人工湿地中异养硝化-好氧反硝化菌分离及脱氮除磷特性的研究

Isolation of heterotrophic nitrifying aerobic denitrifying bacteria and characteristics of nitrogen and phosphorus removal in artificial wetlands

为提高对人工湿地养殖尾水处理系统中异养硝化-好氧反硝化菌种类和性能的认知,在其中分离出一株异养硝化-好氧反硝化功能菌株KL1,并研究了其生长影响因子及其脱氮除磷特性。结果表明,菌株KL1经16S rRNA基因同源性分析为假单胞菌属。菌株KL1最佳生长条件如下:最适温度为30~37℃,pH为5~7,碳源为丁二酸钠,C/N为(7∶1)~(7∶18),C/N/P为(14∶2∶1)~(7∶1∶4)。KL1菌株在异养硝化-好氧反硝化过程中,对NH4-N、TN去除率为92%和81%,无NO_(3)-N积累,NO_(2)-N积累量为2%。反硝化过程中对NO_(3)-N和TN去除率为95%和44%,无NH4-N积累。NaNO_(2)为唯一氮源时,NO_(2)-N和TN去除率为56%和41%,无NO_(3)-N积累。NH4Cl为唯一氮源时,除磷率为31%。综上所述,菌株KL1具有较强的异养硝化-好氧反硝化能力及兼具较好的反硝化除磷效果。

In order to improve the removal rate of nitrogen and phosphorus in artificial wetland systems and to enhance the knowledge of heterotrophic nitrifying aerobic denitrifying bacteria species and performance in artificial wetlands,a heterotrophic nitrifying-aerobic denitrifying strain KL1 was isolated from an artificial wetland culture tailwater treatment system to investigate its growth factors and its nitrogen and phosphorus removal performance.The results showed that the optimal growth conditions of strain KL1 were as follows:temperature 30-37℃,pH 5-7,carbon source with sodium succinate,C/N of(7∶1)-(7∶18),and C/N/P of(14∶2∶1)-(7∶1∶4).During the heterotrophic nitrification-aerobic denitrification process of KL1 strain,the removal rate of NH4-N was 92%,and the removal rate of TN was 81%.There was no accumulation of NO_(3)-N,and the accumulation of NO_(2)-N was 2%.In the denitrification process,the NO_(3)-N and TN removal rates were up to 95%and 44%,and no accumulation of NH4-N was found.When NaNO_(2)was used as the only nitrogen source,the removal rates of NO_(2)-N and TN were 56%and 41%,and no NO_(3)-N accumulation was observed.When NH4Cl was used as the only nitrogen source,the phosphorus removal rate was up to 31%.It was found that strain KL1 had strong heterotrophic nitrification-aerobic denitrification ability and good denitrification and phosphorus removal effect.