JP2017063749A - Method for producing lignocellulosic biomass-derived compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus and method for producing a lignocellulosic biomass-derived compound, which allow a fermentation inhibitory substance to be inexpensively and effectively eliminated.SOLUTION: The present invention provides a method for producing a lignocellulosic biomass-derived compound, the method comprising the steps of: (A) generating an acid digestion product by a hydrolysis treatment in which lignocellulosic biomass is mixed and digested with acid in a hydrolysis tank; (M) vaporization-removing a fermentation inhibitor by subjecting the acid digestion product to a drying treatment in a drying treatment tank; (N) adding ammonia to the dried acid digestion product in an ammonia addition tank to further reduce the fermentation inhibitor and adjust the pH of the digestion product subjected to the drying treatment; and (B) performing a saccharification process in which a saccharified solution containing monosaccharides and/or oligosaccharides is produced from the acid digestion product after the addition of ammonia by the enzyme in a saccharification tank.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a production method and a production apparatus for a lignocellulosic biomass-derived compound.

  In recent years, from the viewpoint of global warming countermeasures and effective utilization of waste, the use of biomass using plant resources as a raw material has attracted attention. In general, sugars such as sugar cane and starches such as corn are often used as raw materials for producing a compound such as ethanol from biomass. However, these raw materials are originally used as food or feed, and long-term utilization as industrial resources may cause competition with food or feed use and may cause a rise in raw material prices.

  Therefore, technology development that uses non-edible biomass as an energy resource is being promoted. Non-edible biomass includes the most abundant cellulose on the earth, most of which exists as lignocellulose, which is a complex with the aromatic polymer lignin and hemicellulose. This lignocellulose has a structure in which cellulose, hemicellulose, and lignin are firmly bound, and it is not easy to be decomposed into a pentose or hexose monosaccharide or oligosaccharide that can be used for fermentation.

  So far, pretreatment methods for treating lignocellulosic biomass using acids, alkalis, enzymes, supercritical water, etc. to break or soften the lignin barrier have been studied. For example, the treatment with supercritical water has an advantage that a by-product is not generated because the treatment time is short and neutralization treatment is not required. However, because of its high reactivity, it is difficult to control, such as furfural and 5-hydroxymethylfurfural, which are sugar degradants, vanillin and guaiacol, which are aromatic compounds derived from lignin, acetic acid derived from hemicellulose, formic acid, repric acid, etc. The problem was that fermentation inhibitors were also generated at the same time.

International Publication No. 2009/110374 JP 2004-187650 A Special table 2012-504935 gazette

  As a method for removing fermentation-inhibiting substances, Patent Document 1 proposes removal using a separation membrane having an average pore diameter of 0.8 to 4.0 mm. However, since the hole diameter is very fine, an operating pressure of 0.5 MPa is required, resulting in high equipment costs. Furthermore, the xylose and oligosaccharides produced in the pretreatment cannot pass through the pore diameter, causing a reduction in the yield of the sugar solution.

  Patent Document 2 proposes removal of a fermentation inhibitor by evaporation of sugar solution. The removal method by evaporation is excellent in that it is inexpensive and can be removed in a short time. However, furfural and acetic acid having a relatively low melting point can be removed, but 5-hydroxymethylfurfural and formic acid cannot be removed.

  Furthermore, Patent Document 3 proposes pH adjustment by addition of alkali and removal of a fermentation inhibitor in a vacuum environment. In the fermentation process, it is preferred that the pH is in the neutral range, and by applying a vacuum, volatile furfural and acetic acid can be removed as in Patent Document 2, but 5-hydroxymethylfurfural and formic acid are removed. Can not do it.

  This invention is made | formed in view of the said situation, Comprising: It aims at providing the manufacturing method and manufacturing apparatus of a lignocellulosic biomass origin compound which remove a fermentation inhibitor effectively at low cost.

That is, the present invention is as follows.
(1) A method for producing a lignocellulosic biomass-derived compound,
(A) a step of producing an acid cooked product by hydrolysis by mixing an acid with lignocellulosic biomass and cooking;
(M) drying the acid-boiled product to volatilize and remove the fermentation inhibitor;
(N) adding ammonia to the dried acid cooked product, further reducing fermentation inhibiting substances, and adjusting the pH of the dried cooked product;
(B) a saccharification step for producing a saccharified solution containing monosaccharides and / or oligosaccharides from the acid-boiled product after addition of ammonia by the enzyme;
A process for producing a lignocellulosic biomass-derived compound, comprising:
(2) The method for producing a lignocellulose-based biomass-derived compound according to (1), wherein the step (N) and the step (B) are performed simultaneously.
(3) The step (N)
(X) having an initial saccharification step in which the dried acid-boiled product and ammonia are continuously added little by little to the first saccharification tank previously containing the enzyme,
Instead of the step (B),
(Y) having a saccharification step of continuously adding the saccharified solution produced in the initial saccharification step little by little to a second saccharification tank preliminarily containing an enzyme;
(1) The manufacturing method of the lignocellulosic biomass origin compound as described in (2).
(4) The ligno according to any one of (1) to (3), wherein the content of the fermentation-inhibiting substance is reduced below a threshold value that does not cause fermentation inhibition by the step (M) and the step (N). A method for producing a cellulosic biomass-derived compound.
(5) Any one of (1) to (4), wherein a target value for reducing the content of the fermentation inhibitor in the step (M) is set on the basis of the content of the fermentation inhibitor after the step (N). The manufacturing method of the lignocellulosic biomass origin compound as described in one.
(6) Any one of (1) to (5), wherein the water content in the acid cooked product after step (M) is 1.00 kg to 2.58 kg with respect to 1 kg of the dried lignocellulosic biomass. The manufacturing method of the lignocellulosic biomass origin compound as described in one.
(7) A device for producing a lignocellulosic biomass-derived compound,
A hydrolysis treatment tank for producing an acid cooked product by hydrolysis by mixing an acid with lignocellulosic biomass and cooking,
A drying treatment tank for drying the acid-boiled product to volatilize and remove the fermentation inhibitor;
Adding ammonia to the dried acid cooked product, an ammonia addition tank for further reducing fermentation inhibiting substances,
A saccharification tank for producing a saccharified solution containing monosaccharides and / or oligosaccharides from the acid-boiled product after addition of ammonia by the enzyme;
An apparatus for producing a lignocellulosic biomass-derived compound, comprising:
(8) The lignocellulosic biomass-derived compound production apparatus according to (7), wherein the ammonia addition tank and the saccharification tank are combined into one saccharification tank.
(9) The lignocellulosic biomass-derived compound production according to (7) or (8), wherein the ammonia addition tank preliminarily containing an enzyme is the first saccharification tank and the saccharification tank is the second saccharification tank. apparatus.
(10) The content of the fermentation inhibitor is reduced to a threshold value that does not cause fermentation inhibition by treatment in the drying treatment tank and the ammonia addition tank, according to any one of (7) to (9). Lignocellulose-based biomass-derived compound production equipment.
(11) Based on the content of the fermentation inhibiting substance after the ammonia addition tank, a reduction target value of the content of the fermentation inhibiting substance in the drying treatment tank is set as any one of (7) to (10) The lignocellulosic biomass-derived compound production apparatus described.
(12) Any one of (7) to (11), wherein the water content in the acid cooked product after the drying treatment tank is 1.00 kg or more and 2.58 kg or less with respect to 1 kg of the dried lignocellulosic biomass. The lignocellulosic biomass-derived compound production apparatus described in 1.

  According to the method and apparatus for producing a lignocellulosic biomass-derived compound of the present invention, a fermentation inhibitor is effectively removed at low cost without using special equipment, and a lignocellulosic biomass-derived compound is efficiently obtained. be able to.

It is a figure which shows schematic structure of the manufacturing method of the lignocellulosic biomass origin compound which concerns on 1st embodiment of this invention. It is the graph which showed the evaporation curve of furfural, acetic acid, and formic acid. It is the graph which plotted the relationship between the content of furfural, 5-HMF, and an acetic acid in lignocellulosic biomass, and the yield of ethanol. It is a figure which shows schematic structure of the manufacturing method of the lignocellulosic biomass origin compound which concerns on 2nd embodiment of this invention. It is a figure which shows schematic structure of the manufacturing method of the lignocellulose biomass origin compound which concerns on 3rd embodiment of this invention. In Experiment 1, it is the graph which compared the yield of the ethanol produced | generated using the lignocellulose biomass adjusted pH with sodium hydroxide, and the lignocellulose biomass adjusted pH with ammonia. In Experiment 2, it is the graph which each showed the correlation of the content of the acetic acid which is a fermentation inhibitory substance, a furfural, and 5-HMF, and the water content. In Test Example 3, (a) is a graph showing the correlation between the moisture content and the furfural content of the acid cooked product at each drying temperature and drying time, and (b) is the acid cooked product at each drying temperature and drying time. It is the graph which showed the correlation of the water content of and the drying time. In Experiment 3, it is the graph which each showed the correlation of the water content of the acid cooked food in each drying temperature and drying time, and the content of the acetic acid which is a fermentation inhibitory substance, a furfural, and 5-HMF.

  The lignocellulosic biomass to be treated in the production method and production apparatus of the present invention mainly contains cellulose, hemicellulose, and lignin. For example, conifers, hardwoods, building waste, forest land residue, pruning waste, rice straw Agricultural and forestry product resources such as rice husk, wheat straw, wood chips, wood fiber, chemical pulp, waste paper, plywood, and other agricultural and forestry waste products such as sugarcane bagasse, sugarcane foliage, corn stover, and processed agricultural products. Contains sucrose-containing resources such as sugar cane, sugar beet, starch-containing resources such as corn, sweet potato, etc., even if they contain little or no lignin content or contain fermentation inhibitors typified by sugar hyperdegradation products or If it produces | generates, it does not matter as a process target with the manufacturing method of this invention. These lignocellulosic biomasses may be used alone or as a mixture.

  Hemicellulose is called pentose containing 5 carbons such as xylose, hexose containing 6 carbons such as mannose, arabinose and galacturonic acid, glucomannan, Since it has a complex polysaccharide such as glucuronoxylan, when it is hydrolyzed, it has five carbon pentose monosaccharides, a pentose oligosaccharide in which multiple monosaccharides are linked, and six carbons. A hexose saccharide monosaccharide consisting of a plurality of hexose saccharides and a pentose saccharide monosaccharide and a pentose saccharide monosaccharide and a hexose saccharide monosaccharide are produced. Cellulose has 6 carbons as a structural unit, so when hydrolyzed, it produces a 6-carbon monosaccharide of 6 carbons and a hexose oligosaccharide in which a plurality of monosaccharides are linked. In general, the composition ratio and production amount of monosaccharides and / or oligosaccharides vary depending on the pretreatment method and the types of agricultural and forestry product resources, agricultural and forestry product wastes and processed agricultural and forestry products used as raw materials.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each of the drawings, portions not related to the description may be omitted.

[Production method of lignocellulosic biomass-derived compound]
<First embodiment>
The method for producing a lignocellulosic biomass-derived compound according to the first embodiment of the present invention includes (A) a step of producing an acid cooked product by hydrolysis by mixing an acid with lignocellulosic biomass and steaming. (M) drying the acid cooked product to volatilize and remove the fermentation inhibitor, and (N) adding ammonia to the dried acid cooked product to further reduce the fermentation inhibitor, and And (B) a saccharification step for producing a saccharified solution containing monosaccharides and / or oligosaccharides from the acid-steamed product after addition of ammonia by the enzyme. Drawing 1 is a figure showing the schematic structure of the manufacturing method of the lignocellulosic biomass origin compound concerning a first embodiment of the present invention. Details of each step will be described below.

First, the step (A) is a pretreatment step for removing liquin or softening by mixing lignocellulosic biomass with an acid, steaming and hydrolyzing it, thereby facilitating taking out cellulose or hemicellulose. The acid is selected from sulfuric acid, hydrochloric acid, nitric acid, phosphoric acid and the like, and these may be used alone or in combination. Among them, sulfuric acid which is inexpensive and easily available is particularly preferable for industrial use.
Steaming means holding the raw material at a high pressure and high humidity for a certain period of time. Moreover, you may provide the process of exploding lignocellulosic biomass mixed with the acid after cooking. Blasting means that the high-pressure and high-humidity raw material is pulverized with an impact that opens at once.

  In this pretreatment step, the acid is 0.5% by mass to 3.0% by mass, and preferably 1.5% by mass to 2.5% by mass with respect to the dry biomass weight with respect to the solution containing lignocellulosic biomass. It is preferable to add. Moreover, it is preferable to carry out on the vapor | steam saturation conditions under the pressure of 0.4-1.5 MPaG, desirably 0.5-1.2 MPaG. Moreover, it is preferable to blast after cooking for 1.5 to 30 minutes.

  In the present invention, the “acid cooked product” means a product produced by mixing lignocellulosic biomass with an acid, cooking and hydrolyzing it. In addition to cellulose, hemicellulose, monosaccharides and / or oligosaccharides, various by-products are contained in the acid cooked product. If these by-products are substances that do not adversely affect at least one of the subsequent saccharification step and fermentation step, they are not a big problem because they can be removed in the final distillation step. However, if the fermentation inhibitor has an adverse effect, it is necessary to remove it to the extent that it does not adversely affect each step in at least one of the saccharification step and the fermentation step.

  In the present invention, the “fermentation inhibitor” is a substance that interferes with the fermentation reaction in the fermentation process. As a typical fermentation inhibitor, a compound derived from a sugar hyperdegradation product, lignin or an aromatic compound derived from lignin, an adhesive, and / or an artificial drug of paint. In this, the compound derived from the artificial chemical | medical agent of at least one of an adhesive agent and a coating material can be avoided to some extent or more by using naturally-derived lignocellulosic biomass which has not been processed. However, as long as lignocellulosic biomass is used as a raw material, it is difficult to avoid the production of sugar overdegradation products and lignin-derived aromatic compounds. Here, when the fermentation inhibitor is an insoluble solid such as lignin, and cellulose, hemicellulose, monosaccharide and / or oligosaccharide are soluble, it may be possible to remove by ordinary solid-liquid separation. . However, when both a fermentation inhibitor and a useful product are soluble, normal solid-liquid separation cannot be applied. Therefore, the treatment method for removing a fermentation inhibitor described later in the present invention is preferably applied. That is, in the present invention, the fermentation inhibitor to be treated mainly forms a mixed solution of cellulose, hemicellulose, monosaccharide and / or oligosaccharide, and in normal solid-liquid separation. Those that cannot be separated or difficult to separate. Examples of such fermentation inhibiting substances include acetic acid, formic acid, levulinic acid, a sugar hyperdegradation product furfural, 5-hydroxymethylfurfural (5-HMF), lignin-derived aromatic compound vanillin, acetovanillin , Guayacoal and so on. Among these fermentation inhibitors, typical fermentation inhibitors are acetic acid, formic acid, furfural, and 5-HMF.

  Step (M) is a step of drying the acid cooked product to volatilize and remove the fermentation inhibitor. The fermentation inhibitor having volatility can be removed by performing a drying treatment.

FIG. 2 shows the evaporation curves of furfural, acetic acid and formic acid. For 5-HMF, it is obvious that it hardly evaporates, so the published evaporation curve could not be found.
In the present invention, the concentration of the fermentation inhibitor dissolved in the acid cooked product is 1.2% or less for acetic acid, 0.3% or less for furfural, and 0.2% or less for 5-HMF or formic acid. . Moreover, each upper limit concentration in the gas phase corresponding to the upper limit concentration (acetic acid: 1.2%, furfural: 0.3%, formic acid: 0.2%) of the fermentation inhibitor dissolved in the acid cooked product is Acetic acid: 1.7%, furfural: 0.79%, formic acid: 0.15%.
The horizontal axis indicates the molar ratio of water in the liquid. For example, the horizontal axis 0.8 of the furfural evaporation curve means water 0.8 and furfural 0.2. The vertical axis represents the molar ratio of water in the gas.
The evaporation curve is a curve showing the concentration in the gas phase and the concentration in the gas phase in an equilibrium state, and the portion located below the y = x line (the region (*) in the figure) is water in aqueous solution. This shows that acetic acid and furfural dissolved in water are easier to evaporate when the water concentration in the gas phase is smaller than the concentration. On the other hand, the evaporation curve of formic acid shows that there is no portion located below the y = x line in the concentration range, so that formic acid is less likely to evaporate than water in the concentration range.
Therefore, among the by-products contained in the acid cooked product, acetic acid and furfural have volatility and can be reduced by drying.

  The temperature for drying the acid cooked product is preferably 60 ° C. or higher and 130 ° C. or lower, and more preferably 100 ° C. or higher and 110 ° C. or lower from the viewpoint of drying efficiency and cost.

  The pH of the acid cooked product in the step (M) is preferably 4 or less. Since the pKa of acetic acid, which is a fermentation inhibitor, is 4.56, if the pH of the acid cooked product to be dried is 4 or less, the acetic acid tends to volatilize and is efficient when a part of the sugar solution is evaporated. In addition, the fermentation inhibitor can be removed. This is because if the pH of the acid cooked product is the same as or lower than the pKa value of the fermentation inhibitor, the fermentation inhibitor is easily dissociated into ions and is easily removed by evaporation. If the pH is greater than 4, acetic acid, which is a fermentation inhibitor component to be removed, is difficult to volatilize, and if the pH is 8 to 9 or more, monosaccharides may be decomposed by heating. Therefore, the step (M) is performed after the step (A) and before the step (N). This is because the step (N) described later is a step of adding ammonia, and the pH becomes 5 or more.

  Step (N) is a step of adding ammonia to the dried acid cooked product to further reduce fermentation inhibiting substances and adjusting the pH of the dried cooked product.

Furfural and acetic acid were reduced in the step (M), but in the step (N), they are converted into substances that do not inhibit fermentation by reacting with ammonia including other fermentation inhibitors.
First, acetic acid and formic acid are taken up into yeast cells and inhibit the fermentation reaction, but when treated with ammonia, acetic acid and formic acid react with ammonia, respectively, and turn into ammonium acetate and ammonium formate (the following reaction). (See formulas (1) and (2)). At this time, although the reaction is in an equilibrium state, since the ionization degree of ammonium ions is low, it is difficult to produce acetic acid and formic acid that easily shift to the reaction toward ammonium acetate and ammonium formate and cause fermentation inhibition. Therefore, by changing to ammonium acetate and ammonium formate, it is not taken up into the yeast cells and does not inhibit fermentation.

  Furthermore, furfural and 5-HMF react with ammonia and iminate (dehydration decomposition) (see the following reaction formulas (3) and (4)). By iminization, it is not taken into the yeast cells and does not inhibit fermentation.

  Moreover, although pH adjustment of an acid cooked product is performed in a process (N), it is preferable that pH is about 5-6. This is because the optimum pH for the subsequent enzyme reaction and fermentation reaction is in the neutral region. If it is used for the purpose of pH adjustment, other pH adjusters (such as sodium hydroxide) can be used, but only ammonia can reduce the fermentation inhibitor and adjust the pH of the acid cooked food at the same time. Furthermore, ammonia is an optimal compound used in the present invention because it can be a nutrient source for yeast in the fermentation process.

In this invention, content of the said fermentation inhibitory substance is reduced below the threshold value which does not cause fermentation inhibition by a process (M) and a process (N).
The content of the fermentation inhibitor that inhibits the enzyme reaction or the fermentation reaction varies depending on each reaction. It is best to remove the fermentation inhibitor to 0 ppm (detection limit). However, as the content of the fermentation inhibitor is removed, the saccharification process using the enzyme and the load of the fermentation process are reduced and the enzyme is used. Efficient saccharification process and fermentation process. However, in actuality, it is necessary to consider the cost required for the step of removing the fermentation inhibitor and the cost required for the subsequent enzymatic saccharification, fermentation and distillation steps. Moreover, it is necessary to calculate the threshold value of the content of the fermentation inhibitor that does not cause fermentation inhibition, and to consider the balance with the cost.

FIG. 3 is a graph plotting the relationship between the content of furfural, 5-HMF, and acetic acid in lignocellulosic biomass and the yield of ethanol. From FIG. 3, the threshold values for the content of furfural, 5-HMF, and acetic acid in lignocellulosic biomass are the values of the contents of furfural, 5-HMF, and acetic acid at the boundary where the yield of ethanol decreases. .
Therefore, from FIG. 3 (a), the content that does not cause fermentation inhibition of furfural is preferably 6.7 kg or less, more preferably 4.5 kg or less, relative to 1 t of dried lignocellulosic biomass. Moreover, from (b) of FIG. 3, the content that does not cause fermentation inhibition of 5-HMF is preferably 2.2 kg or less, more preferably 1.5 kg or less, relative to 1 t of dried lignocellulosic biomass. Furthermore, from FIG. 3 (c), the content that does not cause fermentation inhibition of acetic acid is preferably 44 kg or less, more preferably 30 kg or less, relative to 1 t of dried lignocellulosic biomass.

  In this invention, the reduction target value of the content of the fermentation inhibitory substance in the said process (M) is set on the basis of content of the fermentation inhibitory substance after the said process (N).

  That is, the reduction target value of the content of the fermentation inhibitor in the step of drying the acid cooked product is set based on the threshold value that does not cause fermentation inhibition of furfural, 5-HMF, and acetic acid shown in FIG. This reduction target value is expected to be reduced in the step of adding ammonia to the acid cooked product, and the furfural is preferably 7.1 kg or less with respect to 1 t of dried lignocellulosic biomass. Moreover, about 5-HMF, since it is hardly reduced by drying, the density | concentration of 5-HMF contained in an acid cooked product becomes a reduction target value as it is, and 2.9 kg or less is preferable with respect to 1 t of dried lignocellulosic biomass. . Furthermore, about acetic acid, 37 kg or less is preferable with respect to 1 t of dried lignocellulosic biomass.

Moreover, in the said process (M), since the water content of an acid cooked product has big influence on the reduction | decrease of the fermentation inhibitor which has volatility especially, and a subsequent saccharification process and a fermentation process, it needs to be adjusted. Among the fermentation inhibitory substances reduced by drying, acetic acid has a relatively high reduction target value, and reaches the reduction target value even if the water content is somewhat high. However, since furfural has a relatively low reduction target value and is greatly affected by the water content, it is preferable to set a reduction target value during the drying step of the water content based on the correlation between the content of the furfural and the water content ( FIG. 8 and FIG. 9).
Therefore, the water content in the acid cooked product after the step (M) is preferably 2.58 kg or less, more preferably 2.00 kg or less, with respect to 1 kg of the dried lignocellulosic biomass. About a lower limit, 1.00 kg or more is preferable with respect to 1 kg of dried lignocellulosic biomass from the viewpoint of the energy cost of a drying apparatus, and the moisture content required for a subsequent enzyme reaction and fermentation reaction.

  Step (B) is a saccharification step in which cellulose or hemicellulose extracted from lignocellulosic biomass is decomposed into monosaccharides and / or oligosaccharides using an enzyme. The temperature of the saccharification step is preferably 45 ° C. to 55 ° C. in order to perform the enzyme reaction.

In the present invention, the term “enzyme” means an enzyme that decomposes lignocellulosic biomass into monosaccharide units, and any enzyme that decomposes lignocellulosic biomass into monosaccharides can be used. Each activity of cellulase and hemicellulase Anything that has
Any cellulase may be used as long as it decomposes cellulose into glucose, and examples thereof include those having at least one activity of endoglucanase, cellobiohydrolase, and β-glucosidase, and an enzyme mixture having each of these activities It is preferable from the viewpoint of enzyme activity.
Similarly, the hemicellulase may be any one that decomposes hemicellulose into a monosaccharide such as xylose, and includes those having at least one activity of xylanase, xylosidase, mannanase, pectinase, galactosidase, glucuronidase, and arabinofuranosidase. An enzyme mixture having each of these activities is preferable from the viewpoint of enzyme activity.
In the present invention, the “enzyme active ingredient” means each of these saccharifying enzymes when an enzyme mixture is used, and means the saccharifying enzyme used when a single saccharifying enzyme is used.
The origin of these cellulases and hemicellulases is not limited, and cellulases and hemicellulases such as filamentous fungi, basidiomycetes, and bacteria can be used.

The step (B) is followed by a fermentation step and a distillation step, whereby a compound derived from lignocellulosic biomass is obtained.
The lignocellulosic biomass-derived compound obtained in the fermentation step means a compound produced by ingestion of monosaccharides and oligosaccharides obtained from lignocellulosic biomass by, for example, ethanol, butanol, 1, Alcohols such as 3-propanediol, 1,4-butanediol and glycerol, pyruvic acid, succinic acid, malic acid, itaconic acid, citric acid and lactic acid, organic acids such as inosine and guanosine, inosinic acid and guanylic acid And diamine compounds such as cadaverine are preferred, and ethanol is most preferred. When the compound obtained by fermentation is a monomer such as lactic acid, the polymerization process may be shifted to a polymer by polymerization. Finally, after the fermentation process or the polymerization process, a distillation process is performed as a purification process in order to improve the quality of the obtained lignocellulosic biomass-derived compound.

<Second embodiment>
FIG. 4 is a diagram showing a schematic configuration of a method for producing a lignocellulosic biomass-derived compound according to the second embodiment of the present invention.
Although it has a process (A) and a process (M) like a 1st embodiment, a process (N) and a process (B) are performed simultaneously.

In the method for producing a lignocellulosic biomass-derived compound according to the second embodiment of the present invention, step (N), which is a step of adding ammonia to reduce fermentation-inhibiting substances and adjusting the pH of the acid cooked product, and the acid cooked product Step (B), which is a saccharification step for producing a saccharified solution containing monosaccharides and / or oligosaccharides, is simultaneously performed.
When the step of adding ammonia is performed separately, the temperature of the warm acid cooked product is increased in the drying step, and when ammonia is added as it is, the ammonia volatilizes and the reaction with the fermentation inhibitor becomes insufficient. Moreover, the state in which ammonia has volatilized is not preferable in terms of the working environment. Therefore, it is necessary to cool the acid cooking after the drying step, which increases energy costs. Moreover, a kneader for adding ammonia is required. Therefore, in the saccharification step, it is possible to save at least one of cost and equipment by adding ammonia, and further reduce the fermentation inhibitor, adjust the pH of the acid cooked product, and convert the monosaccharide and / or oligo from the acid cooked product. It is possible to efficiently produce a sugar solution containing sugar.

In the same manner as in the first embodiment, the target value for reducing the content of the fermentation inhibitor in step (M) is set based on the content of the fermentation inhibitor after step (N) and step (B). That's fine.
Moreover, after a process (N) and a process (B), a fermentation process and a distillation process follow like 1st embodiment, and the compound derived from lignocellulosic biomass, such as ethanol, is obtained.

<Third embodiment>
FIG. 5 is a diagram showing a schematic configuration of a method for producing a lignocellulosic biomass-derived compound according to the third embodiment of the present invention.
Similar to the first embodiment, the process (A) and the process (M) are included.

In the third embodiment of the present invention, the step (N) includes an initial saccharification step in which (X) the acid cooked product and ammonia are added little by little to the first saccharification tank previously containing the enzyme. The step (B) includes (Y) a saccharification step in which the saccharified solution produced in the initial saccharification step is continuously added little by little to a second saccharification tank preliminarily containing an enzyme. In FIG. 5, the saccharification process is divided into two times, but there is no problem even if it is divided into three or more times.
In the initial saccharification step (X), the acid cooked product and ammonia are continuously added little by little to the first saccharification tank containing the enzyme in advance, so that the fluctuation of pH due to ammonia can be adjusted to be small, and the fermentation inhibitor Can sufficiently react with ammonia and be reduced. Furthermore, the saccharification reaction by an enzyme is accelerated | stimulated because the density | concentration in the saccharification tank of an acid cooked product is suppressed and viscosity is kept low.
Similarly, in the saccharification step (Y) subsequent to the initial saccharification step (X), the saccharification solution produced in the initial saccharification step is continuously added little by little, so that By suppressing the concentration and keeping the viscosity low, the saccharification reaction by the enzyme is promoted. At this time, the saccharified solution produced in the initial saccharification step includes monosaccharides and oligosaccharides produced by the saccharification reaction, unsaccharified hemicellulose and cellulose, and ammonium acetate produced by reacting the fermentation inhibitor with ammonia and Ammonium formate and the like are included.
In the initial saccharification step (X) and the saccharification step (Y), as a guideline for adding “a little by little”, for example, the weight in a dry state with respect to the total amount of the saccharification tank when all the lignocellulosic biomass is added The speed is such that about 0.83% of lignocellulosic biomass in terms of conversion is charged in about 1 hour using a conveyor.

Similarly to 1st embodiment, content of the said fermentation inhibitor is reduced below the threshold value which does not cause fermentation inhibition by the said process (M) and the process (X) which is a part of process (N).
Furthermore, what is necessary is just to set the reduction target value of content of the fermentation inhibitory substance in the said process (M) on the basis of content of the fermentation inhibitory substance after the process (X) which is a part of process (N).
Moreover, after a process (Y), the fermentation process and the distillation process continue like a first embodiment, and the compound derived from lignocellulosic biomass, such as ethanol, is obtained.

[Production equipment for lignocellulosic biomass-derived compounds]
<First embodiment>
The apparatus which manufactures a compound from lignocellulosic biomass which concerns on 1st embodiment of this invention is a hydrolysis processing tank which produces | generates an acid cooked product by the hydrolysis process by mixing an acid with lignocellulosic biomass and cooking. And a drying treatment tank for drying the acid cooked product to volatilize and remove the fermentation inhibitor, an ammonia addition tank for further reducing the fermentation inhibitor by adding ammonia to the dried acid cooked product, And a saccharification tank for producing a saccharified solution containing monosaccharides and / or oligosaccharides from the acid-boiled product after the addition of ammonia.

  A hydrolysis processing tank is a tank which hydrolyzes lignocellulosic biomass and produces | generates an acid cooked thing by mixing an acid with lignocellulosic biomass and cooking. The hydrolysis treatment tank includes a steaming device. Although there is no limitation in particular in a steaming apparatus, since the lignocellulosic biomass containing an acid is about pH1.0-2.0, what has acid resistance is preferable. Furthermore, the hydrolysis treatment tank may be provided with a blasting device in order to finely pulverize the lignocellulosic biomass mixed with the acid in the steaming device.

  The drying treatment tank is a tank for drying the acid cooked product generated in the hydrolysis treatment tank to volatilize and remove the fermentation inhibitor. The drying treatment tank is equipped with a drying device for drying the acid steamed product. Although it does not specifically limit about a drying apparatus, For example, flash drying, a liquid film type | mold, a jacket and a coil heating type | mold, a hot air drying apparatus etc. are mentioned. Among these, the hot air drying apparatus is particularly preferable because it directly heats the acid cooked product, and thus has high heat exchange efficiency and can suppress the cost, and the apparatus is simple.

  The ammonia addition tank is a tank in which ammonia is added to the dried acid cooked product to further reduce the fermentation inhibitor. The ammonia addition tank includes a kneader for kneading ammonia and the dried acid cooked product. Although it does not specifically limit about a kneading machine, Since it uses acid-boiled strong acid and ammonia, what has acid resistance and alkali resistance is preferable.

  A saccharification tank is a tank which manufactures the saccharified liquid containing a monosaccharide and / or an oligosaccharide from the said acid cooked product after the said ammonia addition with an enzyme. The saccharification tank is equipped with a kneader for kneading the enzyme and the acid cooked product after the addition of ammonia. The kneading machine is not particularly limited. Moreover, since it is preferable that the temperature of an enzyme reaction is 45 to 55 degreeC, it is preferable to equip the outside of a saccharification tank with temperature adjusting devices, such as a warm water circulation type jacket.

As above-mentioned, content in the said fermentation inhibitory substance is reduced below the threshold value which does not cause fermentation inhibition by the process in the said drying treatment tank and the said ammonia addition tank.
Furthermore, the reduction target value of the content of the fermentation inhibiting substance in the drying treatment tank is set based on the content of the fermentation inhibiting substance after the ammonia addition tank.
In addition, the water content of the acid cooked product needs to be adjusted because it significantly affects the reduction of the volatile fermentation inhibitor and the subsequent saccharification process and fermentation process. The water content in the acid cooked product after the drying treatment tank is preferably 2.58 kg or less, more preferably 2.00 kg or less, relative to 1 kg of the dried lignocellulosic biomass. About a lower limit, 1.00 kg or more is preferable with respect to 1 kg of dried lignocellulosic biomass from the viewpoint of the energy cost of a drying apparatus, and the moisture content required for a subsequent enzyme reaction and fermentation reaction.

  The saccharification tank is followed by a fermentor and a distillation apparatus, and a compound derived from lignocellulosic biomass such as ethanol is obtained.

<Second embodiment>
The lignocellulosic biomass-derived compound production apparatus according to the second embodiment of the present invention includes a hydrolysis treatment apparatus and a drying treatment tank as in the first embodiment, but the ammonia addition tank and the saccharification tank are combined. There are two saccharification tanks.
As described above, by simultaneously adding ammonia and saccharifying, it is possible to save at least one of cost and equipment, further reducing fermentation-inhibiting substances, adjusting the pH of the acid cooked product, It is possible to efficiently produce a sugar solution containing oligosaccharides.
As in the first embodiment, based on the content of the fermentation inhibitor after one saccharification tank in which the ammonia addition tank and the saccharification tank are combined, the target value for reducing the content of the fermentation inhibitor in the drying treatment tank is You only have to set it.
As in the first embodiment, the saccharification tank is followed by a fermenter and a distillation apparatus, and a compound derived from lignocellulosic biomass such as ethanol is obtained.

<Third embodiment>
The lignocellulosic biomass-derived compound production apparatus according to the third embodiment of the present invention has a hydrolysis treatment apparatus and a drying treatment tank as in the first embodiment, but the ammonia addition tank containing the enzyme in advance is the first. One saccharification tank is used, and the saccharification tank is a second saccharification tank.
As mentioned above, the acid cooked product and ammonia are added little by little to the first saccharification tank containing the enzyme in advance, so that the fluctuation of pH due to ammonia can be adjusted to a small extent, and the fermentation inhibitor is sufficient with ammonia. Can be reduced. Furthermore, the saccharification reaction by an enzyme is accelerated | stimulated because the density | concentration in the saccharification tank of an acid cooked product is suppressed and viscosity is kept low. Furthermore, similarly, by continuously adding the saccharified solution generated in the first saccharification tank little by little, the concentration in the second saccharification tank is suppressed, and the viscosity is kept low. Enzymatic saccharification is promoted.
Similar to the first embodiment, a target value for reducing the content of the fermentation inhibitor in the drying treatment tank may be set based on the content of the fermentation inhibitor after the first saccharification tank.
As in the first embodiment, the saccharification tank is followed by a fermenter and a distillation apparatus, and a compound derived from lignocellulosic biomass such as ethanol is obtained.

  Hereinafter, the present invention will be described in more detail with reference to specific examples. However, the present invention is not limited to the following examples.

[Example 1]
<Steaming and explosion process>
Using sugarcane bagasse (dry weight 1.5 kg) as a lignocellulosic biomass raw material, adding 1.5 mass% dilute sulfuric acid as pure sulfuric acid with respect to the dry weight of sugarcane bagasse, steaming and explosive device (manufactured by Yasima, SBK-208 type). Steaming at 190 ° C. for 1.5 minutes in a pressurized environment with saturated steam, the valve was quickly opened and crushed (explosive), and the acid steamed product was obtained in a dry weight of 1.41 kg.
<Ammonia addition process>
A dry weight of 10 g of the acid cooked product is used, put into a flask simulating a saccharification tank without performing the drying process, and immediately before the enzyme solution is added in the next saccharification process, the concentration in the saccharification tank is 10% by mass. 5 g of an aqueous ammonia solution was added. At this time, the pH was 5.5.

<Saccharification process>
0.75 g of an enzyme solution (Genencore) was added to the acid cooked product after the addition of ammonia, and the mixture was allowed to react at 50 ° C. for 48 hours to obtain 100 g of a sugar solution. At this time, the pH was 4.9.

<Fermentation process>
Yeast (“Saccharomyces cerevisiae” manufactured by Toyota Motor Corporation) was added to the sugar solution after the saccharification step, and the mixture was allowed to stand at 32 ° C. for 48 hours to obtain 101 g of a fermented product.

<Distillation process>
Using a rotary evaporator (R-205, manufactured by Shibata Kagaku), about 345 L was obtained for lignocellulosic biomass 1t (hereinafter referred to as t-dryBM) obtained by distilling the fermented product and drying ethanol.

[Example 2]
In the ammonia addition step, about 355 L / t-dryBM of ethanol was obtained in the same manner as in Example 1 except that 5 g of an aqueous ammonia solution having a concentration of 10% by mass was added and kneaded for 30 minutes before the saccharification step. The pH after the saccharification step was 4.9.

[Comparative Example 1]
In the ammonia addition step, about 60 L / t-dryBM of ethanol was obtained in the same manner as in Example 1 except that 3 g of a sodium hydroxide aqueous solution having a concentration of 17.5% by mass was added during the saccharification step. Moreover, pH after the saccharification step was 5.0.

[Test Example 1] Verification of influence on fermentation by pH adjustment method The ethanol yields of Examples 1 and 2 and Comparative Example 2 were compared with the concentration of furfural as a fermentation inhibitor (see FIG. 6). The concentration of furfural is a value measured after the saccharification step. The concentration of furfural was measured using a high performance liquid chromatograph (LC-20AD manufactured by Shimadzu Corporation).
From FIG. 6, in Example 1, the furfural was 0.93g with respect to 1L of sugar solutions.
Moreover, in Example 2, 0.89g of furfural was contained with respect to 1L of sugar solutions. Example 2 was good compared to Example 1 with a reduced amount of furfural concentration and a small ethanol yield.
On the other hand, in Comparative Example 1, 1.07 g of furfural was contained with respect to 1 L of the sugar solution.
When compared with the concentration of furfural, compared to Comparative Example 1, Example 1 reduced 13% and Example 2 reduced 16%.
Therefore, it has been clarified that ammonia is necessary for pH adjustment of acid cooked foods and reduction of fermentation inhibiting substances.

[Test Example 2] Verification of removal of fermentation inhibitor by drying and addition of ammonia In the same manner as in Example 1, steaming and blasting processes were performed to obtain an acid steamed product. Further, an acid cooked product was prepared under the following four conditions, and acetic acid, furfural and 5-HMF were measured using a high performance liquid chromatograph (LC-20AD manufactured by Shimadzu Corporation), and the results are shown in FIG. .
(I) Water was added to the acid cooked product and the water content was adjusted to 3.15 kg-water / kg-dryBM. (Ii) Water was added to the acid cooked product and the water content was 3.15 kg-water / kg-dryBM. And kneaded by adding an aqueous ammonia solution having a concentration of 14% by mass (iii) Drying in hot air at 60 ° C. to adjust the water content to 1.19 kg-water / kg-dryBM (iv) 60 Dry with hot air at ℃, adjust the water content to 1.19kg-water / kg-dryBM, and knead by adding an aqueous ammonia solution with a concentration of 14% by mass

FIG. 7 shows that the content of acetic acid is compared between (i) and (iii), which is reduced from 61 kg / t-dryBM to 34 kg / t-dryBM, and also in (ii) and (iv) containing ammonia aqueous solution. Similarly, it decreased from 55 kg / t-dryBM to 28 kg / t-dryBM. Furthermore, when (i) and (ii), (iii), and (iv), which have the same water content but differ in the presence or absence of an aqueous ammonia solution, were compared, it was confirmed that acetic acid was reduced by adding ammonia. It was done.
Moreover, when (i) and (iii) are compared about content of a furfural from FIG. 7, it has decreased from 12 kg / t-dryBM to 2.0 kg / t-dryBM, and contains aqueous ammonia solution (ii) and ( Similarly, in iv), it decreased from 8.2 kg / t-dryBM to 1.1 g / t-dryBM. Furthermore, when (i) and (ii), (iii), and (iv) are compared, but the amount of furfural is reduced by adding ammonia, although the water content is the same but the presence or absence of the aqueous ammonia solution is different. It was done.
On the other hand, FIG. 7 shows that the content of 5-HMF is slightly increased to 2.5 kg / t-dryBM, (iii) to 2.9 kg / t-dryBM, and (ii) is 2.1 kg / t. t-dryBM, (iv) was slightly reduced to 1.5 kg / t-dryBM. Furthermore, when (i) and (ii), (iii), and (iv), which have the same water content but differ in the presence or absence of an aqueous ammonia solution, are compared, the addition of ammonia reduces 5-HMF. Was confirmed.

  From the above results, it was revealed that acetic acid and furfural can be removed by drying, but 5-HMF is difficult to remove by drying. In addition, it has been clarified that any fermentation inhibitor can be removed by adding ammonia.

[Test Example 3] Verification of removal of fermentation-inhibiting substances by drying In the same manner as in Example 1, steaming and blasting steps were performed to obtain an acid steamed product. Further, the drying process was performed every 0 minutes, 10 minutes, 20 minutes, 30 minutes, 40 minutes, 50 minutes, 60 minutes and 10 minutes under the following three temperature conditions. About each acid cooked product, it dried to 105-110 degreeC using the thermostat (ADVANTEC Co., Ltd. DRS620DA) to the absolutely dry state, and the moisture content was computed by measuring the weight before and behind drying. Acetic acid, furfural, and 5-HMF were further measured using a high performance liquid chromatograph (LC-20AD manufactured by Shimadzu Corporation).
(V) Hot air temperature 60 ° C
(Vi) Hot air temperature 85 ° C
(Vii) Hot air temperature 110 ° C

(A) of FIG. 8 is the graph which showed the correlation of the water content of an acid cooked material, and a furfural content in each drying temperature and drying time. From (a) of FIG. 8, the water content at the threshold 4.5 kg / t-dryBM which does not cause fermentation inhibition of furfural is 2.0 kg / kg-dryBM, which is a reduction target value in the drying process. The water content in 1 kg / t-dryBM was confirmed to be 2.58 kg / kg-dryBM.
Furthermore, (b) of FIG. 8 is a graph showing the correlation between the moisture content of the acid cooked product and the drying time at each drying temperature and drying time. From FIG. 8B, the drying time to reach a water content of 2.58 kg / kg-dryBM is (v) 37 minutes at a hot air temperature of 60 ° C., (vi) 25 minutes at a hot air temperature of 85 ° C., (vii) 110 It was confirmed that it was 17 minutes at ° C. By increasing the temperature, the drying time can be shortened and the drying process can be performed efficiently, but it has been confirmed that the drying temperature can be appropriately changed depending on the equipment used.

FIG. 9 is a graph showing the correlation between the water content of the acid cooked product and the fermentation inhibitors acetic acid, furfural, and 5-HMF at each drying temperature and drying time. From FIG. 9, it was confirmed that 5-HMF and acetic acid were already below the reduction target value in the drying step at a high water content of 76 mass% (approximately 3.2 kg / kg-dry BM).
On the other hand, with respect to furfural, the water content at a threshold of 4.5 kg / t-dryBM that does not cause fermentation inhibition is 2.0 kg / kg-dryBM, which is a reduction target value in the drying process of 7.1 kg. The water content in / t-dryBM is 2.58 kg / kg-dryBM.
Therefore, it became clear that the water content in the reduction target value in the drying process of furfural can be set to the target reduction value in the water content in the drying process.

  From the above, in the method and apparatus for producing a lignocellulosic biomass-derived compound according to the present invention, the acid cooked product is dried, and ammonia is added before the saccharification step and / or during the saccharification step. As a result, fermentation inhibitory substances were reduced, and it became clear that lignocellulosic biomass-derived compounds could be obtained efficiently.

That is, the present invention is as follows.
(1) A method for producing a lignocellulosic biomass-derived compound,
(A) a step of producing an acid cooked product by hydrolysis by mixing an acid with lignocellulosic biomass and cooking;
(M) drying the acid-boiled product to volatilize and remove the fermentation inhibitor;
(N) adding ammonia to the dried acid cooked product, further reducing fermentation inhibiting substances, and adjusting the pH of the dried cooked product;
(B) have a, a saccharification step for producing a sugar solution containing a monosaccharide and / or oligosaccharide from the acid cooking product after the ammonia added by the enzyme,
Among the fermentation inhibiting substances, from the threshold value that does not cause fermentation inhibition of furfural, and the reduced amount of the furfural in the step (N), set a reduction target value of the content of the furfural in the step (M),
A lignocellulosic biomass-derived compound characterized in that, from the correlation between the content of the furfural and the water content of the acid cooked product, a reduction target value of the water content of the acid cooked product in the step (M) is set . Manufacturing method.
(2) The method for producing a lignocellulose-based biomass-derived compound according to (1), wherein the step (N) and the step (B) are performed simultaneously.
(3) The step (N)
(X) having an initial saccharification step in which the dried acid-boiled product and ammonia are continuously added little by little to the first saccharification tank previously containing the enzyme,
Instead of the step (B),
(Y) having a saccharification step of continuously adding the saccharified solution produced in the initial saccharification step little by little to a second saccharification tank preliminarily containing an enzyme;
(1) The manufacturing method of the lignocellulosic biomass origin compound as described in (2).
( 4 ) Any one of (1) to ( 3 ), wherein the water content in the acid cooked product after step (M) is 1.00 kg to 2.58 kg with respect to 1 kg of the dried lignocellulosic biomass. The manufacturing method of the lignocellulosic biomass origin compound as described in one.

Claims (12)

A method for producing a lignocellulosic biomass-derived compound,
(A) a step of producing an acid cooked product by hydrolysis by mixing an acid with lignocellulosic biomass and cooking;
(M) drying the acid-boiled product to volatilize and remove the fermentation inhibitor;
(N) adding ammonia to the dried acid cooked product, further reducing fermentation inhibiting substances, and adjusting the pH of the dried cooked product;
(B) a saccharification step for producing a saccharified solution containing monosaccharides and / or oligosaccharides from the acid-boiled product after addition of ammonia by the enzyme;
A process for producing a lignocellulosic biomass-derived compound, comprising:   The method for producing a lignocellulosic biomass-derived compound according to claim 1, wherein the step (N) and the step (B) are performed simultaneously. The step (N)
(X) having an initial saccharification step in which the dried acid-boiled product and ammonia are continuously added little by little to the first saccharification tank previously containing the enzyme,
The step (B)
(Y) having a saccharification step of continuously adding the saccharified solution produced in the initial saccharification step little by little to a second saccharification tank preliminarily containing an enzyme;
The manufacturing method of the lignocellulosic biomass origin compound of Claim 1 or 2.   The lignocellulosic biomass-derived compound according to any one of claims 1 to 3, wherein the content of the fermentation-inhibiting substance is reduced below a threshold value that does not cause fermentation inhibition by the step (M) and the step (N). Manufacturing method.   The ligno as described in any one of Claims 1-4 which sets the reduction target value of content of the fermentation inhibitory substance in the said process (M) on the basis of content of the fermentation inhibitory substance after the said process (N). A method for producing a cellulosic biomass-derived compound.   The water content in the acid cooked food after the step (M) is 1.00 kg or more and 2.58 kg or less with respect to 1 kg of the dried lignocellulosic biomass, ligno according to any one of claims 1 to 5. A method for producing a cellulosic biomass-derived compound. An apparatus for producing a lignocellulosic biomass-derived compound,
A hydrolysis treatment tank for producing an acid cooked product by hydrolysis by mixing an acid with lignocellulosic biomass and cooking,
A drying treatment tank for drying the acid-boiled product to volatilize and remove the fermentation inhibitor;
Adding ammonia to the dried acid cooked product, an ammonia addition tank for further reducing fermentation inhibiting substances,
A saccharification tank for producing a saccharified solution containing monosaccharides and / or oligosaccharides from the acid-boiled product after addition of ammonia by the enzyme;
An apparatus for producing a lignocellulosic biomass-derived compound, comprising:   The lignocellulosic biomass-derived compound production apparatus according to claim 7, wherein the ammonia addition tank and the saccharification tank are combined into one saccharification tank.   The lignocellulosic biomass-derived compound production apparatus according to claim 7 or 8, wherein the ammonia addition tank preliminarily containing an enzyme is a first saccharification tank, and the saccharification tank is a second saccharification tank.   The lignocellulosic biomass origin as described in any one of Claims 7-9 which reduces content of the said fermentation inhibitory substance below the threshold value which does not cause fermentation inhibition by the process in the said drying treatment tank and the said ammonia addition tank. Compound production equipment.   The lignocellulosic system according to any one of claims 7 to 10, wherein a reduction target value of the content of the fermentation inhibiting substance in the drying treatment tank is set based on the content of the fermentation inhibiting substance after the ammonia addition tank. Biomass-derived compound production equipment.   The lignocellulose as described in any one of Claims 7-11 whose water content in the acid cooked product after the said drying treatment tank is 1.00 kg or more and 2.58 kg or less with respect to 1 kg of dried lignocellulosic biomass. -Based biomass-derived compound production equipment.

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