A method for controlling discharges of nitrogen compounds in the production of cellulose carbamate (CCA). Dissolving pulp (DP) or kraft pulp is produced at a pulp mill, and the DP or kraft pulp is activated. The activated pulp is reacted with urea to produce cellulose carbamate whereby ammonia is released. The cellulose carbamate production is integrated into the pulp mill having a flue gas system such that carbon dioxide from the flue gases is reacted with released ammonia to produce urea, which is used in the carbamate production.

The present invention relates to a process for manufacturing a fibre web, such as paper, board, tissue or the like. In the process bleached cellulose-containing fibres are suspended into process water in order to prepare a fibre stock, which comprises residual hydrogen peroxide. The process comprises at least one pulp storage tower through which the fibre stock is transferred before it is formed into a fibrous web and dried. Zinc ions are introduced to the fibre stock or one of its constituents to maintain the amount of residual hydrogen peroxide in the fibre stock at or above a predetermined threshold level after at least one pulp storage tower.

The present technology is directed to fluff pulps with improved odor control as well as methods of making such fluff pulps. A fluff pulp is provided that includes a bleached kraft fiber and a copper ion content from about 0.2 ppm to about 50 ppm by weight of the bleached kraft fiber. The bleached kraft fiber includes a length-weighted average fiber length of at least about 2 mm, a copper number of less than about 7, a carboxyl content of more than about 3.5 meq/100 grams; an ISO brightness of at least 80; and a viscosity from about 2 cps to about 9 cps.

According to an example aspect of the present invention, there is provided a process for the conversion of cellulosic waste material into a recycled cellulose product comprising the steps of cooking the waste material in a cooking liquor to remove lignin from the waste material and provide a delignified pulp, dissolving the delignified pulp in an ionic liquid to provide a spinning dope suitable for dry jet-wet spinning in an ionic liquid solution, and subjecting the spinning dope to a further processing step to provide a recycled cellulose product, said further step selected from the group of spinning cellulose fibers for use in textiles from the solution, extruding a film product for use in packaging, regenerating the dope as a hydrogel and regenerating the dope as an aerogel.

A fibrous cellulose-containing material capable of significantly improving resin strength and a method of preparation thereof, as well as a fibrous cellulose composite resin excellent in strength. The fibrous cellulose-containing material contains fibrous cellulose which is a carbamate-modified microfiber cellulose having hydroxyl groups, part or all of which are substituted with carbamate groups, and having an average fiber width of not smaller than 0.1 μm, and contains powder that is non-interactive with the fibrous cellulose. The fibrous cellulose composite resin contains fibrous cellulose which is the above-mentioned fibrous cellulose-containing material, and part or all of the resin is powdered resin. The method for preparing a fibrous cellulose-containing material includes adding at least either of powder that is non-interactive with fibrous cellulose and a dispersion thereof, to a dispersion of carbamate-modified microfiber cellulose to obtain a mixed liquid, and removing the dispersion medium from the mixed liquid.

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.

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 making a specialty fiber by activating pulp in an alkaline aqueous medium, then reacting it a water-soluble, multi-functional reagent able to bridge neighboring cellulose chain within a single fiber. The resultant specialty cellulose fibers have high intrinsic viscosity and may be used to make cellulose ethers, cellulose acetate, and viscose.

A method of producing nanocellulose includes defibrillating cellulosic raw material by oxidation with an oxidant such as NaClO or H202 and sonication in the presence of a swelling agent. The nanocellusose produced by the method can be used in a method of recycling cellulosic material such as paper, card, cardboard or wood to produce recycled paper.