动态膜-生物反应器中新型预涂剂的抗污染特性研究

Anti-fouling Characteristics of the Novel Precoating Reagent in Dynamic Membrane Bioreactor

对动态膜技术中的预涂剂进行了拓展研究,通过聚乙烯醇(PVA)与戊二醛(GA)的乳化交联制备新型预涂剂——PVA微球,分析交联反应机理,并通过PVA微球对产生膜污染主要物质EPS的吸附实验分析其抗污染特性.结果表明,乳化交联过程中主要发生的是半缩醛反应,PVA胶团的羟基数量实质上没有大量减少,PVA微球仍然保持良好的亲水性能,而且其表面呈现的电负性能够对活性污泥絮体产生静电排斥作用,PVA微球对活性污泥中蛋白质和多糖的吸附率稳定且较低,分别为0.543mg.g-1和0.694 mg.g-1,从微观上延缓了膜污染.预涂液中微球的粒径在1.14μm左右,其不同浓度的Zeta电位都小于-39mV,具有良好的稳定性,能够快速稳定地沉积在多孔底膜的表面和孔道内壁上,试验中采用SEM分析了PVA微球及其在工业滤布内部纤维丝上形成动态膜的表观形貌.

Further research was made on precoating reagents in dynamic membrane process, in which novel precoating reagent-polyvinyl alcohol microsphere （PVA-MS） was prepared through emulsive polymerization of PVA and glutaraldehyde （GA）. Furthermore, polymerization mechanism and anti-fouling characteristics through adsorption of membrane major fouling substances EPS upon PVA-MS were studied. The results showed that hemiacetals reaction played a major role in emulsive polymerization process, as the quantity of hydroxyl on PVA was decreased a little, PVA-MS surface behaved good hydrophilic, and the adsorption of protein and amylose upon PVA microsphere was stable and low, which was 0.543 mg·g^-1 and 0.694 mg·g^-1 respectively. In addition, PVA-MS surface behaved electronic negativity, which acted electrostatic repulsion to active sludge floc. Upon this characteristics and data, it was concluded that membrane fouling was delayed in microscopy structure. Diameter of PVA-MS in precoating liquid was about 1.14μm, and Zeta-potential of precoating liquid with different precoating reagent concentration was less than - 39 mV, which made PVA microsphere diffused and stable from each other, then sedimentate rapidly on porous support membrane surface and internal wall of hole path. Besides, the morphology of PVA-MS and dynamic membrane formed from PVA-MS on support membrane were observed through SEM.