Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Including recovery of organic by-product
Patent
1992-05-22
1994-07-05
Jones, W. Gary
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
Including recovery of organic by-product
162 16, 162 19, 162 29, 162 3011, 423DIG3, D21C 1100
Patent
active
053264339
ABSTRACT:
Paper pulp (e.g. kraft pulp) is produced utilizing at least two different supplies of cooking liquor, one having low sulfide content, and the other high sulfide content. The high sulfide content supply is typically used to impregnate the pulp or otherwise treat it first, while the second supply is used in other cooking stages (e.g. a digester), whether co-current or countercurrent. The different sulfur content liquors are obtained by heat treating (under pressure) black liquor to drive off sulfur compounds, and absorbing them into white liquor to produce a high sulfide stream. The low sulfide stream is made by conventional treatment of the black liquor after heat treating and evaporation. Utilizing multiple sulfide content supplies results in an optimum viscosity/kappa ratio and/or pulp strength properties for the pulp produced.
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Henricson Kaj
Jiang Jian E.
Ryham Rolf
Smith James W.
Ahlstrom Recovery Inc.
Jones W. Gary
Nguyen Dean T.
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