Patent · US Expired

Process of producing kraft pulping liquor by the oxidation of white liquor in the presence of lime mud

US5082526A · kind A · utility

32Cited by
4References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 5, 1990
Grant dateJan 21, 1992
Priority date
Expiry dateApr 5, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P40/40
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

Sodium sulfide or hydrosulfide is oxidized to produce sodium polysulfide and sodium hydroxide. Under appropriate conditions, the oxidation may be pursued further to convert all the sodium sulfide into sodium thiosulfate. The oxidation is carried out at or above atmospheric pressure in a mixed reactor or in a pipeline reactor, by sparging oxygen or air, in a mixture of white liquor and lime mud particles produced in the recausticizing plant of a kraft mill.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.