Abstract: For the purpose of faciliating the impregnation of wood chips, the chips are compressed between two compression devices (9) which act on the mutually opposing flat sides of the chips (2). As the chips are compressed, the chips (2) are undulated or curved in at least one direction to produce a wave shape such that when the chips are seen in section at right angles to the waves, the top and the bottom sides (15, 16) of the wave crests will both be located on one side of a central plane (19) which passes through respective chips between the bottom sides (16) of the wave crests and the top sides (17) of the wave troughs, whereas the top and bottom sides (17, 18) of the wave troughs will both be located on the other side of the central plane (19).

Abstract: Methods for producing mechanical pulp are disclosed including impregnating softwood chips with water and a complexing agent, refining the impregnated chips in a first refining step including a double-disk refiner, fractionating the refined softwood pulp to produce a reject portion comprising beteen about 15 and 35% of the refined pulp and including an increased concentration of the long and stiff fibers therein, refining the reject portion in second and third refining steps in which the second refining step employs a greater concentration of pulp than does the third refining step, and fractionating the refined pulp.

Abstract: A method for discharging cooked lignocellulose materials from a digester is disclosed. After batch cooking the lignocellulose material in the digester is cooled to a temperature of about 100.degree. C., preferably from 100.degree. to 120.degree. C., a gas is supplied to the upper portion of the digester to provide a gas pressure such that the combination of that gas pressure and the static pressure in the digester created by the height of cooked lignocellulose material therein exceeds by no greater than about 200 kPa the sum of the pressure required to overcome the level difference between the exit port at the bottom of the digester and an entrance port in the upper portion of a receiving vessel and the flow resistance required to transfer the cooked lignocellulose material therethrough.

Abstract: Apparatus is disclosed for the manufacture of fiber pulp from lignocellulose-containing materials including radially extending grinding segments for use with a pair of opposed counter-rotating grinding discs in which the grinding segments include an inner radial zone with alternating raised bars and grooves projecting radially thereon parallel to the radius of the grinding segment, and an outer radial zone including a first group of alternating raised bars and grooves projecting outwardly thereon in a first direction and a second plurality of alternating raised bars and grooves projecting outwardly thereon in a second direction, both sets of these raised bars and grooves extending outwardly at angles of between about 5.degree. and 30.degree. with the first and second directions being opposite to each other with respect to the grinding segment itself. Methods for manufacturing fiber pulp from lignocellulose-containing material employing such grinding segments are also disclosed.

Abstract: Apparatus for treating material mixtures such as fiber mixtures is disclosed, including conically shaped corresponding inner and outer members defining a gap between their treating surfaces and being relatively rotatable with respect to each other, with at least one of the inner and outer treating surfaces including longitudinally extending grooves, and cleaning wings for cleaning the grooves protecting into the grooves and being movable along the grooves in order to do so.

Abstract: Apparatus for refining lignocellulose containing material is disclosed, including a refiner housing including a pair of refiner discs relatively rotatable about a pair of rotatable shafts. Each refiner disc includes a refiner element mounted thereon in a face-to-face relationship defining a refiner gap therebetween. The apparatus includes feed passages passing through the first refiner discs at a location proximate to the rotatable shaft for feeding the lignocellulose-containing material to the refiner gap element and the first refiner disc includes feeding wings corresponding to the feed passages and located partially in front of each such feed passage to accelerate the lignocellulose-containing material into the refiner gap, while the second refiner disc includes a substantially smooth surface portion at a location juxtaposed with the location of the feed passages in the first refiner disc.

Abstract: Methods for manufacturing fiber board sheets from defibered lignocellulose-containing material are disclosed, including drying the defibered lignocellulose-containing material with heated gas in a tube dryer, transferring the dried lignocellulose-containing material directly to a forming station, and forming the dried lignocellulose-containing material into a fiber web at the forming station whereby the temperature of the dried lignocellulose-containing material is substantially maintained from the drying step to the forming station. Apparatus for manufacturing fiber board sheets utilizing this method are also disclosed.

Abstract: Methods for determining the contact position between a pair of relatively rotating refining surfaces are disclosed including detecting the heat radiating from the initial contact between the pair of refining surfaces during relative rotation therebetween in order to generate an output signal and utilizing the output signal to determine the contact position. Apparatus for determining the contact position is also disclosed.