Abstract: The method is for separation of lignin from original black liquor (BLIN) that has a first precipitation stage (PR) for precipitation of lignin by a first acidification using acidifier AC1, preferably using CO2, at alkaline conditions, then separating a lignin cake with subsequent suspension of the lignin cake in a strong acid in order to leach our metals from the lignin followed by dewatering and obtaining a clean lignin product LP. The process further is improved by intensified hydrolysis of lignin cake such that most of the carbohydrates are broken down to dissolvable monomers that could be separated from the lignin in the filtrate from a filtering stage subsequent to the hydrolysis. The improved hydrolysis could reduce as much as 90% of the carbohydrate content using a moderately increased temperature and increased charge of acidifier while avoiding any larger lignin yield losses.

Abstract: A center plate for a rotor in a pulp refiner has a surface provided with at least one feeding wing for directing lignocellulose-containing material towards a periphery. The feeding wing is an elongated protrusion arranged such that its second end is arranged further away from a center of the center plate than a first end and also is displaced relative to the first end in a direction opposite to a direction of rotation of the rotor. The center plate is also provided with at least one counter-feeding wing for directing steam flowing along the surface towards the center of the center plate. The counter-feeding wing is an elongated protrusion arranged such that a second end of the counter-feeding wing is arranged further away from the center of the center plate than a first end and closer to the center of the center plate than the first end.

Abstract: A center plate for a rotor in a pulp refiner has a surface provided with at least one feeding wing for directing lignocellulose-containing material towards a periphery of the center plate. The at least one feeding wing is an elongated protrusion arranged such that its second end is arranged further away from a center of the center plate than a first end and is also displaced relative to the first end in a direction opposite to a direction of rotation of the rotor. The at least one feeding wing includes at least one opening allowing steam to flow through the opening in a direction having a component directed opposite to the direction of rotation.

Abstract: An arrangement for feeding and dewatering lignocellulosic material in a hydrolysis process between a first reactor unit, where the material is partly hydrolyzed, to a second reactor unit, wherein the first reactor unit operates at a first pressure and the second reactor unit operates at a second pressure being higher than the first pressure. The arrangement includes a first plug screw feeder arranged to receive the partly hydrolyzed material from the first reactor unit and being arranged to compress, dewater and transport the material, wherein the first screw feeder is arranged to operate at a pressure being higher than the first pressure. A dilution vessel is coupled to receive material from the first plug screw feeder and including a liquid inlet for receiving liquid to wash the material, wherein the dilution vessel is arranged to maintain or increase the pressure (PDM).

Abstract: The method and apparatus are for obtaining strong white liquor and lime mud with low residual alkali content from causticized liquor. The first filter (FWL) receives causticized liquor from causticizing vessels (CT1-CT2-CT3) and is designed as pressurized two stage disc filter with 2 separate vat parts. In the first vat part non-diluted white liquor is obtained as a filtrate from the causticized liquor. The first lime mud cake accumulated on the filter discs in the first vat part is scraped off and diluted before being fed to the second vat part. In the second vat part weak liquor is obtained as a filtrate from the re-slurried first lime mud cake. The second lime mud cake accumulated on the filter discs in the second vat part is washed before being scraped off and diluted before being fed to subsequent lime mud handling.

Abstract: In an outlet flow control arrangement (1) arrangeable to control a flow of material through an outlet (2) with a predetermined diameter arranged at an end of a pressurized processing container (3), the outlet flow control arrangement (1) comprises an adaptor unit (4) configured so that a cross-section of a flow into the adaptor unit (4) is reduced as compared to a cross-section of the outlet (2), to enable the adaptor unit (4) to control and center a flow of processed material out of the processing container (3) and through the outlet (2) into a discharge pipe (5).

Abstract: The invention is related to improved polysulfide production process wherein a specific second filtration process (Fx) is installed before the polysulfide reactor (Rc). According to the inventive method a cross flow filter (Fx) is used as the second filtration process reaching astonishing low levels of residual solids in the white liquor as well as extended availability of the second filtration process. The subsequent polysulfide reactor, either in form of an electrolytic cell or in form of a bed of active carbon, could then also be operated at increased availability. The invention increases the production volume of polysulfide and the retentate from the cross filtering process may be bled out continuously to a process position ahead of a first filtering or clarification stage, capturing most of the increased content of lime mud particles in the retentate and causing less disturbance of the process with a minimum of tanks and pumps.

Abstract: A center plate for a rotor in a pulp refiner is described in which the center plate is provided with a plurality of first wings for directing pulp flowing onto the center portion of the center plate towards the periphery of the center plate, each of the first wings comprising an arc-shaped protrusion extending between a corresponding first point and a corresponding second point on the surface of the center plate, the first point being displaced from the center portion of the center plate and the second point being disposed further from said center portion of the center plate then the first point, the first wings having an arc shape that yields a larger pulp feeding angle then that of a circular arc intersecting the center portion of the center plate and ending in the same corresponding second point, and the second point of each of the first wings lies on the periphery of the center plate.

Abstract: A cyclone separator (10) comprises a pressure chamber (20), an inlet (30) for an incoming flow of a mixture of gas and particles, a gas outlet (50) for outgoing gas arranged through a top wall (26) of the pressure chamber and a particle outlet (40) for outgoing particles arranged in a lower part (22) of the pressure chamber. The pressure chamber has a main rotation symmetric shape. The inlet is arranged through a side wall (28) of an upper part (24) of the pressure chamber for directing the incoming flow with a main velocity component in a tangential direction. The inlet comprises an inlet tube (36) protruding through the side wall of the upper part into the pressure chamber, whereby an inner end (38) of the inlet tube is provided at a position interior of the pressure chamber. A method for operating a cyclone separator is also disclosed.

Abstract: A discharge valve is disclosed which includes a valve housing which can be functionally connected to a process element having a pressurized interior space. The valve housing includes a flow channel having a longitudinal center axis (A) and is in working cooperation with a valve member. The flow channel is arranged to be in fluid communication with the pressurized interior space in the process element after the discharge valve has been connected to the process element. The valve member is displaceable between an open position and a closed position in a displacement direction (B) whereby the discharge valve can be opened and closed. The flow channel comprises a detachable inner lining having an envelope wall, and the detachable inner lining comprises an aperture extending through the envelope wall and through which the valve member is adapted to run when being displaced between the opened and closed positions.

Abstract: The invention relates to a refiner plate segment in a refiner plate for mechanically refining of lignocellulosic material in a refiner, said refiner plate segment comprising at least a first, generally radially extending bar, a second, generally radially extending bar, a groove arranged and defined between said first, generally radially extending bar and said second, generally radially extending bar, and a main dam, which has a height H and is arranged in the groove, wherein a pre-dam is arranged in front of the main dam, said pre-dam has a height h which is less than the height H of the main dam.

Abstract: The bin arrangement is for collecting and discharging smaller ligno-cellulosic material. The bin has a transition part from a circular section of the bin and downwardly to a rectangular section with a long and short side of the rectangular section. The transition part could be built with few wall segments, thus needing less welding. Two rotary pocket feeders, each with at least one shaft extending parallel to the long side, are arranged directly under the rectangular section, enabling a uniform feed from the bin. The use of two rotary pocket feeders with this design directly under the bin does not destroy the even feed of material through the bin part, which otherwise is experienced from using conventional feed screws that feed material in a transverse direction from the bin outlet. The bin does not need to have a complex bin design which converges to a small circular inlet to a conventional rotary pocket feeder.

Abstract: A feeding arrangement for feeding lignocellulosic biomass material such as annual plant material towards a hydrolysis process includes at least one transportation device for transporting the biomass material towards the treatment process; and at least one tearing roll arranged at a predetermined distance from the at least one transportation device and being provided with tearing protrusion. The at least one tearing roll is arranged with a predetermined distance to the at least one transportation device to tear off parts of the transported material to provide a substantially continuous flow of material.

Abstract: The invention relates to an improved profile bar screen for draining treatment liquor from a suspension of comminuted cellulose material and treatment liquor in an essentially cylindrical digester vessel. According to the invention is a profile bar screen designed with horizontal support arches 11 with integrated support shoulders 12 only at the outer ends of the support arch which support shoulders rest against the inside of the vessel wall 1. The invention combines the techniques from self-supporting screens with support members of weaker screen designs, avoiding need to make any additional welds in the classified pressure vessel wall of the digester. Installation of new screens in compartments previously equipped with blind plates in checkered screen rows may be done quickly and at less costs during shorter down time of digester.

Abstract: The method is for separation of lignin from original black liquor (BLIN) that has a first precipitation phase (PR1/PR2) for precipitation of lignin by a first acidification using acidifier, CO2, at alkaline conditions, then separating a lignin cake with subsequent suspension of the lignin cake in a strong acid in order to leach out metals from the lignin followed by dewatering and obtaining a clean lignin product LP. Lignin germ particles (LG) are added to the original black liquor in the first precipitation stage, preferably between two phases in said precipitation stage, in order to increase lignin particle growth on such lignin germ particles instead of spontaneous nucleation of lignin particles in said original black liquor. This results in improved filterability in subsequent dewatering and lignin cake formation and hence an increased lignin yield.

Abstract: The invention is related to a method for the preparation of kraft pulp with increased pulping yield from lignin-containing cellulosic material using polysulfide cooking liquor. In order to obtain a cost efficient system both in aspects of investment costs but also in aspects of heat economy of operating the process is most of the total charge of alkali charged as heated polysulfide liquor to an first atmospheric vessel, wherein the hot polysulfide liquor flashes off steam providing most if not all of the necessary steaming effect for the cellulose material. The polysulfide liquor is then allowed to impregnate the cellulose material at a temperature closer to cooking temperature but still so low that essentially no delignification occurs in impregnation vessel, as the H-factor in impregnation vessel is kept within 1-20.

Abstract: The invention relates to a welding head for magnetic pulse welding of hollow thin-walled profile to an inner member having a complementary outer form to said hollow thin-walled profile. The weld head comprises two movable weld head halves (10a,10b) forming said weld head wherein each half has at least one individual induction coil (12a,12b) connected to a power source independently from the other weld head half, with coils wound in a kidney-shape. The work piece is clamped between shapers (15a,15b) integrated with each half. With this weld head could for example work pieces such as tubular thin-walled profiles be welded, even if they are integrated in a closed tubular design, as the weld head could be closed quickly over the welding position and opened for release of the work piece without experiencing arching in clamping area.

Abstract: A plug screw feeder (1) comprises a plug screw (10) with a thread (12) and a plug screw housing (20) surrounding the plug screw. The plug screw housing comprises an inlet opening (24) in a side of the plug screw and in a vicinity of a first axial end (18) of the plug screw. The plug screw is arranged for feeding lignocellulosic biomass material (99) from the inlet opening to a second axial end (19) of the plug screw when being rotated. The thread, in at least a part of an inlet section (15) of the plug screw, presents a jagged peripheral rim (14A) with an inwards directed leading edge. The inlet section is defined as the section of the plug screw passing the inlet opening during rotation. A feeding arrangement and system for treatment of lignocellulosic biomass material comprising such a plug screw feeder is also disclosed.

Abstract: An arrangement for feeding and dewatering lignocellulosic material in a hydrolysis process between a first reactor unit, where the material is partly hydrolyzed, to a second reactor unit, wherein the first reactor unit operates at a first pressure and the second reactor unit operates at a second pressure being higher than the first pressure. The arrangement includes a first plug screw feeder arranged to receive the partly hydrolyzed material from the first reactor unit and being arranged to compress, dewater and transport the material, wherein the first screw feeder is arranged to operate at a pressure being higher than the first pressure. A dilution vessel is coupled to receive material from the first plug screw feeder and including a liquid inlet for receiving liquid to wash the material, wherein the dilution vessel is arranged to maintain or increase the pressure (PDM).

Abstract: A steam separation unit for separation of steam from lignocellulosic biomass material in a hydrolysis process includes a treatment vessel including a separation section and a biomass collection section. The separation section is arranged with at least one inlet for receiving at least partly hydrolyzed biomass material mixed with steam and at least one control outlet for discharging the steam from the vessel. A biomass collection section arranged to be filled at least partly with liquid during operation and coupled to the separation section to collect the biomass material after separation from steam, wherein the biomass collection section includes a mixing element for mixing the biomass material with liquid and at least one control valve for discharging biomass material mixed with liquid. A system for hydrolysis of lignocellulosic biomass material including such a separation unit is also presented.