Abstract: The present invention relates to an outlet system for transporting comminuted lignocellulosic material from a vessel, said bottom portion (1) having an upper circumference (15) that is essentially circular and a lower circumference (16) comprising at least two essentially straight portions (16a, 16c) opposite each other. The invention also relates to a vessel having such an outlet system.

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: A photocurable pressure-sensitive adhesive composition, a photocurable pressure-sensitive adhesive layer, and a photocurable pressure-sensitive adhesive sheet including a support and such a photocurable pressure-sensitive adhesive layer formed on at least one side of the support are provided. The photocurable pressure-sensitive adhesive composition can form an adhesive layer that has sufficient initial adhesive strength through the process of drying and cross-linking without having any adhesive protruding at normal temperatures and pressures, hardens easily with light irradiation, and has a high peeling resistance. The photocurable adhesive composition contains a graft polymer that graft-polymerizes a monomer containing a cyclic ether group to a (meth)acrylic polymer and a cationic photopolymerization initiator. The photocurable adhesive layer and the photocurable adhesive sheet are prepared by using said photocurable adhesive composition.

Abstract: The invention relates to a device for the hydrolysis of preferably solid organic substrates, in particular of energy crops and plant residues, with a collection vessel (1) for receiving the organic substrates, with a conveying means (4) for transporting the organic substrates into a charging device (7) for the batch-wise charging of a hydrolyzer (10) with the organic substrates, the hydrolyzer (10) being provided on the output with a pressure-release device (12) having a valve-controlled pressure diaphragm (13) and a steam trap (14) arranged upstream of an expander tank (15). According to the invention, the conveying means (4) includes a conveyor worm (4?) with a sleeve shaft (25), which is charged with hot steam from the steam trap (14), which is preferably designed as a cyclone, the sleeve shaft (25), in the conveying zone for the organic substrate, having, in a heating zone (18), steam-outlet openings (26) for directly charging the organic substrate with hot steam.

Abstract: A digester apparatus is provided for delignifying wood chips to form wood pulp comprising: a vessel, a first downcomer, an outer fluid supply downcomer and structure defining an insulating region between the first and outer downcomers. The first downcomer extends into the vessel for delivering a first fluid into the vessel. The first fluid is generally at a first temperature when passing into the first downcomer. The outer fluid supply downcomer extends into the vessel and may be located about the first downcomer for supplying a second fluid into the vessel. The second fluid may be generally at a second temperature different from the first temperature when passing into the outer downcomer. The structure defining an insulating region between the first and outer downcomers functions to reduce heat transfer between the first and outer downcomers.

Abstract: An in-line drainer or liquid separator for draining liquid from a moving black liquor slurry stream having a screen basket mounted in the internal chamber of the in-line drainer. The screen basket includes slots to retain solid particles of the moving black liquor slurry stream within the black liquor slurry stream flow chamber and block the solid particles from entering the liquid collection chamber. The slots each have a curved corner edge adjacent a surface screen basket facing the black liquor slurry stream flow chamber.

Abstract: The feed system is for a continuous digester where at least two pumps are arranged in parallel in the bottom of a pre-treatment vessel and a liquid level of at least 20 meters is established. The system makes it possible to provide a feed system with an improved accessibility and more reliable operation, and to operate the main part of the pumps at optimal efficiency even if the production capacity is reduced.

Abstract: The feed system is for a continuous digester where at least two pumps are arranged in parallel at the bottom of a pre-treatment vessel and a stirrer is provided in direct connection to inlets to pumps. The system makes it possible to provide a feed system with an improved accessibility and operational reliability, and to operate the main part of the pumps at optimal efficiency even if the production capacity is reduced.

Abstract: A method of pre-treating a cellulosic material before hydrolysis is provided. The method comprises the steps of: impregnating the cellulosic material with a reactive water-soluble gas, such as sulphur dioxide (SO2) or carbon dioxide (CO2), in an impregnation chamber to obtain impregnated material; and heating the impregnated material to obtain pre-treated material, wherein the cellulosic material is compressed right before or when it is transferred to the impregnation chamber. A corresponding system is also provided.

Abstract: A reactor vessel including: an upper inlet and a bottom discharge; a generally vertically oriented sidewall between the upper inlet and bottom discharge, wherein the sidewall defines a perimeter of an interior flow passage in the vessel; a first pair of support plates arranged on opposite sides of the sidewall, wherein the first pair of support plates reduces a cross-sectional flow area of the flow passage in a first single direction of convergence, and a second pair of support plates arranged on opposite sides of the side wall, wherein the second pair of support plates reduces a cross-sectional flow are of the flow passage in a second single direction of convergence, wherein the second single direction is angularly offset to the first single direction, and the second pair of support plates is at a different elevation of the vessel than the first pair of support plates.

Abstract: The feed system is for a continuous digester where at least two pumps are arranged in parallel in the bottom of a pre-treatment vessel and a liquid level of at least 10 meters is established. The system makes it possible to provide a feed system with an improved accessibility and more reliable operation, and to operate the main part of the pumps at optimal efficiency even if the production capacity is reduced.

Abstract: The feed system is for a continuous digester where at least two pumps are arranged in parallel at the bottom of a pre-treatment vessel. The transfer to the top of the digester takes place without a conventional top separator. The system makes it possible to provide a feed system with an improved accessibility and operational reliability, and to operate the main part of the pumps at optimal efficiency even if the production capacity is reduced.

Abstract: The feed system is for a continuous digester where at least two pumps are arranged in parallel at the bottom of a pre-treatment vessel and a stirrer is provided in direct connection to inlets to pumps. The system makes it possible to provide a feed system with an improved accessibility and operational reliability, and to operate the main part of the pumps at optimal efficiency even if the production capacity is reduced.

Abstract: The feed system is for a continuous digester where at least two pumps are arranged in parallel at the bottom of a pre-treatment vessel. Each pump has its own independent transfer line extending to the top of the digester. The system makes it possible to provide a feed system with an improved accessibility and operational reliability, and to operate the main part of the pumps at optimal efficiency even if the production capacity is reduced.

Abstract: The feed system is for a continuous digester where at least two pumps are arranged in parallel at the bottom of a pre-treatment vessel. The outlets of the pumps are combined at a merging point before a common transfer line extends to the top of the digester. The system makes it possible to provide a feed system with an improved accessibility and operational reliability, and to operate the main part of the pumps at optimal efficiency even if the production capacity is reduced.

Abstract: The withdrawal screen section is for impregnation of chips during the manufacture of chemical pulp. Chips are steamed and impregnated in a low pressure impregnation vessel using pressurised hot spent cooking liquor BL. The spent cooking liquor produces most of the steam BLST, necessary for steaming the chips. To reduce the need for adding fresh steam for chip steaming is a first withdrawal section in the impregnation vessel modified to be used both as a flash tank for warm pressurised wash filtrate and improved wash-out feature for the spent impregnation liquid behind the screen in the withdrawal section. The withdrawal volume is arranged with an upper part located above the liquid level LIQLEV of the impregnation vessel. Additional pressurised warm wash liquor REC1 is added to the withdrawal volume and flashed off steam is led in a steam duct to the chip volume above the liquid level.

Abstract: The method and an arrangement are for the improvement of a wash after completed digestion in a continuous digester for the production of cellulose pulp. The softened chips are exposed to a radially directed displacement wash after they have passed the rotating bottom scraper. The displacement wash has been established in the flow of digested softened chips through the outlet tap before the softened chips are defibrated by the fall in pressure across the blow-valve that is arranged after the digester.

Abstract: Digested softened non-defibrated chips are fed out from a bottom of a digester. The chips are fed out under an influence of a bottom scraper at the bottom of the digester and through an outlet tap at the bottom of the digester and onwards to an outlet line connected to the outlet tap. This takes place before the softened chips pass through a blow-valve arranged in the outlet line, across which blow-valve a pressure drop of at least 0.5 bar and at most 3-5 bar has been established. The chips are exposed to a displacement wash after the chips have passed the outlet tap. The displacement wash has been established in the flow of chips through the outlet line before the chips are defibrated by the pressure drop across the blow-valve.

Abstract: Apparatus for screening cellulose pulp streams is disclosed including first and second screens contained in a housing, and a primary inlet for directing the cellulose pulp stream into the housing, an accept outlet for withdrawing an accept portion from the housing, a reject outlet for withdrawing a reject portion from the housing, a first accept chamber for receiving the accept portion which has passed through the first screen, a second screen chamber for directing the first accept portion to the second screen, and a secondary pulp inlet for receiving a second cellulose pulp feed stream comprising a screened cellulose pulp accept fraction and directing it to the second screen whereby the second accept fraction is delivered to the accept outlet. Methods and systems for screening cellulose pulp systems are also disclosed.

Abstract: A pulp cooking system including: a cellulosic material feed system, a pre-hydrolysis reactor vessel and a Kraft cooking reactor vessel. The feed material system includes a steaming chip bin and a high pressure transfer device. The pre-hydrolysis reactor vessel maintains the feed material in a mildly acidic condition and allows hydrolysate to be extracted through screens below a hydrolysis zone in the vessel. A wash zone is below the screens and allows wash liquid to flow through the feed material in a cross-current direction. The wash liquid and hydrolysate removed from the feed material is extracted through the screens. The feed material is maintained in a mildly acidic condition through the pre-hydrolysis reactor vessel until the material enters the Kraft cooking vessel where the feed material is treated with alkaline cooking liquors.

Abstract: A method of and an apparatus for processing cellulose pulp of wood processing industry. The method and assembly may be used, on one hand, as a pressure diffuser for washing the pulp before an oxygen stage and, on the other hand, the separation of soap, gas and/or other light materials from filtrates and from black liquor of a cellulose mill in a pressurized device, as well as the new process connections enabled by the method. The method and apparatus may process filtrates from brown stock washing and bleaching as well as black liquors from a digesting department and an evaporation plant. By way of example, the filtrate of the washing department is pumped to the digesting department of a sulfate cellulose mill as well as the black liquor taken from the digesting department to an evaporation plant.

Abstract: The system and method reduce the liquid/wood ratio at the top of a vapor phase digester in a continuous digester plant. Chips that are to be cooked in the vapor phase digester are fed as a mixture of chips and liquid at a liquid/wood ratio that exceeds 8:1 in a transfer line to an inverted top separator arranged at the top of the vapor phase digester. The top separator feeds the chips upwardly. More than 50% of the liquid content of the mixture of chips and liquid is withdrawn in the top separator and the remaining liquid is fed out from the top separator to the top of the vapor phase digester. A pile of chips and a liquid volume are established at the top, wherein the pile of chips is disposed above the liquid surface of the liquid volume.

Abstract: A system has been developed for pretreating cellulosic biomass feed stock including: a first pressurized reactor receiving the feed stock, wherein the feed stock undergoes hydrolysis in the first pressurized reactor; a sealing device having a first pressurized coupling to a feedstock discharge port of the first pressurized reactor, and a second pressurized coupling to a second pressurized reactor; a drain for a liquid including dissolved hemi-cellulosic material extracted from the feed stock in at least one of the first pressurized reactor and the sealing and extraction device; the second pressurized reactor assembly receiving the pressurized feed stock from the sealing device at a pressure substantially greater than the pressure in the first pressurized reactor, wherein cells of the feed stock are infused with water in the second pressurized reactor, and an expansion device downstream of the second pressurized reactor assembly, wherein the expansion device rapidly releases the pressure of the feed stock disc

Abstract: A method for the impregnation of untreated chips during the manufacture of chemical pulp. The untreated chips are fed without preceding steam treatment into an impregnation vessel that has an upper part with a first area (A1) and a lower part with a second area (A2) that is larger than the first area (A1) by a factor of at least ?{square root over (2)}. The chips establish in the upper part a level of chips that is located at a level (h) above a level of fluid consisting of liquor. The chips after passage of the upper part pass through a transitional part, where an increase in area from the first area (A1) to the second area (A2) takes place, and it is here that the angle of repose of the chips is reduced.

Abstract: A hinge is mounted between a cover and a base of an electronic device. A lid covers the hinge and is attached securely to the base. The hinge has an arced surface and a rotating shaft. When the cover is pivoted to a certain angle, the rotating shaft abuts the arced surface to lift up the cover so the cover is selectively distant away from the lid. Therefore, the shape of the electronic device does not need to be disfigured and the cover still does not bump against the lid.

Abstract: A screen for the screening of pulp suspensions is disclosed, including a screen basket, a rotor for providing pressure and suction pulses in the suspension to be screened along the screen basket, and a dilution liquid header for supplying dilution liquid to counteract thickening of the suspension during operation. The header forms a tubular channel, which divides the screen basket into at least two parts, extends around the basket, and is provided with a plurality of dilution ejection nozzles. Each ejection nozzle forms a channel including at least two channel sections; namely, an entrance channel section that opens into the channel of the header, and an exit channel section downstream of the entrance channel section, wherein the entrance channel section is substantially wider than the exit channel section.

Abstract: In a continuous digester system the digester system is greatly simplified by using a single vertical atmospheric vessel, replacing the conventional chip bin, steaming vessel, chip chute, high pressure pumping or sluice feeders, impregnation vessels and top separator. Chips are simply fed to the top of the atmospheric vessel, and a chip level is established in the vessel. Treatment liquids are added to the vessel such that a total liquid volume (Z1+Z2) with a liquid level (LIQ LEV) is established under the chip level (CH LEV). Impregnation stage and subsequent cooking stages are implemented in the atmospheric vessel at successively increasing temperature and depths into the total liquid volume, thus preventing boiling in the stages and preferably reducing steam blow trough of the chip surface in the top of the vessel.

Abstract: A feed system for a comminuted cellulosic material including: a chip bin having an upper chip inlet, an interior chamber oriented generally vertically and a lower discharge port; at least one liquor inlet to the chip bin to inject liquor in the chip bin, wherein the chip bin retains sufficient liquor and chips within the interior chamber to create a hydraulic pressure on the chips at the lower discharge port; a generally horizontally oriented chip conveyor or tube coupled to the lower discharge port to receive the chips and liquor from the bin under the hydraulic pressure, wherein the conveyor or tube includes liquor injectors which inject liquor into the chips and the conveyor or tube, and a high pressure transfer device coupled to a discharge of the conveyor or tube to receive the chips and liquor, whereby the hydraulic pressure of the chips and liquor at the discharge of the chip bin is sufficient to feed the chips and liquor to the high pressure transfer device.

Abstract: An outlet device and motor assembly for a pressured vessel is disclosed, where the assembly includes: a generally vertical drive shaft extending below and through the vessel and coupled to a rotating mechanism within the vessel; a stationary outlet housing supporting the drive shaft; a thrust bearing mounted on the outlet housing and around the drive shaft to rotationally engage the drive shaft; a hydraulic drive coupled to rotationally drive the drive shaft, and a radial bearing mounted around the drive shaft to rotationally engage the drive shaft and said radial bearing is at or below the hydraulic drive.

Abstract: A screen plate for a cellulosic material puling vessel, the screen plate including: slots having curved inlet corner edges adjacent an inside surface of the screen plate and facing a pulp flow.

Abstract: A continuous digester comprises a wash zone having a plurality of individual wash screens disposed about an inner wall of the digester for the withdrawal of co-current downflow liquor from the wash zone. A conduit is connected in fluid communication between each of the wash screens and a collector for co-current downflow liquor withdrawn from the wash zone of the digester. A valve is interposed along the length of the conduit leading from each of the wash screens. The valve is operable between open and closed positions in response to a signal received from a temperature sensor associated with the conduit leading from each of the wash screens.

Abstract: The method and arrangement is for the feed of a chips suspension from one vessel to a subsequent digester in a continuous cooking process for the production of chemical cellulose pulp. The vessel has an inlet defined therein for the input of chips and an outlet defined therein for the output of a chips suspension. The chips suspension in the vessel has a first fluid/wood ratio established above a second fluid/wood ratio that is established at the bottom of the vessel. The second fluid/wood ratio is at least as great as, preferably greater than, the first fluid/wood ratio. After the output of the chips suspension from the vessel and before the chips suspension is placed under pressure for onwards transport to a subsequent digester, a fraction of fluid is withdrawn from the chips suspension, whereby a third fluid/wood ratio is established in the chips suspension.

Abstract: A method for converting a vapor phase continuous digester to a hydraulic digester including the steps of: operating the vapor phase digester in a vapor phase mode wherein a chip slurry enters the vessel of the digester through a lower chip inlet port, moves up through a top separator, discharges from an upper chip discharge chute of the separator to an upper vapor region of the vessel and falls to a liquor filled region of the vessel; ceasing the flow of the chip slurry to the separator; establishing a chip slurry flow path to an upper portion of top separator, and filling the vessel with liquor and chips such that the chip discharge chute is immersed in liquor.

Abstract: A continuous digester comprises a wash zone having a plurality of individual wash screens disposed about an inner wall of the digester for the withdrawal of co-current downflow liquor from the wash zone. A conduit is connected in fluid communication between each of the wash screens and a collector for co-current downflow liquor withdrawn from the wash zone of the digester. A valve is interposed along the length of the conduit leading from each of the wash screens. The valve is operable between open and closed positions in response to a signal received from a temperature sensor associated with the conduit leading from each of the wash screens.

Abstract: An apparatus and method serves, e.g., to deaerate, clean or screen a fibrous suspension and is provided with a closed housing and a rotor arranged centrally therein. The rotor puts at least a part of the fibrous suspension guided into the housing into a rotational flow. The fibrous suspension flowing into the housing through the inlet is put into rotation by a guide element acting hydraulically. This increase the efficiency of the apparatus and prevents disturbing turbulences in the apparatus.

Abstract: The arrangement concerns an improved design for at least one of the cooling, dilution and washing at the bottom of a continuous digester for the production of cellulose pulp. By arranging at least one extra strainer section above the lowermost strainer section, with the addition of washing fluid or dilution fluid between the extra strainer section and the lowermost strainer section, more washing fluid can be added at the bottom of the digester without counteracting the flow of the column of chips. This provides space for the increase of production, for improvement of the flow of the column of chips, or for combinations of these effects while retaining good cooling, washing and dilution at the bottom of the digester.

Abstract: A method for feeding a cellulosic fibrous material to a high pressure processing vessel including: pressurizing a low pressure flow of the fibrous material in a high pressure transfer device; discharging a high pressure flow of the fibrous material from the transfer device to a conduit in fluid communication with the processing vessel; discharging a low pressure flow of fluid and fibrous material from the transfer device; downstream of the transfer device, pressurizing the discharged low pressure flow; merging the pressurized low pressure discharge flow with the discharged high pressure flow, and transferring the merged flow to the processing vessel.

Abstract: A fluid transfer apparatus for bulk material is disclosed. The transfer apparatus includes a rotor mounted on a rotatable shaft and including axially extending flow channels extending through the rotor parallel to the shaft, flow connectors for connecting a low-pressure flow of fluid and a high-pressure flow of fluid into and out of the axially extending flow channels, a casing enclosing the rotor, a pair of axially sealing plates disposed between the ends of the rotor and the casing, a pressurizing fluid fed into the chamber defined by the casing to pressurize the rotor, the flow connectors, and the axially movable sealing plates.

Abstract: A method and an apparatus for processing wood chips, wherein the wood chips are treated with steam in a gas removal apparatus. The condensate formed in the gas removal apparatus is removed from the gas removal apparatus and the wood chips are treated with a processing solution in order to remove metal ions from the wood chips. Condensate formed in the gas removal apparatus is used as processing solution.

Abstract: The arrangement concerns an improved design for at least one of the cooling, dilution and washing at the bottom of a continuous digester for the production of cellulose pulp. By arranging at least one extra strainer section above the lowermost strainer section, with the addition of washing fluid or dilution fluid between the extra strainer section and the lowermost strainer section, more washing fluid can be added at the bottom of the digester without counteracting the flow of the column of chips. This provides space for the increase of production, for improvement of the flow of the column of chips, or for combinations of these effects while retaining good cooling, washing and dilution at the bottom of the digester.

Abstract: Screening apparatus for screening pulp suspensions is disclosed comprising a screen basket dividing the interior of the housing into a central chamber and a single outer annular chamber. The suspension is supplied to one of the outer and central chambers, so that an accept fraction passes through the screen, while a reject fraction develops that is prevented from passing through the screen. Dilution is provided by supplying diluting liquid to dilute the reject fraction. The screen basket is divided into at least two separate tubular screen sections. The dilution is provided by at least one annular element axially interconnecting the two tubular screen sections and forming a tubular dilution liquid compartment extending at least substantially around the screen basket. The annular element forms a plurality of dilution liquid ejection passages between the dilution liquid compartment and one of the outer and central chambers.

Abstract: This is a device and a method for withdrawing cellulose pulp with a pulp concentration of 8-14% from a cylindrical storage tower. The storage tower has a plane bottom and with a diameter that exceeds 3 meters. A pipe is arranged through the wall of the storage tower that is parallel to the bottom of the tower and directed towards the center of the tower. The pipe has at one of its ends an obliquely cut opening that faces upwards in the tower. The pipe is attached at its other end to an MC pump to be able to pump out cellulose pulp from the storage tower.

Abstract: A method for adding cooking liquor into a vapor phase continuous digester for producing chemical cellulose pulp from cellulose chips including: introducing a slurry of the cellulose chips from a feed system to an inverted top separator in a top vapor phase section of the digester; distributing the slurry of the cellulose chips from the top separator into the vapor phase section of the digester; passing liquor through a conduit included with the drive shaft assembly of the top separator, and introducing the liquor from the conduit into the slurry as the slurry flows through the top separator or is distributed from the separator into the vapor phase section.

Abstract: This invention is directed to a method for cooking wood chips in a digester for the separation of wood fibers from their bonded state, the digester having a vertical centerline, a substantially circular cross-section, and a wash zone adjacent the bottom end thereof and a plurality of individual wash screens disposed about the inner wall of the digester for the withdrawal of liquor from the wash zone. In the first step of the method, substantially equal volumes of liquor are dynamically withdrawn from the wash zone through individual ones of the wash screens, while monitoring of the flow rate of liquor exiting the digester through individual ones of the wash screens. The monitored flow rate is used to increase or decrease the flow rate from screens to a value substantially equal to the flow rate of liquor from the digester through each of the screens.

Abstract: Method and apparatus for introducing liquors into a batch digester to produce enhanced or plug-flow of the liquors through the bed of cellulosic material. Wash out liquor can be introduced into the digester during the discharging of delignified cellulosic material in a manner to add wash out liquor into the digester in order to maintain consistency of the delignified cellulosic material and to prevent formation of a vortex of delignified cellulosic material during discharge.

Abstract: An outlet device and motor assembly for a pressured vessel is disclosed, where the assembly includes: a generally vertical drive shaft extending below and through the vessel and coupled to a rotating mechanism within the vessel; a stationary outlet housing supporting the drive shaft; a thrust bearing mounted on the outlet housing and around the drive shaft to rotationally engage the drive shaft; a hydraulic drive coupled to rotationally drive the drive shaft, and a radial bearing mounted around the drive shaft to rotationally engage the drive shaft and said radial bearing is at or below the hydraulic drive.

Abstract: A method and apparatus for treating pulp in connection with a blow tank or a storage tank. The pulp is discharged from a batch digester and fed either to the upper or the lower part of a blow tank, depending on the consistency of the pulp being discharged from the digester.

Abstract: The method and an arrangement are for improved impregnation of chips in association with the manufacture of chemical cellulose pulp. Un-steamed chips are fed into an impregnation vessel (30) in which a fluid level (LIQ_LEV) is established under the highest level (CH_LEV) of the chips. An improved impregnation arrangement for the chips is obtained by the addition of impregnation fluids (BL1/BL2/BL3) with increasing temperatures at different heights (P1, P2, P3), and by the establishment of a counter-flow zone (Z1) in the uppermost part of the impregnation vessel. The requirement for steaming may in this way be dramatically reduced while at the same time the amount of expelled waste gases may be minimized. A major part of the volatile compounds present in the wood are bound to the impregnation fluid (REC) that is withdrawn.

Abstract: Countercurrent extraction of lignocellulosic biomass such as trees, grasses, shrubs, and agricultural residues or waste involves the separation of cellulose fibers from other constituents, for subsequent use in the manufacture of paper, plastics, ethanol, and other industrial chemicals. Systems and methods involve continuous, multiple processing steps that may include chemical reactions with mixing at elevated temperature and/or pressure, efficient reagent or solvent utilization, filtration at elevated temperature and/or pressure, controlled discharge of liquid and solid products, and energy recuperation.

Abstract: A continuous digester for producing chemical cellulose pulp from cellulose chips including: a digester vessel with an upper section attached to a top separator and said vessel at least partially filled with the cellulose chips and a liquor; a top separator at least partially in said upper section having a lower chip inlet port, a chip conveyor, a screen adjacent the conveyor, an upper chip discharge chute, and a liquor outlet facing a side of the screen opposite to the conveyor, and a chip inlet conduit extending into the vessel and having a first operational mode in fluid communication with the chip inlet port and a second operational mode in which the chip inlet conduit discharges directly into the vessel.