摘要:目前，随着水体富营养化的加剧，对废水生物脱氮技术的研究提出了新的要求和挑战。与传统生物脱氮工艺相比,短程硝化反硝化生物脱氮工艺可节约供氧量25%左右；节约反硝化所需碳源40%左右；减少污泥生成量，减少硝化过程的投碱量；缩短反应时间。因此，研究短程反硝化可以为生物脱氮提供新的思路，具有重要的现实意义。

本文采用从污水厂污泥中分离到的短程反硝化细菌为研究对象，通过反复富集、分离等方式获得纯种；采用紫外诱变的方式，筛选出亚硝酸盐氮去除能力高、繁殖速度快的短程反硝化细菌；研究短程反硝化细菌种群增长动力学，对不同基质条件下的短程反硝化菌的动力学进行研究；采用固定化细胞技术，固定诱变筛选出的优良菌种，研究短程反硝化细菌固定化条件。实验结果表明：富集、分离得到的纯菌株，经紫外线照射30min，此时的诱变效果最好，筛选得到优势菌群；温度和pH会对短程反硝化速率造成影响，最佳温度为30～40℃，最佳pH在8.3附近。固定化短程反硝化菌时，海藻酸钠最适浓度为4.5%，氯化钙最适浓度为2.0%，25℃培养7～20d，亚硝酸盐氮去除效果最好。

关键词 生物脱氮；短程反硝化菌；筛选；诱变；固定化

Abstract:At present, with the intensification of eutrophication, the study of wastewater biological nitrogen removal technology puts forward new requirements and challenges. 

　　　Compared with the traditional biological denitrification process, shortcut nitrification denitrification biological denitrification process can save about 25% oxygen; Save denitrification carbon source required by about 40%; To reduce the sludge production, reduce nitrification process for alkaline; Shorten the reaction time. So the short-range denitrification can provide new ideas for biological denitrification, and has important practical significance.

　　　In this paper from the sewage plant sludge to short-range denitrifying bacteria as the research object, through repeated enrichment, separation and other way to get pure; With the method of ultraviolet mutagenesis, screening high nitrite nitrogen removal capacity, fast breeding short-range denitrifying bacteria; Short-range denitrifying bacteria population growth dynamics, study on the different substrate conditions of short-range kinetics of denitrifying bacteria was studied; Using immobilized cell technology, fixed mutation screening of strains, the short-range denitrifying bacteria immobilization conditions. Experimental results show that the enrichment, separation of pure strains, 30 min after the ultraviolet irradiation, the mutagenic effect best, screening get advantage bacterium group; Temperature and pH can affect short-range denitrification rate, the best temperature for 30 to 40 ℃, the best pH near 8.3. Immobilized short-range denitrifying bacteria, the optimal concentration of sodium alginate is 4.5%, the optimal concentration of calcium chloride 2.0%, 25 ℃ 7 ~ 20 day and nitrite nitrogen removal effect is best.

Keywords  biological denitrification  short-range denitrifying bacteria  screening  mutagenic  immobilized