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. 14, 1989
Filed:
Nov. 18, 1987
Applicant:
Inventors:
Johan Gullichsen, Sjunde.ang., FI;
Pertti Hynninen, Helsinki, FI;
Assignee:
A. Ahlstrom Corporation, Karhula, FI;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C02F / ; D21C / ;
U.S. Cl.
CPC ...
162 29 ; 162 38 ; 162 39 ; 210713 ; 210724 ; 210726 ; 210928 ;
Abstract
A method of removing lignin from bleach plant effluents by using cellulose fibres. The method comprises an acidous phase during which sludge containing cellulose fibres is added to the acidous effluent, and an alkaline phase during which alkaline waste water is added to the effluent-sludge solution. A portion of the produced fraction containing fibres is recirculated to the acidous phase for reuse of the fibres.