Conversion of sea water by reverse osmosis
US4156645A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 16, 1977 |
| Grant date | May 29, 1979 |
| Priority date | — |
| Expiry date | Dec 16, 1997 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D61/026
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A process for recovery of fresh water by reverse osmosis from high salt content feed, such as sea water, comprises treating the feed water in an initial stage at relatively low pressure (between about 300 and 550 psi) employing a loose semipermeable membrane, to produce an intermediate product water containing one-fourth to one-half the TDS (total dissolved solids) content of the original feed water. The intermediate product water is treated in a subsequent stage also at a relatively low pressure (between about 300 and 550 psi) employing a tight semipermeable membrane, to produce a fresh product water containing less than 2,000 ppm TDS, and preferably a potable water containing less than 1,000 ppm TDS.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.