Treatment of ABS Resin Wastewater with Integrated Cycling Bioreactor

An integrated cycling bioreactor with gas lift and microporrus aeration was used for the treatment of ABS resin wastewater. When the hydraulic retention time of the reactor was 24 h and the influent COD_Cr was 800-1 000 mg/L, the effluent COD_Cr was less than 80 mg/L. COD_Cr removal efficiency was higher than 88% and organic nitrogen removal efficiency higher than 99% by the single reactor. When the influent alkalinity was 300-450 mg/L (as CaCO₃), the pH of the mixed liquid in the reactor could remain at 6.7-7.5, and the effluent NH₃-N was less than 5 mg/L. The treatment load of the reactor was significantly higher than that of the traditional process. GC-MS and three-dimensional fluorescence spectrum analyses indicated that organic nitrile and aromatic organics could be efficiently removed from ABS resin wastewater.