Patent · US Expired

Make-up liquor and black liquor evaporating processing during pulp production

US4897157A · kind A · utility

9Cited by
2References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 15, 1988
Grant dateJan 30, 1990
Priority date
Expiry dateMar 15, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P70/10
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

The number 2 flash tank of a black liquor energy recovery system associated with a continuous pulp digester is eliminated, and other advantages are obtained. After flashing in the number 1 flash tank, concentrated black liquor passes to a multiple effect evaporator system as the heating fluid supplied to the last effect. The heated black liquor passes in heat exchange relationship with excess make-up liquor from the high pressure feeder circulation system and/or with portions of the extracted black liquor that have had more of their heat content removed, the heated black liquor effecting evaporation of the excess make-up liquor and/or portions of the black liquor. Steam from the steam relief of the steaming vessel may be used as a secondary heating fluid source for the first effect.

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