污泥臭氧原位减量工艺中抗生素的去除

Removal of Antibiotics During In-situ Sludge Ozone-reduction Process

建立了两套小试规模的序批式反应器,一套作为污泥臭氧原位减量系统,另一套作为控制系统.通过两系统的长期运行(90 d)考察了污泥臭氧原位减量工艺对9种典型抗生素(四环素、土霉素、强力霉素、诺氟沙星、氧氟沙星、环丙沙星、洛美沙星、恩诺沙星和阿奇霉素)的去除效果.结果表明,进水中目标抗生素的存在(9种抗生素各100μg·L^(-1))并未对活性污泥去除COD、总氮、氨氮和总磷的效果产生显著影响.污泥臭氧原位减量系统出水中目标抗生素浓度在运行期间保持相对稳定,且与控制系统接近;但污泥中目标抗生素浓度则显著低于控制系统.质量衡算表明目标抗生素在两系统内的输入和输出逐渐达到平衡,臭氧降解和剩余污泥排放分别为减量和控制系统中目标抗生素的主要去除途径.污泥臭氧处理单元可以降解减量系统入水中83%的目标抗生素,而控制系统入水中82%的目标抗生素则随剩余污泥排放.因此,污泥臭氧原位减量工艺可以明显削减活性污泥系统中抗生素的排放,具有重要的实际意义.

Two sequencing batch reactors were established at bench-scale,with one used as an in-situ sludge ozone-reduction system and the other as a control system. Both systems were continuously operated for 90 days to comparatively investigate the elimination of nine typical antibiotics（ i. e.,tetracycline,oxytetracycline,doxytetracycline,norfloxacin,ofloxacin,ciprofloxacin,lomefloxacin,enrofloxacin,and azithromycin） during the in-situ sludge ozone-reduction process. Results indicated that the presence of target antibiotics in the influent（ 100 μg·L^（-1） each） had an insignificant influence on the removal of COD,total nitrogen,ammonia,and total phosphorus by the activated sludge. The antibiotic concentrations in the effluent of the reduction system remained fairly stable over the entire operation period,and were similar to those in the effluent of the control system; however,the antibiotic concentrations in the sludge of the reduction system were obviously lower than those in the control system sludge. Mass balance calculations revealed that the input and output of target antibiotics gradually approached balance in both the systems. Ozone degradation and excess sludge discharge were the main pathways for target antibiotic removal in the reduction and the control systems,respectively. The influent antibiotics could be degraded by 83% in the sludge ozonation module of the reduction system,while 82% of the influent antibiotics were discharged with excess sludge in the control system. Therefore,the in-situ sludge ozone-reduction process could greatly reduce the release of antibiotics from the activated sludge system,which is of great importance in practice.