Study on full-scale H2O2/O3–UBAC process for removing organic matters in drinking water treatment

Abstract

Ozone–biological activated carbon process (O3–BAC) is an advanced drinking water treatment technology that has been widely used. The combined process of O3/H2O2-upflow BAC filter (UBAC)—sand filter has been adopted by a drinking water treatment plant. The paper summarizes the effect of advanced oxidation process (O3 and O3/H2O2) on the overall combined process in two seasons. The influence of different O3/H2O2dosages on the effluent water quality is investigated and the effectiveness of the combined process is analyzed. The results indicate that O3 can effectively decompose organic matters in water and increase the biodegradability of dissolved organic carbon. The organic matters removal rate of combined process increases as ozone dosage increases. Biodegradable dissolved organic carbon (BDOC) after ozonation increases by 30, 93, and 101% with increasing ozone dosages from 1.0, 1.5 to 2.0 mg/L. The removal rates of BDOC by the combined process reached 39, 45, and 73%, respectively. H2O2/O3 does not give better effect than O3 alone. Turbidity removal rate by sand filtration remains stable, which is above 87%. Higher temperature is favorable to microbial degradation by UBAC and sand filter.