污水再生工艺去除病原体效果的评价

为考察常用城市污水再生回用工艺去除病毒的效果,采用柯萨奇B3型病毒(CoxB3)作为肠道病毒示踪剂进行试验.首先向污水厂二级处理出水中人工投加已知浓度的病毒,然后分别采用混凝/沉淀/过滤、超滤、氯消毒和臭氧消毒对其进行处理,并分析处理前后病毒的组织培养半数感染剂量(TCID50).结果表明,混凝/沉淀/过滤对大肠菌的去除率为2-lg～3-lg,对柯萨奇病毒的去除率约为1.83-lg;氯消毒和臭氧消毒可以有效杀灭大肠菌,在消毒剂浓度为1～10mg/L、余氯浓度为1～6 mg/L、pH为6～7的条件下,氯消毒对柯萨奇病毒的去除效果不佳,臭氧消毒对柯萨奇病毒的去除率则随臭氧浓度的不同而在1.33-lg～3.83-lg变化;超滤可有效去除大肠菌,对柯萨奇病毒的去除率为2.33-lg.

Assessment on Wastewater Reclamation and Reuse Process for Pathogen Removal

Coxsackie B3 (CoxB3) was used as enteric virus tracer to assess the effect of urban wastewater reclamation and reuse technology on virus removal. Firstly, the virus with known concentration was added to the secondary effluent from wastewater treatment plant, and then coagulation/sedimentation/filtration, ultrafiltration, chlorine disinfection, and ozone disinfection were used to treat the effluent. Virus assay was carried out by the Tissue Culture Infectious Dose (TCID_ 50) technology before and after the treatment. The result shows that the removal rate of coagulation/sedimentation/filtration for coliform bacteria is 2-lg-3-lg and for CoxB3 is 1.83-lg; both chlorine and ozone disinfection can effectively kill the coliform bacteria. Under the conditions of chlorine dosage 1-10 mg/L, residual chlorine 1-6 mg/L, and pH 6-7, the chlorine disinfection has little removal effect for CoxB3, and ozone disinfection has removal rate for CoxB3 varying from 1.33-lg to 3.83-lg dependent on the ozone concentration. Ultrafiltration can remove effectively the coliform bacteria and the removal rate for CoxB3 is 2.33-lg.