2018年4月，生态环境部印发《关于加强固定污染源氮磷污染防治的通知》，《通知》中明确指出氮磷是水污染防治过程中影响流域水质改善的主要因素。在氮磷要求与管理日益严格的环境下，解决问题的主要途径是实现高效脱氮除磷。反硝化聚磷菌的发现和反硝化脱氮除磷的理论研究为污水同步脱氮除磷深度处理工艺的改革和创新提供了新的思路和视角。反硝化脱氮除磷技术克服了传统处理技术中菌种碳源竞争的矛盾，实现“一碳两用”，对污水处理工艺具有重要指导意义，是实现水体氮磷污染有效治理的手段和措施。本文以从污水处理厂活性污泥中筛选出的具有同步脱氮除磷性能的目标菌株作为研究对象，对其进行关键因子影响研究和工程化应用技术研发，为新型污水脱氮除磷工艺提供数据支撑。本论文研究主要分为三部分：菌株筛选与菌属鉴定、菌属关键因子影响特性研究、菌属固定化及固定化优化研究，得到的结论主要有： 第一部分：利用传统微生物技术，通过一系列筛选试验从污水处理厂活性污泥中分离、筛选及纯化出一株具有同步脱氮除磷效应的反硝化聚磷菌，该菌株革兰式染色呈阴性，菌体的顶端无鞭毛，无芽孢，16S rDNA高通量测序分析鉴定该菌株为不动杆菌属（Acinetobacter）。 第二部分：从不同初始pH值、不同电子受体类型、不同电子受体浓度以及不同初始接种比等关键因子进行其对该菌属脱氮除磷性能的影响研究。实验结果表明：反硝化脱氮除磷过程更容易发生在中性和碱性环境下；除了氧气外，硝酸盐和亚硝酸盐都可作为电子受体，实现缺氧条件下吸磷过程；不同的是，在亚硝酸盐体系中的微生物效应比硝酸盐电子受体体系强；在一定范围内，较高的电子受体浓度可以促进缺氧磷吸收与磷去除；但是，当浓度过高，会对磷去除起到抑制作用，如在pH=9，ρ（硝酸盐）=50mg/L和ρ（亚硝酸盐）=5mg/L时，磷酸盐的去除受到抑制。确定最佳接种比为微生物初始接种比2%体系，在磷酸盐和硝态氮初始浓度分别为25mg/L和60mg/L条件下，其磷酸盐与硝态氮去除率为90%和30%；且有脱氮除磷总效率排序：NP2%>NP1%>NP10%≈NP15%>NP5%。 第三部分：对菌株进行固定化及其固定化小球条件优化研究，主要包括载体对比、材料优化以及性能测试三部分。以海藻酸钠和聚乙烯醇为包埋剂，选择硅酸钙为固定化载体，利用Design-Expert软件中的Box-Behnken Design设计实验进行材料优化，实验表明添加硅酸钙载体可以明显提高固定化小球的脱氮除磷效率，最高可达75%。最终确定在制备反硝化聚磷菌固定化小球优化过程中以10#实验方案为最佳方案，其中聚乙烯醇浓度6%、海藻酸钠浓度1%、硅酸钙载体浓度2%。磷酸盐和硝态氮初始浓度分别为100mg/L和280mg/L条件下，10#小球磷酸盐、硝态氮以及累加效应去除率分别为69%、41%和110%。三因素影响分析结果表明：海藻酸钠浓度、聚乙烯醇浓度、硅酸钙浓度三因素对固定化小球磷酸盐去除率影响大小顺序依次是硅酸钙>聚乙烯醇>海藻酸钠；对固定化小球硝态氮去除率作用大小顺序依次是硅酸钙≈海藻酸钠>聚乙烯醇。

In April 2018, the Ministry of Ecology and Environment issued the Notice on Strengthening Prevention and Control of Nitrogen and Phosphorus Pollution from Fixed Pollution Sources. The Circular clearly states that nitrogen and phosphorus are the main factors affecting water quality improvement during the prevention and control of water pollution. In the environment where nitrogen and phosphorus requirements and management are increasingly strict, the main way to solve the problem is to achieve high-efficiency nitrogen and phosphorus removal. The discovery of denitrifying phosphorus-accumulating bacteria and the further research on the theory of denitrifying nitrogen-phosphorus removal provide new ideas and perspectives for the reform and innovation of the advanced treatment technology of simultaneous nitrogen and phosphorus removal. The denitrifying nitrogen and phosphorus removal technology overcomes the contradiction in the competition of carbon sources in the traditional treatment technologies and realizes the full utilization of the carbon source. Therefore, screening one denitrifying phosphorus-accumulating bacteria with high nitrogen and phosphorus removal capacity was significant, and the studies on its characteristics, key factors, and immobilization should be done. Applying it to the wastewater treatment process is an effective means to achieve effective control of nitrogen and phosphorus pollution. The research of this paper is divided into three parts: the screening and identification of strains, the study on the inoculation ratio of bacteria and the influence of key factors, the study ont the optimization of immobilization of bacteria. The first part: Using traditional microbiology technologycombined a series of screening tests, one strain screened, with the effect of simultaneous denitrification and dephosphorization, and purified, from the mature activated sludge in the sewage treatment plant. Moreover, the strain was identified as Acinetobacter using 16S rDNA microbial molecular technique. The second part: The influence of key factors of strain was studied in different initial pH, different electron acceptor types, different electron acceptor concentrations, and initial inoculation ratios. The effects of different initial pH, different electron acceptor types, and different electron acceptor concentrations on the nitrogen and phosphorus removal of strains were studied. The results showed that the phenomenon of denitrifying nitrogen and phosphorus removal more likely occurs in neutral and alkaline environments. Both nitrate and nitrite can act as electron acceptors, uptaking phosphorus under anoxic. However, the microbial effect in the nitrite electron acceptor system is stronger than in nitrate. Totally, in a certain range, higher electron acceptor concentration can promote hypoxia phosphorus absorption and phosphorus removal. While, it will inhibit phosphorus removal if the concentration is too high. In the different initial inoculation ratio studies, the initial inoculation ratios of microorganisms were set to 0%, 1%, 2%, 5%, 10% and 15%. The growth, phosphorus removal and nitrogen removal of the strains under different initial inoculation ratios were studied. According to the data, the optimal inoculum ratio was 2% for the initial inoculation of microorganisms, with the phosphate and nitrate removal rates 90% and 30.37%, with the initial concentrations of phosphate and nitrate of 25 mg/L and 60 mg/L, respectively. The third part: The immobilization optimization of the strains includes three parts of the carrier comparison, material optimization and performance testing of immobilized microbeads. Using sodium alginate and polyvinyl alcohol as immobilization agents, calcium silicate (CaSiO3) as immobilized carrier to do the experiments. Optimization experiments, with three factors and three levels, conducted by Box-Behnken in Design-Expert software. The results showed that the addition of calcium silicate could significantly improve immobilization performance. The denitrogenation and phosphorus removal efficiency of the microbeads can reach up to 75%. In addition, sodium alginate and polyvinyl alcohol in a certain concentration ratio range can increase the stability of the microbeads, as while as the denitrification and dephosphorization performance. The effects of sodium alginate, polyvinyl alcohol, and calcium silicate on the phosphate removal efficiency of immobilized beads were as follows: calcium silicate > polyvinyl alcohol > sodium alginate. The order of nitrogen removal was calcium silicate ≈ sodium alginate > polyvinyl alcohol.