A method for suppressing sedimentation of suspended substances ef the present invention is a method for suppressing sedimentation of suspended substances in water at the bottom of a tank disposed in a water system in papermaking equipment, comprising a step of blowing an oxygen-containing gas into the water, for stirring and aeration; a step of detecting a change with time in existence states of the suspended substances in the tank by the stirring and the aeration; and a control step of feeding at least one of an oxygen-containing gas and a slime control agent to the tank based on the detection result to suppress the sedimentation of the suspended substances in the tank.

Disclosed herein is a carboxylated cellulose nanofiber and a preparation method thereof. The method includes: mixing choline chloride, citric acid and water at 60-100° C. for 15-60 min to obtain a hydrated multi-carboxylic acid deep eutectic solvent (H-DES); mixing the H-DES and cellulose for hydrolysis-esterification reaction at 120-130° C. for 2-3 h to obtain a carboxylated cellulose; and mixing the carboxylated cellulose and water for nano-fibrillation to obtain the carboxylated cellulose nanofiber.

A method of increasing the throughput and/or decreasing the energy usage of a pulping process includes the steps of providing a plurality of lignocellulosic chips, providing a refining composition, applying the refining composition to the plurality of lignocellulosic chips, and mechanically refining the plurality of lignocellulosic chips to form pulp. The refining composition includes water and a lubricating additive including the reaction product of a sugar and an alcohol. The step of applying the refining composition to the lignocellulosic chips is conducted less than 5 minutes prior to, or concurrently with, the step of mechanically refining the wood chips to form pulp.

The present disclosure relates to tissue products comprising crosslinked fibers. The tissue products generally have good formation, such as a Formation Index greater than about 20, strength, such as geometric mean tensile strengths greater than about 700 g/3″ and high bulk, such as sheet bulks greater than about 10 cc/g. Unlike many prior art crosslinked fibers, the crosslinked softwood pulps of the present invention, which are preferably prepared using a glyoxal based crosslinking reagent, are readily dispersible in water and have relatively low degrees of kink and curl. As such, the fibers are well suited for forming wet-laid tissue products and more particularly wet-laid tissue products having improved physical properties, such as improved bulk.

The present invention relates to a method for manufacturing modified cellulose fibers for a moldable cellulose fiber based material, said method comprising: a) providing a chemical or semi-chemical wood pulp comprising cellulose fibers, and optionally subjecting the pulp to alkaline extraction to obtain an alkaline extracted pulp; and b) subjecting the pulp or the alkaline extracted pulp of step a) to a chemical treatment with an alkaline solution and/or an organic solvent to obtain a treated pulp or treated alkaline extracted pulp comprising modified cellulose fibers for a moldable cellulose fiber based material. The invention further relates to a moldable cellulose fiber based material comprising at least 70% by dry weight of modified cellulose fibers obtainable by the method.

The invention discloses a method to form a composition, which method includes fibrillating fibers to form MFC in the presence of an alkali-metal silicate whereby an MFC and silicate mixture is formed The presence of alkali-metal silicate during fibrillation of fibers to MFC, reduces the viscosity and increases the water release behavior, whereby the fibrillation can be accomplished at higher concentrations and a more uniform mixture of MFC-silicate is accomplished. The composition formed by the method of the invention may e.g. be used in paper or paperboard production, in cement production or as an additive in composites.

The present invention provides aqueous compositions for treating fluff pulp comprising (i) one or more acrylic acid polymers containing phosphinate groups and having a weight average molecular weight of from 1,000 to 6,000 and (ii) from 5 to 50 wt. %, based on the total solids weight of the aqueous compositions, of one or more polyethylene glycols, having a formula weight of from 150 to 7,000, or, preferably, from 200 to 600. The present invention also provides individualized, intrafiber crosslinked cellulosic fibers comprising the cellulosic fiber and, in cured form, the aqueous compositions, as well as methods of making the individualized, intrafiber crosslinked cellulosic fibers.

The present invention relates to the removal of hemicelluloses from paper-grade alkaline pulp thereby upgrading the pulp e.g. into dissolving-grade pulp using a combination of enzyme treatment, hot caustic extraction and optionally one or more bleaching steps.

An object is to optimize a bleaching process in a step of producing phosphorylated cellulose fibers. A pulp comprises cellulose fibers having 0.5 mmol/g or more of phosphoric acid groups or phosphoric acid group-derived substituents, when the pulp is processed into a sheet and four sheets are laminated on one another, the ISO whiteness of the laminate is 82% or more. Moreover, when the pulp is processed into a sheet and four sheets are then laminated on one another, the b* value of the obtained laminate according to the L*a*b* color system is 5.5 or less.

A process is provided for making a fluff pulp sheet, comprising contacting at least one cationic trivalent metal, salt thereof, or combination thereof with a composition comprising fluff pulp fibers and water at a first pH, to form a fluff pulp mixture; forming a web from the fluff pulp mixture; and applying at least one debonder surfactant to the web and raising the pH to a second pH, which is higher than the first pH, to make the fluff pulp sheet. A fluff pulp sheet is also provided, comprising a web comprising fluff pulp fibers; at least one cationic trivalent metal, salt thereof, or combination thereof; at least one debonder surfactant; and a fiberization energy of <145 kJ/kg. Products and uses of the fluff pulp sheet are also provided.