Kinetics and thermodynamics of biodiesel wastewater treatment by using ozonation process

Abstract

Biodiesel wastewaters contain high amounts of oil, methanol, soap and glycerin. These wastewaters pollutant concentrations as chemical oxygen demand (COD), total organic carbon (TOC), glycerin and Me0H are fluctuating in the ranges of 250,000-450,000 mg/L, 54,000-110,000 mg/L, 800-1,500 mg/L, and 6,000-15,000 mg/L, respectively. Biodiesel wastewaters lead to blockage of oil drainage systems and reduction of biological activity in biological treatment systems. The purpose of this study was to treat wastewater by ozonation after the electrocoagulation process as pre-treatment. In the ozonation process, the initial wastewater pH value was 13.9, ozone dose was 1.5g/L h, reaction time was 7 h and reaction temperature was 45 C. As a result of 7 h of ozonation, 98.64% of COD, 97.48% of TOC and 99.37% of Me0H removal efficiencies achieved. With these results, biodiesel waste water can be discharge to into the receiving environment according to standards.