农村分散式污水处理中MBR工艺的运用,环境工程硕士论文.docx

农村分散式污水处理中MBR工艺的运用,环境工程硕士论文近年来，随着社会新农村建设的不断深切进入，农村基础设施以及整体环境发生了很大变化。同时，农村生活污水的处理问题不但不能妥善解决，而且变得越来越严重。农村生活污水属于间歇排放，水质和水量波动较大，污水中含的机物浓度较高；还存在较高比例的人和动物的粪便，氮和磷的含量较高，尤其是磷含量。由于污水长期直接排入水体，而环境容量特别有限，导致水体黑臭、富营养化特别严重，因而农村污水分散式处理的技术需求迫切。当前常用的农村污水分散式处理技术有人工湿地、氧化塘等生态化处理技术，但这些工艺存在维护管理复杂、处理效率低等问题，迫切需要新型稳定的工艺技术。而MBR作为一种新型技术，在污水处理方面具有处理效率高、出水稳定、耐冲击负荷能力强、污泥产量少等显着优点。但由于MBR技术在我们国家起步晚，早期受限于膜材料的价格和技术难度，故该工艺较少应用于农村污水处理。现如今随着膜材料与污水工艺的结合发展，膜组件的成本大幅降低，设备逐步实现自动化控制，MBR工艺的优点更为突出，适用于农村污水分散式处理。因而，本论文研究了MBR工艺在农村分散式污水处理中的应用，以推动农村污水治理技术的发展。 实验以MBR工艺为基础，讨论了曝气强度、混合液回流比、污泥浓度、PAC投加量的最优工况，通过对处理污水的动态实验研究，考察了不同工况下系统对COD、氨氮、总氮、总磷的去除效果、膜清洗技术对膜污染的控制以及MBR工艺应用的可行性，主要研究结果如下： 在系统调试运行稳定后，去除效果到达设计要求后，曝气强度控制在500 L/m2h时，COD和氨氮的去除率到达90%以上，且氨氮的去除效果最好；混合液回流比控制在200%时，TN的去除率到达75%以上，TP的去除率到达70%以上，去除效果最好；污泥浓度控制在6000 mg/L时，COD的去除率到达90%以上，TP的去除率到达65%以上，氨氮和总氮的去除率到达70%以上，且COD和总氮的去除效果最好；系统PAC投加量控制在20 mg/L时，能够一定程度上改善COD、氨氮、TP的去除效果。同时采用酸/碱结合30 min的Na OH 0.5%浸泡冲洗和30 min的0.5% HCl浸泡冲洗的清洗方式，膜通量恢复效果约可到达95%以上的水平。 结合实验研究结果，对MBR工艺在农村污水分散式处理中的可行性进行中试研究，结果表示清楚：该工艺对污水中污染物有很好的去除效果，出水平均水质中COD约为30 mg/L，氨氮约为1.50 mg/L，TN约为8.8 mg/L，TP约为0.29 mg/L，能够保证系统出水水质基本到达(农村生活污水处理排放标准DB44/2208-2022和(地表水环境质量标准GB3838-2002地表水类水的要求。另外，在最佳工况下，膜的TMP约需要25天增长到设计限值，然后采用酸/碱结合的清洗方式，能够有效恢复膜的浸透特性。 关键字：MBR工艺；农村生活污水；膜通量；污水处理；混凝沉淀。 ABSTRACT In recent years, with the in-depth development of the construction of new socialistcountryside, great changes have taken place in rural infrastructure and environment. At thesame time, the problem that rural domestic sewage can not be properly treated is becomingmore and more serious. Rural domestic sewage is a kind of intermittent discharge. Its waterquality and quantity fluctuate greatly, and the concentration of organic matter is relativelyhigh. It also contains high components of human and animal manure, especially the contentof nitrogen and phosphorus. Because the sewage is directly discharged into the water bodyfor a long time, and the environmental capacity is very limited, resulting in the water bodyblack odor, eutrophication is very serious, so the technical demand of rural sewagedecentralized treatment is urgent. At present, the commonly used rural sewage decentralizedtreatment technologies include artificial wetland, oxidation pond and other ecologicaltreatment technologies. However, these processes have complex maintenance andmanagement, low treatment efficiency and other problems, so new and stable technologiesare urgently needed. As a new technology, MBR has obvious advantages in sewagetreatment, such as high treatment efficiency, stable effluent, strong impact load resistance,and low sludge output. However, due to the late start of MBR technology in my country,early limited by the price and technical difficulty of membrane materials, the process israrely used in rural sewage treatment. Nowadays, with the development of the combinationof membrane materials and sewage technology, the cost of membrane components has beengreatly reduced, and the equipment has gradually been automatically controlled. Theadvantages of the MBR process are more prominent, and it is suitable for rural sewagedecentralized treatment. Therefore, this paper studies the application of MBR technology inrural decentralized sewage treatment to promote the development of rural sewage treatmenttechnology. Based on the MBR process, the experiment discussed the optimal working conditions ofaeration intensity, mixed liquid reflux ratio, sludge concentration, and PAC dosage. Throughdynamic experimental research on the treatment of sewage, the system s COD underdifferent working conditions was investigated, Ammonia nitrogen, total nitrogen, totalphosphorus removal effect, membrane cleaning technology to control membrane pollutionand the feasibility of MBR process application, the main research results are as follows: After the system commissioning and operation are stable and the removal effect meets the design requirements, when the aeration intensity is controlled at 500 L/m2h, the removalrate of COD and ammonia nitrogen reaches more than 90%, and the removal effect ofammonia nitrogen is the best; the reflux ratio of the mixed liquid is controlled at 200 %, theremoval rate of TN reaches more than 70%, the best removal effect; when the sludgeconcentration is controlled at 6000 mg/L, the removal rate of COD reaches more than 90%,the removal rate of ammonia nitrogen and total nitrogen reaches more than 70%, and CODAnd the total nitrogen removal effect is the best; when the system PAC dosage is controlledat 20 mg/L, it can improve the removal effect of COD, ammonia nitrogen and TP to a certainextent. At the same time, the cleaning method of acid/alkali combination (30 min Na OH0.5% immersion rinse and 30 min 0.5% HCl immersion rinse) is adopted, and the membraneflux recovery effect can reach about 95% or more. Combined with the experimental research results, a pilot study was conducted on thefeasibility of the MBR process in the decentralized treatment of rural sewage. The resultsshow that the process has a good removal effect on pollutants in sewage, and the averageCOD in the effluent is about 30 mg/L Ammonia nitrogen is about 1.50 mg/L, TN is about8.8 mg/L, TP is about 0.29 mg/L, which can ensure that the effluent quality of the systembasically meets the surface water category IV of Surface Water Environmental QualityStandard (GB3838-2002) Claim. In addition, under the best working conditions, the TMPof the membrane needs to be increased to the design limit in about 25 days, and then theacid/alkali combined cleaning method can effectively restore the permeability of themembrane. Keywords： MBR process；Rural domestic sewage；Membrane flux；Wastewater treatment；Coagulation and sedimentation 。 文章为硕士论文，如需全文请点击底部下载全文链接】 1.2、国内农村污水分散式处理的现在状况与技术分析 1.2.1、农村污水分散式处理的现在状况 1.2.2、农村污水分散式处理的技术分析 1 3、 MBR膜工艺及应用现在状况 1.3.1 、MBR工艺原理. 1.3.2 、MBR的技术优势 1.3.3 、MBR技术在国内外的研究与应用进展 1.4、研究意义及内容. 第二章 实验方式方法与结果. 2.1、实验目的. 2.2、实验装置与实验经过. 2.3、实验材料 2.4、实验分析方式方法与仪器设备 2.5、实验用水与接种污泥 2.5.1、实验用水 2.5.2、接种污泥 2.6、膜通量与膜清洗 2.7、实验操作参数. 2.8、参数变化的影响 2.8.1、曝气强度的影响 2.8.2、混合液回流比的影响 2.8.3、污泥浓度的影响 2.8.4 、PAC投加的影响. 2.8.5、污染物的去除效果 2.8.6、膜通量及清洗 2.9、本章小结 第三章 污水分散式处理技术的工程应用 3.1、工程大概情况 3.2、工程设计. 3.2.1、设计进、出水水质 3.2.2、工艺可行性分析 3.2.3、工艺流程， 3.2.4、工艺设计 3.3、运行效果 3.3.1 、COD的去除. 3.3.2、氨氮的去除. 3.3.3、总氮的去除. 3.3.4、总磷的去除. 3.3.5、膜通量及清洗 3.4、本章小结. 结 论 针对我们国家农村污水分散式处理的迫切需求，本论文对MBR工艺在污水分散式处理中的应用进行了研究，得出结论如下： 第一，MBR工艺的实验研究表示清楚，曝气强度、混合液回流比、污泥浓度、PAC投加量等参数的变化对污染物的去除效果都有影响。在曝气强度为300 L/m2h - 900 L/m2h时，COD的去除率为70% - 90%，氨氮的去除率为63% - 90%，华而不实曝气强度为500L/m2h时，COD和氨氮的去除率均能到达90%，处理效果最好；在混合液回流比为150%- 300%时，TN的去除率为50%-70%，华而不实混合液回流比为200%时，TN的去除率均能到达70%，处理效果最好；在污泥浓度为4000 mg/L - 10000 mg/L时，COD的去除率为76%-92%，氨氮的去除率为65% - 92%，TN的去除率为40% - 73%，华而不实污泥浓度为6000 mg/L，COD、氨氮和TN的去除率分别为92%、78%和73%，污染物去除的效果更好；在投加PA 20 mg/L后，与空白试验相比，COD的去除率从87%提升到92%，氨氮的去除率从87%提升到89.5%，TP的去除率从76%提升到84%，改善了COD、氨氮和TP的去除效果。 第二，MBR工艺膜清洗的实验中，三种清洗方式的比拟表示清楚，采用酸/碱结合的清洗方式比单独用酸、碱或水的清洗方式对膜污染的去除更有效，即酸/碱结合的清洗方式能更好的去除过滤阻力，恢复膜通量。 第三，MBR工艺用于农村污水处理的中试研究表示清楚，该工艺对污水中污染物有很好的去除效果，出水平均水质中COD约为30 mg/L，氨氮约为1.50 mg/L，TN约为8.8mg/L，TP约为0.29 mg/L，能够确保出水水质基本到达(农村生活污水处理排放标准DB44/2208-2022和(地表水环境质量标准GB3838-2002地表水IV类标准。另外，在最佳工况下，膜的TMP约需要25天增长到设计限值，然后采用酸/碱结合的清洗方式，能够有效恢复膜的浸透特性。 综上所述，MBR工艺作为农村污水分散式处理工艺，一方面能够确保出水水质优质稳定，另一方面该工艺属于较易实现装备化的先进技术，运营管理中调控也更为灵敏和稳定，可通过微机实现自动线上控制，使运行管理者的操作方式更为方便，更适宜于当代农村污水的分散处理，应用价值较好。 以下为参考文献.