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 invention relates to solid compositions comprising a fibrous material of natural origin obtained from plants, wherein the fibrous material comprises micro-scaled and/or nano-scaled fibril agglomerates, and an alditol; a method to obtain such compositions; compositions obtained by this method, products comprising such compositions; and the use of such compositions as formulation aid in such products.

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 invention relates to a system of producing MFC (micro fibrillated cellulose) having a process device (30) of a pulper, a refiner or a screen configured to process MFC suspension to consistency of 0.5-5%. The system has a continuous pressing means (15; 25, 26) configured to dry the MFC suspension to a consistency of 6-60%. A method of producing MFC has at least one process stage (30) which processes a MFC suspension to a consistency of 0.5-5% by a process device (30). In the process stage the MFC suspension is pulped in a pulping stage in a pulper and/or refined in a refining stage by a refiner and/or screened in a screening stage by a screen. The MFC suspension having the consistency of 0.5-5% is dried in a drying stage of continuous pressing (15, 25, 26) by continuous a pressing device (15, 25, 26) to a consistency of 6-60%.

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.

A method for preparing an aqueous suspension may include providing a fibrous substrate comprising cellulose having a Canadian Standard freeness equal to or less than 450 cm.sup.3, and microfibrillating the fibrous substrate in an aqueous environment by grinding in the presence of a grinding medium consisting essentially of mullite. The grinding may be carried out in the absence of grindable inorganic particulate material. The grinding medium may be present in an amount of at least about 10% by volume of the aqueous environment. The microfibrillated cellulose may have a fibre steepness of from about 20 to about 50.

The present invention relates to a process to produce highly microfibrillated cellulose (MFC) and nanofibrillated cellulose (NFC). The invention also refers to a microfibrillated/nanofibrillated cellulose produced according to such process. The microfib-rillated/nanofibrillated cellulose is obtained by subjecting a cellulose fiber in a slurry of cellulose pulp to multiple mechanical impacts. The cycle may be repeated several times. Non-cutting bars disposed in a ring formation is the preferred configuration. At least two rings concentrically arranged facing each other in high rotation transmit the kinetic energy to the fibers to provide the highly defibrillated microfibrillated/nanofibrillated cellulose.

A super strong and tough densified wood structure is formed by subjecting a cellulose-based natural wood material to a chemical treatment that partially removes lignin therefrom. The treated wood retains lumina of the natural wood, with cellulose nanofibers of cell walls being aligned. The treated wood is then pressed in a direction crossing the direction in which the lumina extend, such that the lumina collapse and any residual fluid within the wood is removed. As a result, the cell walls become entangled and hydrogen bonds are formed between adjacent cellulose nanofibers, thereby improving the strength and toughness of the wood among other mechanical properties. By further modifying, manipulating, or machining the densified wood, it can be adapted to various applications.