Systems and methods to treat flue gas desulfurization waste to produce ammonium sulfate and calcium carbonate products
US11148956B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 22, 2020 |
| Grant date | Oct 19, 2021 |
| Priority date | — |
| Expiry date | Jan 22, 2040 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/80
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Disclosed herein are system and methods for producing a high purity ammonium sulfate product as well as either a lower or a high purity calcium carbonate product by reacting flue gas desulfurization (FGD) gypsum feedstock in batch or continuous mode using synthesized ammonium carbonate from ammonia and carbon dioxide gases. The high purity calcium carbonate is obtained by using a precipitation catalyst, filtering out the impurities, then precipitating a high purity calcium carbonate. Alternatively, the lower purity calcium carbonate may be dissolved in acid, impurities filtered out, then a high purity calcium carbonate is precipitated out using a soluble carbonate salt.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.