MBR-SNAD工艺处理生活污水效能及微生物特征

Performance and microbial characteristic of SNAD process for treating domestic sewage in a membrane bioreactor

为考察基于膜生物反应器(MBR)的同步亚硝化厌氧氨氧化反硝化(SNAD)工艺处理生活污水的可行性,在SNAD工艺稳定运行的MBR中逐步加入生活污水,同时微调曝气量及HRT等参数,考察生活污水中污染物的去除效果,通过物料衡算计算不同阶段反应器内的脱氮路径,同时通过克隆-测序技术分析了微生物种群特征.结果表明,MBR-SNAD工艺可以实现生活污水中C、N及SS的同时高效去除,总氮去除负荷达0.65 kg/(m3·d),出水氨氮小于5 mg/L;COD去除率达87%,出水COD小于50 mg/L;浊度去除率达99%,出水浊度在1 NTU以下,SS在10 mg/L以下,达到城镇污水处理厂污染物排放标准(GB18918—2002)的一级A排放标准.反应器中存在约12%的反硝化脱氮和88%的全程自养脱氮(CANON),实现了异养脱氮和自养脱氮的协同合作.好氧氨氧化菌、厌氧氨氧化菌和反硝化菌共存于系统内.MBR-SNAD是处理生活污水的适宜工艺.

Simultaneously partial nitrification, anammox and denitrification （SNAD） process was used for treating domestic sewage in a membrane bioreactor （MBR）. Domestic sewage was gradually pumped into the system, removal trend of the pollutants were evaluated via the changing of operational HRT and air flow. The nitrogen removal pathway was analyzed via the mass balance analyze studying, and microbial characteristics via clone- sequencing detection. Results suggested that a simultaneous removal of C, N and SS was achieved in the system, with the nitrogen removal rate to 0.65 kg/（ m3 -d） , effluent ammonia below 10 rag/L; COD removal efficiency to 87%, effluent COD below 50 mg/L; turbidity removal to 99%, effluent turbidity below 1 NTU, and SS below 10 mg/L, which met the demand of the first grade A standards of Urban Sewage Disposal Plant Contamination Integrated Discharge Standard （GB18918- 2002）. Denitrifieation contributed to 12% nitrogen removal while （completely autotrophic nitrogen removal over nitrite, CANON ） contributed to 88%, and AOB, anammox and denitrifiers coexisted in the reactor.