Back-flushable spiral wound filter and methods of making and using same
US6755970B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 20, 2002 |
| Grant date | Jun 29, 2004 |
| Priority date | — |
| Expiry date | Mar 20, 2022 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2325/04
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A spiral wound membrane filtration element capable of being back-flushed has a permeate carrier sheet; a permeable membrane filter layer sheet adhesively bonded to the permeate carrier sheet, and a feed spacer sheet. The membrane filter layer sheet folds over the feed spacer so that the feed spacer sheet is sandwiched between two layers of the membrane filter layer sheet. The sandwich positions over the permeate carrier sheet such that the adhesive seal bonds the membrane filter layer sheet to the permeate carrier sheet. The permeate carrier sheet, the membrane filter layer sheet, and the feed spacer sheet are wrapped around a permeate collection tube. The filter element is cleaned by pressurizing the feed solution or by creating a vacuum in the permeate collection tube, and periodically introducing a pressurized back flush fluid into the permeate collection tube of the filtration element to back-flush the membrane, under a pressure and for a time sufficient to dislodge a substantial portion of the retained solids on the surface of the membrane. The membrane filter layer sheet is made by placing a casting a casting solution of a certain thickness on a passing support substrate havi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.