吸附技术在水污染控制中的应用研究

发布时间：2018-07-24 12:32

【摘要】：水是人类生存不可缺少的重要自然资源,是社会可持续发展的重要物质保障。随着我国工业和农业的发展以及人口的增长,各行各业产生的大量废弃物和生活垃圾排入到水环境中,我国水环境污染形势十分严峻。根据2016年发布的《中国环境状况公报》,我国967个地表水国控断面(点位)水质监测结果显示,Ⅳ-劣Ⅴ类水质断面有343个,占35.5%。近年来严重影响人民生活与经济生产的水环境污染事件频频发生,造成巨大的人民健康损害和经济损失,社会影响也十分恶劣。据统计,我国在1996-2006年,共发生水污染公共卫生事件271起,累计受影响人口超过700万人,其中生物性污染、化学性污染和混合污染案例分别为171例、92例和8例,分别占63.1%、33.9%和3.0%。为了有效控制水环境的污染,国家先后制定了相关法律法规及标准等,同时大力开展水污染控制技术研究。当前水污染控制方法主要有物理法、化学法、物理化学法和生物法等。吸附技术以其操作简便、吸附材料可再生、便于控制与管理、对水质水温和水量变化具有较好的耐冲击负荷等优势在水污染控制中得到广泛的应用,但是由于很多用于水质处理的吸附材料存在吸附量不足、再生困难、对水质要求高等缺点,尚不能满足越来越繁重的水污染控制的现实需求。本研究主要针对水环境中的有机物、重金属和病毒污染等问题,利用吸附技术可吸附各种污染物的特点,以第三代活性炭产品?活性炭纤维(Activated Carbon Fiber,ACF)和自制载阳电荷吸附材料为研究对象,分别开展ACF对水中有机污染物苯胺的吸附效率研究;利用表面改性技术增加ACF表面含氧酸性基团,进行改性ACF吸附水中重金属污染物铅的研究;采用阳性电荷凝胶包被柱层层析硅胶的方法制备载阳电荷吸附材料用于吸附水中病毒,建立了一套富集大水样中病毒的装置及方法。1.ACF吸附水中苯胺:ACF是在碳纤维技术基础上发展形成的一种理想高效吸附新材料。ACF的比表面积大,其内部具有充足的微孔径。ACF以其吸附容量大、吸附速度快、处理量大且使用时间长等特点,在水质净化处理方面具有独特的优势。ACF对苯胺的吸附等温线符合弗兰德(Freundlich)吸附模式,在相同的苯胺平衡浓度时,发现303K比293K时的ACF投加量要大。另外,ACF吸附苯胺受p H值影响较大,随着溶液中p H值的升高,吸附效率呈明显上升趋势。在苯胺吸附过程中,应保持吸附环境的最佳p H值控制在7-8,这样可以充分发挥ACF对苯胺的吸附性能。2.表面改性ACF吸附水中重金属铅:利用硝酸对ACF进行改性处理,可显著提高ACF表面的羧基、内酯基、酚羟基等含氧酸性基团含量,含氧酸性基团含量可增加到1.846mmol/g。尤其是将羧基含量从0.012mmol/g增至0.848mmol/g,其增加量占基团总数增加量的78.87%。ACF表面酸性基团的增加可以为ACF吸附金属离子提供更多的吸附位点,其实际意义远比提高比表面积更为重要,且使p Hpzc从4.47减少至2.43。随着ACF表面酸性基团的大量增加,改性ACF对Pb2+吸附效率从45%左右增加至95%以上,并且快速吸附阶段的吸附速率提高了近3倍。3.载阳电荷吸附材料富集大水样中病毒:采用在60-100目的柱层层析硅胶表面包被上带阳性电荷的凝胶方法制备成载阳电荷吸附材料。扫描电镜结果可以看出载阳电荷吸附材料是在硅胶表面上包被上了一层凝胶,其平均粒径为271.59μm。将制备好的载阳电荷吸附材料装入内径为84 mm,高为40 cm有机玻璃过滤柱中,最终载阳电荷吸附材料的高度约为30 cm,将含有浓度为102 PFU/m L大肠杆菌噬菌体f2的100 L水样进行过滤,载阳电荷吸附材料对大肠杆菌噬菌体f2的回收率达到90%以上。分别测试了3倍营养肉汤、3%牛肉粉、甘氨酸、甘氨酸复合3倍营养肉汤和甘氨酸复合3%牛肉粉等5种洗脱液对载阳电荷吸附材料上吸附病毒的洗脱效果,结果显示只有甘氨酸回收率在60%左右,远低于其它4种洗脱液。通过分段检测各第一次浓缩液中大肠杆菌噬菌体f2的含量,发现只有甘氨酸复合3倍营养肉汤为洗脱液不存在脱尾现象,因此确定甘氨酸复合3倍营养肉汤为该方法的洗脱液。通过富集方法中各项参数的测试,确定了富集过程中最佳流速为500 m L/min;水样分别在p H值为5-9之间,温度在4-30℃之间时大肠杆菌噬菌体f2的回收率均很稳定,维持在90%以上;水中细菌浓度对大肠杆菌噬菌体f2影响较少。载阳电荷吸附材料富集方法与美国APHA推荐的1-MDS膜法比较具有对水质要求低和回收率高的优势。通过测试不同水体中病毒富集效果,发现载阳电荷吸附材料对不同地域的自来水、地表水和医院污水中的病毒均具有良好的富集去除效果。综上所述,本研究以吸附技术为基础,利用ACF、表面改性ACF以及自制载阳电荷吸附材料分别对水中苯胺、铅、病毒等典型污染物去除过程进行了研究,均取得了良好的效果。其中,改性前后的ACF对苯胺和铅均存在一个快速去除过程(5 min左右),达到平衡后的ACF对苯胺和铅的去除效率均在80%以上。自制载阳电荷吸附材料对大体积水样中的病毒具有较好的富集去除效果,当洗脱液为甘氨酸复合3倍营养肉汤、流速为500 m L/min、p H值为5-9之间、温度为4-30℃之间时,其回收率在90%以上。在下一步研究中将致力于把改性前后的ACF和载阳电荷吸附材料进行高效集成,研制出可同时用于控制水环境中的有机物、重金属和病毒的技术装备,面对日益复杂的水质污染状况,使其在水污染控制研究领域具有更为广泛的应用前景。
[Abstract]:Water is an important natural resource for human survival and an important material guarantee for the sustainable development of the society. With the development of China's industry and agriculture and the growth of the population, a large amount of waste and domestic waste from all walks of life are discharged into the water environment. The pollution situation of the water environment in China is very severe. According to the "China" published in 2016, "China" The Environmental Status Bulletin, the water quality monitoring results of 967 surface water state control section (point position) in China showed that there were 343 water quality sections of class IV inferior V, accounting for the frequent occurrence of water environmental pollution which seriously affected people's living and economic production in recent years, resulting in the great people's health damage and economic loss, and the social influence was very bad. According to the data, the social influence was very bad. According to the 35.5%. In the past 1996-2006 years, 271 public health incidents of water pollution have occurred in China, with a cumulative impact of more than 7 million people, including 171 cases of biological, chemical and mixed pollution, 92 and 8, respectively, 63.1%, 33.9% and 3.0%. to effectively control the pollution of the water environment. The state has formulated relevant laws and regulations successively. The current water pollution control methods are mainly physical, chemical, physical and biological, and so on. The adsorption technology is easy to operate, the adsorptive material is renewable, easy to control and manage, and has better impact load on water temperature and water quantity, and the water pollution is better in water pollution. It has been widely used in dyeing control, but due to the lack of adsorption capacity, difficult regeneration and high requirements for water quality, many adsorbents used in water treatment are still unable to meet the practical needs of more and more heavy water pollution control. This study is mainly aimed at the problems of organic matter, heavy metals and virus pollution in water environment, and so on. Adsorption technology can adsorb the characteristics of various pollutants. The study on the adsorption efficiency of aniline by ACF on the third generation activated carbon products (Activated Carbon Fiber, ACF) and the self-made positive charge adsorption materials of the organic pollutants in water, and the use of surface modification technology to increase the oxygen containing acid group on the surface of ACF, The study on the adsorption of heavy metal contaminants in water by modified ACF was studied. The positive charge gel package was prepared by column layer chromatography with silica gel to adsorb virus in water. A set of equipment for enriching the virus in large water samples and the method of adsorption of aniline in water.1.ACF were established. ACF was developed on the basis of carbon fiber technology. The ideal high efficiency adsorption new material.ACF has large specific surface area, and its interior has sufficient micropore diameter.ACF with its large adsorption capacity, fast adsorption speed, large amount of treatment and long use time. The adsorption isotherm of.ACF to aniline is in accordance with the Flander (Freundlich) adsorption model in the water purification treatment. When the equilibrium concentration of aniline was balanced, the amount of ACF added to 303K was larger than that of 293K. In addition, the ACF adsorbed aniline was greatly influenced by the value of P H. With the increase of P H value in the solution, the adsorption efficiency showed an obvious upward trend. In the process of aniline adsorption, the optimum P H value of the adsorption environment should be kept at 7-8, so that the adsorption properties of ACF to aniline could be fully played. 2. surface modified ACF adsorbed heavy metal lead in water: using nitric acid to modify ACF, the content of carboxyl group, lactone group and phenol hydroxyl group on ACF surface can be increased significantly, and the content of oxygen containing acid group can be increased to 1.846mmol/g., especially the content of carboxyl group from 0.012mmol/ g to 0.848mmol/g, and the increase of the amount of group is increased. The increase of the surface acidic group of the amount of 78.87%.ACF can provide more adsorption sites for the adsorption of metal ions on ACF, which is more important than improving the surface area. And the decrease of P Hpzc from 4.47 to 2.43. increases with the increase of the acid group of ACF surface, and the adsorption efficiency of the modified ACF increases from about 45% to over 95%, and is faster. The adsorption rate of the fast adsorption phase increased by nearly 3 times the.3. carrier adsorption material to enrich the virus in the large water sample. The positive charge adsorption material was prepared by the gel method of the 60-100 column layer chromatography on the silica gel bread with the positive charge. The scanning electron microscope results showed that the positive charge adsorption material was coated on the surface of the silica gel. A layer of gel was applied to the average particle size of 271.59 mu m.. The prepared positive charge adsorption material was loaded into the inner diameter of 84 mm, and the 40 cm organic glass filter column was high. The height of the positive charge adsorption material was about 30 cm, and the 100 L water containing 102 PFU/m L coliphage F2 was filtered and the positive charge adsorption material was carried. The recovery rate of Escherichia coli F2 reached more than 90%. The elution effects of 5 kinds of eluent on the adsorbed virus on the positive charge adsorbents were tested 3 times of nutrient broth, 3% beef powder, glycine, 3 times glycine complex and 3% beef powder, and the results showed that only the recovery rate of glycine was about 60%, far low. In the other 4 eluates, the content of Escherichia coli F2 in the first concentration liquid was detected by segmenting. It was found that only 3 times the glycine compound broth was not the tail of the eluant, so the glycine compound 3 times nutrient broth was determined as the eluent of the method. The optimum flow rate was 500 m L/min, the water sample was 5-9 at P H, and the recovery rate of Escherichia coli phage F2 was more stable than 90% when the temperature was 4-30. The concentration of bacteria in the water was less affected by the Escherichia coli phage F2. The enrichment method of the positive charge adsorption material was compared with the 1-MDS membrane method recommended by American APHA. It has the advantages of low water quality and high recovery rate. By testing the effect of virus enrichment in different water bodies, it is found that the positive charge adsorption material has good enrichment and removal effect on the virus in the water, surface water and hospital sewage in different regions. In summary, the study is based on the adsorption technology, using ACF, surface modified ACF The removal process of typical pollutants, such as aniline, lead and virus in water, was studied by the self-made positive charge adsorption material, respectively, and good results were obtained. Among them, there was a rapid removal process of aniline and lead (about 5 min) before and after the modified ACF, and the removal efficiency of ACF to aniline and lead after the balance was above 80%. The positive charge adsorption material has a good enrichment and removal effect on the virus in large volume water. When the eluate is 3 times the glycine compound meat soup, the flow rate is 500 m L/min, the P H value is between 5-9 and the temperature is 4-30 degrees C, the recovery rate is above 90%. The next step will be devoted to the modified ACF and the charge positive charge. The adsorption materials are integrated efficiently, and the technology and equipment of heavy metals and viruses which can be used to control the water environment at the same time are more widely used in the field of water pollution control.
【学位授予单位】：中国人民解放军军事医学科学院
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：X52;O647.3

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