Water hammer reduces fouling during natural water ultrafiltration

WATER RESEARCH

卷:46

Article

Broens, F.²  Menne, D.¹  Blankert, B.³  Roesink, H. D. W.³  Futselaar, H.³  Lammertink, R. G. H.⁴  Wessling, M.^1,4 

[1] Rhein Westfal TH Aachen, Chem Proc Engn AVT CVT, D-52056 Aachen, Germany

[2] Convergence BV, NL-7418 EV Deventer, Netherlands

[3] Pentair X Flow BV, NL-7500 AS Enschede, Netherlands

[4] Univ Twente, Membrane Technol Grp, NL-7500 AE Enschede, Netherlands

关键词: Ultrafiltration;    Water hammer;    Fouling;   

DOI  :  10.1016/j.watres.2011.12.011

来源: Elsevier

【 摘 要 】

Today's ultrafiltration processes use permeate flow reversal to remove fouling deposits on the feed side of ultrafiltration membranes. We report an as effective method: the opening and rapid closing of a valve on the permeate side of an ultrafiltration module. The sudden valve closure generates pressure fluctuations due to fluid inertia and is commonly known as water hammer. Surface water was filtrated in hollow fiber ultrafiltration membranes with a small (5%) crossflow. Filtration experiments above sustainable flux levels (>125 l (m(2)h)(-1)) show that a periodic closure of a valve on the permeate side improves filtration performance as a consequence of reduced fouling. It was shown that this effect depends on flux and actuation frequency of the valve. The time period that the valve was closed proved to have no effect on filtration performance. The pressure fluctuations generated by the sudden stop in fluid motion due to the valve closure are responsible for the effect of fouling reduction. High frequency recording of the dynamic pressure evolution shows water hammer related pressure fluctuations to occur in the order of 0.1 bar. The pressure fluctuations were higher at higher fluxes (higher velocities) which is in agreement with the theory. They were also more effective at higher fluxes with respect to fouling mitigation. (C) 2011 Elsevier Ltd. All rights reserved.

【 授权许可】

Free