内循环式A/O/IAT-IAT工艺处理效果与微生物群落结构关系

对内循环式A/O/IAT-IAT同步脱氮除磷工艺在2种不同工况下的脱氮除磷效果和微生物群落结构之间的关系进行了探讨.工况1(HRT为20h,SRT为3.5 d),出水ρ(COD_Cr),ρ(NH₄+-N),ρ(PO₄3-P)分别为9.2～30.6,3.2～7.6和0.2～0.5 mg/L;工况2(HRT为15 h,SRT为5.0 d),出水ρ(COD_Cr),ρ(NH₄+-N),ρ(PO₄3-P)分别为1.2～23.0,0.1～2.1和0.3～1.3 mg/L.试验结果表明:与工况1相比,工况2 NH4+-N和SS平均去除率分别上升了12%和59.4%,而PO₄3-P却下降了7.9%.同时,2种工况下活性污泥特性也发生了变化,SV由75%～80%下降到37%～54%.2种工况下微生物优势菌没有发生明显改变,基本为变型杆菌;工况1活性污泥中优势微型动物为着生型原生动物,而工况2中则以硝化指示生物为主,且着生型后生动物的密度是工况1的10倍. 

Correlation between Treatment Performance and Microorganism Community Structure in Inside-Circle A/O/IAT-IAT Process

The correlation between the treatment performance and the microorganism community structure in inside-circle A/O/IAT-IAT process was investigated. The reactor was operated in two different modes. In the mode 1 (HRT was 20 h， SRT was 3.5d)，the effluent COD_Cr， NH₄+-N，PO₄3--P were 9.2～30.6，3.2～7.6，0.2～ 0.5 mg/L，respectively; in mode 2 ( HRT was 15 h，SRT was 5.0 d)，the effluent CODCr，NH₄+-N， PO₄3-P were 1.2～23.0，0.1～2.1，0.3 ～1.3 mg/L， respectively. The results revealed that compared to the mode 1， the removal rates of NH4+-N，SS raised 12% and 59. 4％ respectively， but PO₄3-P reduced 7.9% in the mode 2. The activated sludge characteristic and the microorganism community structure all changed in the two modes. The activated sludge SV declined from 75%～80% to 37%～54%. The dominant bacteria of the activated sludge were Proteobacteria in the two modes，but the dominant microzoa were fixed protozoan in the mode 1，and Arcella vulgaris in the mode 2. The density of fixed metazoan in the mode 2 was ten times of that in the model 1.