Patent · US Expired

Method for treatment of spent liquor

US7465372B2 · kind B2 · utility

0Cited by
28References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 4, 2002
Grant dateDec 16, 2008
Priority date
Expiry dateJul 4, 2022

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF23G2209/101
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

Method for treatment of spent liquor at a pulp mill, in which method at least a part of the spent liquor flow arriving from the evaporation plant is taken to a pyrolysis reactor, wherein it is pyrolysed at a temperature of 300-800° C. in order to separate evaporable compounds from the coke remaining in a solid state. The pyrolysis products, which are gases or liquids, may be used as fuel or they may be processed further. The coke resulting from the pyrolysis is burnt in a soda recovery boiler or in a gasification reactor to regenerate cooking chemicals. The method is suitable for recovery of chemicals and energy both in sulphate and sulphite processes and also in cooking methods based on organic solvents.

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