Abstract:
A lab-scale anaerobic/anoxic/zeolite biofilter - membrane bioreactor (A
1/A
2/ZB-MBR) was developed and its performance in coking wastewater treatment was investigated. The operation parameters were optimized. The results indicated that the zeolite could regulate the concentration of ammonia effectively. The best performance was obtained at HRT 73 h, reflux ratio 2:1, DO 4-6 mg/L in ZB-MBR. Under the optimal influent conditions of COD
Cr (1 673±227) mg/L, NH
3-N (125.0±27.4) mg/L, TN (280.5±57.6) mg/L, the effluent COD
Cr, NH
3-N and TN were (145±27) mg/L, (5.6±4.1) mg/L, and (91.4±33.8) mg/L, respectively, and the performance remained stable over 280 d operation.