【摘要】 对序批式膜生物反应器(MBR)处理前后医院污水中的AOX进行了比较,分析了cRt值对不同水质中AOX生成量的影响及相应的生物毒性.结果表明,序批式MBR对医院污水中AOX的去除率达到63.6%,其中膜截留占14.5%;要获得相同的cRt值,原污水所需的投氯量显著高于MBR出水,相应生成的AOX浓度也较高;通过曲线拟合发现,随着cRt的增长,医院原污水中AOX浓度呈指数增长,而MBR出水呈线性关系.以粪大肠杆菌为指示微生物,要达到医院污水微生物排放标准(GB 18466-2005),医院原污水所需cRt为5.5(mg.h)/L,而MBR出水只需cRt为0.007 5(mg.h)/L,其相应的生物毒性分别为40.39μg/L和8.96μg/L(以K2Cr2O7计),AOX浓度分别为607.1μg/L和102.5μg/L.更多还原

【Abstract】 Adsorbable organic halogen compounds（AOX） exist persistently in the aquatic environment,and accumulate in the food chain.Some of them are toxic for humans and other organisms.However,hospital wastewater is considered as an important source of AOX in municipal wastewater.The aim of this study was to evaluate the generation of AOX both in a raw hospital wastewater and the effluent from a membrane sequencing batch reactor,also the effect of c_Rt value and the bio-toxicity were investigated.The results show that the removal of AOX in the hospital wastewater is 63.6% after treated by the membrane sequencing batch reactor,and the contribution of membrane rejection accounts for 14.5%.The concentration of AOX in the raw hospital wastewater is much higher than that of the effluent from membrane sequencing batch reactor at the same value of c_Rt for its higher chlorine-demands.Along with the increasing of c_Rt value,the fitting curves of AOX present exponential growth for the raw hospital wastewater,while linearity relation for the effluent from membrane sequencing batch reactor.To meet the requirement for indicative microorganism（fecal coliform） in the Discharge Standard of Water Pollutants for Medical Organization（GB 18466-2005）,the demands of c_Rt value for the raw hospital wastewater and the effluent from membrane sequencing batch reactor are 5.5（（mg·h）/L） and（0.007?5）（（mg·h）/L） respectively,the bio-toxity by acute toxicity test with Daphnia magna are 40.39（μg/L）（K₂Cr₂O₇） and 8.96（μg/L）（K₂Cr₂O₇）,and correspondingly the concentration of AOX produced are 607.1（μg/L） and 102.5（μg/L）.更多还原