Uasb Treatment Of Wastewater With Vfa And Alcohol Generated During Hydrogen Fermentation Of Food Waste.pdf

Process Biochemistry 40 (2005) 2897–2905
ate/procbio
UASB treatment of wastewater with VFA and alcohol
generated during hydrogen fermentation of food waste
Sun-Kee Han *, Sang-Hyoun Kim, Hang-Sik Shin
Department of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology,
373-1 Guseong-dong, Yuseong-gu, Daejeon 305-701, South Korea
Received 4 May 2004; received in revised form 17 October 2004; accepted 8 January 2005
Abstract
The performance of an upflow anaerobic sludge blanket (UASB) reactor treating wastewater with volatile fatty acids (VFA) and alcohol
generated during hydrogen fermentation of food waste was investigated. The chemical oxygen demand (COD) removal efficiency exceeded
96% up to the loading rates of g COD/L d, corresponding to a food/anism ratio of g COD/g VSS d. The methane
production rate increased to L/L d. Each gram of granule in the reactor had a daily maximum capacity of converting g of COD to
methane at the specific substrate utilization rate of g COD/g VSS d. Of all the COD removed, 93% was converted to methane and the
remaining presumably to biomass with a yield of g VSS/g COD. At loading rates over g COD/L d, the COD removal efficiency
deteriorated due to sludge flotation and washout in the reactor, which resulted from short hydraulic retention time (HRT) of less than