbon content (35.83%) and lignin content (24.34%) in WS, which inhibited biodegradation.
authors.affiliation: College of Forestry and the Research Center of Recycle Agricultural Engineering and Technology of Shaanxi Province, Northwest A&F University, Yangling, Shaanxi, People's Republic of China.
authors.forename: Tong
authors.initials: T
authors.lastname: Zhang
authors.forename: Linlin
authors.initials: L
authors.lastname: Liu
authors.forename: Zilin
authors.initials: Z
authors.lastname: Song
authors.forename: Guangxin
authors.initials: G
authors.lastname: Ren
authors.forename: Yongzhong
authors.initials: Y
authors.lastname: Feng
authors.forename: Xinhui
authors.initials: X
authors.lastname: Han
authors.forename: Gaihe
authors.initials: G
authors.lastname: Yang
mesh_terms: D000693:Anaerobiosis; D000818:Animals; D056804:Biofuels / Q000382:microbiology*; D002244:Carbon / Q000378:metabolism; D018556:Crops, Agricultural / Q000378:metabolism*; D005232:Fatty Acids, Volatile / Q000378:metabolism; D006041:Goats; D008372:Manure / Q000382:microbiology*; D009584:Nitrogen / Q000378:metabolism
chemical_list: D056804:Biofuels; D005232:Fatty Acids, Volatile; D008372:Manure; D002244:Carbon; D009584:Nitrogen