Title:
【発明の名称】パルプ化薬品回収系中の塩化物の低減
Document Type and Number:
Japanese Patent JP2630507
Kind Code:
B2
Abstract:
PCT No. PCT/SE93/00688 Sec. 371 Date Feb. 23, 1995 Sec. 102(e) Date Feb. 23, 1995 PCT Filed Aug. 18, 1993 PCT Pub. No. WO94/04747 PCT Pub. Date Mar. 3, 1994The present invention relates to an environmental-friendly process for reducing the content of chloride in a liquor inventory of a chemical pulp mill. According to the invention, in a recovery system for pulping chemicals containing sulphur and an alkali metal, precipitator dust formed in a recovery boiler is collected and withdrawn, dissolved in water and electrolyzed for production of chlorine or hydrochloric acid in the anolyte. Since the dust normally contains a large amount of sodium sulphate, sulphuric acid and sodium hydroxide can also be produced in the electrolysis. To reduce the content of impurities, before the electrolysis, the pH of the aqueous solution is adjusted to above about 10 to precipitate inorganic substances which are separated-off together with flocculated or undissolved substances.
Inventors:
RINDOBAAGU HANSU
SUNDOBURAADO BIRUGITSUTA
SUNDOBURAADO BIRUGITSUTA
Application Number:
JP50616893A
Publication Date:
July 16, 1997
Filing Date:
August 18, 1993
Export Citation:
Assignee:
EKA NOOBERU AB
International Classes:
D21C11/04; D21C11/00; D21C11/06; D21C11/12; (IPC1-7): D21C11/00
Attorney, Agent or Firm:
Tatsuo Ito (1 outside)