【作者】 方建文；

【导师】 刘建广；

【作者基本信息】 山东建筑大学 ， 市政工程， 2010， 硕士

【摘要】 生物流化池反应器(MBBR)是将传统活性污泥法和生物膜法相结合并引入流态化技术应用于水处理的一种新型生物膜水处理工艺。它具有处理效率高、容积负荷大、抗冲击能力强、设备紧凑占地少等优点。论文依托国家水体污染控制与治理科技重大专项(2008ZX07422003),以生物流化池反应器为研究对象,对人工模拟微污染水进行预处理研究,并对试验填料流化状态及流化池设计优化进行了研究。本论文首先以两级串联生物流化池反应器为研究对象,研究了流化池反应器自然挂膜和接种挂膜启动方式对比,并通过改变填充比、曝气强度和水力停留时间,考察不同条件下,MBBR对微污染水中有机物和氨氮的去除效果,提出了反应器最佳运行条件。试验结果表明：(1)两种挂膜方式启动过程中,在温度为25±5℃,从CODCr和氨氮的去除效果上看,MBBR1和MBBR2均在16天左右完成挂膜启动,不添加接种污泥不会造成挂膜启动时间的延长,采用自然挂膜生物膜相比接种挂膜厚；(2)常温下,水力停留时间2h,曝气强度5m3/m2时,处理效果最佳。氨氮和CODMn的去除率分别达到96%和70%,出水氨氮低于0.5mg/L,符合国家饮用水卫生标准要求；(3)低温条件下(T=6-10℃),CODMn和氨氮的去除效果明显下降。氨氮去除率由96%下降到70%,CODMn去除率由70%下降到40%。(4)低温条件下,反应器停止运行,重新启动需要6天左右。常温下,反应器的重新启动时间只需4天。为了进一步研究影响生物流化池反应器去除效果的因素,本文又对四种不同粒径悬浮填料流化状态,以及通过CFD软件模拟流化池内部气液两相流动优化流化池设计运行条件进行了研究。研究结果表明：(1)通过给填料配重,增大填料密度,可以有效改善填料流化效果；填料密度越接近于水,流化越容易。(2)流化实验结果表明,10mm柱状填料流化效果良好,所需曝气强度小,且在预处理微污染水实验中能有效去除有机物和氨氮,可以在水厂生物预处理工艺中推广使用。(3)可以考虑开发一种新型填料,填料密度选择在0.96-0.98g/cm3左右比较适合。(4)通过Fluent软件模拟曝气生物流化池中气液两相之间的相互作用。比较了不同纵横比、不同孔径、不同曝气速度流化池内气液两相的流速分布,对比数值模拟结果,发现曝气速度越大,曝气孔径越大,紊动强度和环流强度越大,有利于流化传质,提高去除率。(5)可以运用Fluent软件模拟反应器运行情况来解决设计和运行过程中遇到的问题。更多还原

【Abstract】 Moving Bed Biofilm Reactor (MBBR) is a new type of membrane water treatment process that combined with the traditional activated sludge,biofilm and fluidization technology. It has many advantages,such as high treatment effieiency, volumetric loading large, strong impactand the advantages of small footprint and so on. This paper depends on the National water pollution control and management technology major projects (2008ZX07422003), MBBR was used in advanced treatment of artificial simulation of micro-polluted water and the experimental filler fluid status and fluid design optimization Pool studied.First of all, the treatment effects of the MBBR were well studied. Two-stage biological fluidized reactor were used in series. The status of the two-stage biological fluidized reactor natural biofilm formation and inoculated biofilm formation, which was studied in order to help to accelerate the start-up. Through changes in reaction parameters such as the filling ratio, aeration intensity and hydraulic retention time, the carbonaceous and nitrogenous removal capacity of MBBR in the micro-polluted water was investigated. The best reactor operating condition which is based on the experimental results of the analysis. The results showed that:(1) Biofilm formation of two ways during startup,under the temperature of 25±5, from CODMn and NH4+-N removal efficiency point of view, MBBR1 and MBBR2 were completed in 16 days biofilm formation and start, Don’t add activated sludge will not cause biofilm formation and start time, compared with the two ways linked membrane biofilm thickness; (2) Under the conditions of ambient temperature, when HRT was 2h, aeration intensity was 5m3/m2, the removal of reactor reached the best. The removal rates of NH4+-N and CODMn reached 96% and 70%, and the effluent ammonia below 0.5mg/L, to meet standards for drinking water quality. (3) Under the conditions of low temperature(T=6-10℃), CODMn and NH4+-N removal efficiency decreased. NH4+-N removal rate decreased from 96% to 70%, CODMn removal rate decreased from 70% to 40%.(4) Under the conditions of low temperature, the reactor stops running, restart needs 6 days. Under the conditions of normal temperature, taking only 4 days to restart the reactor.To further study the impact of biological fluidized reactor pool removal of factors, this paper has suspended filler particle size on the four different streams of the state, and by CFD software to simulate the flow of pool within the gas-liquid two-phase flow to optimize the design and operation of pool conditions were studied. The results showed that:(1) To increasing weight of the packing, increasing packing density, can effectively improve the flow of packing effect; packing density is close to the water, streaming easier.(2) The flow of experimental results show that,10mm cylindrical packing fluid works well, it required low-intensity aeration, and can effectively remove CODMn and NH4+-N in the pretreatment experiments for micro-polluted water, it should be widespread used in water plant biological pretreatment. (3) Considering the development of a new packing, choose more suitable density of about 0.96-0.98g/cm3.(4) Fluent software to simulate aeration of Health through the logistics of the pool liquid two-phase interaction.Comparison of different aspect ratios, different diameter, different aeration tanks of gas and liquid flow rate of two-phase velocity distribution, compared to simulation results and found that the greater the aeration rate, aeration larger the circulation the greater the intensity of turbulence intensity and conducive to fluid mass transfer, increase the removal rate.(5) Simulated using Fluent software to encountered in the process to solve the operation of the reactor design and operation of the problems.更多还原