A refining member including a refining body with a refining surface including first and second refiner bars separated by first and second refiner grooves. The first and second refiner bars extend from respective first and second radially inward positions to respective first and second radially outward positions. The first and second refiner bars have a respective first and second height extending upward from a floor of a respective, adjacent first or second refiner groove. The second height is a minimum height of the second refiner bars and is spaced apart from the second radially inward position, with the second height being at least about 0.35 mm less than the first height. The first refiner bars are adapted to refine wood fibers and the second refiner bars are adapted to break up fiber bundles.

There is provided a method of producing a paper, comprising the steps of: a) providing a pulp having a Schopper-Riegler (SR) number measured according to ISO 5267-1:1999 of 25-50, which pulp comprises at least 70% by weight sulphate or sulphite pulp; b) diluting the pulp to a consistency of 0.1%-0.9%; and c) forming a web from the diluted pulp from step b) in a forming section at a machine speed of at least 1100 m/min, such as 1100-1800 m/min.

The present invention relates to a refined cellulose fiber composition useful as a strength enhancing agent for paper and paperboard, wherein the refined cellulose fiber composition has a Schopper-Riegler (SR) number in the range of 80-98 as determined by standard ISO 5267-1, and wherein the refined cellulose fiber composition has a content of fibers having a length >0.2 mm of at least 12 million fibers per gram based on dry weight. The invention further relates to a method for preparing the refined cellulose fiber composition and to pulp paper and paperboard comprising the refined cellulose fiber composition.

A method for manufacturing microfibrillated cellulose, a particulate grinding medium suitable for use in said method, a material which wears rough, and a method for making said particulate grinding medium.

A method for manufacturing microfibrillated cellulose, a particulate grinding medium suitable for use in said method, a material which wears rough, and a method for making said particulate grinding medium.

A fiber blend includes a first amount of wood pulp fibers refined in an amount of at least about 150 kWh per metric ton of gross refining energy, and a second amount of wood pulp fibers refined in an amount of at most about 10 kWh per metric ton of gross refining energy.

A method for preparing unbleached biomechanical pulp from straw. A straw is used as a raw material, which is treated with alkaline biological enzymes, heated with hot alkali steam, refined, and washed. The mechanical pulp prepared by the method of the present invention has significantly improved ring-crush strength, can be used to prepare corrugated paper or cardboard paper, and can significantly improve the compressive strength of the carton.

A disperser apparatus includes: a first disperser assembly configured to rotate around an axis; and a second disperser assembly facing the first disperser assembly. The first and second disperser assemblies each have a plurality of disperser-refiner plate segments annularly arranged. Each of the disperser-refiner plate segments includes a substrate having teeth extending from the substrate and arranged in rows disposed at radial intervals defining a dispersion section. Each tooth has a tooth height; and walls; and edges at junctions of adjacent walls. Each of the disperser-refiner plate segments further includes a refining section of refiner bars extending from the substrate, wherein adjacent refiner bars and the substrate define a groove between the adjacent refiner bars; and a plurality transition bars disposed between radially outermost teeth and the refining section.

A method for manufacturing microfibrillated cellulose, a particulate grinding medium suitable for use in said method, a material which wears rough, and a method for making said particulate grinding medium.

A method for manufacturing microfibrillated cellulose, a particulate grinding medium suitable for use in said method, a material which wears rough, and a method for making said particulate grinding medium.