Based on the hypothesis of reducing sludge production under cryptic growth conditions, ozone was used as cell lysis agent to treat excess sludge,and then the ozonated supernatant was returned to the aeration tank. The...Based on the hypothesis of reducing sludge production under cryptic growth conditions, ozone was used as cell lysis agent to treat excess sludge,and then the ozonated supernatant was returned to the aeration tank. The results show that COD and NH+4-N removal efficiencies in ozonation process were 87.96% and 84.42%, respectively. Meanwhile, a low excess sludge yield coefficient of 0. 113 ( g SS/g COD removed) was obtained. Compared with that of the control test, the process configuration decreased the excess sludge production by 51.3%.展开更多
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 experimen...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 efflciencies 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 CH3CI3 formation potential （CH3CI3FP） was removed by catazone in semi-batch mode, especially in the water with lower UV254 .展开更多
文摘Based on the hypothesis of reducing sludge production under cryptic growth conditions, ozone was used as cell lysis agent to treat excess sludge,and then the ozonated supernatant was returned to the aeration tank. The results show that COD and NH+4-N removal efficiencies in ozonation process were 87.96% and 84.42%, respectively. Meanwhile, a low excess sludge yield coefficient of 0. 113 ( g SS/g COD removed) was obtained. Compared with that of the control test, the process configuration decreased the excess sludge production by 51.3%.
文摘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 efflciencies 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 CH3CI3 formation potential （CH3CI3FP） was removed by catazone in semi-batch mode, especially in the water with lower UV254 .
