抄録
The efficiencies of chemical oxidation of organic matter in genuine secondary treated municipal wastewater by using O3, O3/UV, O3/TiO2, UV/TiO2, and O3/UV/TiO2 methods were compared experimentally. Effects of carbonates on these efficiencies were also investigated. Elimination of carbonates from the water increased TOC reduction efficiency for all the methods. The effect of the carbonates was less significant for the O3 method than for the other methods. The O3/UV method was the most effective for reducing TOC under both carbonate-present and decarbonated conditions. The least effective method was the O3/TiO2 under the carbonate-present condition, and the UV/TiO2 method under the decarbonated condition. The catalytic ozone process (O3/TiO2) showed a tendency to increase the ozonation at the beginning of the reaction under the decarbonated condition, but the addition of the TiO2 catalyst inhibited the ozonation under the carbonate-present condition. The photocatalytic oxidation process (UV/TiO2) did not reduce TOC compared with the other methods, but it could reduce TOC over a long time ; namely after six hours of treatment, TOC reduction efficiency reached 60% under the decarbonated condition and 30% under the carbonate-present condition. And the O3/UV/TiO2 method did not show a synergistic effect of ozonation and photocatalytic oxidation.
