Process for fluidifying aqueous suspensions of red muds in the production of alumina by the bayer process
US5653946A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 1994 |
| Grant date | Aug 5, 1997 |
| Priority date | — |
| Expiry date | Jul 14, 2014 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01F7/0646
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Improved process for fluidifying flocculated aqueous suspensions of red muds in the production of alumina from bauxite by the Bayer process, which consists: PA0 in dissolving bauxite using sodium hydroxide; PA0 then, in decanting and in washing the red muds formed in order to separate them from the alumina in successive vats, while recycling the washing waters upstream; PA0 and finally, in eliminating the red muds thus treated; and in which a flocculant (F) consisting of a polyacrylamide of molecular weight greater than ten million is introduced into the suspension of one of the successive vats; wherein a dispersing agent (D) formed by an anionic acrylic acid polymer of molecular weight lower than fifty thousand is added simultaneously with said flocculant (F) to the suspension in the same vat.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.