分离高浓度污泥产酸发酵液的自生动态膜形成机制  

Formation Mechanism of Self-forming Dynamic Membrane During Separation of High-concentration Sewage Sludge Fermented for Acid Production

作　　者：黄帅[1] 刘宏波[1] 殷波[1] 马惠君[1] 符波[1] 刘和[1] 白洁[1] 

机构地区：[1]江南大学环境与土木工程学院环境生物技术研究室,无锡214122

出　　处：《环境科学》2015年第5期1720-1726,共7页Environmental Science

基　　金：国家自然科学基金项目(51208231);江苏省自然科学基金项目(BK20141112);江苏省自然科学基金项目(BK2014020607);江苏省太湖水环境综合治理科研项目(第七期专项资金)(JSZC-G2013-191)

摘　　要：采用自生生物动态膜分离高浓度污泥发酵液,研究了动态膜的形成过程及其对污泥发酵液的分离效果.结果表明,自生动态膜的形成过程受污泥浓度的影响较小,污泥浓度仅影响初始膜通量,不影响稳定时的膜通量.膜通量随着滤布孔径和搅拌速度的增大而增大.动态膜的形成过程符合死端过滤模型,分别由以下4个过程构成:先通过与膜基材孔径相似的污泥颗粒堵塞膜基材孔,其后在膜基材上形成单层污泥,进而在膜基材上形成多层污泥,最后,大颗粒污泥继续沉积到污泥层上.动态膜形成后,对污泥颗粒和溶解性COD(SCOD)的截留率分别为98%和28%,对挥发性脂肪酸(volatile fatty acids,VFAs)的渗透率在82%以上,胞外聚合物(extracellular polymeric substances,EPS)中的蛋白质是动态膜的主要成分.Self-forming dynamic membrane was used to separate high-concentration sludge fermentation liquid, and the formation mechanism and separation efficiency of dynamic membrane were investigated. The results indicated that the impact of sludge concentrations was negligible on the formation of dynamic membrane. Though membrane flux could be influenced by sludge concentration at the initial stage of membrane formation process, the influence was not obvious at the stable stage. Membrane flux was improved with increasing filter cloth pore size and stirring speeds. Moreover, the results indicated that the formation process of dynamic membrane followed the dead-end filtration model, which could be divided into four stages. Firstly, filter cloth pore was blocked by those sludge particles with the diameter similar to the pore size of filter cloth. Secondly, sludge particles formed monolayer sludge on the filter cloth. Thirdly, sludge particles formed multilayer sludge on the filter cloth. Finally, large sludge particles deposited onto the sludge layer. After formation of the dynamic membrane, the retention efficiency of sludge particles and SCOD could reach 98% and 28% , respectively, and the permeation efficiency of VFAs was over 82% . Proteins in EPS were the main component of the dynamic membrane.

关 键 词：自生动态膜 滤布 形成 过滤模型 污泥发酵液 膜分离 

分 类 号：X703[环境科学与工程—环境工程]