Improved Dye Wastewater Treatment in an Integrated System Based on Bio‐Electrochemical System and Bio‐Contact Oxidation Process

ABSTRACT In this work, the feasibility of dye wastewater treatment was evaluated with an integrated system (IS) of bio‐electrochemical system (BES), bio‐contact oxidation (BCO), denitrification tank, and sand filter systems. The effects of low carbon to nitrogen ratio (C/N), current intensity, and methylene blue (MB) concentration on the reactor performance were investigated. The results demonstrated that the optimal operating conditions were an applied C/N with chemical oxygen demand (COD) of 500 mg/L, current of 20 mA and MB concentration of 25 mg/L at the BES. Under such conditions, the removal rate of the COD, MB, and total nitrogen (TIN) was approximately 94.6%, 94.8%, and 73.3%, respectively. BES played a chief part in pollutants removal and others further did contribution to nitrogen removal. It indicated that IS might be an effective strategy for improving treatment dye wastewater.