Patent · US Expired

Process for washing gas formed by gasifying black liquor

US6113739A · kind A · utility

7Cited by
1References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 11, 1996
Grant dateSep 5, 2000
Priority date
Expiry dateDec 11, 2016

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P70/10
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

Process for recovering chemicals and energy from black liquor, where the black liquor is gasified with CO, CO.sub.2, CH.sub.4, H.sub.2, and H.sub.2 S, in gaseous form, and Na.sub.2 CO.sub.3, NaOH and Na.sub.2 S, in the form of drops of smelt, being principally formed. The mixture of gas and smelt is cooled, in a first stage, by direct contact with a cooling liquid, whereupon a part of the cooling liquid is volatilized, and the smelt drops are separated off and dissolved in the remaining part of the cooling liquid with the formation of a liquid bath of green liquor. In a second stage, the gas is washed and saturated with moisture by direct contact with a washing liquid bath. After the gas has been washed in the second stage, energy in the form of thermal energy and condensation heat is recovered from the gas in an indirect condenser. The contact between the gas and the liquid bath, consisting of green liquor, in the first stage is substantially less than the contact between the gas and the washing liquid bath, in the second stage. This is achieved, by the gas in the first stage not being permitted to bubble through the liquid bath, consisting of green liquor, in contrast to the seco…

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