Treatment of alkaline bauxite residue
US10494280B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 21, 2013 |
| Grant date | Dec 3, 2019 |
| Priority date | — |
| Expiry date | Oct 21, 2033 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC02F2103/16
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A process is disclosed for treating a Bayer process waste comprising a slurry containing bauxite residue and dissolved aluminum. The process comprises supplying the waste to a settling area to cause the bauxite residue to settle out of the slurry, thereby producing a supernatant liquor. The process further comprises neutralizing the supernatant liquor with a solution containing magnesium and calcium to produce a neutralized slurry containing precipitated hydrotalcites and thickening the neutralized slurry to produce a clarified effluent and a compacted slurry containing the precipitated hydrotalcites, part of said compacted slurry being recirculated to the supernatant liquor to be neutralized and/or directly to the neutralizing step. The clarified effluent and the compacted slurry are disposed of separately. Also disclosed is a plant for treating a Bayer process waste.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.