Immersed membrane filtration process
US6303035A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 1999 |
| Grant date | Oct 16, 2001 |
| Priority date | — |
| Expiry date | Oct 25, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W10/10
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A filtration process for filtering water with immersed microfiltration or ultrafiltration membranes in a batch mode includes repeated cycles comprising the steps of filling the tank to a level above the membranes, withdrawing permeate through the membranes, aerating the membranes to dislodge solids from the membranes and backwashing the membranes while draining the tank. The backwashing steps involve backwashings with a cleaning chemical interspersed with backwashings with permeate. The backwashings with a cleaning chemical follow a regimen of maintenance cleaning chosen to maintain acceptable permeability of the membranes or to reduce the rate of decline in permeability of membranes 24 over extended periods of time.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.