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:
Aug. 16, 1988
Filed:
Jul. 30, 1985
Applicant:
Inventor:
Per Hakan Ostman, Jorvas, FI;
Assignee:
Ekono Oy, Espoo, FI;
Primary Examiner:
Int. Cl.
CPC ...
D21C / ; D21C / ;
U.S. Cl.
CPC ...
162 39 ; 162 60 ; 162 62 ;
Abstract
A method for the production of cellulose by the batch cooking process, wherein the digester is filled with chips and cooking liquor, and the batch is cooked at elevated temperature and pressure in order to obtain a delignified cellulose pulp in the digester. For the impregnation stage a cooking liquor is used which contains a substantially higher amount of active chemicals than is required for the cooking of the batch, and before the actual delignification stage the active-chemical batch for the cooking is adjusted and the excess amount of active chemicals is removed by replacing it by part of the hot spent cooking liquor recovered from a previous cooking.