Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Waste paper or textile waste
Patent
1994-07-27
1996-04-02
Hastings, Karen M.
Paper making and fiber liberation
Processes of chemical liberation, recovery or purification...
Waste paper or textile waste
162 5, 162 8, 162 29, 162190, D21C 502
Patent
active
055037097
ABSTRACT:
Waste lignocellulosic material, for example brown kraft grocery bag and corrugated paperboard, is treated in a multi-step process to produce a recycle brownstock pulp having a sufficiently low kappa number that it may be bleached according to conventional means such that its final optical and strength properties are comparable to that of virgin pulps bleached according to similar means; biological enzymes are used in conjunction with medium consistency pulping to separate fibers and loosen contaminants, such as wax and adhesives; low temperature soaking of waste lignocellulosic material in an alkaline peroxide liquid using long reaction times is used to minimize energy consumption, degrade contaminants, and to selectively remove lignin; loosened contaminants and poorly bonding lignocellulose debris are removed by screening and cleaning methods; high consistency peroxygen cooking is used to substantially delignify the pulp and to destroy contaminants in an energy efficient manner; liquid streams are treated and internally recycled to reuse chemicals and to eliminate environmental liquid discharge; organic solids are recovered and incinerated as fuel to provide heat energy to the process; spent sodium salts are recovered as sodium hydroxide and reused in the process as a delignification agent; the recycled pulp can be employed in the manufacture of brown paper and paperboard products, or can be bleached to provide a pulp for white paper or paperboard products.
REFERENCES:
patent: 1860432 (1932-05-01), Richter
patent: 3251730 (1966-05-01), Watanabe
patent: 3274049 (1966-09-01), Gaschke et al.
patent: 4737238 (1988-04-01), de Ruvo
patent: 4806203 (1989-02-01), Elton
patent: 4946556 (1990-08-01), Prough
patent: 4980023 (1990-12-01), Salkinoja-Salonen
patent: 5011572 (1991-04-01), Parthasarathy et al.
patent: 5091054 (1992-02-01), Meier et al.
patent: 5147503 (1992-09-01), Nguyen
patent: 5173153 (1992-12-01), Terrett et al.
patent: 5179021 (1993-01-01), du Manoir et al.
patent: 5302244 (1994-04-01), Nguyen
Darlington, "Comparative Properties of Market Deinked Pulps", TAPPI Pulping Conference, p. 741 (1992).
"A Preliminary Engineering Study and Cost Implications of Converting Deinking Mills to Closed Cycle Operations," NCASI Special Report No. 94-03 (Mar. 1994).
Kohler, "Is Japanese Technology Right for Recycled Container-board in North America?" , Recovery and Use of OCC, Chp. 3, p. 98 (1993).
Abrahamsson, "Oxygen/Sodium Carbonate Bleaching of Kraft Pulp Pre-treated with Nitrogen Dioxide with Oxygen," Svensk Papperstidniny (1983).
Markham et al., "Medium Consistency Oxygen Delignification of Kraft Pulp for Yield and Production Increase", TAPPI Pulping Conference, p. 165 (1981).
Markham et al., "Oxygen Bleaching of Secondary Fiber Grades", TAPPI Journal, p. 168 (Dec. 1988).
Healey, "Alkali Soaking Ups Quality, Yield of Occused in Boxboard Furnishes," Pulp and Paper, p. 136 (Sep. 1990).
Li et al., "The Effects of Alkaline Leaching on Pulp Bleachability and Physical Properties," TAPPI Journal, 76:12 p. 159 (Dec. 1993).
McEwen et al., "Improving the Repulpability of Wax Coated Corrugated Paperboard", TAPPI Journal, 76:7 p. 116 (Jul. 1993).
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