Treatment of Coking Wastewater Using the Micro-electrolysis-SBR Activated Sludge Process

Tests has been carried out on treating coking wastewater using the micro-electrolysis-SBR activated sludge process. The results show that the micro-electrolysis technology not only removes COD, phenol, cyanide, sulfide in the wastewater, but also improves its biodegradability (BOD5/CODcr) from 0.28 to 0.54. With the micro-electrolysis technology, the removal rate of COD, phenol, cyanide, sulfide is up to 70%, 77%, 68%, 71% respectively. By orthogonal test, the best parameters of micro-electrolysis pre-treatment of coking wastewater are: influent COD2200~2400 mg/L, influent pH 3.0~3.2, HRT 55~65 min, volume ratio of Fe/C=1:1.5. Using the micro-electrolysis-SBR bio-treatment technology the effluent water can meet Grade I requirement of the National Discharge Standard (GB13456-1992) for discharging industrial wastewater.