Comparative study of ozonation and catalyzed ozonation processes for drinking water treatment by pilot test

The ozone consumption effect and organic removal ability of metal coated cordierite ceramic honeycombs catalytic ozonation (catazone) process and ozonation process were comparatively studied by pilot-scale experiments. By Scan Electron Microscope (SEM), Atomic Force Microscope (AFM), BET, and X-ray photoelectron spectroscopy (XPS) analysis, metal oxides attached to ceramic surface were found to be in the form of crystal cluster, and the pore structure of ceramics was less developed. The air flow statuses of vacant catazone and ozone contactors were inclined to be plug-flow and mixed flow, respectively. Comparing with ozonation process, the ozone mass transfer efficiency of catazone process is lower, and the ozone decomposition efficiency of catazone is higher. The former effect is more obvious in semi-batch experiment, and the latter effect is more obvious in continuous-flow experiment. Unsaturated organics removal efficiencies of the two oxidation processes are similar, and are less affected by dissolved ozone concentration when it is higher than 1 mg/L. More dissolved organics were detected in catazone process in continuous-flow reaction, and more CH₃Cl₃ formation potential (CH ₃Cl₃FP) was removed by catazone in semi-batch mode, especially in the water with lower UV₂₅₄.