Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – With regeneration – reclamation – reuse – recycling or...
Patent
1994-01-03
1995-04-11
Jones, W. Gary
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
With regeneration, reclamation, reuse, recycling or...
162 301, 162 3011, 423207, 423DIG3, D21C 1112
Patent
active
054054966
ABSTRACT:
The invention relates to a process for preparation, under reducing conditions, of cooking liquors having high sulphidity for sulphate pulp cooking, wherein the black liquor obtained in the cooking process is fed, after evaporation, completely or partly to a reactor operating at increased temperature which is obtained by energy supply from an external heat source and/or release of energy from the black liquor, a melt essentially consisting of sodium sulphide being formed and withdrawn to be further processed to cooking liquor. The process of the invention is characterized in that in addition there are fed to the reactor the whole or part of sulphur-containing and/or sulphur- and sodium-containing materials present in the pulp mill, including sulphur-containing and/or sodium- and sulphur-containing make-up chemicals used for the total chemicals balance of the pulp mill, in such a way that the mole ratio of sodium to sulphur in the total mixture fed to the reactor is within the range of 1.5 to 4. According to a preferred embodiment of the invention there is used an aqueous solution of the sodium sulphide melt obtained in so-called modified sulphate cooking.
REFERENCES:
patent: 2106952 (1938-02-01), Konig
patent: 3822180 (1974-07-01), Mita et al.
patent: 3867251 (1975-02-01), Holme
patent: 4098639 (1978-07-01), Noreus et al.
patent: 4451333 (1984-05-01), Bourson et al.
patent: 4710269 (1987-12-01), Santen et al.
patent: 4786365 (1988-11-01), Teder et al.
patent: 4808264 (1989-02-01), Kignell
patent: 5061343 (1991-10-01), Azarniouch et al.
Norden, Solveig "Modified Kraft Processes For Softwood Bleached-grade Pulp", TAPPI, Jul. 1979, vol. 2, 7, pp. 49-51.
Hedblom Mats-Olov
Lindberg Hans
Chemrec AB
Jones W. Gary
Nguyen Dean T.
LandOfFree
Process for the preparation of cooking liquors having high sulph does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for the preparation of cooking liquors having high sulph, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for the preparation of cooking liquors having high sulph will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1536295