Method for producing high opacifying kaolin pigment
US5713998A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1995 |
| Grant date | Feb 3, 1998 |
| Priority date | — |
| Expiry date | Feb 14, 2015 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/90
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
An improvement is disclosed applicable to the method for producing a calcined kaolin by the steps of wet beneficiating a crude kaolin to form a slurry of the beneficiated kaolin; dewatering the slurry to form a substantially dry calciner feed; and calcining the feed at a temperature of at least 1450.degree. F. by passing a stream of hot gases through a calciner in which the kaolin feed is resident, whereby an exhaust stream of hot gases is generated which entrains quantities of partially calcined and hydrous kaolin pigment fines. The improvement, enabling useful application of the kaolin pigment fines, comprises recovering the kaolin pigment fines from the exhaust stream for use in papermaking. The fines can be recovered at a wet scrubber, and after being partially dewatered, shipped directly as a product slurry to the paper maker.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.