Start-up of a thermophilic methanol-fed UASB reactor: change in sludge characteristics.
Experiments were performed to study the change in sludge characteristics and sludge granulation during the start-up of a thermophilic methanol-fed upflow anaerobic sludge bed (UASB) reactor. The laboratory scale reactor, was inoculated with thermophilic granular sludge and operated at 55 degrees C over 130 days at organic loading rates (OLR) varying from 2.7 to 47 gCOD.L(-1).d(-1). Physical characterisation was performed for both the seed and the cultivated sludge. Results demonstrated that a good quality, well settleable granular sludge was cultivated and retained in the reactor, allowing an OLR of 47 gCOD.L.d(-1) with 93% of methanol removal, where 79% was converted into methane. Using a community analysis of the cultivated consortia, high numbers of rod-shaped hydrogenotrophic methanogens were enumerated. Biomass washout coincided with a high specific gas load, but was not detrimental to the system in the conditions tested.
Sub-Department of Environmental Technology, Wageningen University, The Netherlands.
P L
PL
Paulo
B
B
Jiang
K
K
Roest
J B
JB
van Lier
G
G
Lettinga
D001421:Bacteria, Anaerobic / Q000502:physiology*; D019149:Bioreactors; D019605:Euryarchaeota / Q000502:physiology*; D010316:Particle Size; D012722:Sewage / Q000382:microbiology; D014865:Waste Disposal, Fluid / Q000379:methods*
D012722:Sewage