一株反硝化菌的脱氮性能

Denitrification performance of a denitrifying bacteria strain

从广州市某污水处理厂缺氧段活性污泥中分离筛选出一株反硝化菌,以该菌株为研究对象,鉴定后对该菌株进行脱氮条件最优化实验在此基础上,分析其厌氧氨氧化能力。结果表明:在柠檬酸钠浓度为9 g·L^(-1),KNO_3浓度为1 g·L^(-1),溫度为35℃,pH为6.8的条件下,同时控制接种量为2.5%,即控制初始菌株浓度为10~7 mL^(-1)时,2 d后8号菌能达到87%的最佳NO_3^--N去除率;在厌氧氨氧化能力检测实验中,培养液中生化反应以反硝化作用为主,在第3·5天发现厌氧氨氧化反应,因此推测这株菌具有厌氧氨氧化反应能力。经初步鉴定,该菌株为苏云金芽孢杆菌(Bacillus thuringiensis)。

In order to find new anammox bacteria which can be purified,a strain of denitrifying bacteria was isolated in this study and purified from the activated sludge of the anoxic tank in a sewage treatment plant in Guangzhou.After the qualification test,an experiment for optimizing the denitrification conditions of the strain was conducted,followed by the detection of its anammox ability.By the orthogonal experiment and the test for the best inoculating ratio,the highest nitrate removal rate reached 87%2 days after the inoculation,when the sodium citrate concentration was 9 g·L^-1,KNO3 concentration was 1 g·L^-1,temperature was 35 ℃,pH was 6.8 and the inoculating ratio was 2.5%,which means the initial strain concentration was 10 mL^-1.In the experiment to test the anammox ability,the culture initially prioritized denitrification,but from the third to fifth day,the anammox reaction occurred.It is therefore speculated that the strain,which has been preliminarily identified as Bacillus thuringiensis,has anammox potential.