【作者】 余建恒；

【导师】 周少奇；

【作者基本信息】 华南理工大学 ， 环境工程， 2010， 博士

【摘要】 随着现代化城市的迅速发展,城市垃圾和粪便已成为困扰城市的严重问题,其中的垃圾渗滤液和粪便污水更给环境带来很大的污染与危害。两类污水的氮和有机物浓度高,水质水量变化大,单独处理难度大,投资和运行管理费用高。若能将其与城市污水合并处理,利用城市污水对垃圾渗滤液、粪便污水的缓冲、稀释作用,实现垃圾渗滤液、粪便污水和城市污水同步处理同步达标,则具有非常重要的现实意义。然而垃圾渗滤液、粪便污水与城市污水合并处理将给城市污水处理厂带来严重的冲击负荷,往往出现脱氮效果不理想、生化系统不稳定、污泥产率大等突出问题,广州市大坦沙污水处理厂在长期接纳粪便污水和垃圾渗滤液的实际运行中发现两种污水瞬间混入时容易给污水厂带来较大的冲击负荷而导致氨氮、总氮出水不达标的现象。本文采用A²/O工艺中试装置,通过现场试验,研究了垃圾渗滤液、粪便污水与城市污水合并处理的适宜混合比、工艺参数和最佳工况并且探讨了投加填料后系统处理效果的变化。分别以混有垃圾渗滤液、粪便污水和既混有垃圾渗滤液又混有粪便污水的城市污水为研究对象,探讨了其适宜的混合比,通过单因素试验和正交试验研究系统的有机物去除和脱氮特性。结果表明:对三类污水脱氮和COD去除最主要的因素是水力停留时间;好氧池溶解氧浓度、污泥回流比、混合液回流比等因素也有较显著影响。粪便污水与城市污水合并处理的适宜的混合比为1:300,当水温为28-33℃,泥龄为20d时,在最优工况（水力停留时间9h、好氧池溶解氧浓度3mg/L、污泥回流比80%、混合液回流比200%）下运行,COD、NH₄⁺-N和TN平均去除率分别为88.0%、97.1%和69.9%。垃圾渗滤液与城市污水合并处理的适宜混合比为1:500,当水温为26-31℃,泥龄为20d时,在最优工况（水力停留时间11h、好氧池溶解氧浓度3mg/L、污泥回流比80%、混合液回流比200%）下运行,COD、NH₄⁺-N和TN平均去除率分别为77.4%、97.2%和62.4%。垃圾渗滤液、粪便污水与城市污水合并处理的适宜的混合比为0.4:1.5:400,当水温为16-27℃,泥龄为20d时,在最优工况（水力停留时间11h、好氧池溶解氧浓度3mg/L、污泥回流比80%、混合液回流比200%）下运行,COD、NH₄⁺-N和TN平均去除率分别为87.7%、97.3%和64.6%。不同混合污水出水浓度均满足《城镇污水处理厂污染物排放标准》（GB18918-2002）一级A标准。通过在好氧池投加悬浮填料形成A²/O—生物膜工艺,进行解决污水厂接纳粪便液和垃圾渗滤液的瞬间混入带来的冲击负荷的影响和传统A²/O工艺在生物脱氮除磷在泥龄方面的矛盾的研究。比较了两种新型填料的处理效果,研究了新型填料的挂膜,确定了填料的最佳投配比和最佳投配方式;考察了水力停留时间、混合液回流比和污泥回流比对该工艺处理该混合污水的脱氮除磷效果的影响;通过对泥龄的试验研究,解决脱氮与除磷在泥龄上的矛盾;在试验得出的适宜工况条件下研究该工艺处理该混合污水的同步脱氮除磷效果。研究表明:在好氧段中投加立体中空生物圆柱形悬浮填料比投加轻质多孔陶粒的运行效果好,通过闷曝方式20天左右,生物膜挂膜成功;填料的最佳投配比为20%;最佳投配方式为填料在好氧1池和好氧2池的体积比为1:3;系统在好氧池水力停留时间为5h、混合液回流比为120%和污泥回流比为60%下具有良好的脱氮除磷效果;控制泥龄为6d时能缓解脱氮和除磷在泥龄方面的矛盾;稳定运行一个月时间,系统对COD、氨氮、总氮和总磷具有高效稳定的去除效果,COD、氨氮、总氮和总磷的平均出水浓度分别为36.22 mg/L、0.3mg/L、12.9 mg/L和0.35 mg/L,满足国家排放标准一级A标准。通过16S rDNA克隆文库方法对AA/O-生物膜系统进行微生物群落的形态及多样性研究,获得如下结果:系统中含有丰富微生物菌群,存在多种与脱氮性能及与烷烃降解有关的菌种。好氧池2号池中的微生物菌群在种类与数量上均比前三个区域的要多,说明投加悬浮填料在一定程度上使该区域的微生物群落结构发生了变化,这种变化对系统更好地降解有机物和除氮起到了积极的作用。更多还原

【Abstract】 With the rapid development of modern cities, urban garbage and fecal sewage has become a big concern,The landfill leachate and fecal sewage are resulting in significant pollutions to the environments. These two types of sewage have high concentrations of nitrogen and organic matters, and the influent quality and quantity are high changable. There were many problems when each of them was treated separately, such as difficulty to treat with proper technologies, high costs for above-mentioned investment and operation management. It is a good option to treat the three kind of sewage with combination so that the fecal sewage and landfill leachate can be easily treated to meet the discharging standards of China by using the effect of cushion and dilution.However, the combined treatment will bring about serious impact on the impulse loading to the sewage treatment plant, it may lead to unsatisfactory of nitrogen removal, biochemical system instability, high sludge production rate, and the effluent water quality. These phenomena were discovered in Datansa Sewage Treatment Plant which had the capacity of 550000 m³/d to treat sewage waste water.Therefore, we designed an A²/O bio-reactor in pilot scale to perform in-site tests for studying the optimal volumetric ratio of landfill leachate, fecal and domestic sewage, the operational parameters and optimal working conditions in the A2/O process. The variation of treatment efficiencies by adding suspended carriers in the oxygen tank are also investigated and discussed.The domestic sewage was mixed with landfill leachate and fecal sewage respectively. The affective factors of nitrogen and organic matters removal through single factor experiment and orthogonal test were conducted. The results showed that HRT had significant effects on nitrogen removal and on COD removal in both case of influent sewage. DO had a remarkable effect on NH4+-N removal in the influent mixture of domestic sewage with leachate.R had a remarkable effect on TN removal in the influent mixture of the domestic sewage with fecal. Moreover, r had a remarkable effect on TN removal to the latter wastewater. Leachate and domestic sewage synchronous processing at the optimal operating conditions（HRT11h、DO3 mg/L、R80%、r200%）, the average removal efficiencies of COD、NH₄⁺-N and TN were 77.4%、97.2% and 62.4%,respectively. In case of fecal sewage and domestic sewage synchronous processing at the optimal operating conditions（HRT9h、DO3mg/L、R80%、r200%）, the average removal efficiencies of COD、NH₄⁺-N and TN were 88.0%、97.1% and 69.9%, respectively. In case of leachate, fecal and domestic sewage synchronous processing at the optimal operating conditions（HRT11h、DO3mg/L、R80%、r200%）, the average removal efficiencies of COD、NH₄⁺-N and TN were 87.7%、97.3% and 64.6%,respectively. The effluent concentrations of COD、NH₄⁺-N and TN in different mixed sewages could meet the discharging limits required by China Discharge Standard of pollutants for municipal wastewater treatment plant.The A²/O -biofilm process was conducted by adding suspended carriers to the oxygen tank of previous A²/O reactor. The objective was to solve the various disadvantage causing by the high organic loading of fecal sewage and landfill leachate as well as the contradiction of SRT between the denitrification and the phosphorus removal in A2/O process. The fuction and the effects of these two carriers were investigated , the optimal ratio and the operation parameters with the addition of the carriers were obtained. The influence of HRT on simultaneous denitrification and the phosphorus removal, the mixed-liquid return ratio and sludge return ratio were experimentally tested to solve the contradiction between the denitrification and the phosphorus removal.The results demonstrated that the dosage of suspended three-dimensional hollow cylindrical biological carrier in the aerobic tank was better than that dosed by lightweight porous ceramic in comparison with the effective operation. The bio-film was formed after 20 days of aeration performance. The optimal volumetric ratio of the carriers was 20%, the optimal volumetric ratio for carriers between the oxygen tank 1 and the oxygen tank 2 was 1:3. The system had a better removal efficiencies of nitrogen and phosphours in the case of the HRT was 5h, the mixed-liquid return ratio was 120% and the sludge return ratio was 60%. It can relieve the contradiction between the denitrification and the phosphorus removal under the condition of the sludge retention time to be 6 days. The system had high and stable removal efficiencies, the average concentrations of COD, NH₄⁺-N, TN, TP in the effluent were 36.22 mg/L, 0.3mg/L, 12.9 mg/L, and 0.35 mg/L, respectively. The main water quality achieved in the effluent can meet the level A dischaging limits of the China discharging standard （GB18918-2002）.By using the molecular biological methods, 16S rDNA, the morphology and diversity of microbial community in the A²/O-biofilm system were studied, the results obtained from the experiments showed that abundant microorganisms communities and many bacteria species performing for the nitrogen removal and the degradation of of alkanes were found in the system. The species of various microorganisms in aerobic zone 2 was more abundant than those in the first three zones of the bioreactor. As a result, the dosage of suspended filler into the aerobic zone 2 could change and improve the structure and function of the microbial communities in the system with better biodegradation of organic matters and biological nitrogen removal in the system being achieved.更多还原