Optimizing feeding composition and carbon-nitrogen ratios for improved methane yield during anaerobic co-digestion of dairy, chicken manure and wheat straw.
This study investigated the possibilities of improving methane yield from anaerobic digestion of multi-component substrates, using a mixture of dairy manure (DM), chicken manure (CM) and wheat straw (WS), based on optimized feeding composition and the C/N ratio. Co-digestion of DM, CM and WS performed better in methane potential than individual digestion. A larger synergetic effect in co-digestion of DM, CM and WS was found than in mixtures of single manures with WS. As the C/N ratio increased, methane potential initially increased and then declined. C/N ratios of 25:1 and 30:1 had better digestion performance with stable pH and low concentrations of total ammonium nitrogen and free NH(3). Maximum methane potential was achieved with DM/CM of 40.3:59.7 and a C/N ratio of 27.2:1 after optimization using response surface methodology. The results suggested that better performance of anaerobic co-digestion can be fulfilled by optimizing feeding composition and the C/N ratio.
College of Agriculture, Northwest A&F University, Yangling, Shaanxi 712100, China.
Xiaojiao
X
Wang
Gaihe
G
Yang
Yongzhong
Y
Feng
Guangxin
G
Ren
Xinhui
X
Han
D000693:Anaerobiosis; D000818:Animals; D056804:Biofuels / Q000032:analysis; D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000032:analysis*; D002645:Chickens; D003612:Dairying; D006863:Hydrogen-Ion Concentration; D008372:Manure / Q000032:analysis*; D008697:Methane / Q000138:chemical synthesis*; D009584:Nitrogen / Q000032:analysis*; D014908:Triticum / Q000737:chemistry*; D014835:Volatilization; D014866:Waste Products / Q000032:analysis*
D056804:Biofuels; D008372:Manure; D014866:Waste Products; D002244:Carbon; D009584:Nitrogen; D008697:Methane