预涂动态膜强化超滤去除海水中有机物及其对膜污染的影响

发布时间：2018-12-28 09:36

【摘要】：以粉末活性炭和硅藻土为涂膜材料,在聚醚砜超滤膜表面形成预涂动态膜,考察了预涂动态膜对海水中有机物的去除效果和作用机制,通过比较分析直接超滤和预涂动态膜过滤海水前后膜表面亲疏水性、形貌结构、粗糙度及膜阻力分布的变化,探讨了活性炭和硅藻土预涂覆对超滤膜污染的影响.结果表明,预涂动态膜可提高超滤膜对海水中溶解有机碳(DOC)和UV_(254)的去除率,活性炭预涂动态膜对海水中DOC和UV_(254)的去除率较直接超滤分别提高11.2%和11.3%.硅藻土预涂膜主要利用超滤膜表面形成的硅藻土滤饼层强化海水中蛋白质类有机物的截留,活性炭对海水中小分子有机物的额外吸附导致海水过滤过程中活性炭预涂膜对有机物的去除效果优于硅藻土预涂膜.与直接超滤相比,预涂动态膜过滤海水后膜表面亲水性更好,膜表面粗糙度更低,膜过滤阻力也更小,活性炭预涂动态膜净化海水时膜过滤总阻力较直接超滤降低50.3%.利用涂膜材料在超滤膜表面形成的滤饼层将超滤膜与有机物进行了"隔离",避免了超滤膜与有机污染物直接接触,降低了小分子有机物在膜孔内的吸附堵塞,能够有效减缓超滤膜的不可逆污染.
[Abstract]:Using powdered activated carbon and diatomite as coating materials, a precoated dynamic membrane was formed on the surface of polyethersulfone ultrafiltration membrane. The removal effect and mechanism of pre-coated dynamic membrane on organic matter in seawater were investigated. By comparing and analyzing the changes of hydrophobicity, morphology, roughness and membrane resistance distribution of membrane before and after direct ultrafiltration and dynamic membrane filtration, the effects of pre-coating of activated carbon and diatomite on ultrafiltration membrane fouling were discussed. The results show that the removal rate of dissolved organic carbon (DOC) and UV_ (254) in seawater by UF membrane can be improved by precoating dynamic membrane. The removal rates of DOC and UV_ (254) in seawater by the dynamic membrane precoated with activated carbon were increased by 11.2% and 11.33%, respectively, compared with those of direct ultrafiltration. Diatomite precoated membrane mainly uses diatomite cake layer formed on the surface of ultrafiltration membrane to enhance the retention of protein organic matter in seawater. The removal of organic matter by activated carbon precoating is better than that by diatomite precoating during seawater filtration due to the additional adsorption of small molecule organic matter by activated carbon. Compared with direct ultrafiltration, the membrane surface hydrophilicity is better, the surface roughness is lower and the membrane filtration resistance is smaller. The total resistance of membrane filtration is reduced by 50.3% than that by direct ultrafiltration. The filter cake layer formed by coating material on the surface of ultrafiltration membrane is used to "isolate" the ultrafiltration membrane from organic matter, thus avoiding the direct contact between the ultrafiltration membrane and organic pollutants, and reducing the adsorption blockage of small molecular organic matter in the membrane pore. It can effectively reduce the irreversible pollution of ultrafiltration membrane.
【作者单位】：国家海洋局天津海水淡化与综合利用研究所;
【基金】：中央级公益性科研院所基本科研业务费专项资金项目(No.K-JBYWF-2015-T10,K-JBYWF-2016-T8) 海洋公益性行业科研专项项目(No.201405035)~~
【分类号】：P747

【相似文献】