【作者】 胡宏博；

【导师】 韩洪军；

【作者基本信息】 哈尔滨工业大学 ， 市政工程， 2011， 博士

【摘要】 随着我国城市化发展的加剧,污水处理厂大多需建于城市内部。目前我国建设的城市污水处理厂多采用活性污泥工艺,由于其占地面积过大,且运行时有臭味发出,对于建于城市内的污水处理厂,该工艺已不能满足此种需求。而且大多城市对于位于市内的污水处理厂要求其出水达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)中的一级A出水标准,一般的活性污泥法无法达到此要求,尤其是其对总氮的出水限制。厌氧好氧生物滤池组合工艺是结合了A/O生物脱氮工艺与曝气生物滤池工艺的特点设计而成的新型工艺。它既具有曝气生物滤池工艺占地面积小、管理方便、出水水质好、无臭味等特点,又具有A/O工艺对总氮高效去除的特点。本文重点对厌氧好氧生物滤池组合工艺处理城市污水的脱氮效能进行了深入研究,其中包含该工艺的挂膜启动方法、生物膜和反冲洗污泥的特性、脱氮效能的影响因素、低温时提高脱氮效能的方法、实际应用效能以及流体动力学和底物去除动力学等内容。本文的主要研究成果简述如下:对厌氧好氧生物滤池组合工艺的启动方法和启动阶段污染物的去除特性进行了研究。采用先间歇进水后连续进水,连续进水时采用逐渐增加流量和回流比的挂膜方法启动反应器,经过30d的培养,系统出水COD保持在40mg/L左右,氨氮保持在4mg/L左右,总氮保持在15mg/L左右,系统启动完成。系统研究了厌氧好氧生物滤池的工艺参数,溶解氧、反冲洗、回流比、温度、水力负荷、厌氧/好氧容积比等对该工艺脱氮效能的影响。实验结果表明,滤料层上部污水溶解氧控制在3.0～3.5mg/L、回流比控制在130%、厌氧/好氧容积比控制在1:1.5时,系统对污染物的去除效果达到最佳。水力负荷增加,系统的出水水质也随之恶化,但当水力负荷恢复到原值后系统短期内即能完全恢复其处理能力。小试反应器的反冲洗周期为5d(厌氧生物滤池)和10d(好氧生物滤池);反洗对厌氧和好氧生物滤池都具有较大影响,但在短时间(130～150min)内基本可恢复到反洗前水平。而温度降低时,硝化、反硝化和同步硝化反硝化作用都受到较大影响,其中低温对硝化作用受到影响最为严重。厌氧好氧生物滤池工艺中好氧滤池的同步硝化反硝化率较低,在上述最佳工况下为12.00%左右,溶解氧、反冲洗、回流比、温度、水力负荷、厌氧/好氧容积比等因素也都对好氧滤池的同步硝化反硝化率具有一定影响。系统进入稳定运行阶段后,在进水流量控制在8.5L/h、回流比控制在130%、溶解氧控制在3.0～3.5mg/L、水温在19～25℃时,对COD、氨氮、总氮都有较好的去除效能。对滤料上的生物膜量、生物相、滤料挂膜的微观结构等进行了分析。并对滤池的反冲洗污泥特性进行了研究,发现滤池的反冲洗污泥对氨氮有一定的吸附作用,好氧滤池的反洗泥吸附值要高于厌氧滤池的反洗泥吸附值,反洗污泥活性对反洗污泥的对氨氮的吸附能力影响较小,金属盐混凝剂对反洗污泥的氨氮吸附能力影响也较小。温度的降低对系统脱氮性能有很大影响。低温下,可以通过适当的增加溶解氧浓度(提高到4.0mg/L)和回流比(提高到150%)及延长生物滤池的反冲洗周期(好氧滤池提高至10d,厌氧滤池提高至17d)来提高系统的脱氮效能。同时应用这三种优化方法对系统脱氮效能的提高更加显著,系统出水氨氮平均浓度可达到7.70mg/L,总氮平均浓度可达到15.25mg/L。将厌氧好氧生物滤池组合工艺应用于实际工程项目,通过现场实验对在调试运行中出现的问题查找了原因并提出了解决方案;并对实际工程中氮的转换途径及效能进行了实验分析,发现反冲洗污泥对氨氮的吸附可以达到7.22%,硝化率达72.30%,反硝化率达46.97%,同步硝化反硝化率达13.65%。无论常温或低温,工程项目处理后出水均可达到《城镇污水处理厂污染物排放标准》(GB 18918-2002)中一级A出水标准。以生物滤池堵塞模型和均质滤料毛细管模型为基础建立了厌氧好氧生物滤池的流体动力学模型;以Monod方程和微元法为基础建立了厌氧好氧生物滤池的底物去除动力学模型;并对建立的模型进行了模拟仿真和验证。仿真值与实验实测值的对比结果表明模型模拟仿真的效果较好。更多还原

【Abstract】 With the urbanization intensifies in China, many municipal sewage treatment plants need to built inside the city. Most of the municipal sewage treatment plants built in China was adopted the activated sludge process. Activated sludge process was not suitable the municipal sewage treatment plants which need to built inside the city,because its area is too big and stink when running out. The effluent was demand to meet the National discharge standard of level 1-A (GB 18918-2002) in china for many municipal sewage treatment plants which need to built inside the city. It is impossible to reach for the general activated sludge process, especially its total nitrogen effluent limitations.Anaerobic-oxic biological filter conbination process was designed combined with the advantages of A/O biodenitrification technology and biological aerated filters. Its area is small, management is convenient, effluent is high standards, no odor and so on which was similar with biological aerated filters; it had a high removal efficiency to total nitrogen which was similar with A/O biodenitrification technology. The removal characteristics of anaerobic-oxic biological filter conbination process for municipal sewage treatment were in-depth studied in this paper, such as cultivation and acclimation of biofilm, the characteristics of biofilm and backwash sludge, efficiency factors of nitrogen removal, preparation of new filter, application efficiency of the process, fluid dynamics and substrate removal dynamics research. The main conclusion briefly described as follows:At first, the startup method and removal characteristics of pollutant in startup stage have been studied. The method of startup of intermittence inflow at first then continuous inflow, gradually increase the flow and reflux ratio was adopted. The effluent of the system achieved COD about 40mg/L, ammonia nitrogen about 4mg/L, total nitrogen about 15mg/L after 30days of cultivation.Then, the process parameters of anaerobic-oxic biological filter conbination process were systematic studied, such as DO, backwash, reflux ratio, temperature, hydraulicload, anoxia /aerobic volumetric ratio,and so on. Results were shown that: The removal efficiency of system to pollutants achieved the best, when the DO was controlled in 3.0~3.5mg/L, the reflux ratio was controlled in 130% and the anoxia /aerobic volumetric ratio was controlled in 1:1.5.When the hydraulicload was increased, the pollutants of effluent was increased.When the hydraulicload recovered, the pollutants of effluent would recovered in short time.The backwash cycle was 5 days (anaerobic biological filter) and 10 days(aerobic biological filter) in reactor test. Backwash had a great influence to both aerobic biological filter and anaerobic biological filter. But it could be basic recovery the level before backwash in a short time (130~150 minutes).When the temperature droped, the nitrification, denitrification and simultaneous nitrification denitrification were all had great influence, and the most heavily influence of low temperature was nitrification.The SND rate is low in anaerobic-oxic biological filter conbination process.It reached about 12.00% in the best condition taking above. DO, backwash, reflux ratio, temperature, hydraulicload and anoxia /aerobic volumetric ratio all had influence on SND. It has good removal efficiency for COD, ammonia nitrogen and total nitrogen in the system under the process conditions like that water flow 8.5L/h, eflux ratio 130%, dissolved oxygen 3.0~3.5mg/L and water temperature 19~25℃.The characteristics of biofilm and backwash sludge were studied. The biological membrane and biological phaser, microstructure of filter were analyzed. When the characteristics of backwash sludge were studied, the ability of adsorb ammonia nitrogen was found. The adsorption property of backwash sludge in aerobic filter was stronger than that in anaerobic filter. The liveness of backwash sludge had little influence to the adsorption of ammonia nitrogen. Metal salt coagulants had little influence to the adsorption of ammonia nitrogen,too.Temperature had a great influence to the performance of nitrogen removal. Improve DO (increased to 4.0mg/L), improve reflux ratio (increased to 150%) properly and extended backwash period (anaerobic filter 10d and oxic filter 17d) could improve the denitrification efficiency of system when the temperature was low. Using the three methods meanwhile in low temperature had even more significant improvement role to nitrogen removal. The effluent of the system achieved ammonia nitrogen about 7.70mg/L, total nitrogen about 15.25mg/L at that time.The anaerobic-oxic biological filter conbination process was applied in practical engineering project. Problem, reason and solution in operation period in application project were researched by the field experiment.Conversion ways and efficiency for nitrogen in practical engineering project were researched. The efficiency of adsorption of ammonia by backwash sludge was about 7.22%, the efficiency of nitrification in aerobic biological filter was about 72.30%, the efficiency of denitrification in anaerobic biological filter was about 46.97% and the efficiency of SND in aerobic biological filter was about 13.65% in practical engineering project.This technology had high removal rate of nitrogen to the municipal sewage. The effluent could meet the National discharge standard of level 1-A (GB 18918-2002) in china whatever low or normal temperature.At last, a fluid dynamics model was built based on filtering jams model in biological filter and capillary model in biological filter. The substrate removal dynamics models were built based on Monod equation and micro element method. And the models were analyzed and simulated.更多还原