反硝化前置的序批式高浓度活性污泥法深度脱氮处理C/N偏低的市政污水  

High-Efficiency Nitrogen Removal from Low C/N Municipal Wastewater in a Pre-Denitrification Sequencing Batch Bioreactor with High-Concentration Activated Sludge

作　　者：牛明芬[1] 李佳亮 李琪 严群[3] 黄斌[4] 

机构地区：[1]沈阳建筑大学市政与环境工程学院,辽宁沈阳110168 [2]桂林理工大学,广西桂林541004 [3]江南大学环境与土木工程学院,江苏无锡214122 [4]中国科学院沈阳应用生态所,辽宁沈阳110016

出　　处：《净水技术》2017年第A02期56-60,117,共6页Water Purification Technology

基　　金：国家重点研发计划项目(2017YFD08004)

摘　　要：市政污水C/N偏低增加深度脱氮难度与成本,不利于推动内陆缺水地区市政污水再生利用和地下水硝酸盐污染控制。采用铁氧化物促成的高浓度活性污泥,在反硝化前置的SBR中,不外加碳源和不调控pH的情况下处理C/N=4的模拟市政污水。结果表明:缺氧段前置反硝化脱氮进-步降低C/N,降低好氧曝气阶段的曝气需求;在曝气阶段,与单一高强度间隙曝气相比,先弱后强的间歇曝气利于降低异养好氧菌的作用及其对硝化细菌和反硝化细菌的不利影响,在C/N很低的情况下,仍能实现一定强度的硝化与反硝化协同脱氮,总体实现深度脱氮。在换水率为30%、40%和45%的情况下,先弱后强曝气模式下的脱氮效率分别为71.2%、72.4%和70.2%,均优于常规SBR,系统容积负荷分别为0.41、0.33、0.29 kg COD/(m^3·d),显著优于或与常规SBR相当,出水氨氮、总氮浓度均符合国家城镇污水排放一级A标准。Low C/N in municipal wastewater normally increases operation difficulty and cost of high-efficiency nitrogen removal, hampers the reuse of treated wastewater and the control of groundwater nitrate pollution, especially in inland water-shortage areas. Performance of a pre-denitrification SBR with iron oxide-promoted high concentration activated sludge for high efficiency nitrogen removal from C/N=4 simulated municipal wastcwater was investigated without the use of external carbon and pH regulation. Results showed that pre-denitrification coupled to COD removal in hypoxic stage further reduced C/N, reducing the requirement of aera tion in subsequent aeration stage. Compared with single-strong intensity intermittent aeration mode, two-intensity （first weak and then strong） intermittent aeration mode was more effective in limiting the role of heterotrophic aerobic bacteria and their suppressing effects on nitrifying and denitrifying bacteria in aeration stage. As a result, nitrification and denitrification-coupled nitrogen removal could happen to considerable extents, even at the further lowered C/N, overall achieving high efficiency nitrogen removal. At water exchange rates of 30%, 40% and 45%, nitrogen removal efficiencies under two-intensity aeration mode were respectively 71.2%, 72.4% and 70.2%, much better than that of conventional SBR, and volumetric loads of COD were respectively 0.41, 0.33, 0.29 kg/（m3·d）, much better than or equivalent to that of conventional SBR. The levels of ammonia nitrogen and total nitrogen in the effluent all met A-class national discharge standard of municipal sewage.

关 键 词：高浓度活性污泥 前置反硝化SBR 硝化作用 反硝化作用 市政污水 

分 类 号：TU992.3[建筑科学—市政工程]