Low-consistency ozone delignification

Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – With agitation or forced circulation

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8111, 162 65, D21C 910

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active

042160545

ABSTRACT:
A slurry of cellulosic fiber and water having a consistency in the range of 0.017-4.9% of the total ungassed weight of fiber and water is bleached with ozone. This is done without the usual addition of organic additives. The water can include impurities created by the bleaching process. Rapid reaction times under 8 minutes and preferably under 5 minutes are achieved.
The reaction is enhanced in the consistency range of about 0.017-0.7%.
The slurry is mixed using a mixing energy of 0.002-1.0 horsepower per cubic foot of gassed slurry. The mixing energy will determine whether the gas-liquid or liquid-solid interface will limit the speed of the reactions. The passage of ozone from the gas to a liquid phase will be the limiting factor below about 0.2 horsepower per cubic foot of gassed slurry. The increasing presence of ozone in the liquid as the horsepower increases from about 0.2 to about 0.4 horsepower per cubic foot of gassed slurry indicates this is a zone in which both the gas-liquid and the liquid-solid interface are limiting factors. Above about 0.4 horsepower per cubic foot of gassed slurry the liquid-solid interface will be the limiting factor.
Superficial velocity of the ozone bearing gas is in a range of 200-3800 feet per hour. The ozone usually is 0.05-6% by weight of the total weight of the gas.

REFERENCES:
patent: 396325 (1889-01-01), Brin et al.
patent: 1957973 (1934-05-01), Campbell
patent: 2438100 (1948-03-01), Whitner
patent: 2466633 (1949-04-01), Brabender
patent: 3318657 (1967-05-01), Wade
patent: 3451888 (1969-06-01), Ancelle
patent: 3451888 (1969-06-01), Ancelle et al.
patent: 3663357 (1972-05-01), Liebergott
patent: 3832276 (1974-08-01), Roymoulik et al.
patent: 3966542 (1976-06-01), Oldshue
patent: 4036681 (1977-07-01), Holton
patent: 4080249 (1978-03-01), Kempf et al.
Cunningham et al., "The Action of Ozone on Cellulose", J. of Chem. Society, vol. 101 (1912), pp. 497-512, vol. 103, pp. 677-686 (1913).
Duree et al., "The Action of Ozone on Cellulose and Modified Cellulose", J. of the Textile Inst., (1938).
Pancirolli, Indi Carta (Milan), "Sulfate Pulp Bleaching Tests with Ozone", 3-1953, pp. 35-38.
Samuelson et al., "A Comparison Between the Degradation of Cotton and Wood Pulp", Svensk Papperstidning, 10/1953, pp. 779-784.
Schuerch, "Ozonization of Cellulose and Wood", Journal of Polymer Science: Part C, No. 2, 1963, pp. 79-95.
Katai et al., "Mechanism of Ozone Attack on .alpha.-Methyl Glucoside and Cellulosic Materials", J. of Polymer Science, 1966, pp. 2683-2703.
Moore et al., "The Resistance of Hemicelluloses in Wood Fiber to Degradation By Ozone", TAPPI, 1966, pp. 206-209.
Encyclopedia of Chemical Technology, vol. 14, pp. 412-414, 1967, "Ozone".
Soteland et al., "The Effect of Ozone on Some Properties of High Yield Pulps", Norsk Skogindustri, 2/1968, pp. 46-52.
"The Effect of Ozone on Some Properties of Groundwoods of Four Species, Part I; Soteland, Norsk Skogindustri, 3/1971, pp. 61-66.
Secrist et al., "Kraft Pulp Bleaching-II; Studies on the Ozonation of Chem Pulps", TAPPI 4/1971, pp. 581-584.
Liebergelt, "Sequential Treatment of Mechanical Pulps at High Consistency with H.sub.2 O.sub.2 & O.sub.3, " Pulp & Paper Mag of Canada, 9/1972, pp. 70-73.
Soteland, "Bleaching of Chemical Pulps with Oxygen & O.sub.3 ", Preprint, Vancouver Bleach. Conf., 1973, pp. 117-120.
Soteland, "Bleaching of Chem. Pulps with Oxygen and Ozone", Pulp & Paper Magazine of Can., 4-1974, pp. 91-96.
Buley, "Potential O.sub.2 Application in Pulp & Paper Ind.", TAPPI, 7-1973, pp. 101-104.
Soteland, "The Effect of O.sub.3 on Some Properties of T-M Pulps", Norsk Skogirdustri, 10/1973, pp. 274-277.
Soteland et al., "The Effect of Ozone on Mech. Pulps", Norsk Skogindustri, 6-1974, pp. 165-169.
Kamislima et al., "O.sub.3 Bleaching of Kraft Pulp: The Bleachability of the Pulps of Softwood & Hardwood", 19th Japanese Symposium on the Lignin Chemistry, 1974, pp. 73-76.
Grigorescu, "Oxygen Bleaching of Fibrous Pulps", Celluloza Si Hirtie, 23, (2), 1974, pp. 58-62.
"Potential Possibilities of Ozone", Paper, World Research & Development Number, 1975, pp. 56-67, 60-61.
Rothenburg et al., "Bleaching of O.sub.2 Pulps with O.sub.3 ", TAPPI, 8/1975, pp. 182-185.
Schuerch, "Ozonizaton of Cellulose and Wood", Journal of Polymer Science, No. 2, pp. 79-95 (1963).
Soteland, "The Effect of Ozone on Some Properties of Groundwoods of Four Species, Part, I, Norsk Skogindustri (1968).
Osawa et al., "The Action of Gaseous Reagents on Cellulosic Materials 11, Pulping of Wood with Ozone", TAPPI, vol. 46, No. 2 (2-1963).
Procter, "Ozone Gas Treatments of High Kappa Kraft-Pulps", Pulp & Paper Magazine of Canada, vol. 75, No. 6, (6-1974).

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