Production of paper pulp from sugar mill bagasse
OwnerHorst Kruger, Wilhelm Berndt +4inventors
InventorsHorst Kruger, Wilhelm Berndt, Ursula Schwartzkopff, Franz J. Reitter, Theodor Hopner, Hans-Joachim Muhlig
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Abstract
Paper pulp is produced by a process in which raw sugar mill bagasse is moist depithed, wet bulk stored in the presence of an inorganic and organic preservative, wet depithed by hydraulic shearing in the presence of an inorganic color remover, pulped, washed, cleaned and dewatered.
Claims15
A process for the production of paper pulp from sugar mill bagasse comprising:
- (a) moist depithing raw sugar mill bagasse to remove up to about 66% of the pith content and leave residual pith;
- (b) wet bulk storing said partially depithed bagasse;
- (c) forming a aqueous suspension of the stored, partially depithed bagasse;
- (d) wet depithing the formed aqueous suspension of the stored, partially depithed bagasse by hydraulic shearing thereof while simultaneously adding 0.5-10 parts per 100 parts of suspension of a carbonate, sulfite, hydroxide, phosphate, polyphosphate, chlorite or hypochlorite of an alkali metal, magnesium, calcium or aluminum;
- (e) pulping the wet depithed bagasse of step (d) by a neutral sulfite semi-chemical process or thermo-mechanical defibration;
- (f) mechanically pulping the product of step (e);
- and
- (g) washing, screening, cleaning and dewatering the pulp produced in step (f).
In a process for the production of paper pulp from sugar mill bagasse which comprises wet bulk storing partially depithed bagasse, the improvement which comprises treating the partially depithed bagasse in wet bulk storage with an amount of a carbonate, phosphate, polyphosphate, sulfite, chlorite or hypochlorite of an alkali metal, magnesium, calcium or aluminum effective to preserve the partially depithed bagasse, and further treating the partially depithed bagasse in wet bulk storage with a second preservative, selected from the group consisting of an amount of (a) a C.sub.1-5 aliphatic acid;
- (b) a C.sub.1-5 aliphatic acid substituted by amino or halogen;
- (c) a C.sub.1-6 hydroxy acid;
- (d) an alkali metal, Al or aluminum phosphate salt of (a), (b) or (c);
- and (e) an amide of (a), (b) or (c), to preserve the partially depithed bagasse.
Dependencies are inferred from the claim text.