Method for reducing alumina or magnesia by utilizing supersonic gas flow
US9617620B2 · kind B2 · utility
Inventors
Key dates
| Filing date | Mar 8, 2013 |
| Grant date | Apr 11, 2017 |
| Priority date | — |
| Expiry date | Jul 18, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22B21/04
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An alumina- or magnesia-reducing process in which a greenhouse gas or substance harmful to the human body is not emitted, which can achieve improved energy efficiency in comparison with the Hall-Heroult or Pidgeon methods. The process includes: introducing an alumina or magnesia powder with a carrier gas to the upstream side of a throat provided on a reducing unit; pressure-transferring the powder and carrier gas to the throat by an operative gas introduced to the upstream side of the throat; irradiating the throat with a laser beam to convert the alumina or magnesia into a plasma state and dissociate the alumina or magnesia thermally; jetting the thermally dissociated product through a nozzle provided on the downstream side of the throat at a supersonic speed to form a frozen flow; and isolating aluminum or magnesium. Hydrogen may be added to the operative gas to accelerate the reduction of alumina or magnesia.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.