A new insight into membrane fouling mechanism in submerged membrane bioreactor: osmotic pressure during cake layer filtration.
A new insight into membrane fouling mechanism in submerged membrane bioreactor: osmotic pressure during cake layer filtration.
复制标题
DOI：
10.1016/j.watres.2013.02.041
复制
发表时间：
2013-05
期刊：
影响因子：
12.8
通讯作者：
Meijia Zhang;Wei Peng;Jianrong Chen;Yiming He;L. Ding;Ai-Jun Wang;Hongjun Lin;H. Hong;Ye Zhang
中科院分区：
文献类型：
--
作者：
Meijia Zhang;Wei Peng;Jianrong Chen;Yiming He;L. Ding;Ai-Jun Wang;Hongjun Lin;H. Hong;Ye Zhang
膜表面形成的滤饼层的实验过滤阻力与通过Carman-Kozeny方程计算的水力阻力之间存在较大差距，表明SMBR系统中滤饼层过滤过程中存在一种新的膜污染机制：渗透压。然后提出了基于化学势差的渗透压模型。模型模拟表明，渗透压占总操作压力的主要部分，pH、施加压力和离子强度是渗透效果的关键决定因素。结果发现，渗透压随pH、施加压力和添加离子强度的变化与模型模拟的结果非常吻合，为渗透机制的真实发生和所提出模型的可行性提供了第一个直接证据。这些发现说明了渗透压在过滤阻力中的重要作用，并提高了对 SMBR 系统膜污染的基本认识。
Big gap between experimental filtration resistance of cake layer formed on membrane surface and the hydraulic resistance calculated through the Carman–Kozeny equation, suggested the existence of a new membrane fouling mechanism: osmotic pressure during cake layer filtration in SMBR system. An osmotic pressure model based on chemical potential difference was then proposed. Simulation of the model showed that osmotic pressure accounted for the major fraction of total operation pressure, and pH, applied pressure and ionic strength were the key determining factors for osmosis effect. It was found that, variations of osmotic pressure with pH, applied pressure and added ionic strength were well coincident with perditions of model's simulation, providing the first direct evidences of the real occurrence of osmosis mechanism and the feasibility of the proposed model. These findings illustrate the essential role of osmotic pressure in filtration resistance, and improve fundamental understanding on membrane fouling in SMBR systems.