Methane production from the soluble fraction of distillers' dried grains with solubles in anaerobic sequencing batch reactors.
Methane production from the soluble fraction of distillers' dried grains with solubles, a co-product of ethanol production, was studied in 2-L anaerobic sequencing batch reactors (ASBRs) under 10 different operating conditions. Methane production and chemical oxygen demand (COD) removal were quantified for a wide range of operating parameters. Chemical oxygen demand removals of 64 to 95% were achieved at organic loading rates ranging from 1.5 to 22.2 g COD/L x d, solids retention times from 8 to 40 days, and food-to-microorganism ratios ranging from 0.4 to 1.9 g COD/g volatile suspended solids (VSS) x d. Biogas methane content varied from 61 to 74%, with 0.29 L CH4 produced/g COD removed. Roughly 56% of the influent COD and 84% of the COD removed in the ASBRs was converted to methane. Microbial yield (Y) and decay (b) constants were determined to be Y = 0.126 g VSS/g COD removed and b = 0.032 day(-1), respectively. Methane produced from co-products can reduce the costs and fossil-fuel consumption of ethanol manufacture.
Cassidy
D P
DP
Department of Geosciences, Western Michigan University, Kalamazoo, Michigan 49008, USA. daniel.cassidy@wmich.edu
Hirl
P J
PJ
Belia
E
E
D000693:Anaerobiosis; D019149:Bioreactors; D008697:Methane / Q000096:biosynthesis*; D012995:Solubility
D008697:Methane