FNA对短程硝化污泥菌群结构的影响

在SBR反应器增加游离亚硝酸（FNA）预处理单元，投加浓度为1.2mgHNO₂-N/L的FNA进行缺氧搅拌4.5h，连续处理3d，考察短程硝化污泥中FNA对氨氧化菌（AOB），丝状菌和微生物菌群结构的影响.研究表明，FNA对AOB有短时抑制作用，并能够抑制优势丝状菌Candidatus_Microthrix（微丝菌属）和Cytophagaceae（噬纤维菌）的增殖，分别由5.1%和1.1%下降到0.78%和几乎不可见.SVI从281mL/g降低到100mL/g左右.NAR能够维持在90%左右，短程硝化不受到破坏.高通量结果显示，FNA处理后微生物菌群结构多样性与丰度出现下降，但Thauera（陶厄氏菌属）和Ottowia出现了增殖，分别增加到5.58%和7.82%，同步硝化反硝化（SND）作用明显，这使得即便只有短程硝化，总氮去除率依然能达到60%以上.

Effect of FNA on microorganism community structures of partial nitrification sludge

The long-term effects on ammonia-oxidizing bacteria (AOB), filamentous bacteria and microorganism community structures in partial nitrification sludge was investigated by adding a pretreatment unit of free nitrous acid (FNA) in the sequence bath reactor (SBR) for three days at 1.2mg HNO₂-N/L for 4.5. The results showed that FNA had the short-time effect on AOB, Candidatus_Microthrix and Cytophagaceae of the dominant filamentous bacteria were also decreased from 5.1% and 1.1% to 0.78% and almost invisible. Sludge volume index (SVI) maintained at 110mL/g dropping from 281mL/g, and the nitrite accumulation rate (NAR) was kept at around 90%, indicating the partial nitrification was not undermined. Furthermore, High-throughput sequencing results showed that the diversity and uniformity of microorganism community decreased. However, the proliferation of Thauera and Ottowia increased to 5.58% and 7.82%. Simultaneous nitrification and denitrification (SND) had significant effects, and the total nitrogen removal rate was nevertheless maintained more than 60% even only with partial nitrification.