Backwash
US8268176B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 27, 2004 |
| Grant date | Sep 18, 2012 |
| Priority date | — |
| Expiry date | Aug 18, 2026 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2321/185
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method of backwashing a membrane filtration module (4), said module (4) including one or more membranes (5) located in a feed-containing vessel (3), the membranes (5) having 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operation wherein feed containing contaminant matter is applied to one side of the membrane wall and filtrate is withdrawn from the other side of the membrane wall, the method including: removing liquid from the feed-containing vessel (3) until the level of liquid in the feed-containing vessel (3) falls to a first level (L2) below an upper level of the membranes; suspending the filtration operation; performing a liquid backwash of the membrane wall until liquid level within the feed-containing vessel (3) rises to a second predetermined level (L1) above said first level; aerating the membrane surface with gas bubbles to dislodge fouling materials therefrom; performing a sweep or drain down of the feed-containing vessel (3) to remove the liquid containing the dislodged contaminant matter; and recommencing the filtration operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.