Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – With regeneration – reclamation – reuse – recycling or...
Patent
1992-02-13
1994-11-01
Jones, W. Gary
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
With regeneration, reclamation, reuse, recycling or...
162 301, 162 29, 159 473, 159DIG8, D21C 1104
Patent
active
053605136
ABSTRACT:
Black liquor from a cellulose pulp processing plant is treated, including by using a direct contact (cascade) evaporator, without need for oxidizing the black liquor, without substantial sulphur emissions at the cascade evaporator, and by maximizing the solids content of the black liquor so that the loss of heating value of the black liquor is minimized. The black liquor is heated under temperature and time conditions sufficient to drive off most of the organic sulphur compounds as off gases, which gases are converted primarily to methane and hydrogen sulfide, with the methane separated by selective absorption in white liquor. The black liquor is then stripped of most remaining sulfur by bringing it into stripping contact with flue gases from the recovery boiler, the flue gases taken from downstream of the direct contact evaporator. After stripping, the solids content of the black liquor is increased (as by passing it to another evaporator), then it is led into association with the cascade evaporator, and then passed into the recovery boiler where it is combusted. The sulphur constituents of the off gases from the stripping operation are also passed into contact with white liquor.
REFERENCES:
patent: 2711430 (1955-06-01), Hagglund et al.
patent: 3425477 (1969-02-01), Farin
patent: 3560329 (1971-02-01), Nelson et al.
patent: 3607619 (1971-09-01), Hess et al.
patent: 3718446 (1973-02-01), Brink et al.
patent: 3762989 (1973-10-01), Timpe
patent: 4373109 (1983-02-01), Olah
patent: 4431617 (1984-02-01), Farin
patent: 4929307 (1990-05-01), Kiiskila et al.
patent: 4953607 (1990-09-01), Erkki et al.
Babcox & Wilcox "Steamn/Its Generation & Use" FIG. 3 on p. 20-9.
Brian Blackwell; "Chemical Reactions in Kraft Recovery Boilers"; pp. 157 and 158.
A. Ahlstrom Corporation
Jones W. Gary
Nguyen Dean T.
LandOfFree
Sulphur removal from gases associated with boilers having cascad does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Sulphur removal from gases associated with boilers having cascad, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Sulphur removal from gases associated with boilers having cascad will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1800425