【作者】 杨国靖；

【导师】 李小明； 曾光明；

【作者基本信息】 湖南大学 ， 环境工程， 2005， 硕士

【摘要】 水环境污染的主要特征是水体的有机污染和富营养化,特别是以氮、磷等营养物质造成的水体富营养化已导致了水环境质量的严重恶化,因此以控制富营养化为目的的氮、磷去除已成为各国主要的奋斗目标,研究高效、经济的污水除磷脱氮工艺和方法也成为世界各国污水处理领域普遍关注的热点。 本课题立足于国内外好氧颗粒污泥和生物除磷脱氮研究的最新成果,以普通絮状活性污泥作为接种污泥,在序批式反应器中采用逐渐减少污泥沉降时间的方法造成选择压,培育出了好氧颗粒污泥。在成功培养好氧颗粒污泥的基础上,通过对SBR反应系统运行参数进行调控,深入研究了好氧颗粒污泥同步除磷脱氮的影响因素及去除效果,并对其微生物学机理进行了探讨。 实验结果表明,通过提高COD负荷,逐步减小沉降时间造成选择压,可促进颗粒污泥的形成和累积。成熟期的颗粒污泥形态完整、结构致密、表面光滑、外观呈橙黄色,为近似圆形或椭圆形小颗粒,粒径大多在0.5～1.0mm,污泥体积指数SVI为27.0ml/g,MLSS为6800mg/L。颗粒污泥具有良好的沉降性能、较高的生物相浓度、较好的水力强度,而且颗粒污泥中的微生物种群具有多样化,所形成的微生物生态系统更稳定,抗外界干扰及自身恢复调节能力较强。 为实现同步除磷脱氮,以好氧颗粒污泥为研究对象,通过对SBR反应系统运行参数进行调控,在温度为25℃、pH值为7～8,厌氧反应80～90min、好氧反应240min、曝气阶段的DO为1～2mg/L、SRT为20d的运行条件下进行了研究。该系统连续运行四个月的结果表明,系统处于稳态时好氧颗粒污泥对氮、磷和有机碳具有非常稳定的去除效果。当进水氨氮、磷和乙酸碳浓度分别为25～50mg/L,8～15mg/L和100～180mg/L,系统MLSS、MLVSS分别为7.0g/L、6.4g/L时,颗粒污泥对氨氮、总无机氮、磷、乙酸碳的平均去除率分别达到97.8%、89.7%、96.8%、98.8%。同时大量反硝化聚磷菌与硝化菌在颗粒污泥中共存并富集,反硝化聚磷菌占全部聚磷菌的比率达到73.1%。更为重要的是反硝化聚磷菌在吸磷的同时可以进行反硝化脱氮,利用其体内PHB的“一碳两用”来实现同步除磷脱氮,不仅解决了反硝化细菌和聚磷菌对碳源需要的矛盾,达到了节省废水中的有机碳源和节省能源的双重目的,而且减少了剩余污泥量,这对低C/N比废水的同步除磷脱氮是非常有利的,无疑会对污水生物除磷脱氮的工程实践产生深远影响。更多还原

【Abstract】 Eutrophication is a global problem, in which blooms of cyanobacteria and eukaryotic algae occur as a consequence of the breakdown of community homeostasis from continued pollution of oligotrophic aquatic bodies with nutrients like nitrogen (N) and phosphorus (P) at levels which exceed growth-limiting concentrations for these photosynthetic organisms and it has induced serious deterioration to the quality of water environment. Phosphorus and nitrogen removal from wastewater is an effective approach for prevention of eutrophication in closed water systems. With the development of water pollution control both internationally and domestically, it has become a hotspot to do the research on how to control the water bodies eutrophication caused by nitrogen and phosphorus, and how to remove efficiently the nitrogen and phosphorus as well as how to develop a special technics used for nitrogen and phosphorus removal, which are suitable to the situation of our country, economically and effectively.Based on the latest research findings on aerobic granular sludge and biological nitrogen and phosphorus removal in both domestic and abroad, aerobic granular sludge had been cultivated with the method of decreasing sludge sedimentation time gradually to produce selective pressure by using normal activated sludge as inoculating sludge in this paper. After successfully cultivating aerobic granular sludge, the parameters affectiong nitrogen and phosphorus removal were studied through adapting the operational conditions of SBR. And then the characteristic and mechanism of nitrogen and phosphorus removal by aerobic granular sludge were explored.The experimental results show that aerobic granular sludge is cultured in sequencing batch reactor(SBR) with decreasing the sludge sedimentation time and increasing COD loading rate resulting in the selective pressure. The aerobic granular sludge has a very compact and regular structure with a diameter of 0.5 to 1.0mm and a clear outer shape, the Sludge Volumetric Index (SVI) and the Mixed Liquid Suspended Solid (MLSS) are as high as 27.0ml/g and 6800mg/L, respectively. Compared to conventional activated sludge floes, aerobic granular sludge has a regular, dense and strong physical structure, good settling ability, high biomass retention, and the ability to withstand shock-loading rate.Simultaneous phoshporus and nitrogen removal was achieved by aerobic granular更多还原