高强度、耐污染外压式聚砜超滤膜的研制
发布时间：2018-08-14 17:37
【摘要】：膜生物反应器(MBR)具有分离效率高、出水水质好、污泥浓度高、生化能力强等优势,是一种高效废水处理新技术。然而,目前MBR用超滤膜耐污染性较差,降低了膜分离性能,减少膜的使用寿命,增加了运行成本。本文针对膜生物反应器用超滤膜耐污染性差、膜强度不高等问题,分别选用有机添加剂、无机添加剂、有机/无机复合添加剂配制超滤膜铸膜液,通过改变铸膜液中添加剂的种类和含量改变超滤膜的耐污染性和机械强度,制备高强度、耐污染的超滤膜。本文选用聚砜(PSF)为膜材料,N,N-二甲基甲酰胺(DMAc)为有机溶剂,吐温80为表面活性剂,系统地研究了聚乙二醇(PEG)、聚乙烯吡咯烷酮(PVP)、氯化锂(LiCl)、聚乙烯吡咯烷酮/氯化锂等添加剂对聚砜超滤膜的结构与性能的影响,探讨了铸膜液中添加剂的种类和含量、聚砜含量、表面活性剂含量、搅拌温度和凝固浴温度等因素与超滤膜的耐污染性和机械强度的关系,研究、确定了适宜的高强度、耐污染聚砜超滤膜制备工艺,采用浸没沉淀相转化法制备了高强度、耐污染的聚砜中空纤维超滤膜。论文中采用实验室自制的膜性能评价装置、接触角测量仪对超滤膜的纯水通量、截留率和耐污染性进行了检测,用扫描电镜表征了膜的表面形态和断面结构。(1)系统研究了以聚乙二醇为添加剂制备聚砜超滤膜的各种影响因素,确定了其制备工艺参数:粘度0.58聚砜含量为14wt%,搅拌温度为80℃,聚乙二醇(PEG)400含量为15 wt%,吐温80含量为1 wt%,凝固浴温度为35℃。制备的超滤膜纯水通量为402.18 L/m2·h,截留率为91.76%,膜阻力增大系数为1.94,接触角为84.6°,分离性能和耐污染性能均优于不加添加剂的聚砜超滤膜。(2)系统研究了以聚乙烯吡咯烷酮为添加剂制备聚砜超滤膜的各种影响因素,确定了其制备工艺参数:粘度0.58聚砜含量为13 wt%,搅拌温度为70℃,聚乙烯吡咯烷酮(PVP)K30含量为6 wt%,凝固浴温度为30℃。制备的超滤膜纯水通量为902.07L/m2·h,截留率为91.18%,膜阻力增大系数为1.35,接触角为70.5°,分离性能和耐污染性能远优于不加添加剂的聚砜超滤膜。(3)系统研究了以氯化锂为添加剂制备聚砜超滤膜的各种影响因素,确定了其制备工艺参数:粘度0.58聚砜含量14 wt%,氯化锂含量为2.5 wt%,搅拌温度为80℃,凝固浴温度为30℃。制备的超滤膜纯水通量为480.09 L/m2·h,截留率为91.79%,膜阻力增大系数为2.16,接触角为83.4°,分离性能和耐污染性能均优于不加添加剂的聚砜超滤膜。(4)在聚乙烯吡咯烷酮和氯化锂的研究基础上,系统研究了以聚乙烯吡咯烷酮和氯化锂为添加剂制备聚砜超滤膜的各种影响因素,确定了其制备工艺参数:聚乙烯吡咯烷酮和氯化锂比例含量为9:1,聚乙烯吡咯烷酮和氯化锂复合添加剂总含量为6 wt%。制备的聚砜超滤膜纯水通量为1158.44 L/m2·h,截留率为86.22%,膜阻力增大系数为1.65,接触角为80.5°,耐污染性能虽然较以聚乙烯吡咯烷酮为添加剂的聚砜超滤膜稍差,但优于以聚乙二醇为添加剂的聚砜超滤膜、以氯化锂为添加剂的聚砜超滤膜和不加添加剂的聚砜超滤膜。(5)在前期研究基础上,研究、确定了以聚乙烯吡咯烷酮和氯化锂为复合添加剂的中空纤维超滤膜的制备工艺,并制备了高强度、耐污染的外压式聚砜中空纤维超滤膜,制备的外压式聚砜超滤膜纯水通量为305.47 L/m2·h,截留率为91.62%,断裂强力为873cN,断裂拉伸率为197%,膜阻力增大系数为1.86,接触角为81.4°,分离性能、机械性能和耐污染性能均优于无添加剂中空纤维聚砜超滤膜和商业化的内压式聚砜中空纤维超滤膜。
[Abstract]:Membrane bioreactor (MBR) has many advantages, such as high separation efficiency, good effluent quality, high sludge concentration and strong biochemical ability. It is a new high-efficiency wastewater treatment technology. However, at present, the MBR ultrafiltration membrane has poor pollution resistance, reduces the membrane separation performance, reduces the service life of the membrane and increases the operation cost. Ultrafiltration membranes were prepared with organic additives, inorganic additives and organic/inorganic composite additives respectively. By changing the type and content of additives in the casting solution, the anti-fouling and mechanical strength of the ultrafiltration membranes were changed to prepare high-strength and anti-fouling ultrafiltration membranes. The effects of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), lithium chloride (LiCl), polyvinylpyrrolidone/lithium chloride and other additives on the structure and properties of polysulfone ultrafiltration membranes were systematically studied. The types and contents of additives in casting solution were discussed. The relationship between the content of polysulfone, surfactant, stirring temperature and coagulation bath temperature and the fouling resistance and mechanical strength of the ultrafiltration membrane was studied. The suitable preparation process of high strength and fouling resistance polysulfone ultrafiltration membrane was determined. The high strength and fouling resistance polysulfone hollow fiber ultrafiltration membrane was prepared by immersion precipitation phase inversion method. The water flux, rejection rate and anti-fouling ability of the ultrafiltration membrane were measured by the contact angle meter. The surface morphology and cross-section structure of the membrane were characterized by scanning electron microscopy. (1) The factors affecting the preparation of polysulfone ultrafiltration membrane with polyethylene glycol as additive were studied systematically. The technological parameters are as follows: viscosity 0.58 polysulfone content is 14wt%, stirring temperature is 80%. PEG 400 content is 15wt%, Tween 80 content is 1wt%, coagulation bath temperature is 35%. Polysulfone Ultrafiltration Membrane without additives. (2) The factors affecting the preparation of polysulfone Ultrafiltration Membrane with polyvinylpyrrolidone as additive were studied systematically. The preparation parameters were determined as follows: viscosity 0.58, polysulfone content 13 wt%, stirring temperature 70%, polyvinylpyrrolidone (PVP) K30 content 6 wt%, coagulation bath temperature 30%. Pure water flux of membrane is 902.07 L/m2.h, rejection rate is 91.18%, membrane resistance coefficient is 1.35, contact angle is 70.5 degrees, separation performance and anti-fouling performance is much better than that of polysulfone ultrafiltration membrane without additives. (3) The factors affecting the preparation of polysulfone ultrafiltration membrane with lithium chloride as additive are studied systematically, and the preparation parameters are determined as follows: viscosity 0. 58 polysulfone content is 14 wt%, lithium chloride content is 2.5 wt%, stirring temperature is 80 C, coagulation bath temperature is 30 C. Pure water flux is 480.09 L/m2 h, rejection rate is 91.79%, membrane resistance coefficient is 2.16, contact angle is 83.4 Degree, separation performance and anti-fouling performance are better than those of polysulfone ultrafiltration membrane without additives. (4) In polyethylene pyrrole membrane Based on the study of pyrrolidone and lithium chloride, the factors affecting the preparation of polysulfone ultrafiltration membrane with polyvinylpyrrolidone and lithium chloride as additives were studied systematically. The preparation parameters were determined as follows: the ratio of polyvinylpyrrolidone to lithium chloride was 9:1, the total content of polyvinylpyrrolidone and lithium chloride as additives was 6 wt%. The purified water flux of polysulfone ultrafiltration membrane was 1158.44 L/m2.h, the rejection rate was 86.22%, the membrane resistance increased coefficient was 1.65, and the contact angle was 80.5 degrees. Although the fouling resistance of the membrane was slightly worse than that of polysulfone ultrafiltration membrane with polyethylene glycol as additive and lithium chloride as additive, it was better than that of polysulfone ultrafiltration membrane with polyethylene glycol as additive and polysulfone ultrafiltration with lithium chloride as additive. Polysulfone Ultrafiltration Membrane and Polysulfone Ultrafiltration Membrane without Additives. (5) On the basis of previous studies, the preparation process of hollow fiber Ultrafiltration Membrane with polyvinylpyrrolidone and lithium chloride as compound additives was determined, and the high strength and pollution-resistant hollow fiber Ultrafiltration Membrane with external pressure was prepared. 5.47 L/m2.h, the rejection rate is 91.62%, the breaking strength is 873 cN, the breaking elongation rate is 197%, the increase coefficient of membrane resistance is 1.86, the contact angle is 81.4 degrees. The separation performance, mechanical performance and anti-pollution performance are superior to those of hollow fiber polysulfone ultrafiltration membrane without additives and commercial hollow fiber polysulfone ultrafiltration membrane.
【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703
本文编号：2183609
[Abstract]:Membrane bioreactor (MBR) has many advantages, such as high separation efficiency, good effluent quality, high sludge concentration and strong biochemical ability. It is a new high-efficiency wastewater treatment technology. However, at present, the MBR ultrafiltration membrane has poor pollution resistance, reduces the membrane separation performance, reduces the service life of the membrane and increases the operation cost. Ultrafiltration membranes were prepared with organic additives, inorganic additives and organic/inorganic composite additives respectively. By changing the type and content of additives in the casting solution, the anti-fouling and mechanical strength of the ultrafiltration membranes were changed to prepare high-strength and anti-fouling ultrafiltration membranes. The effects of polyethylene glycol (PEG), polyvinylpyrrolidone (PVP), lithium chloride (LiCl), polyvinylpyrrolidone/lithium chloride and other additives on the structure and properties of polysulfone ultrafiltration membranes were systematically studied. The types and contents of additives in casting solution were discussed. The relationship between the content of polysulfone, surfactant, stirring temperature and coagulation bath temperature and the fouling resistance and mechanical strength of the ultrafiltration membrane was studied. The suitable preparation process of high strength and fouling resistance polysulfone ultrafiltration membrane was determined. The high strength and fouling resistance polysulfone hollow fiber ultrafiltration membrane was prepared by immersion precipitation phase inversion method. The water flux, rejection rate and anti-fouling ability of the ultrafiltration membrane were measured by the contact angle meter. The surface morphology and cross-section structure of the membrane were characterized by scanning electron microscopy. (1) The factors affecting the preparation of polysulfone ultrafiltration membrane with polyethylene glycol as additive were studied systematically. The technological parameters are as follows: viscosity 0.58 polysulfone content is 14wt%, stirring temperature is 80%. PEG 400 content is 15wt%, Tween 80 content is 1wt%, coagulation bath temperature is 35%. Polysulfone Ultrafiltration Membrane without additives. (2) The factors affecting the preparation of polysulfone Ultrafiltration Membrane with polyvinylpyrrolidone as additive were studied systematically. The preparation parameters were determined as follows: viscosity 0.58, polysulfone content 13 wt%, stirring temperature 70%, polyvinylpyrrolidone (PVP) K30 content 6 wt%, coagulation bath temperature 30%. Pure water flux of membrane is 902.07 L/m2.h, rejection rate is 91.18%, membrane resistance coefficient is 1.35, contact angle is 70.5 degrees, separation performance and anti-fouling performance is much better than that of polysulfone ultrafiltration membrane without additives. (3) The factors affecting the preparation of polysulfone ultrafiltration membrane with lithium chloride as additive are studied systematically, and the preparation parameters are determined as follows: viscosity 0. 58 polysulfone content is 14 wt%, lithium chloride content is 2.5 wt%, stirring temperature is 80 C, coagulation bath temperature is 30 C. Pure water flux is 480.09 L/m2 h, rejection rate is 91.79%, membrane resistance coefficient is 2.16, contact angle is 83.4 Degree, separation performance and anti-fouling performance are better than those of polysulfone ultrafiltration membrane without additives. (4) In polyethylene pyrrole membrane Based on the study of pyrrolidone and lithium chloride, the factors affecting the preparation of polysulfone ultrafiltration membrane with polyvinylpyrrolidone and lithium chloride as additives were studied systematically. The preparation parameters were determined as follows: the ratio of polyvinylpyrrolidone to lithium chloride was 9:1, the total content of polyvinylpyrrolidone and lithium chloride as additives was 6 wt%. The purified water flux of polysulfone ultrafiltration membrane was 1158.44 L/m2.h, the rejection rate was 86.22%, the membrane resistance increased coefficient was 1.65, and the contact angle was 80.5 degrees. Although the fouling resistance of the membrane was slightly worse than that of polysulfone ultrafiltration membrane with polyethylene glycol as additive and lithium chloride as additive, it was better than that of polysulfone ultrafiltration membrane with polyethylene glycol as additive and polysulfone ultrafiltration with lithium chloride as additive. Polysulfone Ultrafiltration Membrane and Polysulfone Ultrafiltration Membrane without Additives. (5) On the basis of previous studies, the preparation process of hollow fiber Ultrafiltration Membrane with polyvinylpyrrolidone and lithium chloride as compound additives was determined, and the high strength and pollution-resistant hollow fiber Ultrafiltration Membrane with external pressure was prepared. 5.47 L/m2.h, the rejection rate is 91.62%, the breaking strength is 873 cN, the breaking elongation rate is 197%, the increase coefficient of membrane resistance is 1.86, the contact angle is 81.4 degrees. The separation performance, mechanical performance and anti-pollution performance are superior to those of hollow fiber polysulfone ultrafiltration membrane without additives and commercial hollow fiber polysulfone ultrafiltration membrane.
【学位授予单位】：济南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X703
【参考文献】
相关硕士学位论文 前1条
1 陈佳丹;超滤膜的制备及其在菜籽油脱胶中的应用[D];武汉工业学院;2012年
，本文编号：2183609
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