【作者】 王淦；

【导师】 彭永臻；

【作者基本信息】 北京工业大学 ， 环境工程， 2013， 博士

【摘要】 中国污水处理普遍存在“重量轻质，重厂轻网，重水轻泥”的问题，为了克服这些问题带来的后果，解决氧化沟污水处理厂提标升级和节能降耗的关键设备及技术问题，以及正确应对氧化沟污水厂污泥处理处置的问题，对氧化沟曝气设备倒伞表面曝气机、预处理沉砂系统和氧化沟污水厂污泥特性进行了深入的试验及模拟研究，以指导关键设备的产品开发与运行优化。针对国内城镇污水处理厂能耗普遍较高的实际状况，开展污水处理厂高效曝气关键设备倒伞型表面曝气机的研究开发及相关技术研究。利用试验筛选方法，研制出氧化沟工艺关键设备——高效倒伞表面曝气机；并对倒伞表曝机设备的充氧性能及水力学性能进行测试研究，借助MATLAB计算机软件对充氧性能进行数值模拟研究，采用CFD技术对水力学特性进行数值模拟研究，建立了倒伞表面曝气机充氧性能数学模型，并利用此模型进行产品的设计、运行管理的精确曝气控制。我国的城市污水中砂粒的含量普遍偏高，砂粒粒径分布结构也与国外具有明显不同，目前污水除砂系统基本都是国外引进产品或者是国外产品的复制品，砂粒去除效果欠佳，因此，需要在传统沉砂池设备的基础上，利用试验研究和模拟分析方法，研究开发出新型或改进的高效沉砂除砂系统及成套设备并优化沉砂池的运行。针对主要分布在中国黄河以南7个省46座污水处理厂的数据基础上，用统计概率分布方法，重点对中国南方地区氧化沟污水厂的污泥特性、产生原因、处理处置现状进行深入分析，结合欧盟污泥处理处置现状和未来发展趋势，对中国南方地区污泥处理处置技术的未来发展趋势进行预测，并给出应对策略。取得的主要创新性成果如下：（1）开发出新型高效的大功率倒伞型表面曝气机，最大动力效率达到2.73kgO₂/kWh（行业标准（JB/T10670-2006）为2.1kgO₂/kWh）。（2）建立了倒伞表面曝气机充氧性能数学模型，并以此作为产品开发和运行控制的核心指导技术。利用此模型发现倒伞型表面曝气机存在1个最佳动力效率工况点，1个次佳动力效率工况点和1个动力效率凹谷，最佳工况点叶轮浸没深度为283.5mm，叶轮转速为29.73r/m（线速度5.06m/s），该点的动力效率为2.73kgO₂/kWh，在设计运行中，应以此点为控制目标；并对倒伞型表面曝气机的运行控制提出与过去完全不同的控制方式，建议运行稳定在最佳工况点，如果工艺运行需要对曝气量进行调整，推荐维持最佳液位不变，仅采用转速调整进行曝气量的控制，针对本次开发的倒伞型表面曝气机，叶轮转速建议控制在27.27r/m（线速度4.64m/s）～32.88r/m（线速度5.59m/s）之间，此运行区间内输入功率变化范围在81.3kW～131.4kW之间，动力效率变化范围在2.50kgO₂/kWh～2.73kgO₂/kWh之间。（3）采用一种用于评价污水预处理阶段沉砂池除砂效果的测试方法——连续取样沉降法，辅助沉砂池数值模拟手段，对新开发的新型旋流沉砂池性能进行评价，指导产品优化设计与优化运行。发现新型沉砂池除砂效率随水量增加逐渐减小，并存在一个突然下降的拐点；存在一个最佳搅拌桨片转速值，使得该点除砂效率最大。连续取样沉降法测试稳定快捷，能够很好地反映实际沉砂池运行效果，有助于对沉砂池运行进行优化与改进；利用一气体流量计通过对曝气支管间气体流量差来监测曝气沉砂池支管中气量的大小，以控制各支管间的启闭来有效的调整曝气量大小，同时利用上述测试方法研究出影响曝气沉砂池除砂性能的因素HRT、进水流速和曝气强度与除砂率之间的相互关系，有助于对曝气沉砂池运行的优化管理。（4）采用统计概率分布方法，对氧化沟污水厂的污泥特性、产生原因、处理处置现状进行深入分析，结合欧盟污泥处理处置现状和未来发展趋势，对中国氧化沟污泥处理处置技术的未来发展趋势进行预测，并给出应对策略。发现我国氧化沟污水厂污泥特性：污水厂最大概率密度脱水污泥含水率为78.73%；挥发分偏低，为43.21%；污泥高位热值偏低，为9.16MJ/kg-DS；污泥重金属除个别污水厂超标外，其他均能满足我国城镇污水处理厂污泥处置系列标准中相对较严的《城镇污水处理厂污泥处置园林绿化用泥质》（GBT23486-2009）标准。我国氧化沟污水厂污泥适合农用等资源化利用；污泥处置不适合采用独立焚烧处理工艺，有条件可采用高干脱水后制作燃料工艺。更多还原

【Abstract】 “Look up to quantity and down on quality, up to plant and down on network, upto sewage treatment and down on sludge disposal” used to be a main thinking amongdecision makers in China. These have maken some problems in wastewater treatment.In order to solve these problems, upgrade the wastewater treatment plants with theprocess of Oxidation Ditches（OD） in water discharge quality, energy saving andsludge disposal. Our study is focused on surface aerator of OD, grit chamber andsludge treatment and disposal, so as to develop more efficient equipments and getoptimal operation.The aim of the study is to investigate the oxygen mass-transfer characteristics ofthe vertical shaft tubine surface arerator to upgrade its power efficiency. A new type ofhigh efficiency surface aerator was developed with methods of test and simulation. Anew model of oxygen transfer characteristics of the surface arerator was set up withaid of MATLAB and CFD simulator. The model was applied in equipment developing,optimal operating in prcise aeration.3patents were applied related to thesetechniques.The grit in wastewater is high in Chinese wastewater treatment plants （WWTPs）.The particle size distribution is deferent to that of foreign contry. In China, most ofgrit removal equipments were introduced from overseas or copied from that of foreigncontrys, so the girt removal efficiency is very low. The study on the girt chamber wasfocused on developing a new high grit removal efficiency chamber and operatingoptimized with methods of tests and simulation.Using Statistical probability distribution method, analyze sludge characteristics,reasons, treatment and disposal situations of the sludge from the oxidation ditcheswastewater treatment plants in southern China，comparative study of the treatmentand disposal situations and future development trends of the sludge in EuropeanUnion，forecast future development trends of the methods used for treatment and finaldisposal of sewage sludge in southern China, and give some proposals for the sludgemanagement.As the results, it has been found that：1) A new type of high efficiency surface aerator was developed with powerefficiency of2.73kgO₂/kWh，however, the benchmarking is2.1kgO₂/kWh. 2) A new model of oxygen transfer characteristics of the surface arerator was setup. The model can be applied in equipment developing, optimal operating in prciseaeration.With aid of this model, we found that: There is a maximum power efficiencypoint, a sub-maximum power efficiency point and a minimum power efficiency pointfor this type of surface aerator, the submergence is283.5mm and the rotational speedis29.73r/m at the maximum power efficiency point; This result shows that it shouldbe controlled at the maximum power efficiency point in operation, and should keepconstant depth of immersion at a range of rotational speed from27.27r/m to2.88r/mand input power from81.3kW to131.4kW for this aerator in some occasion so as toget high power efficiency in operation;The input power is101.5kW at the maximumpower efficiency point, and the maximum input power is131.4kW in high powerefficiency area.3) Used a new method—continue sampling settling method, with aid ofnumerical simulation, to evaluated the grit chamber system, so as to optimaldeveloping the equipment and operating the system.The results show: the grit removal rate of the rotational flow grit chamberdecreases with water flow increase, and exists a break point, exists a optimized bladerotating speed with maximum girt removal rate. Continue sampling settling method isstable and quick, can realy evaluate the efficiency of the grit chambar, help toopotimize the operation of the system. With the help of a kind of air flow meter, tometer the air flow of the branch pipes of the aeration grit chamber for controlling theair flow, so as to study the relationship between aeration intensity and grit removalrate, it has been found that it is helpful to optimal operating.4) Using Statistical probability distribution method, analyze sludgecharacteristics, reasons, treatment and disposal situations of the sludge from thewastewater treatment plants with process of oxidation ditches in southern China，forecast future development trends of the methods used for treatment and finaldisposal of sewage sludge in southern China, and give some proposals for the sludgemanagement.As the results, the characteristics of OD sludge has been found that：the watercontent of the sludge with maximum probability density is78.73%. Volatile matter ofthe sludge is low:43.21%. High heat value is low:9.169.16MJ/kg-DS. The content of heavy metals can meet the standards of “The disposal of sludge from municipalwastewater treatment plant-Sludge quality for afforestation in gardens or forests”（GBT23486-2009）. The sludge from OD plants is suit for agricultural use, and cannot be used for incineration, but can be used for fuel after deeply dewatered.更多还原