厌氧流化床微生物燃料电池处理煤化工废水

发布时间：2018-01-06 15:09

本文关键词：厌氧流化床微生物燃料电池处理煤化工废水　出处：《青岛科技大学》2017年硕士论文　论文类型：学位论文

【摘要】：能源节约和废水处理已经成为许多工厂面临的共同难题。焦化废水作为一种典型的、难降解的煤化工废水,其主要成分包括氰化物、氨氮、酚类、多环芳烃及杂环化合物等物质。据最新的机构调查显示,国内多数煤化工企业对焦化废水的处理效果不理想,生化出水COD和优先控制污染物的浓度往往难以满足国内工业废水的排放标准。微生物燃料电池作为一种新型的生物能源装置,能够在处理污水的同时产生电能。本课题研究将厌氧流化床(AFB)工艺同微生物燃料电池技术(MFC)相结合,对AFB-MFC处理焦化废水的产电性能及污水处理效果进行了研究。本文采用共沉淀法制备了修饰材料纳米Fe_3O_4,并对原石墨棒阳极进行了修饰改性。经交流阻抗和循环伏安测试表明Fe_3O_4修饰石墨棒阳极增强了电极表面传递电荷的能力,提高了阳极的动力学活性。Fe_3O_4修饰阳极后MFC的产电性能有了明显的提高,其最大输出电压和功率密度分别为243 mV和9.81 mW/m~2,分别比未修饰前的提高了23.4%和114%。在优化了电极材料的基础上,以焦化废水为基质,考察了进水浓度及直接驯化、梯度驯化和富集培养三种微生物驯化方式对AFB-MFC产电性能及焦化废水处理效果的影响。研究结果表明,污泥经梯度驯化后AFB-MFC的性能最佳,AFB-MFC获得的最大功率密度和COD去除率分别为10.95 mW/m~2和86.28%。以不同进水浓度(952、1528、2238、3419 mg/L)的焦化废水作为底物发电时,AFB-MFC获得的最大输出电压和功率密度随进水浓度的增加呈先增大后减小的趋势,当进水COD浓度为2238 mg/L时,MFC获得最大输出电压和功率密度分别为284.5mV和14.69 mW/m~2。另外,本实验结合液液萃取和GC/MS技术分析了焦化废水处理过程中有机物组成及降解特性。研究结果显示AFB-MFC对焦化废水有较好的处理效果,其中酚、苯、醇、杂环化合物与多环芳烃等物质充分降解,去除率分别为99.63%、97.6%、98.3%、95.75%和92.87%。同时采用GC-MS内标法准确分析了其中主要酚类的质量浓度,该分析方法检出限为2.48~5.50μg/L,平均加标回收率在72.6%~115.8%之间,相对标准偏差RSD≤11.28%,能够满足酚类有机物的测试要求。由中间产物甲基苯甲酸初步推断出在厌氧流化床微生物燃料电池中,甲酚首先羧化生成苯甲酸类物质再进一步氧化开环裂解。当苯酚、邻甲酚和2,4-二甲基苯酚的初始浓度分别为274.7、231.8和76.7 mg/L时,AFB-MFC对三种酚类的降解反应符合一级动力学,其速率常数K分别为0.06989、0.07641和0.08783h~(-1)。
[Abstract]:Energy saving and wastewater treatment has become a common problem facing many factories. The coking wastewater is a typical refractory wastewater, coal chemical industry, the main components including cyanide, ammonia, phenols, polycyclic aromatic hydrocarbons and heterocyclic compounds. According to the latest survey, the treatment effect of the majority of domestic coking wastewater coal chemical industry is not ideal, the effluent COD and priority pollutants concentration is often difficult to meet the domestic and industrial wastewater discharge standards. The microbial fuel cell as a bio energy device, at the same time in the treatment of sewage to generate electricity. The research of anaerobic fluidized bed (AFB) process with microbial fuel cell technology (MFC) the combination of treatment of coking wastewater by AFB-MFC electricity generation and wastewater treatment effect were studied. This paper uses the modified nanometer Fe_3O_4 was prepared by co precipitation method And, the original stone inker anodes were modified. The AC impedance and cyclic voltammetry tests showed that Fe_3O_4 modified graphite anode rod to enhance the ability of the electrode surface charge transfer, the electricity production of MFC.Fe_3O_4 modified anode kinetic activity the increase has been significantly improved, the maximum output voltage and power density respectively. 243 mV and 9.81 mW/m~2, respectively, was increased by 23.4% and 114%. in the optimization based on the electrode material, the coking wastewater as substrate, the effects of influent concentration and direct gradient domestication, domestication and enrichment effects of three microbial acclimation on the electricity production of AFB-MFC and coking wastewater treatment research. The results show that the sludge after domestication by gradient AFB-MFC AFB-MFC to obtain the best performance, the maximum power density and the removal rate of COD were 10.95 mW/m~2 and 86.28%. with different influent concentration (9 52152822383419 mg/L) of the coking wastewater as substrate power, AFB-MFC maximum output voltage and power density with the increase in influent concentration decreased, when the concentration of COD was 2238 mg/L, MFC maximum output voltage and power density were 284.5mV and 14.69 mW/m~2. in this experiment combined with liquid-liquid extraction GC/MS technology and analysis of organic matter during coking wastewater treatment and degradation characteristics. The results show that AFB-MFC has better treatment effect on coking wastewater including phenol, benzene, alcohol, heterocyclic compounds and polycyclic aromatic hydrocarbons and other substances to degradation, removal rates were 99.63%, 97.6%, 98.3%, 95.75% and 92.87%. at the same time, the accurate analysis the concentration of phenolic and GC-MS internal standard method, the analysis method of the detection limit is 2.48~5.50 g/L, the average recoveries between 72.6%~115.8%, relative standard The deviation of RSD is less than 11.28%, which can meet the test requirements of phenolic compounds. The intermediate product methyl benzoic acid is inferred in anaerobic fluidized bed microbial fuel cell, the first generation of cresol carboxylic benzoic acid compounds and further oxidation of the ring cleavage. When the initial concentration of phenol, o-cresol and 2,4- two methyl phenol were 274.7231.8 and 76.7 mg/L, the degradation reaction of AFB-MFC to three kinds of phenols with the first-order kinetics, the rate constants of K were 0.06989,0.07641 and 0.08783h~ (-1).

【学位授予单位】：青岛科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X78;TM911.45

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