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:
Sep. 27, 1983
Filed:
May. 27, 1981
Applicant:
Inventor:
Hans O Samuelson, Gothenburg, SE;
Assignee:
Mo och Domsjo Aktiebolag, Ornskoldsvik, SE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C / ; D21C / ;
U.S. Cl.
CPC ...
162 40 ; 162 65 ; 162 81 ;
Abstract
A process is provided for the bleaching delignification of cellulose pulp with oxygen gas in the presence of alkali, wherein the pulp is first activated with nitrogen dioxide and then washed, preferably with water. The invention is characterized in that the acid solution obtained is used to pretreat the digested pulp subsequent to washing the pulp with waste liquor obtained from the oxygen gas bleaching delignification stage.