Use of seawater in flue gas desulfurization
US4804523A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 17, 1987 |
| Grant date | Feb 14, 1989 |
| Priority date | — |
| Expiry date | Jun 17, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2251/402
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Efficient removal of sulfur dioxide from a flue gas stream is achieved in a scrubber using a recirculating aqueous stream containing magnesium hydroxide and magnesium sulfite which together act as SO.sub.2 absorbents. Magnesium sulfite is derived from magnesium hydroxide, which is the product of a reaction between soluble magnesium from the seawater and calcium hydroxide added to the scrubbing system. Magnesium sulfite and bisulfite are oxidized to magnesium sulfate by the introduction of air. Magnesium sulfate is converted back to magnesium hydroxide by reaction with additional calcium hydroxide, with gypsum as a by-product. Gypsum is soluble in large amounts of seawater and may be returned to the ocean without adverse environmental impact.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.