COMBINATION OF PHOTOCATALITIC AND BIOLOGICAL PROCESSES AS AN INTEGRATED SYSTEM FOR TREATMENT AND RECOVERY OF INDUSTRIAL WASTEWATER CONTAINING PESTICIDES

The combination of chemical oxidation with biological water treatment processes is a promising technique to reduce recalcitrant wastewater loads. As a case study, the treatment of wastewater coming from the Pesticides and Chemical Company known with «HELB», located at New Dammata in the north of Egypt was studied, which was characterized as very biorecalcitrant. Photo-Fenton process was explored as photochemical pre-treatment to improve the biodegradability of such wastewater coming from the pesticides industry. The key to the efficiency of such a system is a better understanding of the mechanisms involved during the degradation processes. Wastewater treatment was carried out including a series of bench scale experiments, to identify optimum operating conditions for the treatment of pesticides contained in wastewater at the end of the pipe effluent. The effect of operating parameters as: pH, irradiation time and initial concentrations of both H2O2 and Fe2+ on the photomineralization processes have been studied and the optimal conditions were found.