Title:
METHOD FOR LIGNIN SEPARATION FROM BLACK LIQUOR COMPRISING MULTIPLE ACIDIFICATION STEPS
Document Type and Number:
WIPO Patent Application WO/2012/177198
Kind Code:
A8
Abstract:
The present invention relates to a method for separation of lignin from original black liquor (BLIN) comprising the following phases in sequence; a first precipitation phase (PR1) for precipitation of lignin by a first acidification of the original black liquor by adding a first acid or mixture of acids (G1a); followed by a second precipitation phase (PR2) for precipitation of lignin by a further acidification of the original black liquor by adding a second acid or mixture of acids (G1b). According to the invention is the first phase implemented to lower the pH while avoiding any larger amount of precipitation, i.e. less than 2-5%, while the second phase is implemented in order to obtain the larger part of the precipitation. In total is 40-70% of the total lignin content of the original black liquor precipitated while the residual black liquor after precipitation is still strongly alkaline.
Inventors:
BJOERKLUND PETER (SE)
WIMBY MARTIN (SE)
WALLMO HENRIK (SE)
WIMBY MARTIN (SE)
WALLMO HENRIK (SE)
Application Number:
PCT/SE2011/050830
Publication Date:
January 23, 2014
Filing Date:
June 22, 2011
Export Citation:
Assignee:
METSO POWER AB (SE)
BJOERKLUND PETER (SE)
WIMBY MARTIN (SE)
WALLMO HENRIK (SE)
BJOERKLUND PETER (SE)
WIMBY MARTIN (SE)
WALLMO HENRIK (SE)
International Classes:
D21C11/00; C07G1/00; C08H8/00
Attorney, Agent or Firm:
FURHEM, Hans (Box 1033, Karlstad, SE)
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