Anaerobic-anoxic-aerobic sequential degradation of synthetic wastewaters.
This study was conducted in a continuous three-stage system of anaerobic (R1)--anoxic (R2)--aerobic (R3) reactors with synthetic wastewater containing phenol (1000 mg/L), chemical oxygen demand (COD) (3000 mg/L), CN- (30 mg/L), SCN- (400 mg/L), and NH4+-N (600 mg/L) as principal pollutants and well-acclimated heterogeneous microbial cultures. The final effluent was partially returned to R2 with a recycle ratio of 1. Anaerobic stage served to detoxify the feed by removing up to 80% of cyanide. Complete SCN- removal and denitrification could be achieved in the anoxic stage by utilizing phenol as an internal source of carbon. Nitrification efficiency of 93% was obtained in the aerobic reactor. The results demonstrated that the three-stage system can give the desired final treated effluent quality (0 mg/L of phenol, 0.2 mg/L of CN-, 210 mg/L of COD, and 20 mg/L of NH4+-N) and that the NO3(-)-N concentration can be lowered by a higher recycle ratio.
Chakraborty
Saswati
S
Centre for Environmental Science and Engineering, Indian Institute of Technology, Bombay.
Veeramani
H
H
D001420:Bacteria, Aerobic / Q000378:metabolism*; D001421:Bacteria, Anaerobic / Q000378:metabolism*; D019149:Bioreactors; D007700:Kinetics; D010100:Oxygen / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
D014874:Water Pollutants, Chemical; D010100:Oxygen