Abstract: Disclosed herein are methods, systems, and compositions for the uniform pretreatment of biomass within seconds with low inhibitor formation. The pretreatment process is used to convert biomass to a fuel, sugars, or other useful chemicals by subjecting the feedstock to a rapid retention time under pressure and temperature and/or chemical reactant. The system includes at least one high pressure, steam impermiable plug and a continuously-operating valve discharge apparatus to discharge pretreated feedstock while maintaining uniform pressure on the pretreatment system.

Abstract: The present invention is directed to an energy-efficient and environmentally friendly process for the production of chemical target compounds from cellulosic material. In a further aspect, the present invention is directed to a system for conducting the process according to the inventive process.

Abstract: A method to prepare, pulp, and bleach cannabis bast and hurd fibers to allow for the fiber to be incorporated into absorbent cellulosic structures on a wet-laid paper machine while keeping the pectin within the fibers. The wet laid paper machine can use the ATMOS, NTT, ETAD, TAD, or UCTAD method to produce the absorbent cellulosic structure. Absorbent cellulosic structures are produced with the cannabis bast and hurd fibers or with the bast fibers alone with the hurd fibers being combined with paper mill sludge or dust to form a fuel pellet.

Abstract: Nanocellulose-reinforced cellulose fibers can increase the strength of hardwood fibers or agricultural-residue cellulose fibers, to simulate the strength of softwood fibers in pulp or pulp products (including composites). In some variations, the invention provides a method of reinforcing cellulose fibers, comprising providing cellulose fibers derived from hardwoods, agricultural residues, or a combination thereof; providing a source of nanocellulose comprising cellulose nanofibrils and/or cellulose nanocrystals; and reinforcing the cellulose fibers with the nanocellulose to increase strength of the cellulose fibers. In some embodiments, the nanocellulose is obtained from fractionating biomass in the presence of an acid, a solvent for lignin, and water, to generate cellulose-rich solids and a liquid phase; and then mechanically refining the cellulose-rich solids to generate the nanocellulose.

Abstract: The present invention is directed to an energy-efficient and environmentally friendly process for the production of chemical target compounds from cellulosic material. In a further aspect, the present invention is directed to a system for conducting the process according to the inventive process.

Abstract: A selective removal of metal and its anion species that are detrimental to subsequent hydrothermal hydrocatalytic conversion from the biomass feed in a continuous or semi-continuous manner prior to carrying out catalytic hydrogenation/hydrogenolysis/hydrodeoxygenation of the biomass that does not reduce the effectiveness of the hydrothermal hydrocatalytic treatment while minimizing the amount of water used in the process is provided.

Abstract: A feeding arrangement for feeding plant material to a treatment vessel is disclosed including a plug screw feeder, a force feeding screw for feeding the plant material to the plug screw feeder in which the force feeding screw is arranged essentially perpendicular to the plug screw, and a feeding device for feeding incoming material to the force feeding screw, and in which the plug screw can rotate at variable speed, and the force feeding screw includes when a distance between the last screw thread of the force feeding screw and the outer diameter of the plug screw is up to 90 mm.

Abstract: Methods for producing ethanol from cellulosic biomass and, in particular, methods for controlling steam explosion pretreatment operations are disclosed. In some particular embodiments, the total solids content of biomass entering a pretreatment digester is calculated to provide operational data and feedback control.

Abstract: A method and system for pulp manufacturing used in connection with a kraft process includes a vertical pressure vessel operated in batch mode, a single-vessel or multi-vessel continuous digester, and other equipment for further processing brown stock, such as for washing, oxygen delignification, bleaching, and drying. A feeder and conveyance system may include a high pressure feeder or direct pump system, and selectively provides fiber-containing material to the continuous digester when making lower grade pulp product and to the vertical pressure vessel when making higher grade pulp such as dissolving pulp. The vertical pressure vessel is used for pre-hydrolysis and neutralization, after which the resulting pulp is fed to the continuous digester for cooking. White liquor and black liquor from the same mill may be used for the neutralization fluids. The same continuous digester is selectively used for cooking in connection with making pulp products of different grades or quality.

Abstract: A biomass processing method including: feeding biomass to an upper reactor inlet; adding liquor to the biomass to create a liquid level below an upper biomass level; treating the biomass; discharging the treated biomass from a bottom reactor outlet; as the biomass flows downward from the biomass upper level to the bottom outlet, moving the biomass between a plurality of pairs of support plates, wherein (i) the pairs of support plates are arranged at different elevations, (ii) the plates of each pair are mounted to sidewalls at a slope with respect to the sidewall that converges the plate inwardly towards an opposite plate along a downward direction, and (iii) each pair of plates converges along a single direction; increasing biomass compaction as the biomass flows between each pair of plates; rapidly releasing compressive forces on the biomass as the biomass flows pass lower edges on each pair of support plates.

Abstract: An apparatus for in-feeding and dewatering biomass that controls the water content of the biomass prior to introduction of the biomass into a process reactor, the in-feeding and dewatering processes being carried out at a pressure higher than or equal to the pressure inside the process reactor thereby providing the advantage of a fluid tight sealing of the process reactor and facilitating its continuous feeding.

Abstract: Paper comprised solely of a nonwood fiber mix is demonstrated to meet the technical physical specifications of commercially produced papers made from wood. The esthetically impressive paper meets nearly every technical specification of commercially produced paper.

Abstract: The present invention relates to a process for the production of microfibrillated cellulose wherein the process comprises the steps of, providing a slurry comprising fibers, adding the slurry to an extruder, treating the slurry in the extruder so that the fibers are defibrillated and microfibrillated cellulose is formed. The invention further relates to a microfibrillated cellulose produced.

Abstract: Continuous transfer of particulate material into pressurized steam reactors is provided by “flow feeder” methods and devices. Material such as lignocellulosic biomass feedstocks are compacted into a “low density” plug, <700 kg/m3, which provides a dynamic seal against pressurized steam through exploitation of a steam condensation zone. The rate at which the steam condensation zone moves into the “low density” plug is offset by the rate at which compacted material is fed into the pressurized reactor. Preferred devices compact material within a flow feeder chamber by use of a loading device that works against counter-pressure provided by an unloading device. Compacted material is actively disintegrated and fed into the reactor by the unloading device. In preferred embodiments, compacted material is fed in a steady-state operation in which the interface between the steam condensation zone and the low pressure inlet zone remains stationary within the flow feeder chamber.

Abstract: The method is for influencing the flow from a strainer construction in a continuous digester. In order to avoid clogging of the withdrawal compartment in the strainer construction, an additive that counteracts precipitation processes is added directly to the withdrawal compartment while the cooking fluid is withdrawn from the withdrawal compartment. The addition of chemicals can take place at the same time as the withdrawn cooking fluid is withdrawn from the digester and the strainer construction, or while the withdrawn cooking fluid is fully or partially re-circulated back to the withdrawal compartment.

Abstract: The invention relates to a method of making a paper or paper board, in which method cut pulp is prepared by cutting basic cellulosic fiber pulp at the consistency of at least 25% so that the average fiber length of the basic pulp is decreased by more than 25% and the SR number of the cut pulp is at most 20% higher than that of the basic pulp, and the cut pulp is used as a raw material in the preparation of a stock.

Abstract: The present invention provides an apparatus and a method for conversion of cellulosic material, such as chopped straw and corn stover, and household waste, to ethanol and other products. The cellulosic material is subjected to continuous hydrothermal pre-treatment without addition of chemicals, and a liquid and a fiber fraction are produced. The fiber fraction is subjected to enzymatic liquefaction and saccharification. The method of the present invention comprises: performing the hydrothermal pre-treatment by subjecting the cellulosic material to at least one soaking operation, and conveying the cellulosic material through at least one pressurized reactor, and subjecting the cellulosic material to at least one pressing operation, creating a fiber fraction and a liquid fraction; selecting the temperature and residence time for the hydrothermal pretreatment, so that the fibrous structure of the feedstock is maintained and at least 80% of the lignin is maintained in the fiber fraction.

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: The method and a device is for the dilution of dewatered cellulose pulp that maintains a consistency of 20-30% or greater. By shredding of the pulp to a finely divided dry-granulate, dilution to a homogeneous consistency in the medium consistency range can take place exclusively through hydrodynamic effects from the addition of dilution fluid. The dilution fluid is added to granulate at a position at which granulate is in free fall in a standpipe and above a level LiqLEV of diluted pulp in the standpipe. A number of nozzles are arranged around the periphery of the stand pipe, directed in towards the centre of the stand pipe, obliquely downwards in the direction of fall of the granulate. It is possible through this simplified procedure to avoid completely the conventional dilution screws, and this reduces the investment costs and operating costs, while at the same time unnecessary mechanical influence of the pulp fibres can be avoided.

Abstract: A chip pretreatment process which comprises conveying the feed material through a compression screw device having an atmosphere of saturated steam at a pressure above about 5 psig, decompressing and discharging the compressed material from the screw device into a decompression region, feeding the decompressed material from the decompression region into a fiberizing device, such as a low intensity disc refiner, where at least about 30 percent of the fiber bundles and fibers are axially separated, without substantial fibrillation of the fibers. In a more specific form the invention is directed to a process for producing mechanical pulp, including the steps of fiberizing wood chip feed material in a low intensity disc refiner until at least about 30 percent of the fibers are axially separated with less than about 5 percent fibrillation, and subsequently refining the fiberized material in a high intensity disc refiner until at least about 90 percent of the fibers are fibrillated.

Abstract: A chip pretreatment process which comprises conveying the feed material through a compression screw device having an atmosphere of saturated steam at a pressure above about 5 psig, decompressing and discharging the compressed material from the screw device into a decompression region, feeding the decompressed material from the decompression region into a fiberizing device, such as a low intensity disc refiner, where at least about 30 percent of the fiber bundles and fibers are axially separated, without substantial fibrillation of the fibers. In a more specific form the invention is directed to a process for producing mechanical pulp, including the steps of fiberizing wood chip feed material in a low intensity disc refiner until at least about 30 percent of the fibers are axially separated with less than about 5 percent fibrillation, and subsequently refining the fiberized material in a high intensity disc refiner until at least about 90 percent of the fibers are fibrillated.

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 vessel is constructed with (preferably substantially stationary) screen surfaces which minimize compaction of comminuted cellulosic fibrous material, and allow springback of the material, as it flows downwardly. A slurry of wood chips, sawdust, or pulp is passed downwardly past one or more screen surfaces, which have a number of parts, including at least a first perforated part through which liquid is extracted, and a substantially solid part substantially immediately adjacent and below the first part which has a step out to relieve compaction and allow springback of the material.

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: The method is for pre-treatment of chips that are fed to a sulphate cooking process. Through acidification of the chips in an acidic treatment fluid with a subsequent draining of free treatment fluid before subsequent steaming or wet-steaming, a high concentration of free hydrogen ions is established within the chip pieces. When the chips are subsequently formed into slurry with preferably a sulphide-rich alkali cooking fluid, H2S is formed locally in the chip pieces which gives a yield-increasing effect in the subsequent cooking step of 1-3%.

Abstract: Wood chips having low bleachability are impregnated with a chemical liquor at a pH range of 7-12 in aqueous solution and the chemical liquor from the impregnated chips is drained, whereby extractives contained in the chips and consuming bleaching agents can be removed to improve the effect of bleaching agents in a subsequent bleaching step. Bleached mechanical pulp is prepared by defibration by primary refining—bleaching—beating by secondary refining wherein pulp fibers are washed after defibrating wood chips having low bleachability and before bleaching the pulp fibers, whereby the amount of bleaching agents used can be reduced and bleached mechanical pulp having a Hunter brightness of 45-65% after secondary refining can be obtained.

Abstract: In a process of treating wood chips for reduction of the concentration of undesirable inorganic elements prior to cooking in a production line for chemical pulp, the wood chips, having entrapped air, are treated with an aqueous leaching liquor at elevated temperature and pressure, followed by draining at atmospheric pressure or below atmospheric pressure, the pressures being controlled to yield a moisture content in the wood chips as low as possible for adequate leaching result and behavior of the chips in a subsequent digester. The aqueous leaching liquor is e.g. pulp mill process water with a low content of undesirable inorganic components, such as bleach plant spent liquor or condensate. The aqueous leaching liquor drained from the treated wood chips may be purified and recycled back to the process.

Abstract: A system and method for thermomechanical refining of wood chips comprises preparing the chips for refining by exposing the chips to an environment of steam to soften the chips, compressively destructuring and dewatering the softened chips to a solids consistency above 55 percent, and diluting the destructured and dewatered chips to a consistency in the range of about 30 to 55 percent. The destructuring partially defibrates the material. This diluted material is fed to a rotating disc primary refiner wherein each of the opposed discs has an inner ring pattern of bars and grooves and an outer ring pattern of bars and grooves. The destructured and partially defibrated chips are substantially completely defibrated in the inner ring and the resulting fibers are fibrillated in the outer ring.

Abstract: The method is for distributing cellulose pulp that has a 2-12% consistency. A manifoid housing is in fluid communication with distributor housing. The distributor housing has holes that are distributed along a generatrix of the distribution housing. The cellulose pulp is fed into an inlet of the manifold housing. The feed screw is rotated to convey the cellulose pulp in the transverse direction through the distributor housing. The feed screw sweeps across the holes in the distributor housing to urge the cellulose pulp through the holes. The cellulose pulp is uniformly fed through the holes and then through an inlet to dewatering drums. The cellulose pulp is run between the dewatering drums and a trough to form a pulp web. The pulp web is dewatered in a press nip formed between the dewatering drums. The dewatered pulp web is collected by a feed screw.

Abstract: The invention relates to a feed arrangement for feeding chips to chip bins (1) in the production of cellulose pulp in continuous digesters (16), in which the chip bin is constituted by a treatment vessel having a top and a bottom, in which the chips are fed into the top (13) of the treatment vessel and fed out via the bottom of the treatment vessel using suitable lock members (10, 11). Distribution devices (4a, 4b) for the addition of steam are disposed in the treatment vessel so as to heat the chips to a level above 80° C., preferably around 100° C., when the chips are fed out via the bottom of the treatment vessel. By virtue of the fact that the chips are fed into the treatment vessel via at least one liquid lock (30) and the treatment vessel is otherwise sealed off, the quantity of driven-off gases from the chip bin is reduced to a minimum, at the same time as an effective utilization of available energy is obtained.

Abstract: A vessel is constructed with (preferably substantially stationary) screen surfaces which minimize compaction of comminuted cellulosic fibrous material, and allow springback of the material, as it flows downwardly. A slurry of wood chips, sawdust, or pulp is passed downwardly past one or more screen surfaces, which have a number of parts, including at least a first perforated part through which liquid is extracted, and a substantially solid part substantially immediately adjacent and below the first part which has a step out to relieve compaction and allow springback of the material.

Abstract: A process for producing microcrystalline cellulose. The process comprising the following steps: a) preparation of a pulp by repulping, b) pressing of the pulp obtained in a), c) decompaction of the pulp obtained in b), d) feeding of the pulp obtained in c) into a pre-heated reactor, e) cooking of the pulp at a temperature, a time and a pressure allowing to obtain a pulp having a desired degree of polymerization, f) cooling and partial controlled depressurization of the reactor by purging the reactor, followed by a water injection into the jacket and directly into the reactor, g) filtering the pulp obtained in f), h) bleaching of the pulp obtained in g), and i) drying the pulp obtained in h). The process allows the application of a controlled depressurization in step f), which in turn allows to keep the natural texture of the fibers and to obtain a cellulose having a low degree of polymerization.

Abstract: Process and container for stacking and diluting paper fiber stock. The process includes stacking a high-consistency stock in a first volume for defined dwell time, conveying stock to second volume arranged to adjoin downstream first volume, diluting stock in second volume at least to a pumpable consistency, and drawing off diluted stock as suspension through a wire. Process includes generating circulation flow in second volume, such that circulation flow facilitates conveying of stock located on boundary of first volume into second volume, diluting stock, and drawing stock through wire. Process includes rotating rotor to keep wire clear, and generating, with screw coil arranged directly in front of rotor, flow that runs in axial direction of screw coil and guides diluted suspension away from wire. The instant abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

Abstract: A method for washing a fibre suspension with washing liquid, in which, in accordance with the invention, the fibre suspension is introduced into an annular treatment channel (24) that has an inlet end (72) and an outlet end (73) and is concentric with an axis of rotation (5) to form an inner annular layer (74), washing liquid simultaneously being introduced into the treatment channel form an outer layer (75), which surrounds the inner annular layer. The fibre suspension and washing liquid are caused to rotate in the treatment channel whilst moving from said inlet end to said outlet end, fibres in the fibre suspension being caused to move into the outer layer of washing liquid, under the influence of the centripetal force, so that an accept (29), the liquid phase of which completely or mostly consists of washing liquid, is discharged at the outlet end of the treatment channel.

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 a single vane slurry pump in series with a centrifugal slurry pump both of which are 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.

Abstract: The invention includes a treatment apparatus for treating fibrous cellulosic raw material suitable for use in a paper making plant comprising extracting means for extracting contrary material from the raw material, crushing means for crushing the raw material to remove nodes therefrom and splitting means for splitting the crushed raw material lengthways. A co-rotating twin screw conveyor is used to pulp the crushed material, the conveyor being divided up into a plurality of zones, means for inserting treatment materials into a least one zone and means for controlling the temperature and/or pressure of all of the zones. The black liquor effluent produced in the pulping process is treated in an apparatus comprising an evaporator for concentrating the liquor to 30-70% solids, a processing vessel for treating the concentrated liquor at a temperature of between 300-600° C., and a closed conveyor for transporting the concentrated liquor from the evaporator to the processing vessel in excess of 90° C.

Abstract: A pulp product that has a low COD is comprised of an unbleached pulp that is soaked and washed in alkaline water for a sufficient time so that the COD after soaking and washing is less than or equal to 2.0 kg/1000 kg of dry pulp. The pulp is produced by repetitively soaking and washing an unbleached pulp in alkaline water that is never allowed to drop below pH 7.0. The pulp is soaked and washed for a total of at least 220 minutes at an elevated temperature to produce the pulp product that has a low COD.

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 a single vane slurry pump in series with a centrifugal slurry pump both of which are 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.

Abstract: A pulper in a stock preparation system includes a housing with a fiber inlet, at least one water inlet, at least one outlet and an inner chamber. A plurality of rotatable augers extend into the inner chamber.

Abstract: A pulper in a stock preparation system includes a housing with a fiber inlet, at least one water inlet, at least one outlet and an inner chamber. A plurality of rotatable augers extend into the inner chamber.

Abstract: In a cellulose pulp handling vessel having a first diameter material storing or treating portion above a second diameter discharge which is at least 20% less than the first diameter, reduced compression of the material and reduced power requirements of an agitator (if used), compared to prior art constructions are provided. A first transition, preferably a substantially smooth interior surface substantially frusto-conical transition, is provided between the first and second diameters. A second single-convergent transition may be provided above the first transition. A rotating agitator with at least two arms and associated paddles may be mounted for rotation in the transition about a substantially vertical axis for agitating the material in the transition. If desired, the transition may be moved, such as with a vibrator or oscillator. The invention is particularly suitable for pulp digesters and impregnation vessels.

Abstract: A feed system for a cellulose pulp treating vessel (such as a continuous digester) is not limited by the required L/W ratio of the pump feeding a wood chip slurry to a high pressure transfer device, the feed system may be kept at a low temperature to minimize flashing of liquid into steam, and a return conduit from the treatment vessel to the transfer device high pressure inlet may be eliminated. Some of the liquid is removed from the slurry just before the low pressure inlet to the transfer device, and/or just after the high pressure outlet, to reduce the L/W ratio of the slurry by at least 0.25, e.g. from 3.0:1 to 2.25:1 just before the low pressure inlet, and from, 7.0:1 to 5.0:1 substantially immediately after the high pressure outlet.

Abstract: A feed system for a cellulose pulp treating vessel (such as a continuous digester) is not limited by the required L/W ratio of the pump feeding a wood chip slurry to a high pressure transfer device, the feed system may be kept at a low temperature to minimize flashing of liquid into steam, and a return conduit from the treatment vessel to the transfer device high pressure inlet may be eliminated. Some of the liquid is removed from the slurry just before the low pressure inlet to the transfer device, and/or just after the high pressure outlet, to reduce the L/W ratio of the slurry by at least 0.25, e.g. from 3.0:1 to 2.25:1 just before the low pressure inlet, and from 7.0:1 to 5.0:1 substantially immediately after the high pressure outlet.

Abstract: In a cellulose pulp handling vessel having a first diameter material storing or treating portion above a second diameter discharge which is at least 20% less than the first diameter, reduced compression of the material and reduced power requirements of an agitator (if used), compared to prior art constructions are provided. A first transition, preferably a substantially smooth interior surface substantially frusto-conical transition, is provided between the first and second diameters. A second single-convergent transition may be provided above the first transition. A rotating agitator with at least two arms and associated paddles may be mounted for rotation in the transition about a substantially vertical axis for agitating the material in the transition. If desired, the transition may be moved, such as with a vibrator or oscillator. The invention is particularly suitable for pulp digesters and impregnation vessels.

Abstract: A method of treating wood-fiber pump, particularly wood-fiber pulp that contains recycled paper, comprises delivering the pulp to and advancing the pulp in a heating zone while delivering steam to the heating zone. The pulp is finely-divided in a disperser and the finely-divided pulp delivered to a screw press without separate departure of steam, so as to compact the pulp in the end of the screw press and therewith form a plug seal. At the same time, one or more bleaching chemicals is or are supplied during one or more treatment stages, and the temperature of the pulp is regulated to obtain an optimal bleaching process or optimal bleaching processes. The temperature of the pulp can be raised or lowered by supplying steam or water thereto respectively. The invention also relates to a plant for carrying out the method.

Abstract: A multi-function process is described for the separation of cellulose fibers from the other constituents of lignocellulosic biomass such as found in trees, grasses, agricultural waste, and waste paper with application in the preparation of feedstocks for use in the manufacture of paper, plastics, ethanol, and other chemicals. This process minimizes waste disposal problems since it uses only steam, water, and oxygen at elevated temperature in the range of 180° C. to 240° C. for 1 to 10 minutes plus a small amount of chemical reagents to maintain pH in the range 8 to 13. An energy recuperation function is important to the economic viability of the process.

Abstract: The invention relates to a process for the treatment of solids with pressurized liquid gases, in particular liquid ammonia, with which the to be treated solid is fed into a pressure reactor at atmospheric pressure. Subsequently the pressurized liquid gas is fed to the pressure reactor and after a pre-set dwell time the resultant liquid gas/solid mixture is expanded explosion-like into an expansion tank. With this at least two reactors are operated in a time-staggered manner. Furthermore an apparatus is described for the treatment of solids with pressurized liquid gases, which comprises at least two parallel arranged pressure reactors for the alternating taking in of a solid and a liquid gas, which each have inlet and outlet openings for the solid provided with shut-off elements as well as each at least one inlet opening for the liquid gas, at least one expansion tank which is connected to the respective pressure reactors, and conveying means for feeding the solid as well as the liquid gas.

Abstract: A method of making fiber bundles and fibrous structures. The efficacy of a fiber bundle in handling complex fluids may be improved by subjecting an aqueous suspension of fibers at high consistency to elevated energy input with sufficient working of the fibers. The fibrous structures prepared according to the methods herein include at least one fiber bundle and at least one debonding agent. The fiber bundle includes at least one particulate material consisting essentially of entangled fibers.

Abstract: A process for production of chemical fibrous pulp for making paper, paperboard and other fibrous products from herbaceous plants, such as kenaf. Pulp from the herbaceous plant is made by a process which involves densification of pieces of all or part of the plants; i.e., both the core and the stalk or just the core portion, into cubes or pellets having a density ranging from about 15 to about 70 lbs/ft3, preferably from about 25 to about 50 lbs/ft3, which are then chemically digested to produce a fibrous pulp. The densified cubes or pellets may be digested alone or together with conventional wood chips. A principal advantage of the invention is that the densified cubes or pellets exhibit significantly better yield and strength after treatment by conventional chemical pulping methods as compared with the undensified material, enabling more efficient and economical use of this material to supplement limited supplies of conventional hardwood and softwood pulp sources.

Abstract: A new and improved way of continuously cooking fiber material, wherein temperatures and alkaline levels are controlled to be maintained within specific levels in different zones of the digesting process in order to optimize chemical consumption and heat-economy and at the same time achieve very good pulp properties. The digesting process includes a top separator that separates the transport liquid from the fiber material and permits the fiber material to be exposed to the cooking liquid.