The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 29, 1990
Filed:
Feb. 17, 1989
Applicant:
Inventors:
Erkki J Kiiskila, Karhula, FI;
Nils E Virkola, Helsinki, FI;
Assignee:
A. Ahlstrom Corporation, Karhula, FI;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D / ; D21C / ;
U.S. Cl.
CPC ...
159 473 ; 159D / ; 162 29 ; 162 3011 ;
Abstract
A method of decreasing the viscosity and improving the evaporability of sulfate black liquor from the cellulose cook includes raising the temperature of the black liquor above the cooking temperature so as to split the macro-molecular lignin fraction contained in the liquor. The temperature of the black liquor is maintained at the raised level for 1 to 60 minutes, preferably for 1 to 5 minutes.