Abstract: In a method for manufacturing fibril cellulose, cellulose based fibre raw material is processed mechanically in a refining gap for separating fibrils. The fibres to be refined are subjected to the action of a surface roughness Ra provided by grits elevated from a refining surface delimiting the refining gap, said surface roughness being lower than 3 ?m, advantageously lower than 2 ?m. The refining surface is formed by spraying grits and binder onto a substrate.

Abstract: Described herein is nanocellulose produced by introducing a mixture of cellulose based fiber raw material and water through a refining gap, having a width smaller than 0.1 mm. In the refining gap, the fiber raw material is subjected to processing forces varying in the direction of introducing said mixture, by means of refining zones provided in the gap one after each other in the feeding direction, whereby the refining surfaces differ in surface patterning and/or surface roughness. The mixture of fiber raw material and water is guided past the refining surfaces in the feeding direction to different locations in the refining zone by by-pass channels provided in the stator. The width of the refining gap is maintained by the combined effect of the feeding pressure of the mixture of fiber raw material and water fed into the refining gap and the axial force of the rotor.

Abstract: Disclosed is a method for adding an additive to a cement-like composition, preferably a concrete mixture. The method includes forming a liquid flow, preferably a water flow; feeding an additive to the system; dosing said additive to said liquid flow by feeding it transversely and/or counter-currently to the liquid flow in such a way that mixture is formed which includes said additive and nanocellulose; and adding the formed mixture as an additive to a cement-like composition. Furthermore, disclosed is a cement-like composition and to an apparatus for adding an additive to a cement-like composition.

Abstract: Described herein is nanocellulose produced by introducing a mixture of cellulose based fiber raw material and water through a refining gap, having a width smaller than 0.1 mm. In the refining gap, the fiber raw material is subjected to processing forces varying in the direction of introducing said mixture, by means of refining zones provided in the gap one after each other in the feeding direction, whereby the refining surfaces differ in surface patterning and/or surface roughness. The mixture of fiber raw material and water is guided past the refining surfaces in the feeding direction to different locations in the refining zone by by-pass channels provided in the stator. The width of the refining gap is maintained by the combined effect of the feeding pressure of the mixture of fiber raw material and water fed into the refining gap and the axial force of the rotor.

Abstract: A method and system for producing nanocellulose are provided. Cellulose is refined by a first refiner, the refined cellulose is separated by a first separator in such a manner that at least part of it belongs to an accepted fraction, water is removed from the accepted fraction by a precipitator and the accepted fraction is refined by a second refiner to produce nanocellulose.