一株异养硝化—好氧反硝化菌株的分离鉴定及脱氮特性研究

发布时间：2018-11-18 14:57

【摘要】：本研究从汾河污泥中成功筛选出一株脱氮效果良好的异养硝化-好氧反硝化菌,将其命名为ZH-1。经过生理生化鉴定和菌株16S rDNA序列分析,确定菌株ZH-1为施氏假单胞菌(Pseudomonas stutzeri),并建立了系统发育树。菌株的异养硝化特性研究表明:菌株ZH-1可以将NH4~+-N直接转化为气态物质而释放,表现出良好的硝化作用。研究菌株ZH-1在不同培养条件下去除NH4~+-N的能力,实验得出菌株ZH-1在pH为8.0,接种量为2%,摇床转速为100rpm,C/N为12,NH4~+-N浓度为100.0 mg/L,培养温度为30°C时对NH4~+-N的降解效果最好,去除率达到99%。在好氧条件下,当初始硝酸钾浓度约为3g/L时,菌株ZH-1表现出很好的反硝化作用,去除率可以达到100%,且在培养结束没有检测到亚硝酸盐的存在。另外,研究菌株ZH-1在不同条件下去除NO_3~--N的能力,发现菌株ZH-1在pH为8.0,接种量为4%,转速为100rpm,C/N为8,培养温度为30°C,可以将约为419.0mg/L的NO_3~--N降解至1.4mg/L,去除率也可达到99.67%。利用菌株ZH-1对实际污水脱氮效果进行了初步的实验。发现在未灭菌的污水中不添加小分子碳源和添加小分子碳源的状态下,菌株ZH-1对实际污水的脱氮能力分别为34.95%和68.51%,这也说明菌株对实际污水脱氮效果受到可利用碳源的影响;在灭菌污水中不添加小分子碳源和添加小分子碳源的状态下,菌株ZH-1对污水的脱氮能力分别为14.73%和65.5%。通过比较也说明了所取得实验污水里本身存在的一些菌也具有一定的脱氮能力,添加菌株ZH-1后可以促进污水中氨氮含量的降低。所有的试验表明,分离得到的菌株ZH-1表现出较强的同时硝化反硝化的能力,在未来含氮废水处理方面成为一株可利用的候选菌株,将来具有广阔的应用前景。
[Abstract]:In this study, a heterotrophic nitrification-aerobic denitrifying strain was successfully screened from the sludge of Fenhe River and named ZH-1.. After physiological and biochemical identification and 16s rDNA sequence analysis, the strain ZH-1 was identified as Pseudomonas sp. (Pseudomonas stutzeri), and phylogenetic tree was established. The study of heterotrophic nitrification of the strain showed that strain ZH-1 could directly transform NH4~ N into gaseous substance and release it, showing a good nitrification effect. The ability of strain ZH-1 to remove NH4~ N under different culture conditions was studied. The results showed that the strain ZH-1 was 8. 0 at pH, inoculation amount was 2 and rotation speed was 100rpmcn = 12nNH4 ~ -N, and the concentration of strain ZH-1 was 100.0 mg/L,. When the culture temperature was 30 掳C, the degradation efficiency of NH4~-N was the best, and the removal rate reached 99%. Under aerobic conditions, when the initial concentration of potassium nitrate was about 3g/L, strain ZH-1 showed a good denitrification effect, the removal rate could reach 100%, and no nitrite was detected at the end of culture. In addition, the ability of the strain ZH-1 to remove NO_3~--N under different conditions was studied. It was found that the ZH-1 of the strain was 8.0 at pH, the inoculation amount was 4, the rotational speed was 100 rpm ~ (-1) C / N = 8, and the culture temperature was 30 掳C. The NO_3~--N about 419.0mg/L can be degraded to 1.4 mg / L, and the removal rate can reach 99.67%. A preliminary experiment was carried out on the nitrogen removal effect of actual wastewater by using strain ZH-1. It was found that the denitrification ability of the strain ZH-1 to actual sewage was 34.95% and 68.51%, respectively, without adding small molecular carbon source and adding small molecular carbon source in unsterilized sewage. This also shows that the nitrogen removal effect of the strain on the actual sewage is affected by the available carbon source. The denitrification capacity of the strain ZH-1 was 14.73% and 65.5%, respectively, when there were no small molecular carbon sources or small molecular carbon sources added in the sterilized sewage. The comparison also showed that some bacteria contained in the sewage also had certain denitrification ability, and the addition of strain ZH-1 could promote the decrease of ammonia nitrogen content in the sewage. All the experiments showed that the isolated strain ZH-1 showed strong ability of simultaneous nitrification and denitrification, and was a candidate strain for the treatment of nitrogen-containing wastewater in the future, and had a broad application prospect in the future.
【学位授予单位】：山西师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X172;Q93

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