Anaerobic Biochemical Treatment of Wastewater Containing Highly Concentrated Organic Cyanogen

Abstract

The first and second stage of chilled wastewater in acrylic fibersitrile process and wastewater in acrylic fibers process are biodegraded under anaerobic conditions. Toxicity of acrylonitrile, acetonitrile, polymers, and cyanide in the wastewaters to the production of methane has been studied. Results suggest that the first and second stage chilled wastewaters from acrylonitrile process and wastewater from acrylic fibers process cannot be biodegraded well. COD_BD of the first and second stage chilled wastewaters from acrylonitrile process is 36.3 and 45.8. COD_BD of the wastewater from acrylic fibers process is 53.0. Acetonitrile, acrylonitrile, polymers, and cyanide are toxic to anaerobic bacteria in the highly concentrated organic cyanogens containing wastewater, inhibiting the methane-producing activity. Half inhibition concentration (50% IC) to anaerobic methane-producing activity is 1,300, 320, 85, and 50 mg/L for polymers, acetonitrile, acrylonitrile, and cyanide, respectively. Acrylonitrile is a metabolizing and physiological toxin, acetonitrile and polymers a metabolizing toxin, and cyanide a physiological and sterilizing toxin.

Keywords:

• 50% inhibition concentration
• anaerobic biodegradation ability
• organic cyanogens containing wastewater
• type of toxin