Thermophilic anaerobic digestion of Lurgi coal gasification wastewater in a UASB reactor.
Lurgi coal gasification wastewater (LCGW) is a refractory wastewater, whose anaerobic treatment has been a severe problem due to its toxicity and poor biodegradability. Using a mesophilic (35±2°C) reactor as a control, thermophilic anaerobic digestion (55±2°C) of LCGW was investigated in a UASB reactor. After 120 days of operation, the removal of COD and total phenols by the thermophilic reactor could reach 50-55% and 50-60% respectively, at an organic loading rate of 2.5 kg COD/(m(3) d) and HRT of 24 h; the corresponding efficiencies were both only 20-30% in the mesophilic reactor. After thermophilic digestion, the wastewater concentrations of the aerobic effluent COD could reach below 200 mg/L compared with around 294 mg/L if mesophilic digestion was done and around 375 mg/L if sole aerobic pretreatment was done. The results suggested that thermophilic anaerobic digestion improved significantly both anaerobic and aerobic biodegradation of LCGW.
State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, China.
Wei
W
Wang
Wencheng
W
Ma
Hongjun
H
Han
Huiqiang
H
Li
Min
M
Yuan
D001421:Bacteria, Anaerobic / Q000378:metabolism*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology*; D003031:Coal / Q000382:microbiology*; D007220:Industrial Waste / Q000517:prevention & control*; D014873:Water Pollutants / Q000302:isolation & purification / Q000378:metabolism*; D018508:Water Purification / Q000379:methods*
D003031:Coal; D007220:Industrial Waste; D014873:Water Pollutants