【作者】 王志平；

【导师】 蔡伟民；

【作者基本信息】 哈尔滨工业大学 ， 环境工程， 2006， 博士

【摘要】 好氧颗粒污泥是上世纪末研究发现的一种用于废水处理的新型微生物聚集体,它是微生物在特定环境下自发凝聚、增殖而形成的结构紧密、沉降性能良好、生物协作性强的生物颗粒。由于其结构复杂,能够在同一个颗粒内同时保存多种氧环境与营养环境,为各种微生物提供良好的生长环境,因而具有多种代谢活性,是实现废水一体化处理的理想主体。本文是在前期成功培养出好氧异养颗粒污泥的基础上,通过提高氮负荷、控制水力停留时间及曝气强度促进硝化反硝化微生物在颗粒内的积累,培养出了具有良好脱氮活性的颗粒污泥,并对其脱氮特性及机理做了初步探讨。重点研究了脱氮颗粒污泥的培养、特性以及脱氮反应模式、传质特性、反应动力学、颗粒污泥内微生物组成及分布,其主要研究内容如下:依据前期好氧异养颗粒污泥的培养策略,分别以活性污泥(AS)、硝化污泥(NS)、好氧异养颗粒污泥(GS)为接种体通过提高氨氮负荷、优化曝气流量促进硝化反硝化微生物在颗粒污泥内的积累。经过120天的培养,三种系统内均成功培养出了具有较高脱氮活性的颗粒污泥,在反应运行周期为4h,有机负荷为1.6g/L·d,氨氮负荷为0.53g/L·d的条件下,各系统的COD去除率分别达95.70、96.04和96.55%,氨氮去除率分别达90.67、94.51和97.29%。IA分析表明,三种成熟颗粒污泥的平均粒径分别达到了1.88、2.37、2.26mm,相应的湿污泥密度达到了1.0156、1.0187和1.0262g/cm~3,从而使各系统内的污泥浓度达到了7.25、9.81和12.32g/L,SVI下降到了51.67、42.11和40.03ml/g,最大沉降速率分别达到了104.22、120.89和135m/h。此外,成熟颗粒污泥内的EPS含量明显提高,分别达到了55.31、47.34和53.95mg/L,而颗粒的比表面积达到了837.76、740.74和892.03m~2/m~3。对颗粒污泥反应器内基质降解的过程分析表明,循环周期内的氨氮去除可分为两个阶段,即富营养(COD去除)阶段的高速除碳脱氮和贫营养(硝化)阶段的慢速脱氮。在不同运行条件下,颗粒污泥表现出不同的脱氮特性,这表明颗粒污泥反应器运行中可能存在多种脱氮机制,实际运行时的表观脱氮速率是多种途径共同作用的结果。通过对脱氮颗粒污泥反应器的曝气强度、进水基质及水力停留时间的优化,得出三种颗粒污泥系统的最优曝气流量分别为0.75、1.25、1.0L/min;进水COD浓度在短期内可在800~2000mg/L随意变化,而进水氨氮浓度则在经更多还原

【Abstract】 Aerobic granulation was a process in which suspended biomass aggregate and form discrete well-defined granules spontaneously in aerobic systems. Aerobic granular sludge has been investigated since last century. As self-aggregated bio-particles by microorganisms under certain conditions, it has compact structure and good settling ability. Because of the mass transfer limit, there could be different kinds of oxygen and substrate conditions in the granules, which could be propitious to the proliferation of various microorganisms. Based on the successful cultivation of aerobic heterotrophic granular sludge, granules with well nitrogen removal were cultivated by adjusting the ammonium loading rate, aeration rate and hydraulic retention time, and the properties and mechanisms of nitrogen removal were investigated in this work. The main projects were focused on the cultivation of nitrogen removal granules, nitrogen removal process, optimization of the reaction process, mass transfer characteristics, reaction kinetics and microbiological components and structure.The main experimental results were listed as follows: According to the prophase work on the heterotrophic aerobic granules, activated sludge (AS), nitrified sludge (NS) and aerobic heterotrophic granular sludge (GS) were used as the inoculum respectively, and the adjustment of ammonium loading rate, aeration rate and hydraulic retention time were used to promote the accumulation of nitrifier-denitrifier bacteria. After 120 days operation, granules with well COD and nitrogen removal activity were successfully cultivated in all the three types of systems. The COD removal efficiencies of the three systems were 95.70、96.04、96.55% and the ammonium nitrogen removal efficiencies were 90.67、94.51、97.29% respectively, under the operation conditions of cycle period being 4h, organic loading rate being 1.6g/L·d and ammonium-nitrogen loading rate being 0.53g/L·d.IA results showed that mature granules in three systems had mean diameter being 1.88, 2.37 and 2.26mm respectively, and the maximum settling velocity of which were 104.22, 120.89 and 135.00m/h. The corresponding wet sludge density was 1.0156, 1.0187 and 1.0262g/cm~3, and the MLSS were 7.25, 9.81 and更多还原