Crud handling circuit
US4190633A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1977 |
| Grant date | Feb 26, 1980 |
| Priority date | — |
| Expiry date | Apr 8, 1997 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01B25/461
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method for handling the problem of crud formation in the solvent extraction of wet-process phosphoric acid is described. Crud is the name ordinarily given to the thick interfacial layer of semi-floatable material which tends to form and accumulate, and which interferes with many of the extraction processes and, in particular, with the solvent extraction of wet-process phosphoric acid. The method described provides for the operation of the solvent extraction stages in a manner that allows the formation and temporary accumulation of crud in those stages whereupon the solvent and the crud are then removed from the extraction stages and treated in a series of operations which include a clarification step, an acid removal step, a water wash step and a caustic treatment step, which steps effectively separate the solvent from the crud, and remove the crud components from the system and regenerate otherwise unusable solvent. The invention is particularly applicable to the solvent extraction of wet-process phosphoric acid for the recovery of uranium by the reductive stripping technique.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.