Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – With regeneration – reclamation – reuse – recycling or...
Reexamination Certificate
2008-05-13
2008-05-13
Griffin, Steven P. (Department: 1791)
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
With regeneration, reclamation, reuse, recycling or...
C162S029000, C423S562000
Reexamination Certificate
active
10991527
ABSTRACT:
Oxidized white liquor is heat treated to increase the concentration of polysulphide measured at 285 or 286 nm (PSUV) or measured at 416 nm (PSVIS) and the PSUV/PSGRor PSVIS/PSGRratio, whereby the content of active polysulphide in the total polysulphide is increased which active polysulphide can be exploited to increase pulp yield in Kraft pulping.
REFERENCES:
patent: 4024229 (1977-05-01), Smith et al.
patent: 5082526 (1992-01-01), Dorris
patent: PCT/US97/05591 (1997-11-01), None
patent: WO 97 42372 (1997-11-01), None
Database Paperchem ‘Online’, The Institute of Paper Science and Technology, Atlanta, GA, US; Database Accession No. AB4701536, Ringley, M.B.: “Laboratory Polysulfide Cooking of Loblolly Pine”, retrieved from Dialog XP002219846, abstract and Southern Pulp Paper MFR. 39, No. 1: 24-26, 28, 30-31 (Jan. 1976).
Multi-Stage Polysulphide Pulping Processes, Part 1, Basic Ideas and Low-Temperature Impregnation Studies on Black Spruce Heartwood, Clayton et al, Pulp and Paper Research Institute of Canada, Pointe Claire, Quebec, Dec. 1967, T-619 to T-630.
Factors Affecting Yield Increase and Fiber Quality in Polysulfide Pulping of Loblolly Pine, Other Softwoods and Red Oak, Sanyer et al, Tappi, vol. 47, No. 10, Oct. 1964, pp. 640-652.
Some Aspects of the Chemistry of Polysulfide Pulping, Ants Teder, Swedish Forest Products Research Laboratory, Stockholm, Sweden, May 1969.
Spectrophotometric Determination of Polysulfide Excess Sulfur in Aqueous Solutions, Ants Teder, The Central Laboratory of the Swedish Cellulose Industry (CCL), Stockholm, Sweden, No. 6, 197-200, Mar. 31, 1967.
Dorris Gilles Marcel
Hu Thomas Qiuxiong
Leclerc Denys Francois
Page Natalie
Uloth Victor Charles
Felton Michael J.
FPInnovations
Griffin Steven P.
Ogilvy Renault LLP
LandOfFree
Kraft pulp yield by heat treatment of polysulphide liquors... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Kraft pulp yield by heat treatment of polysulphide liquors..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Kraft pulp yield by heat treatment of polysulphide liquors... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3907755