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 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: Provided is a lignocellulosic biomass saccharification pre-treatment device capable of producing a pretreated material for saccharification. The lignocellulosic biomass saccharification pre-treatment device comprises a separation unit 4 which separates ammonia gas by heating a pretreated material for saccharification obtained from a substrate mixture obtained by mixing lignocellulosic biomass and ammonia water; a first heat recovery unit 25 which recovers heat-of-dissolution generated when ammonia gas is dissolved in water, and the heat supply units 8, 9, 10 which generate heat by using heat-of-dissolution recovered by the frst heat recovery unit 25 and supply the heat to the separation unit 4.

Abstract: To provide an apparatus for pretreatment for saccharification easily and continuously applying a treatment and capable of reusing ammonia at low cost. The apparatus has a mixing unit 2, a first heating unit 3, a separation unit 4, a transfer unit 6, an ammonia water supply unit 8 and an ammonia recovery unit 19. The apparatus may have the first heat exchanger 18, a second heat exchanger 25 and a heat supply unit 27 and further has a second heating unit 14. The apparatus may have a wet grinding unit 32 between the heating unit 3 and 25.

Abstract: An apparatus is provided for digesting samples. The apparatus includes a vessel, a closure, and a fluid transporting system. The vessel has a digestion chamber therein that contains a sample holder, e.g., with a plurality of weights, the holder being accessible through a vessel opening. Typically, a vessel flange circumscribes the chamber at the chamber's opening, and the closure has a closure flange that may interface with the vessel flange to form a fluid-tight seal against a digestion pressure and temperature within the chamber. The fluid-transporting system may direct digestion fluid out of the digestion chamber through a submerged outlet port and back into the digestion chamber through an inlet port that traverses through the closure or the vessel flange. Such a fluid transporting system may be set up to allow the sample holder have a high volumetric capacity, e.g., at least 75% of the chamber.

Abstract: To provide an apparatus for pretreatment for saccharification easily and continuously applying a treatment and capable of reusing ammonia at low cost. The apparatus has a mixing unit 2, a first heating unit 3, a separation unit 4, a transfer unit 6, an ammonia water supply unit 8 and an ammonia recovery unit 19. The apparatus may have the first heat exchanger 18, a second heat exchanger 25 and a heat supply unit 27 and further has a second heating unit 14. The apparatus may have a wet grinding unit 32 between the heating unit 3 and 25.

Abstract: A chemical pulp mill system and method of using black liquor flashing steam from a digester system comprises generating black liquor in the digester system, sending the black liquor to an evaporator system without using any pre-evaporator system, flashing the black liquor in the evaporator system to yield steam, and using at least some of the steam for chip steaming in a chip bin and/or for supplying in-direct heat exchangers in the digester system for pre-heating white liquor and/or filtrates for use in the digester system.

Abstract: A method to cook thin chips in a continuous digester vessel including: introducing thin chips having a thickness of no more than 6 mm, into a chip bin; adding white (cooking) liquor to the chip bin or to a chip transport passage extending from the chip bin to an upper inlet of the continuous digester vessel; injecting medium pressure steam or another heated fluid to an upper region of the digester vessel to elevate a cooking temperature of the chips in the vessel to at least 130 degrees Celsius; cooking the chips in the vessel as the chips flow downward through the vessel without substantial extraction or introduction of liquor in the cooking section of the vessel; injecting wash liquid to a lower region of the vessel; extracting at least wash liquid through a wash liquid extraction screen in the lower region of the vessel and above the injection of the wash liquid, and discharging the cooked thin chips from the lower region of the vessel.

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: Provided is an apparatus for digesting cellulosic material that includes a vessel containing a digestion chamber and having an opening that provides access to the digestion chamber. A container for holding the cellulosic material is located within the digestion chamber. A closure interfaces with the vessel opening to form a seal against a predetermined digestion pressure and temperature within the chamber. A fluid-transporting system directs digestion fluids from a supply in the digestion chamber through a port and the container toward any cellulosic material therein. Digestion fluid distributed from the port through the container soaks the cellulosic material. Also provided are processes for digestion cellulosic material.

Abstract: A method for heating white liquor or a mixture of white liquor and another liquid for use in a digester system of a chemical pulp mill, the method including the steps of: producing black liquor in the digester system; extracting black liquor from the digester system, flashing the extracted black liquor and thereby generating flashed black liquor and flash vapor; directing the flash vapor through a heat exchanger to heat a white liquor flowing through the heat exchanger; the flashed black liquor flows to at least one of a heat recovery or evaporation stage, and the heated white liquor flows to the digester system.

Abstract: A method for impregnating chips in a continuous digestion system with an impregnation vessel and a digester. The digestion system has a heat exchanger arranged between a first return line and a black liquor line. The heat exchanger allows a transfer of heat between the two lines. A principal part of the fluid contents of the impregnation vessel is constituted by chips moisture, steam condensate, added white liquor, and the fluid withdrawn from the top separator at the first return line, whereby the impregnation fluid in the impregnation vessel does not contain any substantial amount of black liquor from the digester. An impregnation vessel is established that is hydraulically isolated, in which the flow of fluid and the establishment of its alkali content take place without any influence from the fluid flow in the digester process.

Abstract: Provided is an apparatus for digesting cellulosic material that includes a vessel containing a digestion chamber and having an opening that provides access to the digestion chamber. A container for holding the cellulosic material is located within the digestion chamber. A closure interfaces with the vessel opening to form a seal against a predetermined digestion pressure and temperature within the chamber. A fluid-transporting system directs digestion fluids from a supply in the digestion chamber through a port and the container toward any cellulosic material therein. Digestion fluid distributed from the port through the container soaks the cellulosic material. Also provided are processes for digestion cellulosic material.

Abstract: A method for producing paper pulp from a lignocellulosie vegetable raw material. The method includes contacting the raw material with a mixture of formic acid and acetic acid (in an amount more than 5 wt. % of the mixture) at a temperature and for a suitable reaction time, the whole being performed at room temperature. The paper pulp is separated from the organic phase and optionally bleached with ozone. The organic phase is treated to enable the recycling of the formic and acetic acids and the extraction of lignins, sugars and excess acetic acid.

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: A continuous pulp digester having an elongate horizontally aligned pressure vessel through which the wood chips and digesting fluid flow in a forward direction. In a first and second embodiments within the pressure vessel there is an inner container defining an elongate chamber or passageway having a square cross sectional configuration. In a third embodiment the digesting chamber is cylindrical. At locations along the digester, there are several pair of liquid flow inlets and liquid flow outlets which enable filtrate from a pulp washer and a digesting agent to be moved into and across the digesting chamber to flow out the flow outlets. These are recirculated in a net upstream flow pattern toward the outlet end of the digester, and discharged as black liquor at different locations in the digester.

Abstract: A pre-treatment device for wood chips for pulping comprises a tube through which the wood chips fall into a digester. Steam is injected into the tube through rings of nozzles, which are angled circumferentially to impart a rotary and turbulent motion to the falling chips. Some nozzles are angled downwardly to encourage the chips to flow freely through the tube, some are horizontal to encourage a longer dwell time near the nozzles. Digesting liquor is also sprayed onto the chips from spray nozzles after the first ring of steam nozzles. The heat and steam expel air and other non-condensable gases and volatiles from the chips, allowing them to absorb the liquor. At the bottom of the tube, the chips are propelled down and outwards by jets of higher-pressure steam, spreading and packing them into the digester.

Abstract: A method to remove scale build-up in a vessel having at least one screen is described and involves placing a cover inside the vessel such that it is located beneath at least one screen to separate the screen from the rest of the vessel. The cover in the vessel forms an upper portion and a lower portion in the vessel. Preferably, the cover is in close proximity to the screen which is located in the upper portion of the vessel. The method then further includes introducing a chemical formulation into the upper portion of the vessel in a sufficient amount to remove at least a portion of the scale build-up on the screen. A system to remove scale build-up is also described and includes a vessel having at least one screen. The system further includes a cover located inside the vessel and beneath at least one screen to separate the screen from the rest of the vessel and to form an upper portion and a lower portion in the vessel. Normally the cover is in close proximity to the screen.

Abstract: A system and method for feeding comminuted cellulosic fibrous material such as wood chips to the top of a treatment vessel such as a continuous digester provide enhanced simplicity, operability, and maintainability by eliminating the high pressure transfer device conventionally used in the prior art. Instead of a high pressure transfer device the steamed and slurried chips are pressurized using one or more slurry pumps located at least thirty feet below the top of the treatment vessel and for pressurizing the slurry to a pressure of at least about 10 bar gauge. A return line from the top of the digester may, but need not necessarily, be operatively connected to the one or more pumps and if connected to the pumps, the liquid in the return line may be cooled to a temperature at which it will not flash during handling. Recirculation loops may be established associated with one or all of the slurry pumps to facilitate startup.

Abstract: Chemical cellulose pulp is made from sawdust utilizing a static down-flow retention vessel. By adding steam and cooking liquor to a flow of sawdust a heated slurry, at a cooking temperature of about 250-350° F., is produced. The heated slurry is, at superatmospheric pressure, moved downwardly in the static down-flow retention vessel while cooking temperature is maintained, for a time period of about 0.5-6 (preferably 1 to 3) hours, the slurry having a consistency of about 5-30%. At superatmospheric pressure, without significant reduction in pressure from the retention vessel, the slurry is cooled to well below cooking temperature by diffusing cooling liquid through it, as in a conventional pressure diffuser. The discharge from the retention vessel is preferably substantially solely gravity action (e.g. using a discharge with single convergence and side relief).

Abstract: A method and apparatus for heating cellulose pulp with steam are provided. Low-pressure (e.g. 3-5 bar (abs.)) steam is supplied into the pulp flowing as a plug flow in such a way that in the flow direction of the pulp, before supplying the low-pressure steam, the pulp is pressurized so that the pulp pressure at the point of the steam introduction is lower than the pressure of the available steam. After the steam is introduced the pulp is mixed with a pressure-raising mixer (such as a fluidizing centrifugal pump) to divide the steam evenly into the pulp and/or to equalize the temperature of the pulp.

Abstract: Yield, particularly when treating hardwood chips, can be improved by at least 1-2% in a kraft cellulose pulping process by keeping the temperature and effective alkali (EA) low during impregnation, and by keeping the EA low in at least a first cook stage. After cooking, the pulp is subjected to cooling low EA liquor, e.g. to reduce its temperature to below 120° C. (preferably below 100° C.) with an EA below about 5 g/L (expressed as NaOH). Continuous treatment in a continuous digester system is preferred, with the EA below about 20 g/L during impregnation and the first cook.

Abstract: Steam (preferably clean steam) having less noncondensible gases than steam produced by conventional black liquor flashing is produced from hot black liquor from a digester of a pulp mill. A heat exchanger is utilized and the hot black liquor is passed through the heat exchanger in heat exchange contact with an evaporable liquid, preferably clean water. After the water is heated in the heat exchanger it is flashed in at least one flash tank where the heat exchanger is a liquid-to-liquid heat exchanger. The heat exchanger may alternatively include an evaporator (such as a falling film evaporator) in which case the black liquor is passed through an inductor before it enters the evaporator. Alternatively, the heat exchanger may be one or more boilers, such as kettle boilers, in which case the black liquor preferably passes through a cooler after the boilers. Heat energy and turpentine recovery are also maximized.

Abstract: Useable steam, e.g. substantially clean useable steam, is produced from a chemical cellulose pulping system hot spent treatment liquor (e.g. black liquor) with optimum energy efficiency by passing the spent liquor to a reboiler, and then pressurizing (e.g. with an eductor, fan, or compressor) the clean steam discharged from the reboiler. The clean steam can be used to steam incoming chips (e.g. in a chip bin) without significantly increasing the TRS load on the pulp mill NCG system.

Abstract: A chip bin for wood chips in a continuous digester system includes internal steaming that is controlled in response to both the interior temperature across the level of chips in the bin, and the level of chips in the bin, so as to substantially prevent cool, non-condensible gas-laden chips from accumulating at the top of the chip column in the bin, and to substantially prevent steam blow-through. The temperature probe used in the chip bin has a temperature sensing portion with a length of about ten to twenty feet instead of the conventional five foot length, and extends across the level of the chips to a position about five feet below the level of chips. Control of steam added to the bin is provided utilizing a controller which controls the position of one or more valves in one or more steam conduits, each valve having multiple open positions and a closed position.

Abstract: A chip bin construction, ideally suited for bins having a maximum diameter of twelve feet or more, uniformly discharges chips, after steaming, without the necessity of a vibratory discharge. A hollow transition portion is provided between a hollow substantially right circular cylindrical main body and a rectangular discharge. The hollow transition may have a substantially circular cross-section open top and a substantially rectangular cross-section open bottom and opposite non-vertical gradually tapering side walls. At least one feed screw may be mounted at the open bottom of the transition for cooperation with the discharge, and the feed screw(s)--or the equivalent--may provide for metering of the chips. Alternatively, the hollow transition portion may provide one dimensional convergence and side relief, and no screw feeders need be provided, in which case a conventional chip meter is used.

Abstract: Kraft pulp of increased strength (e.g. at least about 15% greater tear strength at a specified tensile for fully refined pulp, and as much as about 27%) is produced by keeping the dissolved organic material (DOM) concentration below about 100 g/l (e.g. <50 g/l) throughout substantially the entire kraft cook. This may be done by extracting liquor containing a level of DOM substantial enough to adversely affect pulp strength, and replacing some or all of the extracted liquor with liquor containing a substantially lower effective DOM level than the extracted liquor, so as to positively affect pulp strength. The replacement liquor may be water, white liquor, pressure heat treated black liquor, washer filtrate, cold blow filtrate, or combinations, or the extracted liquor can be treated to remove or passivate the DOM (e.g. by precipitation, ultrafiltration, or absorption).

Abstract: Apparatus is disclosed for heating cellulosic pulp in a pipe including fittings mounted on the outer surface of the pipe, and steam pipes connected to the fittings to supply steam thereto, the pipe including a number of apertures at locations corresponding to the fittings so that the steam can pass therethrough.

Abstract: An apparatus and method for treating cellulosic wood chips in a digestion process for the liberation of pulp in a caustic hydroxide solution at high pressures and temperatures by delivering preconditioned wood chips to a first chamber and circulating a low temperature black liquor through the chamber to preheat the chips, while continuously feeding the chips through the chamber to a second chamber at high temperature and pressure, circulating high temperature black liquor to the chips in the second chamber to advance them to cooking temperature, feeding white liquor and the chips to a digester for the digestion process over a predetermined period of time, and removing digested pulp and delivering the pulp to a washer with the black liquor for washing being utilized for the first chamber, and heating the white liquor through a heat exchange process with the high temperature black liquor.

Abstract: An apparatus for chemical treatment of lignocellulosic materials comprises two concentric compartments, the inner one is used for chemical reaction whereas the outer is used for generation of hot water or steam. The top and the bottom of the outer compartment is closed and connected to the inner one. These two are interconnected by two steam conduits. The inner compartment is also connected to a circulation pump and a heat exchanger. The bottom of this inner compartment is equipped with a quick-release valve which may be used to execute explosive discharge of the treated lignocellulosic material. On top of said apparatus is a cover which allows experiments to be performed under pressurized conditions. For experimentation, lignocellulosic material in form of chips (large particles) may be treated either with heated chemical solution or steam. Materials in form of fibers (fine particles) may be treated by means of vapor or by heat conduction furnished by the outer compartment.

Abstract: A two stage sulfonation system includes a mixing tank, a retention tank, a thickening press, a pressurized vessel, and a liquor recovery press in series relation. A sodium sulfite generation unit is connected to maintain a supply of sodium sulfite solution in a holding tank from which a controlled quantity of said solution is metered and injected in the mixing tank. Liquor extracted in the thickening press is cycled back to the mixing tank. Liquor extracted in the recovery press is moved to an intermediate tank and then transferred to the sodium sulfite generation unit, there fortified with fresh sodium sulfite and forwarded to the holding tank to maintain therein an appropriate supply to service the system. The system is designed to receive mechanical pulp, in a slurry form, first introduced into the mixing tank simultaneously with a metered charge of sodium sulfite solution from the holding tank, the sodium sulfite content of which is at a level from about 40 to about 200 g/l.

Abstract: The present invention relates to a method and apparatus for evaporating waste liquor produced when cooking fibrous material containing cellulose in a continuous pulp digester. In the continuous cooking process, fibrous material is heated to the process temperature by direct or indirect vapor heating in the digester at an increased pressure. The invention especially relates to digesters, in which fibrous material is heated directly with vapor.

Abstract: Wood chips, or like comminuted cellulosic fibrous material, are treated in a vertical presteaming vessel in the production of paper pulp. The vessel does not employ a vibrating discharge structure as is conventional, but rather utilizes as a discharge structure a plurality of rotating arms having depending blades, mounted at the bottom of the vessel, which force the wood chips toward a discharge opening in the vessel bottom. The steam is introduced into the vessel through a vertical tube concentric with the vessel, and surrounding a rotatable shaft which is connected to the arms of the discharge device. A truncated cone is provided at the bottom of the steam tube, making a slip connection with the tube, and overlies the discharge opening. The cone has maximum horizontal dimensions greater than those of the outlet, to cause the chips to move radially outwardly into contact with the discharge element.

Abstract: A system is provided to produce sugars from a liquid-solid mixture containing biomass, and an acid, wherein the mixture is heated to an appropriate temperature to achieve hydrolysis. The liquid-solid mixture is introduced as a stream into the circular-cylindrical chamber of a cyclone reaction vessel and steam is introduced to the vessel to provide the necessary heat for hydrolysis as well as to establish the liquid-solid mixture in a rotary flow field whereby the liquids and solids of the mixture move along spiral paths within the chamber. The liquid-solid mixture may be introduced at the periphery of the chamber to spiral down toward and be discharged at or near the center of the chamber. Because of differing mass, the solid particles in the mixture move radially inward at a different rate than the liquid and that rate is controlled to maximize the hydrolysis of the solids and to minimize the decomposition of sugars, thus formed.

Abstract: In a falling film exchanger, a screen arrangement for preventing solid particles in the liquid to be heated from plugging liquid distribution outlets of a perforated liquid distributing tray or reaching the heating surface of the heat exchanger.

Abstract: The present invention provides a reactor adapted to simultaneously accomplish chemical reactions and operations of size reduction of the solid materials in suspension and particularly for treatment in the cellulose and/or paper pulp industry. The reactor provides an essentially closed working environment and is provided in the lower part with a rotor which creates turbulence with flows over essentially the whole volume of the closed environment and is adapted to realize said conditions of the size reduction of solid materials with intimate mixing of same with the suspending liquid.

Abstract: A process for continuous digestion of wood chips which are passed through a heating zone, a digesting zone and a cooling zone in contact with cooking liquor is disclosed. In this process the wood chips are fed into and the liquid phase removed from the input end of the heating zone in such relative quantities that their heat-capacity flows are of approximately the same order of magnitude.

Abstract: A process and apparatus for producing pulp from impregnated cellulose-containing starting materials such as wood, straw, grass, waste materials etc. in a compacting apparatus comprising a shell (1) and two mutually opposite pistons (4, 4') contained in said shell. The material to be compacted is disposed between said pistons and constitutes a resistive electrical load. The pistons are movable relative to each other and the shell is movable relative to the pistons. The impregnated starting materials are digested at a relatively low hydromodulus of 0.5 to 2 with a direct action of heat on the impregnated starting materials in the compacting apparatus at a digesting temperature of 160.degree. to 300.degree. C. The digesting times are short and depend on the digesting temperature.

Abstract: A method and apparatus for selectively withdrawing liquor from digester cooking screens for controlling the temperature in continuous digesters. First and second pairs of screens, with cooperating headers, are provided, and first and second outlets spaced circumferentially around the digester are associated with each header. Each header provides a circumferential cavity free of dividing members. Within each pair of screens withdrawal is practiced so that each header is rested during each ultimate withdrawal step, and the side from which the liquor is drawn each successive withdrawal step that the same header is used is alternated. In practicing the invention, header blockage caused by deposited debris and scale is minimized and increased uniformity and improved product quality result.

Abstract: A versatile process and apparatus is presented for producing, in high yields, many different grades of pulp from a single wood specie or for pulping any specie or type of woody material, and for storage and recycling of the by-product liquid and gaseous materials. The process of this invention is virtually pollution free, and the reactant chemicals are recoverable from the by-products. In the alternative, the by-products themselves have a commercial value which may forestall recovery of the reactants. The lignin constituent extracted from the pulp is usable as a resin binder, a wood rehardening agent, or a glue.

Abstract: A pulping digester contains a liquid digesting medium and wood chips dispersed in the medium. The level of the wood chips in the digester is normally below the top of the digester. As chips and digesting medium are fed to the digester and as pulp and digesting medium are withdrawn from the digester, the chip level will vary dependent upon the net addition of chips and withdrawal of pulp. The variable location of the chip level, or chip height, is determined by positioning a temperature sensing means in the upper portion of the digester above the normally desired chip level. The temperature sensed by the sensing means is displayed to and monitored by the digester operator. As the chip level rises toward the temperature sensor, the sensed temperature will fall until the chip level rises above the location of the temperature sensor, after which the sensed temerature will rapidly increase as the chip level continues to rise above the location of the sensing means.

Abstract: A direct-steamed laboratory minidigester and a method of operating it are disclosed. This unit may be used to predict process parameters, e.g., yield and Kappa number, for operation of commercial direct-steamed digesters. Runs may be made rapidly and with small quantities of wood and chemicals. A plurality of units may be operated in parallel to generate replicate data points for statistical analyses or operated simultaneously, each under different conditions, to screen process variables, e.g., chemical charge, wood furnish, pressure, temperature, steam rate, and cooking time.

Abstract: A method for continuously digesting cellulosic fiber material so that the digested pulp has a very low quantity of reject material (i.e. one to two percent) compared to the prior art. Fiber material is continuously fed into a standing vessel downwardly through the vessel steam phase to establish a fiber level, digesting liquid being added to the vessel to maintain a liquid level therein, and the digested pulp being withdrawn from the bottom of the vessel. Spreading of the downwardly flowing fiber material in the steam phase substantially evenly over the vessel cross-section is effected and the downwardly flowing fiber material is heated by introducing a major portion of the steam to be introduced into the steam phase at a first vertical position about 0.0 to 100 cm. above the higher of the fiber and liquid levels in the vessel.Some of the steam may be added at a second vertical level, or at a third vertical level.

Abstract: Apparatus for the production of a lignocellulose material from chips, sawdust, chopped plants, bark, small fibres comprising a vertical column with a series of successively-mounted horizontal perforated plates partly abutting upon the inner surface of the column; at the free ends of said plates retaining baffles are secured for partial entrapment of coarse particles of the product; a clearance is provided between the baffle and inner surface of the column and the plates are disposed relative to each other so that baffles of each successive plate are located diametrically opposite to the baffles of each preceding plate thus forming a zigzag labyrinth along the total height of the column for increasing the time of contact of coarse particles of the raw materials with the oxygen-containing gas and alkaline reagent.A pulsator means is operably connected to the column for setting liquid reagents in the column into reciprocating vertical motion.

Abstract: A chips bin that allows thorough steaming of the chips in the bin without blockage of the chip flow. A chips bin with a vibrating discharge includes an activator cone and a number of support arms extending from the activator cone to the bottom portion of the bin. A number of steam ports are formed in each of the supporting arms and steam is introduced into the supporting arms and underneath the activator cone. The steam ports are formed in sidewalls of the supporting arms, and steam is introduced both underneath the bottom portion of the cone and underneath a top portion of the cone.

Abstract: A device for the counterflow treatment of fibrous deformable particles with liquid in stages in a tower. In the tower the particles and liquid flow downward by small movements and the liquid flows upwardly. Each of these successive two movements constitute one stage. The ascent of liquid alone, or filtration in each stage, is produced by introductions of water with adequate pressure through the bottom of the tower. The descent of the mass of particles and liquid or mass movement in each stage, is produced by rapid removal of mass from the lower part of the tower. During filtration periods, the particles suffer only small relative displacements among them, because the upper layer of the particles is retained by a screen, that only permits the flow of liquors; in addition, successive grids extending from the proximity of the screen to the proximity of the bottom of the tower, offer resistance to movement of the particles.