臭氧-水解酸化污泥原位减量工艺同步脱氮收磷特性及机理研究

With the growing interests on the synchronization of sewage and sludge treatment, sludge reduction by ozone in-situ absorbed more and more attention for its advantages such as simple operation , easily implemented and no second pollution.But the high costs of running and bad performance of nitrogen and phosphorus removal limits the development of sludge ozontion further.In order to solve these problems,a new sludge reduction process that combines biological treatment process of Anaerobic-Anoxic-Oxicprocess(A2O) and sludge decomposition by ozone-hydrolysis was proposed.Based on the obserbvation of sludge solution and carbon，nitrogen and phosphorus releasing and the analyses of influencing factors,the optimal operation conditions of slduge dicomposation were found.In addition, the oxygen contained in exhaust gas from the ozone reactor was intrduing into the aeration pool as an oxygen source,which could solve the shortage of oxygen supply for biological treatment and cut the treatment costs. The performance of nitrogen and phosphorus removal simultaneous in the new process and the impact of supernate returning into biological treatment process which coming from sludge ozonation and phosphorus recovery as struvite at sidestream were investaged.According to the results,an optimize scheme for nitrogen removal and phosphorus recovery synchronization in the new sludge reduction process was proposed; Considering the changes of microbial activity, sludge yield, microbial community diversity and population dynamics analyzed by polymerase chain reaction-denaturing gradient gel electrophoresis(PCR-DGGE) at different operation conditions in system, the mechanism of sludge reduction in-situ was explored, which will provides the scientific basis and guide for the treatment and the reclamation of sewage and excess sludge.

污水、污泥同步处理是当前污水处理领域新兴的热点、难点问题，污泥原位减量技术为该问题的解决提供了有效途径，其中以臭氧氧化污泥原位减量工艺最具代表性。针对该工艺处理成本高、同步脱氮除磷效果不好等缺点，本研究采用臭氧-水解酸化技术联合溶胞，并与A2/O生物处理系统耦合构成新型污泥原位减量工艺，通过对污泥溶胞过程中碳系、氮系和磷系物质释放规律及其影响因素分析，优化污泥溶胞控制条件，并将臭氧尾气回收利用，降低处理成本；采用结晶鸟粪石法回收厌氧富磷污水和污泥中的磷，研究磷回收方法和优控条件，考察污泥溶解液、收磷上清液回流和臭氧尾气对系统同步脱氮除磷能力的影响及其优化调控机制，提出同步脱氮收磷污泥原位减量方案；利用聚合酶链式反应-变性梯度凝胶电泳技术分析不同运行条件下生物系统内微生物群落动态，结合污泥微生物活性和污泥产率变化特点，揭示污泥原位减量机理，为污水、污泥同步处理与资源化提供科学依据和方法指导。

水泥同治是目前研究的热点，污泥臭氧化原位减量技术为该问题的解决提供了新思路，但存在处理成本高、脱氮除磷效果不好等问题；而污泥水解酸化同样可以使细胞溶解，成本低廉，故本研究取水解酸化和臭氧溶胞之优点，将二者引入污水生物处理系统，构建臭氧—水解酸化—MUCT同步脱氮收磷污泥原位减量新工艺。.首先考察了低投量臭氧（0mg/gTS～100mg/gTS）对污泥水解酸化的影响，优化了臭氧-水解酸化溶胞方案。结果表明，臭氧能够加速污泥水解酸化进程，而水解酸化能够进一步使污泥溶解。温度和MLVSS/MLSS比例越高，VFA峰值出现越早;兼顾成本和水解酸化进度，最佳的污泥溶胞方案为：臭氧投量77.0mg/gSS~90.0mg/gSS，35℃，接种比例30%，停留时间3天。.污泥溶解液可以作为脱氮除磷的碳源，其回流对硝化、有机物降解和好氧吸磷没有影响，但有42.3%COD残留。将不同比例的污泥溶解液回流到MUCT缺氧段，结果发现污泥溶解液回流对COD、氨氮的去除没有影响，对总氮、总磷影响较大；当污泥溶解液回流比例为10%时污泥表观产率明显下降，污泥减量近65.5%。.为降低出水氮磷，采用自制的水合硅酸钙回收富磷污水中的磷。在pH值为8.0，吸附时间1.0h条件下，去除1mg的PO43-仅需250mg水合硅酸钙，磷去除率接近100%。.将磷回收技术引入生物处理系统，构建新型臭氧—水解酸化—MUCT同步脱氮收磷污泥原位减量工艺，考察了不同磷回收比例下系统的脱氮除磷效能。结果表明，磷回收比例为15%时脱氮除磷效果最佳。通过比较不同阶段新系统中的MLVSS/MLSS和比污泥脱氢酶活性（TTC-SDHA）发现，运行末期的污泥活性均略有降低。经聚合酶链式反应—变性梯度（PCR-DGCE）技术分析可知新系统中微生物多样性较好，各区均出现Candidatus-Accumulibacter 和 Dechlormonas反硝化聚磷优势菌。.