一株脱氮细菌鉴定及其效果研究

Identification and Effect of a Denitrifying Bacterial Strain

针对传统人工湿地治理污染河湖水工艺中存在的脱氮效率低、环境安全性差等问题,从污水处理厂生化池污泥中分离纯化获得菌株TY(CGMCC1.18865,该菌种已于2020年在中国普通微生物菌种保藏中心入库),通过配水试验,验证菌株脱氮特性,并进一步以火山岩为填料,采用湿地模拟系统装置对比附配TY菌的湿地系统与传统湿地系统对污染水体的脱氮效果的差异;通过16S rRNA基因序列分析,鉴定获得的菌株TY,同时对其表现出的反硝化作用进行分析研究。结果表明:分离获得的TY菌株为假单胞菌属(Pseudomonas sp.),配水试验中对氨氮和总氮的去除率分别为84.2%和93.6%。通过对模拟湿地系统出水氨氮、总氮和化学需氧量(COD)监测,发现30 d平均去除率分别可提升至94.3%、88.0%和82.3%,较传统湿地分别提高27.9%、28.8%和7.3%。研究表明,TY菌脱氮过程中有少量的硝态氮和亚硝态氮的积累,可降低对环境的不利影响、有利于脱氮反应连续进行,从而提高人工湿地脱氮效率,具有进一步探究的前景。

In order to solve the problems of low efficiency of nitrogen removal and poor environmental safety in the traditional constructed wetlands for treating polluted water.The strain TY was isolated and purified from sludge in biochemical treatment plant of sewage treatment plant(CGMCC1.18865.The strain was put into storage in China General Microbiological Culture Collection Center in 2020),through the water distribution test,the denitrification characteristics of the strain were verified,and the volcanic rock was used as the wetland filler,and the wetland simulation system with volcanic rock as filler was used to compare the denitrification effect between the wetland system with TY bacteria and the traditional wetland system;TY strain was identified by 16S rRNA gene sequence analysis,and its denitrification was analyzed and studied.The results showed that the isolated TY bacteria were Pseudomonas sp.,and the removal rates of ammonia nitrogen and total nitrogen in water distribution test were 84.2%and 93.6%.Through the monitoring of ammonia nitrogen,total nitrogen and chemical oxygen demand(COD)in the effluent of the simulated wetland system,it is found that the average removal rate in 30 days can increase to 94.3%,88.0% and 82.3%,which is 27.9%,28.8% and 7.3% higher than those of the traditional wetland.The research showed that there was a small amount of nitrate and nitrite accumulation in the denitrification process of TY bacteria,which can reduce the adverse impact on the environment and facilitate the continuous denitrification reaction,so as to improve the denitrification efficiency of constructed wetland,which has the prospect of further exploration.