US 12,146,262 B2 · Non-wood pulp having high brightness and low debris

Abstract

Disclosed are non-wood pulps having a fiber length greater than about 1.70 mm and a brightness of about 80% or greater. The relatively high degree of brightness is achieved without a loss of fiber length or pulp yield. The high degree of brightness and relatively long fiber length make the pulps well suited for the manufacture of wet-laid fibrous products, particularly wet-laid tissue products. The pulps may be prepared from plants of the family Asparagaceae by mechanical pulping and more preferably by a chemi-mechanical pulping using a sodium hydroxide alkaline peroxide solution where the primary pulp is cleaned to reduce debris prior to bleaching. Preferably the cleaned primary pulp has less than about 5 wt % debris prior to bleaching.

Claims26

Dependent claims

A method of manufacturing a non-wood pulp comprising the steps of:

a. providing a non-wood biomass derived from a plant of the family Asparagaceae;
b. cutting the biomass to a nominal size ranging from about 5.0 to about 20 mm prior to the step of compressing and macerating the biomass;
c. compressing and macerating the cut biomass with a compression screw and an aqueous solvent having a pH of about 7.0 or greater to extract water soluble solids and remove a portion of the epidermis from the cut biomass thereby yielding a bagasse;
d. impregnating the bagasse with a caustic solution and maintaining the impregnation for a first reaction time to produce an impregnated bagasse;
e. refining the impregnated bagasse under first refining conditions to produce a primary pulp;
and
f. bleaching the primary pulp to produce a secondary pulp.

4 more elements

A method of manufacturing a non-wood pulp comprising the steps of:

a. providing a non-wood biomass derived from a plant of the family Asparagaceae;
b. cutting the biomass to a nominal size ranging from about 5.0 to about 20 mm prior to the step of compressing and macerating the biomass;
c. compressing and macerating the cut biomass with a compression screw and an aqueous solvent having a pH of about 7.0 or greater to extract water soluble solids and remove a portion of the epidermis from the cut biomass thereby yielding a bagasse;
d. impregnating the bagasse with a first sodium hydroxide alkaline peroxide solution and maintaining the impregnation for a first reaction time to produce impregnated bagasse;
e. feeding the impregnated bagasse to refiner comprising a refining disc encased in a housing having an inlet and an outlet;
f. refining the impregnated bagasse under first refining conditions to produce a primary pulp;
g. discharging the primary pulp out of the refining housing through the outlet and adding a second sodium hydroxide alkaline peroxide solution to the discharged primary pulp;
h. cleaning the primary pulp to yield a cleaned primary pulp having less than about 5% debris,
i. delivering the cleaned primary pulp to a bleaching vessel;
and
j. adding a third sodium hydroxide alkaline peroxide solution to the cleaned primary pulp in the bleaching vessel to yield a bleached primary pulp.

8 more elements

Dependencies are inferred from the claim text.

Non-wood pulp having high brightness and low debris

Life of this patent

Non-wood pulp having high brightness and low debris

Life of this patent

Abstract

Claims26