Tofu wastewater treatment using contact glow discharge electrolysis method and air injection

Abstract

Tofu wastewater is one of the most dangerous source of environmental pollutants. It is known that the COD of tofu wastewater can reach 8000 mg/L. Contact Glow Discharge Electrolysis (CGDE) method is an effective method in degrading complex pollutants contained in tofu wastewater, due to its ability to produce large quantities of OH radicals. This study aims to test the ability of the CGDE method in degrading the tofu wastewater by the addition air injection. In this method, several variations were made to determine the optimal airflow rate and initial concentration of tofu wastewater. Tofu wastewater degradation reached 73% for 120 minutes, with the final value of COD is 425 mg/L and BOD is 447 mg/L. Maximum conditions are obtained by using airflow rate 2.5 lpm, temperature 50°C, and initial concentration of tofu wastewater is 2000 ppm. The addition of air injection with airflowrate 2.5 lpm is able to reduce energy consumption by 37%. The results show that CGDE with air injection has the potential to degrade pollution parameter in tofu wastewater.