BAF-MBR组合工艺处理城镇污水效能及工艺优化控制

发布时间：2018-06-01 18:44

本文选题：BAF-MBR组合工艺 + 污水回用　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：水资源缺乏是影响人类文明发展的主要限制因素之一,我国水资源尤为缺乏。目前,我国对污水治理与回用的建设逐渐重视,对已建成的污水处理项目加强监督管理并进行提标改造,是提高处理水质至污水排放高标准与污水回用标准的主要途径。本课题即是在污水处理厂原有工艺的基础上,进行BAF-MBR组合工艺的开发与优化,力求在满足城镇污水排放一级A标准以及污水回用标准的前提下,对BAF-MBR组合系统进行运行优化并降低能耗。本课题的主要研究内容包括BAF-MBR组合系统的组装启动与运行效能研究、运行参数的影响及优化、系统的深度化学除磷技术研究。对前置BAF段采用复合式接种挂膜法挂膜,夏季启动耗时8 d,冬季耗时13 d;对后置MBR段,直接接种活性污泥进行驯化。BAF-MBR组合系统处理效果明显,具有一定的抗冲击负荷能力,处理出水水质稳定达标,同时能有效控制膜污染。在本试验中,BAF段最佳运行参数为:进水流量100 L/d、气水比2:1、回流比200%,此时,BAF-MBR组合系统出水中COD、氨氮、TN的平均浓度为:7.11 mg/L、0.23mg/L、8.85 mg/L,平均去除率分别为94%、98%、58%。针对组合系统同步化学除磷进行研究,除磷方案主要包括:前置BAF亚铁盐除磷、前置BAF铝盐除磷、后置MBR亚铁盐除磷和后置MBR铝盐除磷,这四种方案的最佳投药量分别为20 mg/L、30 mg/L、25 mg/L和25 mg/L,药耗成本分别为0.014元/t、0.036元/t、0.0175元/t和0.003元/t。前置BAF亚铁盐除磷对系统的处理效果及膜污染速率均没有影响,同时药耗成本较低;前置BAF铝盐除磷不利于系统对TN的去除效果,且加快了前置BAF滤料的堵塞速率;后置MBR亚铁盐除磷会加剧膜污染速率;后置MBR铝盐除磷虽然一定程度上能控制膜污染,但是其药耗成本较高,同时会导致后置MBR的剩余污泥脱水性能较差。若条件允许在组合系统前设置混凝沉淀池,最佳的除磷方式为前置BAF投亚铁盐除磷;若无法设置混凝沉淀池,需要进一步进行药耗与膜污染的成本对比分析。本课题指出BAF-MBR组合工艺的优越性,研究影响组合系统处理效果的各项因素并进行优化,探明了在本组合系统中利用亚铁盐、铝盐在不同投药点进行同步化学除磷时的影响规律。本课题的研究有利于提高污水处理程度,实现污水的资源化利用,对于城镇污水处理厂的提标改造提供了理论与技术指导。
[Abstract]:Lack of water resources is one of the main limiting factors affecting the development of human civilization, especially in our country. At present, our country pays more and more attention to the construction of sewage treatment and reuse. Strengthening the supervision and management of the sewage treatment project and upgrading the standard are the main ways to improve the quality of water treatment to the high standard of sewage discharge and the standard of wastewater reuse. On the basis of the original process of sewage treatment plant, this paper develops and optimizes the BAF-MBR combination process, and strives to meet the first class A standard for urban sewage discharge and the wastewater reuse standard. Optimize the operation of BAF-MBR system and reduce energy consumption. The main research contents of this paper include the assembly start-up and operation efficiency of BAF-MBR system, the influence and optimization of operation parameters, and the deep chemical phosphorus removal technology of the system. The composite inoculation membrane hanging method was used in the front BAF section, which took 8 days to start in summer and 13 days in winter. For the MBR section after inoculation, the treatment effect of direct inoculation activated sludge acclimation. BAF-MBR system was obvious, and it had certain ability of resisting shock load. The quality of treated effluent is stable and up to standard, and membrane fouling can be effectively controlled at the same time. In this experiment, the optimum operating parameters of BAF are as follows: influent flow rate 100 L / d, air-water ratio 2: 1, reflux ratio 200. At this time, the average concentration of NH3-N TN in the effluent of the BAF-MBR system is 7. 11 mg / L, 0.23 mg / L, 8.85 mg / L, and the average removal rate is 94 / 9898 / L and 5858 / L, respectively. In this paper, the synchronous chemical phosphorus removal in the combined system is studied. The phosphorus removal schemes mainly include: phosphorus removal by BAF ferrous salt, aluminum phosphorus removal by BAF aluminum salt, phosphorus removal by post-MBR ferrous salt, and phosphorus removal by post-MBR aluminum salt. The optimal dosages of these four schemes are 20 mg / L 30 mg / L and 25 mg / L, respectively, and the cost of drug consumption is 0.014 yuan / t 0.036 yuan / t 0.0175 yuan / t and 0.003 yuan / t respectively. The removal of phosphorus by BAF iron salt had no effect on the treatment efficiency and membrane fouling rate of the system, and the cost of charge was low, and the phosphorus removal of the prefabricated BAF aluminum salt was not conducive to the removal of TN, and the blocking rate of the pre-BAF filter media was accelerated. The dephosphorization rate of membrane was aggravated by the phosphorus removal of MBR ferrous salt, and the dewatering performance of residual sludge after MBR was poor, although the phosphorus removal by aluminum salt of MBR could control the membrane fouling to some extent, but the drug consumption cost was high. If the conditions permit the setting of coagulation sedimentation tank in front of the combined system, the best way of phosphorus removal is to put ferrous salt in the front of BAF to remove phosphorus; if the coagulation sedimentation tank cannot be set up, the cost comparison analysis of drug consumption and membrane fouling should be carried out further. This paper points out the superiority of BAF-MBR combination process, studies and optimizes the factors that affect the treatment effect of the combined system, and explores the influence law of using ferrous salt and aluminum salt in the process of simultaneous chemical phosphorus removal at different dosing points in the combination system. The research of this subject is helpful to improve the degree of sewage treatment, realize the utilization of sewage resources, and provide theoretical and technical guidance for the upgrading of municipal wastewater treatment plant.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703.1

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