Apparatus for decomposing sodium aluminate liquors without agitation to produce alumina
US4762684A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 13, 1987 |
| Grant date | Aug 9, 1988 |
| Priority date | — |
| Expiry date | Jan 13, 2007 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/61
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method and apparatus for decomposing a sodium aluminate liquor supersaturated with alumina, obtained from alkaline action on bauxite by the Bayer process, is initiated by introduction of alumina trihydrate seed, thereby forming a suspension. The suspension is fed in at the top of a non-agitated reactor described as a "decomposer", and removed from the bottom of the decomposer; the speed at which the suspension moves downwardly is regulated at 1.5 to 10 meters per hour. The apparatus comprises a cylindrical-conical reactor which is fitted with an arrangement for feeding in the suspension at the top, and with an arrangement for taking out the suspension at the bottom. In one embodiment of the apparatus the suspension is taken from the base of the decomposer through an internal tube, with air injected into the bottom of it, is raised to the level of the top of the decomposer and is then sent downstream.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.