The performance of fluidized bed solar photo Fenton oxidation in the removal of COD from hospital wastewaters

摘要

In this study, fluidized bed solar photo Fenton process was adopted for the treatment of hospital wastewater with an objective of improving the biodegradability and reducing the chemical oxygen demand (COD) of wastewater. The optimal conditions were observed at pH 3, Fe2+ dosage of 5mM, H2O2 dosage of 50mM and silica carrier amount of 40g/L. Under such conditions, the maximum COD removal was 98% at a hydraulic retention time of 90min. The enhancement of biodegradability, evaluated in terms of BOD5/COD ratio increased from 0.16 to 0.7. It was also observed that in fluidized bed solar photo Fenton process, the COD efficiency was 92% whereas in solar photo Fenton process the COD removal efficiency was 67% at 60min. The effluent COD and total suspended solid concentrations were found to be 30mg/L, which met the requirements of the discharge standard.