On the design and operation of solar photo-Fenton open reactors for the removal of contaminants of emerging concern from WWTP effluents at neutral pH

Abstract

This work presents for the first time a tool for the design of continuous raceway pond reactors to remove contaminants of emerging concern (CECs) from WWTP secondary effluents by solar photo-Fenton process at neutral pH. The effects of the hydraulic residence time (HRT) and the liquid depth on the treatment capacity were studied, the availability of solar UV radiation being the main environmental variable. Treatment capacities as high as 1800 and 9000 L m^2/d were estimated for 70% CEC removal in winter and summer, respectively. To this aim, the performance of a kinetic model of the photo-Fenton process developed with Fe3+-EDDS was up- dated to predict CEC removal in effluents collected from different WWTPs. To reach a goal of CEC elimination, the treatment capacity can be maximized as a function of HRT and liquid depth, and consequently the reactor surface area is calculated to treat a given flow rate.