纯种氨氧化菌短程反硝化特性

Shortcut denitrification characterization of immobilized AOB

以Comamonas aquatica LNL3为研究对象,根据其既能短程硝化又能短程反硝化的特性,采用好氧方式富集和固定化菌种,再以厌氧方式驯化,得到具有高效短程反硝化特性的纯种氨氧化菌。采用扫描电镜对固定化前后的载体进行表征,且用正交试验考察了不同环境因子(温度、pH、碳氮比、溶解氧)对Comamonas aquatica LNL3短程反硝化的影响。结果表明,所用载体与Comamonas aquatica LNL3有良好的亲和性,适于微生物的固定化;环境因子对Comamonas aquatica LNL3短程反硝化影响大小顺序为:温度>pH>DO>C/N;在环境条件改变过程中当温度为35℃,pH=8,C/N=3,DO=2.5 mg/L时,Comamonas aquatica LNL3短程反硝化速率达到最大,为32.63 mg/(L.h);研究结果还表明,Comamonas aquatica LNL3具有好氧反硝化特性,适宜处理低碳氮比废水。

Taking pure ammonia-oxidizing bacteria of Comamonas aquatica LNL3 as the research object, the bacteria was enriched and immobilized under aerobic conditions and then domesticated under anaerobic con- ditions according to its ability of shortcut nitrification and nitrite denitrification. The carriers before and after immobilization were characterized by SEM to illustrate the superior affinity between microorganisms and carriers. The influences of environmental factors （temperature, pH, C/N and DO） on nitrite removal rate of Comamonas aquatica LNL3 were investigated with orthogonal design. The conclusions indicate that the impact order of environmental factors on Comamonas aquatica LNL3 in the nitrite denitrification process is temperature 〉 pH 〉 DO 〉 C/N. The highest nitrite removal rate reaches 32.63 mg/（L · h） when temperature is 35℃ , pH = 8, C/N = 3 and DO = 2.5 mg/L. This study also demonstrates that Comamonas aquatica LNL3has a characterization of aerobic denitrification and it is suitable for wastewater with low C/N ratio.