Abstract: A composition comprising lignin compounds possessing 8-30 (or 5-15 or 8-12) phenyl rings interconnected by ether and alkylene linkages and containing hydroxy and/or methoxy groups attached to said phenyl rings, wherein said composition possesses a glass transition temperature of 80-100° C. (or 95-98° C.) and a degree of substitution (DS) of carboxylic acid groups per phenyl ring of at least 0.5 and a DS of methoxy groups per phenyl ring of no more than 1.2, 1.1, or 1.0, wherein at least 90 wt % of said lignin compounds has a molecular weight within a range of 500-5000 g/mol, 1500-3000 g/mol, or 2000-2500 g/mol and/or wherein the molecular weight distribution of the lignin compounds is characterized by a polydispersity index of 1.0-1.5, 1.0-1.4, or 1.0-1.3, and wherein other lignin compounds not possessing the above characteristics are not present. Methods for producing the lignin extract and lignin copolymers and blends produced therefrom are also described.

Abstract: A method for producing a high yield Kraft pulp is provided. In particular, the method involves adding a composition comprising an organic amine phosphonate and a sulphonated linear alcohol ethoxylate surfactant to a pulping process. The composition enhances the delignification of cellulosic fiber in chemical wood pulps.

Abstract: A saccharification reaction mixture, a saccharification enzyme composition, and a saccharide production method are aimed to enhance saccharization rate by use of an enzyme in a simple step as well as a method for producing ethanol from a saccharide. The saccharification reaction mixture can saccharify at least one of cellulose and hemicellulose and contains at least one of cellulose and hemicellulose, a saccharification enzyme, silica or a silica-containing substance, and at least one compound (A) selected from the group made of thiourea, a thiourea derivative, an isothiourea derivative, and a salt of any of these.

Abstract: A method for obtaining a strong hydrolysate from cellulosic material after a hydrolysis in a batch digester is disclosed. According to the invention the cellulosic material is exposed to a 2 stage hydrolysis with a first steam phase hydrolysis followed by a liquid phase hydrolysis, and wherein the steam phase is conducted such that the degree of packing of the cellulosic material results in at least a 20% up to 100% packing increase. The liquid phase hydrolysis includes adding hot and preferably acidified hydrolysis liquid and not establishing a total L/W ratio above 3.5, but sufficient to keep the cellulosic material under the level of the hydrolysis liquid.

Abstract: The present invention provides an improved catalytic fast pyrolysis process for increased yield of useful and desirable products. In particular, the process comprises an improved catalytic fast pyrolysis process for producing aromatic compounds, such as, for example, benzene, toluene and xylenes, from biomass feedstock containing impurities, such as, for example alkali and alkaline earth metal, sulfur and nitrogen components.

Abstract: The invention relates to a process for producing a dissolving pulp from a cellulosic starting material using the kraft process, comprising the step of cooking the starting material with a cooking liquor. The process according to the invention characterized in that the starting material is exposed to a steam treatment prior to cooking and that the pulp obtained by cooking is subjected to cold caustic extraction (CCE) in the course of further processing.

Abstract: An analytical method and container for measuring the soap content in black liquor. The method includes: a first step where a defined amount of black liquor is arranged in the container, a second step where the black liquor is centrifuged and a soap concentrate is gathered in the upper part of the container, a third step where the amount of soap concentrate is determined, and a fourth step where the soap content is calculated. By centrifuging the black liquor soap concentrated with a soap content of 58-62% is obtained, which enables measurement of the dry matter with an accuracy of ±2% within a very short time period. The container includes a neck with scale marks and a lower part. In one embodiment, the analytical method includes a fifth step where a modification of the calculated soap content is made with consideration to the density of the black liquor.

Abstract: A wet process for cleaning biomass is disclosed, comprising: introducing biomass feedstock to a vibrating separator, to generate an overflow stream and an underflow stream, wherein the overflow stream comprises biomass and large grit, and wherein the underflow stream comprises fines and small grit; introducing the overflow stream to a kinetic separator, to generate an intermediate biomass stream and a large-grit stream; introducing the underflow stream and elutriation water to a hydroclone separator, to generate a wet biomass-fines stream and a small-grit stream; separating water contained in the wet biomass-fines stream and recycling it as elutriation water, to generate a biomass fines stream; and combining the biomass fines stream with the intermediate biomass stream, thereby generating clean biomass. An alternative embodiment for a dry process to clean biomass is also disclosed. The clean biomass may be used in a wide variety of biorefining processes.

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 method for the isolation of lignin from a lignocellulosic biomass, comprising providing a lignocellulosic biomass; extracting sugar free lignin from the lignocellulosic biomass by contacting said biomass with an organic aqueous solution comprising water and at least one water miscible organic solvent, either discontinuously or continuously, whereby a biomass-solvent suspension is formed; separating the sugar free lignin solution from the biomass-solvent suspension to obtain a sugar free lignin solution and a cellulosic material enriched with lignin carbohydrate complexes and hemicellulose, and optionally isolating sugar free lignin from the sugar free lignin solution; extracting the lignin carbohydrate complexes from the cellulosic material enriched with lignin carbohydrate complexes and hemicellulose by contacting said cellulosic material with a liquid comprising at least water, whereby treated biomass suspension is formed; separating the lignin carbohydrate complexes solution from said treated biomass sus

Abstract: An animal feed producing system comprises a compression screw assembly. The compression screw assembly includes at least a first screw, a second screw and a plurality of barrels. The first and second screws include a plurality of flights and roots. The plurality of screws is configured such that they include a plurality of sections. Each section comprises a set of plurality of flights and a plurality of roots configured to perform a specific compression function, such as perpendicular compression and lateral compression.

Abstract: Digestion of cellulosic biomass to produce a hydrolysate may be accompanied by the formation of cellulosic fines which may be damaging to system components. Biomass conversion systems that may address the issue of cellulosic fines may comprise a fluid circulation loop comprising: a hydrothermal digestion unit; a solids separation unit that is in fluid communication with an outlet of the hydrothermal digestion unit; where the solids separation unit comprises a plurality of filters and the filters are in fluid communication with the fluid circulation loop in both a forward and a reverse flow direction; and a catalytic reduction reactor unit that is in fluid communication with an outlet of the solids separation unit and an inlet of the hydrothermal digestion unit; where at least one of the plurality of filters is in fluid communication with an inlet of the catalytic reduction reactor unit.

Abstract: Soak vessels for impregnating biomass with a liquid such as a dilute acid and methods for impregnating biomass are disclosed. In some embodiments, the soak vessel includes an impeller assembly with impellers that create a vortex to submerge the biomass, that agitate and separate contaminants from the biomass and that direct biomass and contaminants to separate vessel outlets.

Abstract: This specification discloses an improved method for conducting the removal of C5 xylan based sugars from biomass. The improved method involves a series of soakings and washings of the biomass as opposed to conducting one soaking and washing step.

Abstract: A reaction vessel including: a material input receiving cellulosic material and a material discharge for the cellulosic material, wherein the cellulosic material flows through the reaction vessel from the material input to the material discharge; a hydrolysate and liquid extraction screen; a hydrolysis zone between the material input and the hydrolysate and liquid extraction screen; a wash zone between the hydrolysate and liquid extraction screen and a wash liquid extraction screen; a wash liquid inlet port for introducing a wash liquid into the wash zone, wherein at least a portion of the wash liquid entering the wash liquid inlet port flows through the wash zone and is extracted by the hydrolysate and liquid extraction screen; a cooking zone between the wash zone and the material discharge and a cooking liquor extraction screen at or below the cooking zone and above the material discharge.

Abstract: A biomass hydrothermal decomposition apparatus includes, a biomass feeder (31) that feeds biomass material (11) under normal pressure to under increased pressure, a hydrothermal decomposition device (41A) that allows the fed biomass material (11) to be gradually moved inside a gradient device main body (42) from a lower end thereof with a conveyor screw (43), and also allows hot compressed water (15) to be fed from an other end of a feed section (31) for the biomass material into the main body (42), so as to cause the biomass material (11) and the hot compressed water (15) to countercurrently contact with each other and undergo hydrothermal decomposition, and that transfers a lignin component and a hemicellulose component into the hot compressed water, so as to separate the lignin component and the hemicellulose component from the biomass material (11); and a biomass discharger (51) that discharges, from the upper end of the device main body (42), a biomass solid residue (17) under increased pressure to an un

Abstract: A reactor vessel system including: a first reactor vessel having a hydrolysate and liquid extraction screen, a first region above the extraction screen that is maintained at conditions promoting a hydrolysis reaction in the cellulosic material, a second region below the extraction screen in which the hydrolysis is substantially suppressed and a wash liquid inlet below the extraction screen providing wash liquid at a temperature below a hydrolysis temperature; a transport pipe having an inlet coupled to the first reactor vessel and an outlet coupled to a second reactor vessel, and the second reactor vessel includes a liquid discharge that extracts a portion of liquid from the second reactor vessel and directs the portion of liquid to the first reactor vessel or to the transport pipe.

Abstract: When processing cellulosic biomass, it may be desirable for a digestion unit to operate without being fully depressurized for process efficiency purposes. A biomass conversion system can comprise a first digestion unit and a second digestion unit that are operatively connected to one another; a valve separating the first digestion unit from the second digestion unit; a fluid circulation loop establishing fluid communication between an outlet of the first digestion unit and an inlet of the second digestion unit; and a bypass line establishing fluid communication between an outlet of the second digestion unit and the fluid circulation loop.

Abstract: A method for treating a cellulosic material comprising extracting the cellulosic material with an extractant to selectively extract hemicellulose therein and separating the extracted hemicellulose to form a cellulosic product comprising less hemicellulose than the cellulosic material. The extractant comprises an amine oxide and a non-solvent. The cellulosic product retains the cellulosic fiber morphology.

Abstract: The present invention relates to [1] a process for producing a lignin degradation product, including the following steps (1) to (3), and [2] a lignin degradation product produced by the process as described in the above [1]: Step (1): subjecting a lignocellulose raw material to enzymatic saccharification treatment to obtain a saccharification residue; Step (2): subjecting the saccharification residue obtained in the step (1) to heat treatment in a mixed solvent containing water and an organic solvent having a solubility in 20° C. water of not less than 90 g/L to obtain a heat treatment solution containing the lignin degradation product; and Step (3): subjecting the heat treatment solution obtained in the step (2) to solid-liquid separation to remove insoluble components from the heat treatment solution, thereby obtaining the lignin degradation product.

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 prehydrolysis of wood chips or other lignocellulosic material in a vessel having a gaseous portion and a liquid portion. The vessel includes at least one stress relieving piece that inhibits overcompression of the lignocellulosic material. The vessel operates in a continuous process. A slurry of lignocellulosic material and liquid is removed from the bottom of the vessel.

Abstract: The method is for the preparation of kraft pulp with increased pulping yield from lignin-containing cellulosic material using polysulfide cooking liquor. In order to increase carbohydrate stabilization and hence the yield from a kraft cooking process a first impregnation stage is using polysulfide cooking liquor implemented at high alkali and polysulfide concentration and at a low temperature.

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: A reactor vessel system including: a first reactor vessel having a hydrolysate and liquid extraction screen, a first region above the extraction screen that is maintained at conditions promoting a hydrolysis reaction in the cellulosic material, a second region below the extraction screen in which the hydrolysis is substantially suppressed and a wash liquid inlet below the extraction screen providing wash liquid at a temperature below a hydrolysis temperature; a transport pipe having an inlet coupled to the first reactor vessel and an outlet coupled to a second reactor vessel, and the second reactor vessel includes a liquid discharge that extracts a portion of liquid from the second reactor vessel and directs the portion of liquid to the first reactor vessel or to the transport pipe.

Abstract: The method is for the production of cellulose pulp in a continuous digester system. Chips are impregnated in an impregnation vessel. The chips are then fed to a subsequent digester vessel in a transfer fluid. A black liquor withdrawal is taken from the digester, which withdrawal is led to the bottom to heat the chips before the chips are fed out from the impregnation vessel. A transfer fluid is withdrawn from the digester and led to the impregnation vessel to act as an impregnation fluid. At least a portion of the transfer fluid that was withdrawn from the top of the digester passes an indirect heat exchanger, in which the transfer fluid withdrawn from the top of the digester at a temperature of at least 125° C. exchanges heat indirectly with a first fluid for the production of steam from the first fluid.

Abstract: Methods and systems for fractionating lignocellulosic biomass including hemicellulose, cellulose and lignin, including exploding the biomass cells to devolatilize the biomass, hydrolyzing the hemicellulose to produce a liquid component including hemicellulosic sugars and a solid component including less than 10% hemicellulose, separating the liquid and solid components, vaporizing the cellulose in the solid component, and condensing the cellulosic sugar vapors. The methods and systems may vaporize the cellulose in a continuous steam reactor at a temperature of about 400-550° C. and a pressure of about 1-3 bara. Electromagnetic and/or electroaccoustic treatment such as ultrasound and/or microwave treatment may be applied to the biomass immediately before or during cellulose hydrolysis.

Abstract: The method, system and a withdrawal screen section are for the impregnation of chips during the manufacture of chemical pulp. Chips are both steamed and impregnated in a low pressure impregnation vessel, using pressurized hot spent cooking liquor BL as the main part of the impregnation liquid. The hot spent cooking liquor produces most of the steam BLST necessary for steaming the chips. At least two independent first and second screen rows, SC1 and SC1b respectively, are installed in order to improve the process in the impregnation vessel. The first screen row withdraws acidified treatment liquor for disposal which otherwise would be a parasitic acidified waste fluid in the system. The second screen row recirculates treatment fluid back to center of treatment vessel in order to even out the pH profile over the cross section of the vessel.

Abstract: The invention relates to methods of manufacturing nano pulp, wherein cellulose containing raw material is accelerated in a continuous gas and/or liquid flow, whereby the material is disintegrated and nano pulp is produced. The gas and/or liquid flow may be created by reduction of an elevated pressure in a reactor holding the cellulose containing raw material. The invention also relates to the nano pulp produced.

Abstract: Provided is a process for manufacturing shaped cellulose materials from lignocellulose where a dissolving grade pulp is manufactured and dissolved in an aqueous alkaline or acidic solvent system forming a solution suitable for shaping new cellulose structures including fibers, films and cellulose derivatives. At least a part of the spent cellulose dissolving or cellulose shaping chemicals are recovered in one or more unit operations in a pulp mill chemical recovery cycle.

Abstract: The invention relates to a process for producing a dissolving pulp from a cellulosic starting material using the kraft process, comprising the step of cooking the starting material with a cooking liquor. The process according to the invention characterized in that the starting material is exposed to a steam treatment prior to cooking and that the pulp obtained by cooking is subjected to cold caustic extraction (CCE) in the course of further processing.

Abstract: A method for the production of alcohol and other bioproducts from power boiler woody biomass extract containing hemicelluloses, with or without combining extract from wood prior to Kraft cooking. The process is integrated with the host Kraft pulp mill plant process to minimize the heat loss from extracting hemicelluloses and the energy used in the process.

Abstract: A method including: pretreating biomass feed stock in a first pressurized reactor, wherein the feed stock undergoes hydrolysis in the first pressurized reactor; discharging the feed stock from the first pressurized reactor to a pressurized sealing device having a first pressurized coupling to a feedstock discharge port of the first pressurized reactor; maintaining a vapor phase in the first pressurized reactor by injecting steam; washing the feed stock; draining dissolved hemi-cellulosic material extracted from the feed stock; discharging the feed stock from the pressurized sealing device through a second pressurized coupling to a second pressurized reactor; in the second pressurized reactor, infusing cells of the feed stock with steam or water vapor, and rapidly releasing the pressure applied to the feed stock to cause steam expansion in the cells of the feed stock and refine the feed stock.

Abstract: The invention relates to a process for producing a dissolving pulp from a cellulosic starting material using the kraft process, comprising the step of cooking the starting material with a cooking liquor. The process according to the invention characterized in that the starting material is exposed to a steam treatment prior to cooking and that the pulp obtained by cooking is subjected to cold caustic extraction (CCE) in the course of further processing.

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: 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 process for the pretreatment of lignocellulosic biomass, in particular during the production of ethanol from biomass. The process including a cooking step where the biomass is exposed to steam at elevated temperatures and pressures for a preselected period of time in a treatment vessel. During the process, volatile and liquid compounds are purged from the treatment vessel.

Abstract: A method of producing a modified pulp for use in paper or paper web products, the method comprising treating wood chips in an extraction process to remove hemicellose to form treated wood chips; and subjecting said treated wood chips to chemical or semichemical pulping to form a modified Kraft pulp wherein the amount of hemicellulose contained in the modified Kraft pulp is from about 5 to about 10% by dry weight of the modified pulp.

Abstract: An omnibus process of pulping and bleaching lignocellulosic materials in which a charge of a lignocellulosic material is biopulped and/or water extracted prior to pulping and bleaching. The lignocellulosic material may be mechanically pulped and bleached in the presence of an enzyme that breaks lignin-carbohydrate complexes. The aqueous extract in embodiments including a water extract step is separated into acetic acid and hemicellulose sugar aqueous solutions.

Abstract: The method increases the yield and improves the beatability of kraft pulp. During the progression of the cooking process, more than one cooking liquor with a dissolved content of hemicellulose is drawn off and then reintroduced to the last phases of the cooking process, to re-precipitate the hemicellulose on the fibers. The hemicellulose rich cooking liquors are adjusted so that they, upon being added to the last phase of the cooking process are optimized. Early dissolved hemicellulose has a longer chain length than the hemicellulose that dissolves in the cooking liquor in the later phases of the cooking process, and they also have different tendencies to precipitate on the wood chips softened in the cooking process.

Abstract: A prehydrolysis of wood chips or other lignocellulosic material in a vessel having a gaseous portion and a liquid portion. The vessel includes at least one stress relieving piece that inhibits overcompression of the lignocellulosic material. The vessel operates in a continuous process. A slurry of lignocellulosic material and liquid is removed from the bottom of the vessel.

Abstract: An improved method for treating lignocellulosic material, including a prehydrolysis-mass transfer process, which produces a concentrated hydrolysate volume during the time required for the hydrolysis itself. The improved process comprises the heating of the digester and chip content by direct steam to the required hydrolysis temperature, starting a flow of hot, stored hydrolysate to the top of the chip bed in order to create a trickle-bed type down-flow of hydrolysate, collecting a first fraction of the trickled-down hydrolysate as a product fraction, adding extraction liquid and continuing the trickle flow to collect a second hydrolysate fraction, which will be discharged from the digester to a hot hydrolysate storage tank to be used as the first trickle flow liquid in the next batch.

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: In a cooking process of a lignocellulose material, pulp yield can be improved at the same Kappa number and an effective alkali addition rate can be reduced at the same Kappa number.

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: Disclosed is a method for increasing the concentration of xylose in lignocellulosic hydrolysate. The method includes the step of extruding lignocellulosic material and mixing the lignocellulosic material with diluted acid and the step of conducting hot-water extraction on the mixture. Hence, the concentration of the xylose in the lignocellulosic hydrolysate can achieve a high concentration of 60 g/L, and the yield of the xylose can reach to 90%.

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 system and method for digesting cellulosic material to extract fermentable sugars, lignin, and pulp is disclosed. One embodiment comprises a continuous digester comprising a cellulosic material feed section including a pre-steam and impregnation zone, a sugar extraction zone, a lignin extraction zone and a cooking zone, the continuous digester to impregnate the cellulosic material with a mild acid solution and continuously digest the cellulosic material to extract fermentable sugars, lignin, and pulp.

Abstract: Improvements in a process for rapid acid hydrolysis of lignocellulosic material and in a hydrolysis reactor, said lignocellulosic material being fed in different levels of a reactor and contacted with flows of lignin organic solvent, water and an extremely dilute solution of a strong inorganic acid, for obtaining a liquid phase of hydrolysis extract and a solid phase of non-reacted and non-dissolved material. A controlled steam flow is injected into the different levels of the reactor, so as to provide adequate temperatures of organic solvent and strong inorganic acid and forming the desired products (sugars). A flow of the liquid phase is recirculated in different levels of the reactor, the remainder thereof being withdrawn from the reactor, abruptly cooled with the solvent submitted to evaporation to obtain a concentrate. The lignin is transferred by decantation and the concentrate is transferred to subsequent process steps.