Inhibiting the formation of TCA in a Bayer causticisation process
US7767190B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 28, 2002 |
| Grant date | Aug 3, 2010 |
| Priority date | — |
| Expiry date | Oct 14, 2023 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01F7/473
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An improved process for the causticisation of Bayer liquors in an alumina refinery, the process including the steps of reacting lime with aluminate ions in a Bayer liquor within a primary reactor under controlled conditions of low to moderate temperature (between 70-80° C.) and agitation, to form substantially only a hydrocalumite species and hydroxyl ions; and a secondary reactor wherein the hydrocalumite species formed is subjected to heating in contact with a Bayer liquor under controlled conditions so as to cause the hydrocalumite species to react with the liquor to form calcium carbonate, aluminate ions and hydroxyl ions, whereby a causticised Bayer liquor is obtained and wherein the efficiency of lime utilization is substantially increased and/or alumina losses are minimized.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.