摘要 |
A method of cleaning a membrane filtration module (5) is disclosed. The module (5) includes at least one or more membranes (7) located in a feed-containing vessel (6) and extending longitudinally between vertically spaced upper and lower headers (8, 9) into which the ends of the membranes (7) are potted. The lower header (9) is not required in all cases and the membranes (7) may be suspended vertically from the upper header (8) only. The membranes (7) have a permeable wall which is subjected to a filtration operation wherein feed containing contaminant matter is applied to one side of the membrane wall and filtrate is withdrawn from the other side of the membrane wall. One or both of the upper and lower headers (8, 9) have one or more openings (10) therein. The method includes the steps of: suspending the filtration operation; performing a cleaning process on the membrane wall to dislodge contaminant matter from the membrane wall into liquid surrounding the mem brane: performing a sweep of the feed-containing vessel (6) substantially parallel to the longitudinally extending membranes (7) to remove the liquid containing the disloged contaminant matter, at least in part, through the openings (10) in the header (8, 9) or, where only the upper header (8) is used, through an opening (12) in the module, and then recommencing the filtration operation.
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