A two-stage system coupling hydrolytic acidification with algal microcosms for treatment of wastewater from the manufacture of acrylonitrile butadiene styrene (ABS) resin.

OBJECTIVES: To demonstrate the effectiveness of a novel two-stage system coupling hydrolytic acidification with algal microcosms for the treatment of acrylonitrile butadiene styrene (ABS) resin-manufacturing wastewater.

RESULTS: After hydrolytic acidification, the BOD5 /COD ratio increased from 0.22 to 0.56, showing improved biodegradability of the wastewater. Coupled with hydrolytic acidification, the algal microcosms showed excellent capability of in-depth removal of COD, NH3 -N and phosphorus with removal rates 83, 100, and 89%, respectively, and aromatic pollutants, including benzene, were almost completely removed. The biomass concentration of Chlorella sp. increased from 5 × 106 to 2.1 × 107 cells/ml after wastewater treatment.

CONCLUSIONS: This two-stage coupling system achieved deep cleaning of the benzene-containing petrochemical wastewater while producing greater algae biomass resources at low cost.