臭氧氧化工艺对污水处理厂二级出水的处理特性

城镇污水处理厂深度处理单元采用臭氧氧化和臭氧催化氧化工艺可对溶解性难降解有机物进行强化去除。针对臭氧氧化的选择性和臭氧催化氧化去除COD的稳定性，以污水处理厂二级出水为研究对象进行臭氧氧化小试和中试试验，考察不同进水水质情况下臭氧氧化的效果，臭氧氧化后污水可生化性和NH₃-N的变化情况以及臭氧催化氧化去除COD的稳定性。研究结果表明:臭氧氧化对不同水质进水COD的去除效果差异较大，对含有较多饱和有机酸的污水处理效果有限，且臭氧氧化处理后污水BOD₅和NH₃-N均未升高。臭氧催化氧化去除COD的效果与催化剂的吸附饱和程度相关。因此，建议设计城镇污水处理厂臭氧氧化和臭氧催化氧化工艺前需进行小试实验明确对COD的去除效果，臭氧催化氧化小试实验需进行90 d以上或试验至臭氧催化剂达到吸附饱和，不建议在臭氧氧化工艺后增设生物滤池和曝气生物滤池。

CHARACTERISTICS OF OZONE OXIDATION PROCESS ON TREATMENT OF SECONDARY EFFLUENT OF WASTEWATER TREATMENT PLANT

The removal of dissolved refractory organic compounds can be strengthened by ozone oxidation and ozone catalytic oxidation process used as advanced treatment unit in urban sewage treatment plants. In order to explore the selectivity of ozone oxidation and the stability of removal of COD by ozone-catalyzed oxidation, the effects of ozone oxidation under different inlet water quality conditions, the treated effluents biodegradability and NH₃-N were evaluated via ozone oxidation laboratory-scale and pilot-scale test. The results showed that the effect of ozone oxidation on the removal of COD from different influents was quite different. The treatment effect of wastewater with large amount of saturated organic acids was poor. The effluents BOD₅ and NH₃-N didn't increase after ozone oxidation treatment. The effect of ozone catalytic oxidation to remove COD was related to the degree of adsorption saturation of the catalyst. Therefore, it was recommended to conduct a laboratory-scale experiment to clarify the removal effect on COD before designing the ozone oxidation and ozone-catalytic oxidation process of urban sewage treatment plants. The laboratory-scale experiment of ozone catalytic oxidation needed to be performed for more than 90 days or until the ozone catalyst reaches adsorption saturation state. It was not recommended to add biological filters or aerated biological filters after the ozone oxidation process.