城市污水厂活性污泥强化自养反硝化菌研究

采集北京高碑店城市污水厂的反硝化污泥样品，以硫磺作为电子供体进行驯化培养. 测定污泥的增长率来确定污泥活性，分别测定NO^-₃-N、SO^2-₄浓度来确定硝酸盐的去除效率和硫酸盐生成速率. 当硝酸盐去除率达到90%以上时，提取污泥中微生物总DNA，构建16S rRNA基因片段克隆文库来分析细菌群落结构. 结果表明，污泥的增长率为0.177 g/(L·d)，污泥中硝酸盐浓度与时间的关系符合一级反应. 污泥中细菌类群主要为Beta-Proteobacteria、Deta-Proteobacteria、Gamma-Proteobacteria和Unclassified bacteria，其中Beta-Proteobacteria类细菌占主导地位. 在成熟的反硝化污泥中，自养反硝化菌Thiobacillus denitrificans占所占比例高达48.65%. 此外，反应器中还存在Denitratisoma sp.、Curvibacter sp.、Thermomonas sp.、Geobacter sp.等细菌. 对自养反硝化污泥中细菌多样性的研究有利于优化反应条件，从而提高污泥的硝酸盐去除率.

Experimental Study of Autotrophic Denitrification Bacteria Through Bioaugmentation of Activated Sludge from Municipal Wastewater Plant

Activated sludge of municipal wastewater treatment plant was domesticated by sulfur as the electron donor under autotrophic. The sludge activity was determined by measuring growth rate of sludge. The removal efficiency of nitrate and sulfate production efficiency were analyzed by continuously measuring the concentration of NO^-₃-N and SO^2-₄. When the removal efficiency of nitrate was more than 90%, 16S rRNA genetic libraries were built up to compare their microbial biodiversity. The growth rate of sludge is 0.177 g/(L·d). The relation between concentration of nitrate and time meets first order reaction kinetics. The bacteria in the sludge affiliated with Beta-Proteobacteria, Deta-Proteobacteria, Gamma-Proteobacteria and Unclassified bacteria. Beta-Proteobacteria is the main phylum in the sludge. Bacteria related to Thiobacillus denitrificans from denitrifying bioreactor perform 48.65%. In addition, the bacteria of Denitratisoma sp., Curvibacter sp., Thermomonas sp., Geobacter sp. are existed in the sludge. The study of autotrophic denitrifying bacteria diversity is conducive to optimization of reaction conditions and efficient removal of nitrate.