双系统曝气生物滤池处理玉米青贮渗出液

摘要

Double modified zeolite-biological aerated filter ( BAF) system was selected to treat the corn silage effluent for the removal of COD, NH4+ -N and total nitrogen (TN ). Removal efficiency and effecting factors such as the flow ratio of gas to water, hydraulic retention time (HRT) , organic load and reflux ratio were investigated. The results show that after the biofilm maturation the bio-zeolite system BAF has obvious and stable removal of COD and NH4+ -N; the removal efficiency of COD and NH4+ -N is over 70% and 80% respectively after 23 d. When the flow ratio of gas to water is 2:1, HRT is 12 h, the biofilm has the best activation, and the removal efficiency of COD is 83.4%. Increasing the organic load, the removal of NH4+-N is severely inhibited, which can be reduced from 88. 6% to 32. 7% when the organic mass concentration increases from 160 mg/L to 280 mg/L. The removal of TN is influenced significantly by reflux ratio, by which the removal efficiency increases from 42. 3% to 81. 3% when the reflux ratio is raised from 50% to 300%. But it is not significant for COD and NH4+ -N. The effluent quality of corn silage effluent is obviously improved through the double zeolite-BAF system.%采用双系统改性沸石曝气生物滤池(BAF)反应器对玉米青贮渗出液进行除碳脱氮处理,研究了对COD、氨氮、总氮(TN)的去除效果及其影响因素气水比(流量比)、水力停留时间、有机负荷和回流比.结果表明:挂膜成熟后,沸石生物膜反应器对COD和氨氮有较好的去除效果；挂膜23 d后,COD的去除率可以稳定在70％,氨氮去除率可以稳定在80％以上；当气水比为2∶1,水力停留时间为12 h,生物膜活性达到最高,COD去除率达到83.4％；有机负荷对氨氮去除效果影响较大,有机物质量浓度从160 mg/L提高到280 mg/L时,NH4+-N的去除率由88.6％降为32.7％；回流比对COD、氨氮去除率影响不大,但对TN的去除影响显著,回流比从50％提高到300％,TN去除率从42.3％上升到81.3％.双系统改性沸石BAF反应器明显地改善了玉米青贮渗出液的出水水质.