Water softener using nanofiltration to reclaim a portion of the regenerating solution
US9181110B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Nov 11, 2013 |
| Grant date | Nov 10, 2015 |
| Priority date | — |
| Expiry date | Feb 21, 2034 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2303/16
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A water softening system includes apparatus that recycles a substantial percentage of the solution used for regenerating the system. This system conventionally includes a brine tank and a softening tank through which hard water from a source passes during normal operation. During a regeneration mode, the solution of sodium or potassium ions in the brine tank passes through the softening tank acquiring hardness ions, and then through a nanofilter that passes a much higher proportion of the sodium or potassium ions than the hardness ions from a high pressure side to a low pressure side. The hardness ions flow from the upstream end of the nanofilter through an outlet and into a drain. The liquid passing through the nanofilter contains salt that returns to the brine tank for reuse. Concentration of sodium or potassium ions may be tested during a fast rinse portion of the regeneration cycle.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.