粉末活性炭与MBR联合去除水源中微污染有机物

发布时间：2018-05-07 06:41

本文选题：微污染有机物 + 膜生物反应器　；参考：《哈尔滨工业大学》2013年硕士论文

【摘要】：饮用水的传统处理技术（混凝-沉淀-过滤-消毒）由于存在流程复杂、占地面积大以及不能有效去除微污染水源水中微量难降解有机物等诸多问题，难以满足新的饮用水水质标准要求。膜生物反应器（MBR）是一种高效的净水处理技术，向MBR投加粉末活性炭（PAC）可强化处理微污染水源水，尤其是提高对水中难降解有机物的去除能力。但由于水源水质不同，MBR在实际应用中表现出较大的性能差异，因而有必要对MBR系统去除各类污染物的性能和原理进行深入研究，以更好的指导实际应用。研究了MBR净化微污染水源水的特性。结果表明，MBR污泥和附着污染层的UF膜对氨氮、NOM和部分微量难降解有机物去除贡献较大，而曝气吹脱主要去除挥发性有机物。对MBR运行方式优化后，处理效果得到提升：对UV254、TOC的平均去除率均分别为53%和43%，对三氯乙烯、硝基苯、三氯酚的平均去除率均在63%以上。为提高MBR对微污染有机物的去除效果，考察向反应器中投加粉末活性炭形成PAC-MBR组合工艺的净水性能。粉末活性炭的投加方式分为单次投加和间隔多次投加，间隔投炭方式可稳定均衡的提升MBR对污染物的去除效果。间隔投加10mg/L活性炭的PAC-MBR工艺70天连续运行数据显示，组合工艺稳定运行期间净水性能良好，且显著优于MBR：对比未投炭MBR，组合工艺对UV254、TOC、氨氮的平均去除率分别提升27%、18%和41%；硝基苯和三氯酚平均去除率分别提升22%和21%。此外，投加PAC提高了组合工艺抗冲击负荷能力，系统稳定运行期间各污染物出水浓度均达到相应水质标准。同时考察了投加PAC对膜污染的影响。结果表明，投加PAC的系统膜清洗周期比单独MBR系统延长了1.6倍，达8.75d。三维荧光光谱分析结果表明，PAC-MBR系统对酪氨酸类蛋白质、色氨酸类蛋白质、富里酸、可溶性生物代谢物和腐殖酸这五类有机物的去除率均高于MBR，并可去除MBR所不能去除的腐殖酸和富里酸，去除率分别达到44%和45%。混合液污泥粒径分布显示，投加PAC后的污泥絮体平均粒径增大56%，更不易堵塞到膜孔中。SEM微观形貌观察进一步证明，传统MBR膜表面的污染层较为密实，基本无法分辨膜孔，而PAC-MBR系统的膜表面污染层较为疏松，膜孔清晰可辨。研究了PAC-MBR系统中微污染有机物去除途径。分析结果表明，，曝气吹脱对三氯乙烯的去除贡献最大，对三氯酚的去除能力较小，对硝基苯基本不能去除。粉末活性炭对硝基苯和三氯酚均有良好的吸附能力，吸附曲线分别符合准二级和准一级动力学方程，Langmuir模型预测的最大吸附容量分别为31.81mg/g和31.99mg/g。低进水量间歇式反应器法（FBR）测定不同污泥对硝基苯和三氯酚的最大比降解速率qmax证明，PAC-MBR污泥对微污染有机物的生物降解能力和抗冲击负荷能力均强于MBR污泥。Langmuir模型预测活性污泥对硝基苯和三氯酚的最大吸附量分别为0.06mg/g和0.30mg/g。通过对稳定运行的PAC-MBR进行物料平衡计算表明，三氯乙烯可由吹脱作用较彻底地去除；硝基苯主要通过生物降解（去除率58%）和PAC吸附（去除率29%）去除，三氯酚主要通过生物降解（去除率75%）和曝气吹脱（去除率16%）去除。
[Abstract]:The traditional treatment technology of drinking water (coagulating precipitation filtration disinfection) is difficult to meet the requirements of the new drinking water quality standard due to the complex process, large area of occupation and the inability to effectively remove the microbiodegradable organic matter in the micro polluted water. Membrane bioreactor (MBR) is a highly efficient water treatment technology, which is cast to MBR. The addition of powdered activated carbon (PAC) can strengthen the treatment of micro polluted water source water, especially to improve the ability to remove the refractory organic matter in water. However, because of the different water quality, the performance of MBR is different in practical application. Therefore, it is necessary to further study the performance and principle of removing all kinds of pollutants by MBR system in order to better guide it. Practical application.
The characteristics of MBR purification of micro polluted source water have been studied. The results show that the UF membrane of MBR sludge and the attached pollution layer contributes greatly to the removal of ammonia nitrogen, NOM and some microbiodegradable organic compounds, while aeration stripping mainly removes volatile organic compounds. After optimizing the operation mode of MBR, the treatment effect is improved: the average removal rates of UV254, TOC are both respectively. For 53% and 43%, the average removal rates of trichloroethylene, nitrobenzene and three chlorophenol were all above 63%.
In order to improve the effect of MBR on the removal of micro polluted organic matter, the water purification performance of PAC-MBR combination process was investigated by adding powder activated carbon into the reactor. The adding method of powdered activated carbon was divided into single dosage and interval dosing, and the interval cast method could steadily increase the removal effect of MBR on the pollutants. The activity of adding 10mg/L to the interval was added. The 70 day continuous operation data of the carbon PAC-MBR process showed that the water purification performance of the combined process was good during the stable operation and was significantly better than that of MBR: the average removal rate of UV254, TOC and ammonia nitrogen was raised by 27%, 18% and 41%, and the average removal rate of nitrobenzene and three chlorophenol was increased by 22% and 21%. respectively, and the PAC increased by PAC. The combined process has the ability to resist impact load, and the effluent concentration of each pollutant reaches the corresponding water quality standard during stable operation.
The effect of adding PAC on membrane fouling was also investigated. The results showed that the system membrane cleaning period of adding PAC was 1.6 times longer than that of the single MBR system. The results of 8.75d. three-dimensional fluorescence spectrum analysis showed that the PAC-MBR system had five kinds of organic compounds such as tyrosine protein, tryptophan, fulvic acid, soluble biological metabolite and humic acid. The removal rate is higher than that of MBR, and the removal of humic acid and fulvic acid can not be removed by MBR. The particle size distribution of the mixed liquid sludge with the removal rate of 44% and 45%. respectively shows that the average particle size of the sludge floc increases by 56% after the addition of PAC, and it is not easy to block the.SEM micromorphology of the membrane pores to prove that the pollution layer on the surface of the traditional MBR membrane is more dense. It is impossible to distinguish membrane pores, while the surface of PAC-MBR system is loose and the pore is clear.
The removal of Micropolluted organic matter in PAC-MBR system has been studied. The results show that the removal of trichloroethylene by aeration is the greatest contribution to the removal of trichloroethylene, the removal of three chlorophenol is less, and the nitrobenzene can not be removed basically. The powdered activated carbon has a good adsorption capacity for nitrobenzene and three chlorophenol, and the adsorption curves are in accordance with the quasi two grade and the quasi one respectively. The maximum adsorption capacity of the Langmuir model is 31.81mg/g and 31.99mg/g. low water intake batch reactor (FBR), respectively, to determine the maximum specific degradation rate Qmax of nitrobenzene and three chlorophenol in different sludge. The PAC-MBR sludge is stronger than MBR for the biodegradability and impact load of micro polluted organic matter. The maximum adsorption capacity of activated sludge for nitrobenzene and three chlorophenol was 0.06mg/g and 0.30mg/g. respectively by.Langmuir model.
The material balance calculation of stable running PAC-MBR shows that trichloroethylene can be removed thoroughly by blow off; nitrobenzene is removed mainly through biodegradation (removal rate 58%) and PAC adsorption (removal rate of 29%), and three chlorophenols are removed mainly through biodegradation (removal rate 75%) and aeration stripping (removal rate 16%).

【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】：2013
【分类号】：TU991.2

【参考文献】