METHOD AND APPARATUS FOR BIOMASS FRACTIONATION

Description

DESCRIPTION OF GOVERNMENT-SPONSORED RESEARCH & DEVELOPMENT

This study was conducted at the Korea Institute of Science and Technology (KIST) under the management of the National Research Foundation of Korea under the Ministry of Science and ICT, and the research project name is KIST Research Operating Cost Support (Main Project Cost), and the research project name is Development of Source Technology for Electro Super Cellulose Composite Material (Unique Project Number: 2710034017, Project Number: 2E33200).

CROSS REFERENCE TO RELATED APPLICATION

The present application claims priority to Korean Patent Application No. 10-2024-0186100, filed Dec. 13, 2024, the entire contents of which are hereby incorporated by this reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present disclosure discloses a method and apparatus for biomass fractionation.

Description of the Related Art

In order to respond to climate change and maintain civilization, it is necessary to use biomass, particularly lignocellulose containing lignin, as a carbon-neutral carbon source that may replace petroleum and avoid conflict with food.

Lignocellulose is mainly composed of cellulose, hemicellulose, and lignin. Cellulose is a linear polymer having glucose as a monomer, and hemicellulose is a heterogeneous branched polymer of pentose and hexose. Lignin is amorphous and is a highly branched polymer of phenylpropane units, accounting for about 35 wt % of biomass (on a dry basis). However, in most bioethanol production plants and pulp and paper mills, the focus is only on using cellulose and hemicellulose portions, which are easy to convert. Until now, in case of biorefineries using lignocellulose, the industry has been created based on corn or plant/animal oils, and biorefineries using lignocellulose have not been practically industrialized due to economic feasibility.

Conventionally, in order to achieve the high added value of lignin, attempts have been made to produce sustainable aviation fuel, phenolic compounds, and the like through subsequent depolymerization and deoxygenation, etc. after fractionating lignin while maintaining its reactivity (aryl-ether interlink). However, due to difficulties in continuously supplying solid raw materials to a reactor under relatively high-temperature, high-pressure, and corrosive conditions, only a batch process has been proposed.

SUMMARY OF THE INVENTION

In one aspect, the present disclosure is directed to providing a biomass fractionation apparatus capable of continuous operation.

In another aspect, the present disclosure is directed to providing a biomass fractionation method capable of producing reactive lignin using the biomass fractionation apparatus.

In one aspect, the present disclosure is directed to providing a biomass fractionation apparatus, including: a biomass supply unit; a biomass mixing unit formed below the biomass supply unit, into which biomass supplied from the biomass supply unit is introduced; a solvent supply unit formed separately from the biomass supply unit and configured to supply a solvent to the biomass mixing unit; a biomass fractionation unit formed below the biomass mixing unit, to which biomass mixed with the solvent in the biomass mixing unit is transferred, and in which cellulose, hemicellulose, and lignin are fractionated; a solid collection unit formed below the biomass fractionation unit and configured to collect a solid fraction introduced from the biomass fractionation unit; and a liquid collection unit formed in connection with the solid collection unit and configured to collect a liquid fraction introduced from the biomass fractionation unit, in which the biomass is supplied to the biomass mixing unit at atmospheric pressure, and is then transferred from the biomass mixing unit to the biomass fractionation unit in a free-fall manner, following a pressure increase caused by the solvent introduced from the solvent supply unit.

In an exemplary embodiment, the biomass mixing unit may include: a first solvent supply adjustment means configured to adjust supply of the solvent introduced from the solvent supply unit; a pressure release adjustment means configured to lower pressure in the biomass mixing unit; and a biomass transfer adjustment means configured to adjust transfer of the biomass mixed with the solvent to the biomass fractionation unit.

In an exemplary embodiment, the biomass fractionation unit may include: a continuous solvent supply means; an extrusion means configured to transfer the biomass mixed with the solvent in a horizontal direction and to crush and fractionate the biomass; a heating means formed in a horizontal direction with the extrusion means and configured to adjust a temperature of the extrusion means; a fraction flow direction changing means formed at a rear side of the extrusion means and configured to change a fraction flow direction; and a fraction transfer adjustment means configured to transfer a fraction, whose flow direction has been changed by the fraction flow direction changing means, to the solid collection unit located below in a free-fall manner.

In an exemplary embodiment, a solid movement and a liquid movement in the apparatus may have different speeds, and the solid movement may be adjusted by a supply amount of biomass and/or a rotational speed of the extrusion means, and the liquid movement may be adjusted by a flow rate and/or flow speed of a solvent supplied through the continuous solvent supply means.

In an exemplary embodiment, the fractionation may be performed at 10 to 30 bar and 150 to 200° C.

In an exemplary embodiment, the extrusion means may be a screw extruder.

In an exemplary embodiment, the biomass fractionation unit may further include: a driving means configured to drive the extrusion means; and a shaft sealing means configured to seal the extrusion means.

In an exemplary embodiment, the solid collection unit may include: a solid fraction discharge adjustment means configured to adjust discharge of the solid fraction; a solid fraction collection container formed in connection with the solid fraction discharge adjustment means and configured to collect the discharged solid fraction; and a liquid fraction transfer adjustment means configured to adjust transfer of the liquid fraction to the liquid collection unit.

In an exemplary embodiment, the solid collection unit may further include a second solvent supply adjustment means for pressure correction.

In an exemplary embodiment, the liquid collection unit may include: a filter means configured to filter the liquid fraction introduced through the liquid fraction transfer adjustment means; a liquid fraction discharge adjustment means configured to adjust discharge of the liquid fraction filtered by the filter means; a liquid fraction collection container formed in connection with the liquid fraction discharge adjustment means and configured to collect the discharged liquid fraction; and a bypass means formed separately from the liquid fraction discharge adjustment means and configured to allow the filtered liquid fraction to be transferred to the liquid fraction collection container.

In an exemplary embodiment, a temperature of the biomass fractionation unit may be 150 to 200° C., and a temperature of the liquid collection unit may be 50° C. or less.

In an exemplary embodiment, the apparatus may separate reactive lignin from biomass.

In an exemplary embodiment, the reactive lignin may include β-O-4 ether bonds.

In an exemplary embodiment, the reactive lignin may include 20% or more of β-O-4 ether bonds, based on a total number of β-O-4 ether bonds contained in raw biomass before a fractionation reaction.

In an exemplary embodiment, the solvent may include an alcohol having a carbon number of 1 to 6.

In an exemplary embodiment, the solvent may be an aqueous solution having an alcohol concentration of 5 to 95 vol %.

In an exemplary embodiment, the apparatus may be capable of continuous operation.

In another aspect, the present disclosure is directed to providing a biomass fractionation method using the biomass fractionation apparatus.

In one aspect, the technology disclosed in the present disclosure has an effect of providing a biomass fractionation apparatus capable of continuous operation.

The apparatus has an effect in that a biomass accumulation phenomenon is prevented by separating the supply paths of solid biomass and high-temperature solvent, and biomass immersed in the solvent reaches the biomass fractionation unit in a free-fall manner by including the biomass supply unit, biomass mixing unit, and biomass fractionation unit in a vertical structure, and biomass is moved by an extrusion means, and the residence time in the fractionation unit may be optimized through adjustment of rotational speed, temperature, and/or supply amount, thereby achieving an effect of maximizing the yield of reactive lignin.

The biomass fractionation apparatus according to the present disclosure has an effect in that effective refinery of herbaceous and ligneous biomass is possible through the fractionation of cellulose, hemicellulose, and lignin.

Conventionally, lignin obtained through harsh fractionation processes such as high temperature and high pressure has a very low reactivity due to an irreversible degradation process in which the β-O-4 ether bond is broken and additional condensation reactions occur. In contrast, the biomass fractionation apparatus according to the present disclosure has an effect of enabling fractionation and separation of lignin, which is highly reactive due to the large amount of β-O-4 ether bonds retained.

In another aspect, the technology disclosed in the present disclosure has an effect of providing a biomass fractionation method using the biomass fractionation apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a flowchart of biomass fractionation according to one embodiment.

FIG. 2 illustrates a schematic diagram of a biomass fractionation apparatus according to one embodiment.

FIG. 3 illustrates fractionation yield of Quercus mongolica and fractionated amount by each component according to ethanol concentration, according to one embodiment.

FIG. 4 illustrates component analysis results of solid fraction and liquid fraction after fractionation of Quercus mongolica using an ethanol aqueous solution having a concentration of 50 vol %, according to one embodiment.

DETAILED DESCRIPTION OF THE INVENTION

Hereinafter, the present disclosure will be described in detail.

The terms used in the present specification are used only for the purpose of describing particular embodiments and are not intended to limit the present disclosure. Singular expressions include plural expressions unless clearly described as different meanings in the context. In the present specification, the terms “comprises”, “has” or other variations thereof are inclusive and therefore specify the presence of stated features, integers, steps, operations, elements, components, and/or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by those skilled in the art to which the present disclosure pertains. The terms such as those defined in a commonly used dictionary should be interpreted as having meanings consistent with meanings in the context of related technologies and should not be interpreted as ideal or excessively formal meanings unless explicitly defined in the present specification.

In one aspect, the present disclosure provides a biomass fractionation apparatus.

FIG. 1 illustrates a flowchart of biomass fractionation according to one embodiment, and FIG. 2 illustrates a schematic diagram of a biomass fractionation apparatus according to one embodiment.

The apparatus includes: a biomass supply unit 2; a biomass mixing unit 5 that is formed below the biomass supply unit, into which biomass supplied from the biomass supply unit is introduced; a solvent supply unit 1 that is formed separately from the biomass supply unit and supplies a solvent to the biomass mixing unit; a biomass fractionation unit 6 that is formed below the biomass mixing unit, to which biomass mixed with the solvent in the biomass mixing unit is transferred, and in which cellulose, hemicellulose, and lignin are fractionated; a solid collection unit 7 that is formed below the biomass fractionation unit and collects a solid fraction introduced from the biomass fractionation unit; and a liquid collection unit 8 that is formed in connection with the solid collection unit and collects a liquid fraction introduced from the biomass fractionation unit.

The biomass is supplied to the biomass mixing unit 5 at atmospheric pressure, and then transferred from the biomass mixing unit 5 to the biomass fractionation unit 6 in a free-fall manner, following a pressure increase caused by the solvent introduced from the solvent supply unit 1.

The present disclosure, unlike the conventional method of slurring biomass using a solvent and supplying it using a pump, has an effect of supplying solid biomass and liquid solvent through respective supply units and transferring the biomass by free fall, thereby having an effect of preventing bridge formation (biomass accumulation phenomenon) that occurs in the high-pressure transfer process of solid biomass. In addition, the present disclosure has an effect that drying, hydration, and fibrillation processes of biomass are not required.

In an exemplary embodiment, the biomass mixing unit 5 may include: a first solvent supply adjustment means 5-1 that adjusts the supply of a solvent introduced from the solvent supply unit; a pressure release adjustment means 5-2 that lowers pressure in the biomass mixing unit; and a biomass transfer adjustment means 5-3 that adjusts the transfer of biomass mixed with the solvent to the biomass fractionation unit.

In an exemplary embodiment, the solvent supply unit 1 may supply a solvent to the biomass mixing unit 5 through the first solvent supply adjustment means 5-1.

In an exemplary embodiment, the solvent supply unit 1 may supply a heated solvent to the biomass mixing unit 5 through the first solvent supply adjustment means 5-1.

In an exemplary embodiment, the solvent supply unit 1 may supply a solvent heated through a pump 3 and a preheating device 4 to the biomass mixing unit 5.

In an exemplary embodiment, the biomass supply unit 2 may supply biomass to the biomass mixing unit 5 through a biomass supply adjustment means 2-1.

In an exemplary embodiment, the biomass supply adjustment means 2-1 may be a ball valve.

In an exemplary embodiment, the first solvent supply adjustment means 5-1 may function as a pressure switching valve, and may be an inlet valve. The first solvent supply adjustment means may perform a function of pressure correction by increasing the pressure inside the biomass mixing unit 5 through the supply of a solvent by a pump.

In an exemplary embodiment, the pressure release adjustment means 5-2 may function as a pressure switching valve, and may be a pressure releasing drain valve.

In an exemplary embodiment, the biomass transfer adjustment means 5-3 may be a ball valve.

In an exemplary embodiment, the supply and transfer of biomass may be performed by the biomass supply adjustment means 2-1, the first solvent supply adjustment means 5-1, the pressure release adjustment means 5-2, and the biomass transfer adjustment means 5-3.

In an exemplary embodiment, the biomass may be supplied from the biomass supply unit 2 to the biomass mixing unit 5 by opening the biomass supply adjustment means 2-1, after lowering the pressure inside the biomass mixing unit 5 by opening the pressure release adjustment means 5-2 while the biomass supply adjustment means 2-1, the first solvent supply adjustment means 5-1, and the biomass transfer adjustment means 5-3 are in a closed state.

In an exemplary embodiment, after biomass is supplied from the biomass supply unit, the first solvent supply adjustment means 5-1 may be opened to increase the pressure through the injection of the solvent while the biomass supply adjustment means 2-1, the pressure release adjustment means 5-2, and the biomass transfer adjustment means 5-3 are in a closed state, and then the first solvent supply adjustment means 5-1 may be closed and the biomass transfer adjustment means 5-3 may be opened to transfer the biomass mixed with the solvent from the biomass mixing unit 5 to the biomass fractionation unit 6 in a free-fall manner. That is, the transfer from the biomass mixing unit 5 to the biomass fractionation unit 6 may be a transfer in a vertical direction. In this case, the solvent may be continuously supplied through a continuous solvent supply means 6-1 via a pump and a preheating device.

In an exemplary embodiment, the biomass fractionation unit 6 may include: a continuous solvent supply means 6-1; an extrusion means 6-4 that horizontally transfers, crushes, and fractionates biomass mixed with a solvent; a heating means 6-5 that is formed in a horizontal direction with the extrusion means and adjusts the temperature of the extrusion means; a fraction flow direction changing means 6-6 that is formed at a rear side of the extrusion means and changes a fraction flow direction; and a fraction transfer adjustment means 6-7 that transfers the fraction, whose flow direction has been changed by the fraction flow direction changing means, to the solid collection unit located below in a free-fall manner.

In an exemplary embodiment, the biomass fractionation unit 6 may further include: a driving means 6-2 for driving the extrusion means; and a shaft sealing means 6-3 for sealing the extrusion means.

In an exemplary embodiment, the continuous solvent supply means 6-1 may continuously supply a heated solvent, and may be an inlet valve. The continuous solvent supply means 6-1 may perform a function of pressure correction by continuously supplying a heated solvent by a pump.

In an exemplary embodiment, the continuous solvent supply means 6-1 may supply a heated solvent to the biomass fractionation unit 6.

In an exemplary embodiment, the continuous solvent supply means 6-1 may supply a heated solvent to the biomass fractionation unit 6 via a pump and a preheating device.

In an exemplary embodiment, the driving means 6-2 may be a motor.

In an exemplary embodiment, the shaft sealing means 6-3 may be a sealing means capable of withstanding a high-temperature and high-pressure solution environment, and may be a V-shape series seal. For example, it may be preferred that the sealing means be configured with a V-shape ring in series using a plastic (e.g., PEEK) that withstands high temperature, and the surrounding housing be installed with a jacket for cooling, through which cooling water flows.

In an exemplary embodiment, the extrusion means 6-4 may be a screw extruder. The biomass transferred through free fall is transferred in a horizontal direction by the extrusion means under a high-temperature and high-pressure solution environment.

In an exemplary embodiment, the residence time of the biomass in the biomass fractionation unit under high temperature and high pressure may be optimized through adjustment of the rotational speed of the screw extruder and the supply amount of the biomass. Accordingly, there is an effect of maximizing the yield of reactive lignin.

In the present disclosure, the extrusion means only functions to transfer slurried biomass, and thus has an effect of not affecting biomass particles without applying pressure load. In addition, the present disclosure has an effect of maintaining the reactivity of lignin as much as possible by using an organic solvent aqueous solution rather than a basic solution and through continuous operation that minimizes the residence time in a high-temperature section in the biomass fractionation unit.

In an exemplary embodiment, the particle size of the solid fraction discharged by crushing and fractionating in the extrusion means may be reduced by about 50% compared to the original size.

In an exemplary embodiment, scaling up may be possible depending on the scale of the extrusion means.

In an exemplary embodiment, the heating means 6-5 may be a heater.

In an exemplary embodiment, the fraction flow direction changing means 6-6 may be a guiding brush. The fraction flow direction changing means changes the flow direction of the fraction to transfer the fraction transferred by the extrusion means to the solid collection unit in a free-fall manner.

In an exemplary embodiment, the fraction transfer adjustment means 6-7 may be a ball valve. The fraction refers to a material after the fractionation reaction through the extrusion means, and the fraction is transferred to the solid collection unit through the fraction transfer adjustment means.

In an exemplary embodiment, a solid movement and a liquid movement in the apparatus may have different speeds, and the solid movement may be adjusted by the supply amount of biomass and/or the rotational speed of the extrusion means, and the liquid movement may be adjusted by the flow rate and/or flow speed of the solvent supplied through the continuous solvent supply means. The biomass fractionation apparatus of the present disclosure may adjust the residence time of liquid and solid in a high-temperature portion, i.e., in the biomass fractionation unit, respectively, in order to secure reactive lignin. Specifically, the biomass fractionation apparatus may adjust the residence time of liquid in the biomass fractionation unit to be shorter. Accordingly, by varying the residence time of the solid biomass and the liquid solvent in the biomass fractionation unit, there is an effect of maximizing the yield of reactive lignin by allowing the fractionated lignin to no longer remain in a high-temperature state, thereby preventing condensation of the fractionated lignin.

In an exemplary embodiment, the temperature of the biomass fractionation unit 6 may be 150 to 200° C.

In an exemplary embodiment, the fractionation may be performed at 10 to 30 bar and 150 to 200° C.

In an exemplary embodiment, the biomass supply unit 2, the biomass mixing unit 5, and the biomass fractionation unit 6 may be formed in a vertical structure sequentially.

In an exemplary embodiment, the solid collection unit 7 may include: a solid fraction discharge adjustment means 7-2 the adjusts the discharge of solid fraction; a solid fraction collection container 7-4 that is formed in connection with the solid fraction discharge adjustment means and collects the discharged solid fraction; and a liquid fraction transfer adjustment means 7-3 that adjusts the transfer of liquid fraction to the liquid collection unit.

In an exemplary embodiment, the solid collection unit 7 may further include a second solvent supply adjustment means 7-1 for pressure correction.

In an exemplary embodiment, the second solvent supply adjustment means 7-1 may be an inlet valve. The second solvent supply adjustment means may perform a function of pressure correction through the supply of a solvent by a pump.

In an exemplary embodiment, the second solvent supply adjustment means 7-1 may supply a heated solvent to the solid collection unit 7.

In an exemplary embodiment, the second solvent supply adjustment means 7-1 may supply a heated solvent to the solid collection unit 7 via a pump and a preheating device.

In an exemplary embodiment, the solid fraction discharge adjustment means 7-2 may be a ball valve.

In an exemplary embodiment, the liquid fraction transfer adjustment means 7-3 may be a ball valve.

In an exemplary embodiment, the solid fraction may be moved to the solid fraction collection container 7-4 by opening the solid fraction discharge adjustment means 7-2 while the fraction transfer adjustment means 6-7, the second solvent supply adjustment means 7-1, and the liquid fraction transfer adjustment means 7-3 are in a closed state. For example, the solid fraction may have its flow direction changed through the fraction flow direction changing means 6-6, and may be transferred to the solid collection unit 7 in a free-fall manner through the fraction transfer adjustment means 6-7, and also may be moved in a free-fall manner to an external solid fraction collection container 7-4 and stored.

In an exemplary embodiment, for pressure reinforcement, after the fraction transfer adjustment means 6-7, the solid fraction discharge adjustment means 7-2, and the liquid fraction transfer adjustment means 7-3 are closed, a solvent may be supplied through the second solvent supply adjustment means 7-1 to apply pressure, and when the system pressure is reached, the second solvent supply adjustment means 7-1 may be closed, and the fraction transfer adjustment means 6-7 and the liquid fraction transfer adjustment means 7-3 may be opened to maintain continuous operation.

In an exemplary embodiment, the temperature of the solid collection unit 7 may be lower than the temperature of the biomass fractionation unit 6 by being cooled by air cooling.

In an exemplary embodiment, the temperature of the solid collection unit 7 may be 150° C. or less, or less than 150° C., for example, 60 to 100° C.

In an exemplary embodiment, the liquid collection unit 8 may include: a filter means 8-1 that filters the liquid fraction introduced through the liquid fraction transfer adjustment means; a liquid fraction discharge adjustment means 8-2 that adjusts the discharge of the filtered liquid fraction by the filter means; a liquid fraction collection container 8-4 that is formed in connection with the liquid fraction discharge adjustment means and collects the discharged liquid fraction; and a bypass means 8-3 that is formed separately from the liquid fraction discharge adjustment means and configured to allow the filtered liquid fraction to be transferred to the liquid fraction collection container.

In an exemplary embodiment, the filter means 8-1 may be a sintered metal filter formed in a metal particle sintering manner.

In an exemplary embodiment, the liquid fraction discharge adjustment means 8-2 may be a relief valve or back pressure regulator. By discharging liquid through the liquid fraction discharge adjustment means, the system pressure in the apparatus may be maintained constant. In an exemplary embodiment, the bypass means 8-3 may be a bypass valve.

In an exemplary embodiment, the liquid fraction introduced into the liquid collection unit 8 through the liquid fraction transfer adjustment means 7-3 may be discharged to the outside at atmospheric pressure through the liquid fraction discharge adjustment means 8-2 by passing through the filter means 8-1.

In an exemplary embodiment, the flow rate of the liquid fraction may be adjusted by a pump (not illustrated). For example, the liquid flow rate in the apparatus may be adjusted by a pump to optimize the residence time in the biomass fractionation unit under high temperature and high pressure for improvement of the fractionation yield of lignin and securing of reactive lignin.

In an exemplary embodiment, the liquid collection unit 8 may be relatively lower in temperature than the system temperature in the apparatus, thereby having an effect of maintaining the reactivity of lignin as much as possible.

In an exemplary embodiment, the temperature of the liquid collection unit 8 may be a low temperature of 50° C. or less, for example, room temperature to 40° C. The biomass fractionation apparatus of the present disclosure may reduce the residence time of the solvent in the high-temperature portion, compared to a conventional batch-type fractionation apparatus, and accordingly, may have an effect of separating reactive lignin from biomass with a high yield.

In an exemplary embodiment, the continuous solvent supply means may continuously supply a solvent, and the first solvent supply adjustment means and the second solvent supply adjustment means may supply the solvent only when pressure correction is needed.

In an exemplary embodiment, the system pressure in the apparatus may be maintained by the liquid fraction discharge adjustment means.

In an exemplary embodiment, the system temperature in the apparatus may be maintained by the solvent that is preheated and supplied, and by the heating means.

In an exemplary embodiment, the biomass may be ligneous or herbaceous.

In an exemplary embodiment, the biomass may be lignocellulose.

In an exemplary embodiment, the biomass may have a size smaller than the inner diameter of a tube through which the biomass is transferred and the pitch of the extrusion means.

In an exemplary embodiment, the apparatus may be capable of continuous collection of the solid fraction and the liquid fraction.

In an exemplary embodiment, the solid fraction may include cellulose.

In an exemplary embodiment, the solid fraction may include cellulose in 60 wt % or more, 65 wt % or more, or 70 wt % or more, and 80 wt % or less, 75 wt % or less, or 70 wt % or less, based on the total weight of the solid fraction.

In an exemplary embodiment, the liquid fraction may include hemicellulose and lignin.

In an exemplary embodiment, the liquid fraction may include hemicellulose in 25 wt % or more, 26 wt % or more, 27 wt % or more, 28 wt % or more, 29 wt % or more, or 30 wt % or more, and 45 wt % or less, 40 wt % or less, 35 wt % or less, or 30 wt % or less, based on the total weight of the liquid fraction.

In an exemplary embodiment, the liquid fraction may include lignin in 30 wt % or more, 35 wt % or more, 40 wt % or more, or 45 wt % or more, and 60 wt % or less, 55 wt % or less, or 50 wt % or less, based on the total weight of the liquid fraction.

Lignin is a copolymer of three phenylpropane monomers. The bonding forms of these monomers are various, but the β-aryl ether (β-O-4) bonds are the most common, accounting for 46 to 60%.

In an exemplary embodiment, the apparatus may separate reactive lignin from biomass. In an exemplary embodiment, the reactive lignin may include β-O-4 ether bonds.

In an exemplary embodiment, the reactive lignin may include 20% or more, or 20% to 80% of β-O-4 ether bonds, based on the total number of β-O-4 ether bonds contained in the raw biomass before the fractionation reaction. In another exemplary embodiment, the reactive lignin may include 20% or more, 25% or more, 30% or more, 35% or more, 40% or more, 45% or more, 50% or more, 55% or more, 60% or more, 65% or more, 70% or more, or 75% or more, and 80% or less, 75% or less, 70% or less, 65% or less, 60% or less, 55% or less, 50% or less, 45% or less, 40% or less, 35% or less, 30% or less, or 25% or less, of the number of β-O-4 ether bonds, based on the total number of β-O-4 ether bonds contained in the raw biomass before the fractionation reaction.

In an exemplary embodiment, the solvent supplied in the apparatus may have a boiling point lower than water.

In an exemplary embodiment, the solvent supplied in the apparatus may include an alcohol having a carbon number of 1 to 6.

In an exemplary embodiment, the solvent may include ethanol.

In an exemplary embodiment, the solvent may be an aqueous solution having an alcohol concentration of 5 to 95 vol %. In another exemplary embodiment, the solvent may be an aqueous solution having an alcohol concentration of 5 vol % or more, 10 vol % or more, 15 vol % or more, 20 vol % or more, 25 vol % or more, 30 vol % or more, 35 vol % or more, 40 vol % or more, 45 vol % or more, 50 vol % or more, 55 vol % or more, 60 vol % or more, 65 vol % or more, 70 vol % or more, 75 vol % or more, 80 vol % or more, 85 vol % or more, or 90 vol % or more, and 95 vol % or less, 90 vol % or less, 85 vol % or less, 80 vol % or less, 75 vol % or less, 70 vol % or less, 65 vol % or less, 60 vol % or less, 55 vol % or less, 50 vol % or less, 45 vol % or less, 40 vol % or less, 35 vol % or less, 30 vol % or less, 25 vol % or less, 20 vol % or less, 15 vol % or less, or 10 vol % or less.

In an exemplary embodiment, the solvent may be recoverable and recyclable through single distillation.

In an exemplary embodiment, the apparatus may be capable of continuous operation.

In an exemplary embodiment, the apparatus may be a high-temperature and high-pressure apparatus.

In an exemplary embodiment, the apparatus may be capable of continuous fractionation of biomass at high temperature of 150 to 200° C. and high pressure of 10 to 30 bar.

In an exemplary embodiment, the apparatus may have an effect of continuously supplying biomass and continuously fractionating and separating cellulose, hemicellulose, and lignin. Such continuous operation enables the commercialization of a biorefinery with potential to replace an oil refinery.

In an exemplary embodiment, the apparatus may be capable of long-term operation. In another aspect, the present disclosure provides a biomass fractionation method using the biomass fractionation apparatus.

In an exemplary embodiment, the method may include: supplying biomass from the biomass supply unit to the biomass mixing unit at atmospheric pressure; supplying a heated solvent from the solvent supply unit to the biomass mixing unit to increase pressure in the biomass mixing unit; transferring the biomass mixed with the solvent from the biomass mixing unit to the biomass fractionation unit in a free-fall manner; fractionating cellulose, hemicellulose, and lignin in the biomass fractionation unit to obtain a fraction; and transferring the fraction to the solid collection unit and then separating a solid fraction including cellulose and a liquid fraction including hemicellulose and lignin.

In an exemplary embodiment, the biomass fractionation method according to the present disclosure is as follows.

First, the biomass is supplied from the biomass supply unit 2 to the biomass mixing unit 5 by opening the biomass supply adjustment means 2-1, after lowering the pressure inside the biomass mixing unit 5 by opening the pressure release adjustment means 5-2 while the biomass supply adjustment means 2-1, the first solvent supply adjustment means 5-1, and the biomass transfer adjustment means 5-3 are in a closed state. Subsequently, while the biomass supply adjustment means 2-1, the pressure release adjustment means 5-2, and the biomass transfer adjustment means 5-3 are in a closed state, the first solvent supply adjustment means 5-1 is opened to increase the pressure through the injection of the solvent, and then the first solvent supply adjustment means 5-1 is closed, and the biomass transfer adjustment means 5-3 is opened to transfer the biomass mixed with the solvent from the biomass mixing unit 5 to the biomass fractionation unit 6 in a free-fall manner.

The biomass reaching the biomass fractionation unit 6 is transferred in a horizontal direction through the extrusion means 6-4 formed in the horizontal direction, and is crushed and fractionated in a high-temperature and high-pressure environment by the extrusion means 6-4. The residence time of the biomass in the heating section may be adjusted through adjustment of the rotation speed of the extrusion means and the supply amount of the biomass. In order to transfer the fraction transferred by the extrusion means 6-4 to the lower solid collection unit 7 below in a free-fall manner, the flow direction thereof is changed by the fraction flow direction changing means 6-6.

The fraction transferred to the solid collection unit 7 is moved to the solid fraction collection container 7-4 by opening the solid fraction discharge adjustment means 7-2 in a state in which the fraction transfer adjustment means 6-7, the second solvent supply adjustment means 7-1, and the liquid fraction transfer adjustment means 7-3 are closed. For pressure reinforcement, after the fraction transfer adjustment means 6-7, the solid fraction discharge adjustment means 7-2, and the liquid fraction transfer adjustment means 7-3 are closed, a solvent is supplied through the second solvent supply adjustment means 7-1 to apply pressure, and when the system pressure is reached, the second solvent supply adjustment means 7-1 is closed, and the fraction transfer adjustment means 6-7 and the liquid fraction transfer adjustment means 7-3 are opened to maintain continuous operation.

The liquid fraction introduced into the liquid collection unit 8 through the liquid fraction transfer adjustment means 7-3 passes through the filter means 8-1 and is discharged to the outside at atmospheric pressure through the liquid fraction discharge adjustment means 8-2, and is stored in the liquid fraction collection container 8-4. In the apparatus, the residence time of the liquid in the biomass fractionation unit 6 may be adjusted by adjusting the flow rate using a pump. In addition, the system pressure may be adjusted by the liquid fraction discharge adjustment means 8-2 to minimize solid clogging or jamming.

In an exemplary embodiment, the separated cellulose pulp may be used as a lignocellulose fiber precursor and a carbon fiber precursor.

In an exemplary embodiment, the separated cellulose pulp may be applied to a fermentation process of monosaccharides through a saccharification process.

In an exemplary embodiment, the separated cellulose pulp may be converted into a monomer for bioplastic synthesis through a chemical cellulose conversion process.

In an exemplary embodiment, the separated reactive lignin powder may be converted into propyl-, ethyl-, methyl-phenol/cyclohexane through depolymerization and deoxygenation.

In an exemplary embodiment, the separated reactive lignin powder may be applicable as a sustainable aviation fuel (SAF, Biofuel for aviation) and a liquid organic hydrogen carrier (LOHC) mixture according to boiling point.

In an exemplary embodiment, the separated hemicellulose powder may be applicable to a monosaccharide fermentation process through a saccharification process.

In an exemplary embodiment, the separated hemicellulose powder may be usable as a hydrogen donor through liquid-phase reforming in the depolymerization and deoxygenation process of reactive lignin.

Hereinafter, the present disclosure will be described in more detail through examples. These embodiments are just illustrative of the present disclosure, and it is apparent to one of ordinary skill in the art that the scope of the present disclosure is not to be interpreted as limited by these embodiments.

Example

A prepared organic solvent aqueous solution 1 was injected into the biomass mixing unit 5 via the pump 3 and the preheating device 4, and biomass was directly supplied from the biomass supply unit 2 to the biomass mixing unit 5. The biomass mixing unit 5 allows pressure adjustment using a valve and an auxiliary pump, so after the biomass was supplied at atmospheric pressure, it reached the biomass fractionation unit 6 in a free-fall manner within the pressurized solvent. The biomass that reached the biomass fractionation unit 6 together with the solvent was crushed and fractionated while passing through a screw extruder of high temperature. In this case, reactive lignin was selectively fractionated by the organic solvent and water.

Under high-temperature and high-pressure conditions of 185° C. and 20 bar, Quercus mongolica was fractionated through continuous operation, and the fractionation yield of Quercus mongolica depending on ethanol concentration and the fractionated amount of each component were calculated from the solid fraction and shown in FIG. 3. As a result of continuous operation fractionation, the fractionation yield of the solid fraction was maintained at about 45 to 50 wt % at an ethanol concentration of 25 to 75 vol %. The lignin fractionated amount (i.e., delignification) reached 85% to 90% of the originally contained lignin amount.

Meanwhile, since the hemicellulose retention in the solid fraction (i.e., xylan retention) was 10% to 30%, it was confirmed that the hemicellulose fractionated amount was 70% to 90% of the originally contained hemicellulose amount and was fractionated in the liquid phase together with lignin. The cellulose retention in the solid fraction (i.e., glucan retention) was 80 to 90%, and thus most of the cellulose was present in the solid pulp, and it was confirmed that the cellulose fractionated amount was 10 to 20% of the originally contained cellulose amount.

The reactivity of lignin is determined by the remaining amount of β-aryl ether (β-O-4) bonds of Chemical Formula 1 below, and as a result of HSQC-NMR (DD2 600 MHz FT NMR, Agilent Technologies, USA) analysis, the β-O-4 ether bonds present in the raw biomass (Quercus mongolica) were found to be 60.69 (MWL) out of 100 aromatics (refer to Table 1 below). After the continuous operation fractionation of the above Quercus mongolica, in case of the fraction using an ethanol aqueous solution of 25 to 75 vol %, it was confirmed that about 19 to 26 β-O-4 ether bonds were retained. Meanwhile, in a comparative example, in case of kraft lignin (KL), which is generally fractionated using a basic solution, it was confirmed that about 5 β-O-4 ether bonds remained.

	TABLE 1
				EtOH	EtOH	EtOH
				25/H2O	50/H2O	75/H2O
	MWLa	KLb	H2O	75	50	25	EtOH

β-O-4	60.69	4.76	10.75	19.19	20.84	25.56	27.22
β-β	8.82	3.11	4.41	5.51	5.99	6.38	6.40
β-5	3.50	0.51	0.84	0.85	1.19	1.38	1.46
aMilled wood lignin,
bkraft lignin

During the continuous operation fractionation experiment of Quercus mongolica, the components of the solid fraction and the liquid fraction of the experimental group using an organic solvent aqueous solution including 50 vol % ethanol as the solvent was analyzed, and the results are shown in FIG. 4. As a result, based on the total weight of the fraction, 49.5 wt % of the solid fraction and 43.7 wt % of the liquid fraction were obtained. The solid fraction was in the form of solid pulp, as shown in the upper photograph of FIG. 4, and 73.1 wt % of the solid fraction consisted of cellulose. The lower photograph in FIG. 4 shows the liquid fraction after the solvent was evaporated, and 49.7 wt % of the liquid fraction consisted of lignin, and 32.7 wt % consisted of hemicellulose.

In addition, as described above, Quercus mongolica was fractionated by continuous operation, and continuous operation fractionation was performed under high-temperature and high-pressure conditions of 185° C. and 10 to 30 bar, using an organic solvent aqueous solution including 50 vol % ethanol as the solvent. The fractionation yield of Quercus mongolica and the fractionation yield of each component were calculated from the liquid fraction and are shown in Table 2. The fractionation yield of the liquid fraction was maintained at 27.0 to 51.0 wt %, and the lignin fractionation yield reached 63% to 95% of the originally contained lignin amount. The hemicellulose fractionation yield was 51.0% to 87.1% of the originally contained hemicellulose amount, and it was fractionated in the liquid phase together with lignin. The cellulose fractionation yield was 8% to 18% of the originally contained cellulose amount, and it was confirmed that 82% to 92% thereof were present in the solid pulp.

	TABLE 2
	10 bar	20 bar	30 bar

Fractionation yield	27.0	43.0	51.0
Cellulose fractionation yield	8.0	18.0	11.0
Hemicellulose fractionation yield	51.0	72.7	87.1
Lignin fractionation yield	63.0	73.0	95.0

The above describes specific aspects of the present disclosure in detail. It will be apparent to those skilled in the art that these specific techniques are merely preferred embodiments and that the scope of the present disclosure is not limited thereby. Therefore, the substantial scope of the present disclosure is defined by the appended claims and their equivalents.

DESCRIPTION OF REFERENCE NUMERALS

• • 1; Solvent supply unit
  • 2; Biomass supply unit 2-1; Biomass supply adjustment means
  • 3; Pump 4; Preheating device
  • 5; Biomass mixing unit 5-1; First solvent supply adjustment means
  • 5-2; Pressure release adjustment means
  • 5-3; Biomass transfer adjustment means
  • 6; Biomass fractionation unit 6-1; Continuous solvent supply means
  • 6-2; Driving means 6-3; Shaft sealing means
  • 6-4; Extrusion means 6-5; Heating means
  • 6-6; Fraction flow direction changing means
  • 6-7; Fraction transfer adjustment means
  • 7; Solid collection unit 7-1; Second solvent supply adjustment means
  • 7-2; Solid fraction discharge adjustment means
  • 7-3; Liquid fraction transfer adjustment means
  • 7-4; Solid fraction collection container
  • 8; Liquid collection unit 8-1; Filter means
  • 8-2; Liquid fraction discharge adjustment means 8-3; Bypass means
  • 8-4; Liquid fraction collection container