Abstract: A method for managing and controlling nitrogen emission from a cyclic liquor flow system in a pulp mill (1), the pulp mill (1) comprising a recovery system (20) for recovering heat and chemicals from a pulping process (30), the recovery system (20) comprising a recovery boiler (8) and a nitrogen oxide scrubber (15), the nitrogen oxide scrubber (15) being arranged to remove nitrogen oxide from flue gas (16) from the recovery boiler (8), the method comprising the steps of: —exposing flue gas (16) from the recovery oiler (8) to an oxidizing agent, thereby oxidising nitrogen oxide in the flue gas (16) to higher nitrogen oxides; —contacting the flue gas (16) with an alkaline aqueous scrubber liquid (17) in the nitrogen oxide scrubber (15), thereby absorbing the nitrogen oxides in the scrubber liquid (17) and producing a nitrogen containing scrubber liquid (17); —introducing all or a part of the nitrogen containing scrubber liquid (17) into the cyclic liquor flow system.

Abstract: A refiner for refining of lignocellulosic material includes a rotor disc and a stator disc. The rotor disc includes a first refining segment that includes a plurality of first protruding structures for grinding of the lignocellulosic material. Each of the first protruding structures is defined by a first height. The stator disc is arranged opposite the rotor disc and includes a second refining segment that includes a plurality of second protruding structures for grinding of the lignocellulosic material. Each of the second protruding structures being defined by a second height. The first height is at least three times larger than the second height.

Abstract: A method for processing pulp in an apparatus for washing and dewatering pulp, and a system for controlling this apparatus, the apparatus comprising two rotatable press rolls (102, 104) having a permeable outer surface (106, 108), and a vat (114, 116, 118), the press rolls (102, 104) defining a press nip (112) between them. The processing is determined by a set of variable operating parameters, which are adjusted and/or maintained during operation in response to deviations of measured values of control parameters in relation to their respective predetermined threshold values. The variable operating parameters include rotation speed of the press rolls. The control parameters include vat pressure and/or linear load.

Abstract: The present invention relates to a method for defibrating a lignocellulosic material in a steam explosion process, the method comprising: —supplying (1001) lignocellulosic material to a reactor (8), —treating (1002) the lignocellulosic material in the reactor (8) at a first pressure (P1), —discharging (1003) the lignocellulosic material from the reactor (8) to a vessel (13), wherein the vessel (13) is at a second pressure (P2) that is lower than the first pressure (P1) so that the lignocellulosic material is defibrated through steam explosion as it passes from the reactor (8), wherein lignocellulosic material is continuously supplied to and discharged from the reactor (8) in such a way that the first pressure (P1) is constant. The invention also relates to a defibration system for defibrating a lignocellulosic material in a steam explosion process.

Abstract: A system for treatment of a biomass material, said system comprising: a first vessel (3) in which said biomass material is treated under a first pressure; a second vessel (5) in which said biomass material is received and held at a second pressure which is lower than the first pressure; a transporting pipe (7) connecting an outlet (9) of the first vessel (3) with an inlet (11) of the second vessel (5) for transporting the biomass material from the first vessel to the second vessel; and a valve (15; 15?; 15) arranged in said transporting pipe (7), said valve being configured for controlling the flow of biomass material and fluid in the transporting pipe (7), wherein said transporting pipe (7) is asymmetrically connected to an outlet (33?; 33) of said valve (15; 15?; 15) such that a generated jet stream of biomass material delivered out from the outlet (33?; 33) of the valve (15; 15?; 15) is received closer to a transporting pipe longitudinal central axis (A1) than if the outlet (33?; 33) of the valve (15; 15?;

Abstract: The invention relates to a center ring arrangeable on a refining disc of a defibrator for refining of fibrous material, wherein said center ring comprises a circumferential outer surface, a circumferential inner surface and a centrally located through-hole adapted to receive fibrous material fed from a feeding device, wherein said outer surface is provided with a circumferentially running groove opening up on the outer surface and being adapted to collect steam produced during operation of said defibrator, and wherein the center ring further comprises a plurality of wings provided on said inner surface and a number of channels extending from said groove to the positions on said inner surface where said wings are provided.

Abstract: The disclosure relates to a method for producing of refiner disc segments. The method for producing of the invention allows for forming a multitude of refiner segments with only one forming process of a first die which may be lightweight and has reduced cost while at the same time a surface structure with high hardness which reduces wear of the die's surface. The method for producing a disc-type refiner segment for refining lignocellulosic material includes 3D printing a first model; forming a first die part using investment casting; 3D printing a second model; combining the first die part and the second model to create a first die model; using the first die model to generate for forming a sand model by compressing molding sand between the first die and the second die; and casting a refiner disc segment by casting a metal material using the sand model.

Abstract: The invention relates to a chip chute (4; 21; 31; 41) which comprises an elongated, open main body (22; 32; 42) having a rectangular transverse cross-section, and comprises further a transition portion (23; 33; 43), which connects to the elongated, open main body (22; 32; 42) and comprises a circular outlet (26; 36; 46). The invention relates further to a feeding system (1) for transporting comminuted lignocellulosic material from a vessel (2) to a pump (3) located below the vessel (2), wherein such a chip chute (4; 21; 31; 41) is arranged between the vessel (2) and the pum (3).

Abstract: A through-air apparatus for drying, curing, or bonding paper or non-woven products is provided. The apparatus includes a through-air roll configured for rotational movement about a first axis, where the through-air roll is configured to carry a web. The apparatus also includes a hood at least partially enclosing the through-air roll, and a cooling system positioned adjacent the through-air roll. The cooling system is configured to provide cool air to a web as the web leaves the through-air roll, and all of the cooling system is external to the through-air roll.

Abstract: Method for treating biomass, comprising compressing and dewatering (62) the biomass to a dry solid content of DS1% by weight; feeding (63) compressed biomass to a treatment vessel; adding (64) a treatment liquid to said treatment vessel; discharging (65) treated biomass; compressing and dewatering (66) discharged biomass to a dry solid content of DS2% by weight, and treating (68) the compressed and dewatered biomass in a hydrolysis reactor, wherein 1%<DS1?DS2<6%.

Abstract: According to the present invention, there is provided a cleaning system for biomass material handling systems and methods for such system. The cleaning system for a biomass material treatment stage in a continuous process system includes a hydrolysis or pre-hydrolysis reactor, a feeding arrangement is arranged to continuously feed biomass material to an inlet of the reactor, wherein reactor includes a reactor screw for moving the biomass material through the reactor and a discharge pipe including a discharge screw for continuously discharging treated biomass material. At least one high-pressure cleaning nozzle is arranged inside a housing of said reactor, wherein the at least one high-pressure cleaning nozzle is arranged to eject cleaning agent at predetermined intervals during operation of the reactor.

Abstract: A refiner plate that is adapted to be attached to a rotatable refiner disc on a refiner for mechanical treatment of lignocellulosic material. The refiner plate includes a refining surface that is adapted to be arranged oppositely a second refining surface of a second refiner disc on said refiner. The refining surface is provided with a plurality of refining bars, where at least one of the refining bars is provided with cavities that are at least partially embedded in the refining bars. At least one cavity provided on the at least one refining bar have one end arranged closer to the leading edge of a refining bar and one end arranged closer to the trailing edge of the refining bar and wherein the depth dimension of the cavity at the end is smaller than the depth dimension of the cavity at the end.

Abstract: A high performance through-air apparatus is provided. The though-air apparatus includes a through-air roll configured for rotational movement about a first axis, and a high flow circuitous air path inside of the apparatus that includes a path extending through a supply conduit, through the through-air roll, and also through an exhaust conduit. The through-air apparatus also includes a plurality of turning vanes positioned within the high flow circuitous path positioned to guide the flow of air through the apparatus. The through-air apparatus has a length, a width, a height, which together define a volume having a compact configuration. The high flow circuitous air path inside of the apparatus has a length, where the ratio of the volume of the through-air apparatus to the length of the high flow circuitous air path is less than 20 m2.

Abstract: A refiner segment that includes a center area. The refiner segment includes a number N, N?2, of bar zone that are arranged at different radial positions with regard to a radial direction R extending from the center area of the refiner disc towards the periphery of the refiner segment. Each of the bar zones are defined by a corresponding set of refining bars that are distributed angularly and encircles the center area. The refining bars belonging to different but neighboring bar zones are angularly offset and refining bars belonging to different but neighboring bar zones are arranged in such a way that a tangential direction of a particular refining bar belonging to a bar zone points in a direction towards the mid-point between two refining bars belonging to a neighboring bar zone.

Abstract: Alignment device (1) for adjusting a position of a curved shower bar nozzle flange (2) relative a permeable outer cylindrical surface (3) of a drum roll (4) of for instance a drum washer. The alignment device comprises a body element (8), an attachment device (9) and a contact element (11). The body element has a length adapted to a desired predetermined distance between the end (7) of the nozzle flange and the outer cylindrical surface (3). The attachment device (9) is arranged at a first end (10) of the body element (8) for releasably connecting the body element to the nozzle flange end (7) to extend tangentially therefrom. The contact element (11) is arranged at a second opposite end (12) of the body element, said contact element being adapted to abut against said permeable outer cylindrical surface (3). A method for aligning a nozzle flange using such an alignment device is also provided.

Abstract: A torque reaction arrangement (50) for twin press-roll pulp washers comprises a first torque reaction arm (10), a second torque reaction arm (20), a first link (19), and a second link (29). The links are provided between the ends of a respective torque reaction arm and a point close to the mounting to a respective stator of the other torque reaction arm. The torque reaction arms are rigidly mounted to a respective stator of a respective press roll motor. A twin press-roll pulp washer with such a torque reaction arrangement is also disclosed.

Abstract: The invention relates to a method for treating biomass (2). Biomass (2) is fed to a pressurized prehydrolysis reactor unit (8) by means of a feeding system (5, 7), wherein by means of the feeding system (5, 7) the biomass (2) is compressed. A filtrate is squeezed out of the biomass (2) by means of the feeding system (5, 7), in particular by a first plug screw (5) or a second plug screw (7) of the feeding system (5, 7). The biomass (2) is then thermally treated in the pressurized prehydrolysis reactor unit (8), discharged from the pressurized prehydrolysis reactor unit (8) afterwards, diluted with the filtrate before or after the discharge, and treated with an enzyme subsequently.

Abstract: The present invention relates to an improved method and device for treating biomass in which thermally treated biomass is discharged from a pressurized reactor and introduced into a blow tank and then a flash tank, wherein the absolute pressure in the blow tank is maintained above atmospheric pressure and the absolute pressure in the flash tank is maintained below atmospheric pressure. The slurry of biomass separated in the flash tank is then enzymatically treated. The heat from the thermally treated biomass is recovered from the latent heat of a vaporous aqueous stream withdrawn from the blow tank.

Abstract: The present invention relates to an improved method and device for treating biomass in which thermally treated biomass is discharged from a pressurized reactor and introduced into a blow tank, wherein the absolute pressure in the blow tank is maintained below atmospheric pressure. The slurry of biomass separated in the blow tank is then enzymatically treated.

Abstract: A refiner segment (101; 201) for use in a refiner disc (30; 30*) of a refiner (100) for refining of lignocellulosic material, said refiner segment (1) having an active surface comprising a plurality of bars (10) which are extending over the active surface (2) towards an outer periphery (18b) of the refiner segment, wherein at least three of the bars (10) comprises a last-box fluid connection (21) which is a fluid connection provided through the bar (10) for connecting a last box (23a) on one side of this bar with a last box (23a) on the other side of this bar (10) such that a pressure can be equalized between these two last boxes (23a) via the last-box fluid connection (21), wherein said last-box fluid connection (21) is provided in the bar (10) at a distance between 0.0-15.0 mm from the closest last dam (11a) which is extending from this bar (10) to another adjacent bar (10).