Causticizing process
US4762590A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 3, 1986 |
| Grant date | Aug 9, 1988 |
| Priority date | — |
| Expiry date | Jun 3, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S423/03
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The invention concerns a causticizing procedure by which from soda liquor derived from a sulphate cellulose digesting process and from unslaked lime is produced white liquor for reuse in the digesting process, over lime slaking and a subsequent causticizing reaction proper. It is essential in the invention that the lime slaking is carried out using white liquor, whereafter the causticizing reaction proper is allowed to take place between the slaked lime and soda liquor combined therewith. The requisite white liquor is obtained by recirculating part of the white liquor produced by the causticizing process, to the slaking step, where it either completely or partially replaces the soda liquor employed in prior art. By using white liquor, one avoids the foaming, interfering with the process, which is encountered in the slaking step.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.