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:
Jul. 05, 2016
Filed:
Feb. 21, 2008
Fredrik Ohman, Gavel, SE;
Hans Theliander, Göteborg, SE;
Per Tomani, Huddinge, SE;
Peter Axegard, Solna, SE;
Fredrik Ohman, Gavel, SE;
Hans Theliander, Göteborg, SE;
Per Tomani, Huddinge, SE;
Peter Axegard, Solna, SE;
Valmet Aktiebolag, Sundsvall, SE;
Abstract
The method is for controlling a sodium and sulphur balance of a pulp mill while separating lignin from black liquor. Lignin is precipitated by using an acid followed by filtration. The lignin filter cake thus obtained is re-suspended in acidic liquid and dewatered to form a second cake. The filtrate obtained after dewatering of the second cake is returned for washing and suspension of the first cake. Sodium sulphate-rich ESP (electrostatic precipitator) dust produced in the recovery boiler is used in the washing of the precipitated lignin cake.