臭氧-曝气生物滤池深度处理垃圾焚烧渗滤液可行性研究

摘要

This study attempted to substitute the nanofiltration (NF)- reverse osmosis (RO) process with ozonation-biological aerated filter (BAF) in the advanced treatment of leachate from municipal solid wastes incineration plant. Semi-batch ozonation test in a 10 L column reactor demonstrated that the biodegradability of test leachate improved as ozonation time increased, 91%of color and 64%of UV254 could be removed within 15 min, the COD removal rate was 59% within the first 45 min, but thereafter slowed down with a removal rate of 77% at 120 min. Continuous flow test revealed that 1 h of ozonation (78.8 mg/L, 3.7 mL/min) followed with BAF (HRT=4.3h) could remove 75%of COD, 95%of color and 89%of UV254 from the leachate. The effluent COD remained below the discharge standard during 2/3 of the operational time and the effluent color was able to meet the discharge standard. The above results suggested the possibilities of substituting NF-RO with ozonation-BAF to treat waste leachate. The results of GC-MS indicated that the dominant pollutants in the test water were alkanes, aromatic compounds and heterocyclic compounds containing nitrogen, and ozonation-BAF was effective in removing the later two kinds of pollutants, but difficult in removing alkanes.%研究了臭氧-曝气生物滤池(BAF)代替纳滤和反渗透深度处理垃圾焚烧渗滤液达标排放的技术可行性.半间歇臭氧氧化试验表明,实验用水的可生化性随着氧化时间的增加而增加,色度及UV254,15min内去除率分别达91%和64%；氧化时间为45min时COD去除率59%,45min后COD去除较慢,120min时去除率77%.确定臭氧氧化时间为1h,在同样臭氧浓度与流量下进行了臭氧-BAF处理垃圾焚烧渗滤液的连续实验.结果发现,此工艺对COD、色度和UV254的去除率分别可达75%,95%和90%,其中2/3运行时间里COD低于排放标准100 mg/L.其中出水色度可稳定保持在40度以下达标排放.经过进一步优化,臭氧-BAF有望用于垃圾焚烧渗滤液的达标处理.GC-MS检测表明烷烃,芳香族化合物及含氮杂环化合物是试验用水的主要污染物,臭氧-BAF能够有效去除后两类化合物,但难以去除烷烃.