Method for removing mercury and selenium from sulfate-containing waste water
US10183879B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 13, 2014 |
| Grant date | Jan 22, 2019 |
| Priority date | — |
| Expiry date | Nov 26, 2035 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2209/06
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The invention is directed to a method for the removal of mercury and selenium from sulfate-containing waste water. The method may include the following steps: a) a mercury- and selenium-contaminated waste water with a known sulfate concentration is provided, b) barium sulfate (BaSO4) is precipitated from the provided waste water by the addition of a predefined amount of Ba2+ ions to the waste water, c) BaSO4 (if necessary together with other solids) is separated obtaining a low-solid waste water, d) the low-solid waste water is fed to an ion exchanger for the removal of mercury obtaining a waste water with a reduced mercury content, e) selenium and/or selenium compounds are removed from the waste water with the reduced mercury content and f) a sulfate-containing solution or solid is added to the waste water with a reduced selenium and/or selenium compound content in order to precipitate barium sulfate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.