一株好氧反硝化菌的分离及特性研究

利用富集培养的方法从城镇污水处理厂的活性污泥中分离到1株好氧反硝化菌,命名为CW。通过形态、生理生化特征和16SrRNA基因序列分析,初步鉴定为睾丸酮丛毛单胞菌(Comamonas testosteroni)。生长特性的研究表明最佳碳源是乙酸钠,最佳碳氮比10:1,最佳DO4.0～6.0mg/L,在此条件下培养24h后,对初始浓度108mg/L的硝酸盐降到27mg/L,去除率达到75%,亚硝酸盐积累仅为4mg/L。以组合载体为填料,挂膜后对污水进行处理,HRT48h,DO5.0mg/L左右,氨氮去除率达到95%左右,最终的NO3-N和NO2-N分别由起始的40～52mg/L和21～28mg/L降为--12～15mg/L和7～9mg/L。

Study on Isolation and Characteristics of an Aerobic Denitrifying Bacteria

A bacterial strain CW, capable of denitrification under aerobic conditions, was isolated from the activated sludge of the municipal sewage treatment plant by enrichment culture. Srain CW was identified as Comamonas testosteroni according to its morphological characteristics, physiological and biochemical characteristics, and the analysis of partial 16S rRNA gene sequence. The characteristics were researched, the results showed that the optimal carbon source was sodium acetate, the optimal C/N ratio was 10：1, the optimal DO was at the range of 4.0～6.0 mg/L. Under the above conditions, the initial nitrate concentration was reduced from 108 mg/L to 27 mg/L, nitrate removal rate reached 75%, and nitrite was in a low concentration of 4 mg/L, an incubation time of 24 h. The wastewater was dealt with after the combined carrier as the packing was filmed, when HRT was 48 h and DO was about 5.0 mg/L, the removal rate of ammonia nitrogen was up to about 95%, the final concentrations of nitrate-nitrogen and nitrite-nitrogen were merely in the range of 12~15mg/L and 7~9 mg/L, respectively, which were obviously lower than the initial concentrations in the range of 40~52 mg/L and 21~28 mg/L.