Advanced oxidation treatment of composting leachate of food solid waste by ozone-hydrogen peroxide

Abstract

The research was conducted to investigate the efficiency and possibilities of advanced oxidation process based on ozone-hydrogen peroxide. The process was used as a post-treatment step of composting leachate utilisation. The leachate samples were collected from a typical composting plant with the aerobic biological treatment system. The samples were conditioned in a "ozone reactor" without dilution. The effectiveness of the treatment process was measured by pH values (4.0-7.0), H 2 O 2 concentrations (0.5-4.0 g·dm -3 ), ozone doses (0.5-1.5 g·h -1 ) and reaction times (0-10 min). The highest removal efficiencies achieved were 85% and 92% for chemical oxygen demand (COD) and biochemical oxygen demand (BOD 5 ), respectively. The optimum process parameters occurred at pH 5.0, 2.0 g·dm -3 concentration of H 2 O 2 , and 0.75 g·h -1 of ozone dose. The optimal reaction time was 3 min. The O 3 /H 2 O 2 advanced oxidation process was found to oxidize COD and BOD 5 of the composting leachate. The oxidation reaction can be used as a feasible technique for composting leachate treatment.