【作者】 江帆；

【导师】 陈维平；

【作者基本信息】 华南理工大学 ， 材料加工工程， 2006， 博士

【摘要】 目前,河流水环境污染已十分严重。高效、低成本、机动灵活的河流水污染治理新技术和新装备的研究是环境工程的前沿和热点之一。本论文运用材料加工工程和环境工程学科交叉方法,从研究生物载体材质-结构的生物特性入手,构造高效的河流污水处理环境——转笼生物反应器,为污水处理提供新型水环境治理材料和高效河流水污染治理装备,具有十分重要的理论和实际意义。经过大量试验、分析及数值模拟,得到如下主要研究成果:（1）进行了大量生物载体挂膜试验研究,探讨了生物载体材质-结构的生物特性。研究发现,生物载体的挂膜性能与材质的主要成分有关,材质的多样性有利于提高生物载体的挂膜性能,载体混合的移动床的挂膜试验就表现出良好污水处理效果,这为载体混合使用、提高移动床处理效果、及载体设计中的材质搭配提供了参考。生物载体的结构以提供微生物容身的比表面积越大越好,同时,载体构造多连通结构能提高载体表面利用率,并有利于布气和获得较佳的表面剪切力,使生物载体挂膜性能良好。对动态环境下生物载体挂膜过程所受的力进行了详细地描述,采用附着动力学模型定量地分析生物载体挂膜效果。（2）实现了多相流和动网格的耦合计算,并对生物载体的流体力学特性行数值模拟计算,以此来评价生物载体空间结构合理性,两者具有较好的相关性,为生物载体空间结构评价及优化提供了便捷的手段。根据数值计算结果,设计了一种新型缠绕型悬浮生物载体,并进行污水处理试验,在移动床有效容积1.8L、水流量30mL/min、HRT为1h、曝气流量0.3L/min的情况下,COD_Cr、NH₃-N的去除率分别为79.5%、80.3%,优于同等条件下的多面空心球、鲍尔环、阶梯环、生物陶粒等生物载体,并具有良好的抗冲击负荷的能力。（3）根据河流水污染治理的特点,采用主动移动床的理念,构造高效河流污水处理环境——转笼生物反应器,初步探讨了其工作原理,估算了其启动液流速度,发现转笼生物反应器能在多数河流中被液流启动。进行了启动试验、运行参数优化试验、稳定运行试验研究,在优化参数条件:转笼周壁的开孔率为58%,内叶片长度为35mm,转笼转速为1.5r/min,曝气量为2 m³/h,污水流量1 m³/h,HRT为1.2h,悬浮生物载体为缠绕型悬浮生物载体的条件下,COD_Cr的平均去除率为86.9%,NH₃-N的平均去除率为87.6%。在基质去除率和容积去除负荷方面,均优于曝气生物滤池、移动床等生物反应器。（4）对转笼生物反应器的污水处理机理进行了深入研究,根据莫诺特方程导出转笼生物反应器的降解不同基质的动力学方程,并由动力学试验回归得到动力学方程中的反应速度常数,讨论了不同生物载体对反应速度常数的影响;根据反应器物料平衡原理,导出转笼生物反应器的初步设计计算模型,根据试验回归出模型常数,分析了不同生物载体对设计模型常数的影响,并进行试验验证,设计计算模型误差在15%以内,为转笼生物反应器的放大设计和实际应用提供理论依据。（5）实现了多相流与滑移网格的耦合计算,在此基础上,对转笼反应器流体力学特性进行数值模拟计算,工况计算结果与试验结果具有较好的相关性,能为转笼生物反应器结构评价和优化提供有效的手段。并进行了本文设计的转笼生物反应器结构的内部结构及外叶片的优化计算,得到具有良好的流体力学特性的转笼结构为:内叶片长度为0.15Rz、内叶片数目为10片、内叶片形状为正曲面,外叶片端面型线为样条曲线。更多还原

【Abstract】 The rivers are polluted severely, and are cried for treatment. The research on new treatment technology and new devices is one of the most important and hot problem in environment engineering. In this dissertation, the interdisciplinary method with material machining is applied, from study on the biological properties of bio-carriers’material and structure to construction of high-efficiency sewage treatment environment, which is cage-type bioreactor, the new sewage treatment material and high-efficiency sewage treatment devices are provided. Through large numbers of experiments, analysis and numerical simulation, the main results and conclusions are as follows:（1） The large numbers of bio-film experiments of bio-carriers are processed, and the biological properties of bio-carriers’material and structure are discussed. The results show that the bio-film properties of bio-carriers are related with main components of bio-carriers materials, material diversity is beneficial for enhance the bio-film properties of bio-carriers, and the moving bed with mixing bio-carriers gets strong effect of sewage treatment. These can provide a reference for mixture using of bio-carriers, enhancing effect of moving bed, material combination in bio-carriers design. The results indicate that the bio-carriers structure need provide high specific surface area for microbe inhabiting region, and multi-connected structure can improve utilization rate of bio-carriers surface, and be beneficial for gas distribution and obtain the suitable surface shear stress. These can improve the bio-carriers bio-film properties. The force under condition of dynamics sewage treatment is described in detail, and the quantity of bio-carriers bio-film is analyzed by using of microbe adhesion kinetics model.（2） The coupling computation of multi-phase and dynamics mesh is realized, and the hydrodynamics characteristics of bio-carriers are numerical simulated, and it is used for evaluating the rationality of bio-carriers structure, and the computation results are positive related with bio-film results of experiment. It is an efficient method for evaluation of bio-carriers space structure and optimization. According to the computation results, a new suspended bio-carriers, whose structure is wire-wound, is designed, and it is used to treat sewage, the experiment results show that the removal rates of COD_Cr and NH3-N are 79.5%, 80.3% respectively under condition of the effective volume with 1.8L, water flow with 30 mL/min, aeration with 0.3 L/min. These results are better than that of multi-face hollow sphere, pall ring, stage ring, bio-ceramic, and it has more stable to shock load.（3） According to the characteristic of rivers pollution control, based on the initiative moving bed concept, the cage-type suspended carriers bioreactor is developed, which constructs high-efficiency environment for rivers sewage treatment. Its mechanism of removing contamination is analyzed, and flow velocity, which just can drive the bioreactor to rotate, is computed. The start-up experiment, operation parameters optimum experiment, and operation experiment are processed, the results show that the cage-type bioreactor can high effective treat sewage. Under the condition that aperture porosity on cage wall is 58%, the length of inside laminae is 35mm, the carriers fill rates is 50%, the hydraulic retention time is 1.2 h, aeration flow is 2.5 m³/h, the sewage flow is 1 m³/h, rotation-cage rotated speed is 1.5 r/min, and the removal rates of COD_Cr and NH₃-N are 86.9% and 87.6% respectively. Comparing with biological aerated filter and moving bed, it can get high effect.（4） The sewage treatment mechanism of cage-type bioreactor is studied in depth, according to the Monod equation, the kinetics equations of and biodegradation are deducted. The reaction rates constants are obtained by kinetics experiment, and the influence of different bio-carriers is discussed. The preliminary design model of cage-type bioreactors is derived from material balance principles, and the model constants are obtained by experiments. This model is validated by experiment, and the errors are less than 15%, these models are reference for enlarged design and practical application of cage-type bioreactors.（5） The coupling computation of multi-phase and sliding mesh is realized, and the hydrodynamics characteristics of cage-type bioreactors is numerical simulated. The computation results are positive related with experiment results, so the technology with multi-phase and sliding mesh is an efficient method for evaluation of bio-carriers space structure and optimization, and the inside structure of cage-type bioreactors is optimized. The optimized inside structure with proper hydrodynamics characteristics is obtained, which the length of inside lamina is 0.15 Rz, the number of inside lamina is 10, the profile of inside lamina is positive curve surface, the profile of outside lamina is spline.更多还原