旋转管式微滤污染膜的低压旋转再生技术及其特性

LOW PRESSURE ROTATING RENEW TECHNIQUE AND ITS CHARACTERISTICS FOR FOULED MEMBRANE IN ROTATING TUBULAR MEMBRANE SEPARATORS

提出了一项适合于旋转管式微滤污染膜的低压旋转再生新技术,并介绍了该技术在旋转管式微滤膜中的实施办法和实施过程;通过不同低压旋转再生条件下得到的再生膜在不同操作压力、静膜以及不同旋转状态下的衰减性能试验,证明了低压旋转再生技术的有效性;通过对再生过程的详细观察和流动特性分析,确认了低压旋转再生微滤污染膜技术的根源在于污染物受到旋转离心力、流体对膜表面的高速冲刷力以及低压旋转产生的空化对污染物的空蚀等多种机理的作用;最后归纳了旋转管式微滤膜低压旋转再生技术具有针对性、自限性、低振动性和多机理性等特性;低压旋转再生技术因其简单可行,在一定条件下可以成为反冲洗再生微滤污染膜的替代技术。

A new kind of technique is proposed to renew the fouled membrane in rotary tubular micro-filtration membrane separators, which can renew the fouled membrane by rotating the membrane under low pressure. This is called RRLP technique. The process to implement the RRLP technique is introduced in experimental system, and the RRLP is proved effective by comparing the jump of the curves of the permeate flux versus time under different operation pressure, static membrane and different rotational speeds of membrane. The roles to regenerate the polluted membrane are by means of the centrifugal force of the contamination, the shear stresses along the membrane surface and the cavitation caused by RRLP technique. Observing the process of RRLP and analyzing the dynamic characteristics can confirm all the roles. At last, the properties of the RRLP technique are concluded to be selectivity on the fouled membrane, self-restrictive, low-vibratility with multi-mechanism. The RRLP technique is possible to replace the backwash in regenerating the fouled micro-filtration mem- brane.