| 摘要 |
<p>1299977 Reverse osmosis module HYDRONAUTICS Inc 27 July 1970 [31 July 1969] 36250/70 Headings B1X and B2E A process for forming a tubular structure comprising a permeable membrane and a tubular support comprises introducing a casting liquid which comprises a film forming material and a carrier liquid into the tubular support in quantity exceeding the amount necessary to wet the entire interior wall surface of the support, draining excess casting liquid from the support and removing the carrier liquid from the film of casting liquid remaining on the support to cure the film by passing a column of liquid axially through the support. The casting liquid preferably comprises cellulose acetate, acetone and formamide; the carrier liquid is then removed to cure the membrane film by passing cold saline or cold water through the tubular support. Other casting liquid components are mentioned. A reverse osmosis module comprises (Fig. 2) parallel porous tubular supports 30, headers 32, 34 and 4-way valves 42, 52 for successive introduction and removal of casting liquid, curing liquid, hot water (to form an "active skin" on the membrane) and cold water, for preparation of the membrane film. In use, saline under pressure is supplied through line 40 and purer water is collected from the outside of tubes 30. When the module needs servicing, the membranes are dissolved away by a solvent and fresh membranes formed in the module as before.</p> |
