Pretreatment by alkaline wetting and holding at temperature of natural materials having an argillaceous gangue containing combustible elements
US4702820A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 8, 1986 |
| Grant date | Oct 27, 1987 |
| Priority date | — |
| Expiry date | Aug 8, 2006 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G1/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Process for pretreatment at atmospheric pressure or a pressure close to atmospheric pressure by alkaline wetting and holding at temperature of natural materials whose gangue comprises argillaceous compounds capable of forming a stable plastic suspension in the presence of water and containing at least one combustible element which can be put into useful form wherein, in order to permit subsequent easy operations for separation of the liquid aqueous and solid phases of the gangue: PA0 (a) the natural material which was possibly been subjected to a preliminary drying operation is brought into intimate contact with at least 4 kg expressed in terms of OH.sup.- of at least one alkaline agent per ton of clay contained in said material, the total volume of liquid present in the natural material after the contacting operation being such that the ratio L/S of said volume expressed in terms of cubic meters to the weight of solid expressed in tons of dry ore is at most equal to 0.6; and PA0 (b) the natural material when wetted in that way is subjected to a pretreatment temperature that is suited to the nature of the combustible element and which is at most equal to 150.degree. C., for a perio…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.