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:
Mar. 18, 2003
Filed:
Jun. 08, 2000
Applicant:
Inventors:
Assignee:
Metso Chemical Pulping Oy, , FI;
Primary Examiner:
Int. Cl.
CPC ...
D21C 3/04 ; D21C 3/06 ; D21C 3/26 ; D21C 9/02 ;
U.S. Cl.
CPC ...
D21C 3/04 ; D21C 3/06 ; D21C 3/26 ; D21C 9/02 ;
Abstract
A method for preparing pulp from lignin-containing cellulosic material is disclosed, including a step for acid cleaning of the lignocellulosic material, followed by alkaline delignification. The acidic step removes undesired components such as metal ions and side groups of polysaccharides, which may have adverse effects on the process especially when extensive recycling of liquors is employed within the plant.