Method of producing calcium carbonate from waste and by-products
US8603428B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | May 29, 2009 |
| Grant date | Dec 10, 2013 |
| Priority date | — |
| Expiry date | May 23, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P10/20
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention concerns a method for producing calcium carbonate containing the steps of extraction of alkaline industrial waste or by-products using as a first extraction solvent an aqueous solution of a salt formed from a weak acid and a weak base, whereby a vanadium-enriched first residue is allowed to settle and a calcium-rich first filtrate is formed, filtration, whereby the first filtrate is separated from the first residue, carbonation of the calcium-rich first filtrate using a carbonation gas, whereby calcium carbonate precipitates and a second filtrate is formed, and a second filtration, whereby the calcium carbonate is separated from the second filtrate. Further, the present invention concerns a method for extracting calcium carbonate and vanadium from alkaline industrial waste or by-products.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.