JP2013183690A - Method of pretreating biomass containing lignocellulose - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of efficiently removing foreign matter mixed in a lignocellulose material, in a method of producing ethanol from the lignocellulose material.SOLUTION: In a method of producing ethanol from a lignocellulose material, the lignocellulose material is supplied from the material supply port of cleaning equipment, and rinse water is supplied to the material supplied to the cleaning equipment, thereby removing foreign matter mixed in the material, and then the water contained in the material cleaned in the cleaning process is dehydrated with a dehydrator.

Description

  The present invention relates to a method for efficiently removing foreign substances contained in a raw material in a continuous ethanol production method from biomass containing lignocellulose.

The technology for producing sugar from lignocellulose raw material that has been treated suitable for saccharification is the use of this sugar as a fermentation substrate for microorganisms to convert alcohol as an alternative fuel for gasoline, succinic acid and lactic acid as raw materials for plastics, etc. Since it can produce raw materials for products, it is a useful technology for the formation of a recycling society.
As a method for producing monosaccharides and small saccharides as fermentation substrates from polysaccharides in plant biomass, there is an enzymatic saccharification method in which biomass is hydrolyzed using an enzyme or a microorganism that produces the enzyme. In order to efficiently perform enzymatic saccharification, it is desirable to remove foreign substances (such as soil, sand, stone, plastic, metal, etc.) mixed in the collected biomass as much as possible. When pretreatment such as crushing or grinding is performed with foreign matter mixed in the biomass, there is a problem that a device used in the pretreatment fails or power consumption required for operation of the device increases. In addition, if foreign materials are mixed in the raw material, the saccharification and fermentation processes affect the action of enzymes and yeasts, and the efficiency of saccharification and fermentation decreases, resulting in a decrease in ethanol productivity. As a method for washing biomass, a method of washing biomass by immersing it in water has been reported (Patent Document 1). However, the method of immersing biomass in water is not desirable as a method of continuously washing because of poor working efficiency. As a method for continuously washing biomass, a method has been reported in which biomass is introduced from one side of a horizontal treated water tank, moved inside the water tank, foreign matter is allowed to settle during movement, and biomass is recovered from the opposite side of the treated water tank. (Patent Document 2). However, in the above method, since the treated water tank is horizontal and the biomass and foreign matter are contained in a large amount, the foreign matter may be stagnated in the treated water tank or if the passage of the treated water tank is blocked, the separation of the foreign matter and biomass may be deteriorated. Concerned.
Therefore, in the process of continuously producing ethanol, it is desired to develop a method for efficiently removing foreign matters mixed with the collected biomass by a simple method.

JP 2010-270320 A JP 2011-245383 A

  The subject of this invention is providing the method of removing the foreign material currently mixed with biomass efficiently by a simple method in the continuous ethanol manufacturing method from the biomass containing lignocellulose.

As a result of intensive studies to solve the above-mentioned problems, the present inventors have continuously washed and dehydrated the lignocellulose raw material mixed with foreign matters in the method of continuously producing ethanol from the lignocellulose raw material. It has been found that foreign substances can be efficiently removed from the lignocellulose raw material. Further, by using the raw material from which the foreign matter has been removed, the energy required for crushing and grinding can be reduced, and a raw material suitable for saccharification can be provided, and the following invention has been completed.

(1) In the method for producing ethanol from lignocellulose raw material, the lignocellulose raw material is supplied from the raw material supply port of the cleaning device and mixed with the raw material by supplying cleaning water to the raw material supplied to the cleaning device. And a dehydration step of dehydrating water contained in the raw material washed in the washing step by a dehydrating apparatus.

(2) The amount of water supplied to the lignocellulose raw material is 1 to 100 kg of water with respect to 1 kg (dry weight) of the raw material, and the pretreatment of the lignocellulosic raw material according to item (1) Method.

(3) The pretreatment method for a lignocellulosic material according to (1) or (2), wherein the water separated in the dehydration step is circulated and reused as supply water for a cleaning device.

According to the present invention, in the method for producing ethanol from a lignocellulose raw material, it is possible to provide a raw material suitable for saccharification by reducing the energy required for crushing and grinding by efficiently removing foreign substances contained in the raw material. Become.

It is a figure which shows the pre-processing process of the lignocellulose raw material of this invention.

  Hereinafter, the present invention will be described in more detail.

<Lignocellulose raw material>
As the lignocellulosic raw material used as a raw material in the method of the present invention, as woody material, chips or bark of papermaking trees, forest land residual materials, thinned wood, sawdust or sawdust generated from lumber mills, etc., pruning roadside trees Branches and leaves, building waste, etc. are listed. Herbaceous products include agricultural waste such as kenaf, rice straw, straw, bagasse, herbaceous energy crops Elianthus, Miscanthus and Napiergrass. In addition, as the lignocellulosic material in the present invention, paper derived from wood, waste paper, pulp, pulp sludge and the like can be used.

  Among the woody lignocellulosic raw materials, forest land remnants (including bark and branches and leaves) and bark are preferable. For example, bark of tree species such as Eucalyptus genus or Acacia genus commonly used for papermaking raw materials can be obtained in large quantities stably from lumber mills and chip factories for papermaking raw materials. Preferably used.

<Washing process>
If foreign materials are mixed in the raw material, the power consumption of the equipment used for crushing and grinding may increase, and the parts of equipment used for mechanical processing such as refiner disks (plates) used for grinding may be damaged. There is sex. In addition, problems such as troubles occurring in the manufacturing process such as clogging of piping due to foreign matters, and reduction in saccharification and fermentation efficiency occur.
In this invention, the foreign material mixed with the raw material is removed by the cleaning process.

Foreign matter (foreign matter other than lignocellulose, such as stone, dust, metal, plastic) mixed with the lignocellulosic material is removed using a cleaning device.
As illustrated in FIG. 1, the cleaning device used in the present invention has a structure in which a raw material is supplied from a raw material supply port 2 of the cleaning device M and a raw material is discharged from a raw material discharge port 3.
The raw material is supplied from the raw material supply port 2 of the cleaning device M to the cleaning device via the raw material supply line 1. The cleaning water is supplied from a cleaning water supply port 4 (also used as a foreign matter discharge port). The foreign matter separated from the raw material by the cleaning is discharged from the cleaning water supply port 4 (foreign matter discharge port) at the bottom of the cleaning apparatus M via the foreign matter discharge line 5. Foreign matter is discharged intermittently by opening and closing valves on the line.
The cleaned raw material is discharged from the raw material discharge port 3 and transferred to the cleaning drainer via the line 9. The moisture contained in the raw material is dehydrated by the dehydrating device SD and discharged from the dehydrated raw material discharge port 10. On the other hand, the dehydrated water is discharged from the dehydrating liquid discharge port 6 and sent to the washing water tank MT via the line 7 and circulated through the washing water circulation line 8 as the supply water used in the washing apparatus and reused.

  The material and shape of the cleaning apparatus used in the present invention are not particularly limited, and any apparatus that can remove foreign substances from a raw material can be used without particular limitation.

  The washing water is preferably water, but any washing solution that does not adversely affect the raw material can be used without particular limitation. The amount of water for washing the lignocellulose raw material is preferably 1 to 100 kg of water with respect to 1 kg (dry weight) of the raw material, and more preferably 10 to 60 kg of water with respect to 1 kg (dry weight) of the raw material. If the amount of cleaning water supplied to 1 kg of raw material is less than 1 kg, the cleaning effect is insufficient, and if it exceeds 100 kg, the energy required for operation of the apparatus increases, which is not preferable.

The dehydrating apparatus can be used without particular limitation as long as it is an apparatus capable of removing moisture from the raw material, such as a cleaning drainer.

By the above method, foreign substances can be efficiently removed from the raw material, and power consumption required for crushing treatment and grinding treatment can be reduced in a subsequent mechanical processing step. Since it is possible to reduce equipment damage (such as damage to the refiner disk) due to foreign matter mixed in the raw material, it is possible to suppress a reduction in ethanol productivity. Moreover, by removing the foreign matter, the reduction of saccharification efficiency due to the foreign matter is suppressed, and the sugar yield is increased. Therefore, ethanol production efficiency can be improved by introducing a washing step and a dehydration step to efficiently remove foreign matters continuously mixed in the raw material.

<Mechanical processing>
In the present invention, the lignocellulose raw material can be subjected to mechanical treatment. Examples of the mechanical treatment include arbitrary mechanical means such as crushing, cutting, and grinding, and making lignocellulose easy to be saccharified in the next chemical treatment step. Although it does not specifically limit about the mechanical apparatus to be used, For example, a uniaxial crusher, a biaxial crusher, a hammer crusher, a refiner, a kneader etc. can be used.

<Chemical treatment>
Next, the mechanically treated lignocellulose raw material is then chemically treated. As the chemical treatment, one or more alkali chemicals selected from sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium carbonate and sodium hydrogen carbonate, or one or more selected from sodium sulfite and the above alkaline chemicals are used. This is a pretreatment including a chemical treatment of immersing in a solution containing an alkaline chemical. Further, chemical treatment with an oxidizing agent such as ozone or chlorine dioxide is also possible.
The chemical treatment is preferably performed as a post-treatment of the pretreatment in combination with the mechanical treatment.

  The amount of chemicals used in the chemical treatment can be adjusted according to the situation, but lignocellulosic from the standpoint of reducing the cost of chemicals and preventing yield loss due to elution and overdegradation of cellulose. It is desirable that it is 50 mass parts or less with respect to 100 mass parts of absolutely dry materials. The immersion time and the treatment temperature of the chemical in the chemical treatment can be arbitrarily set depending on the raw materials and chemicals to be used, but a treatment time of 20 to 90 minutes and a treatment temperature of 80 to 200 ° C. are preferable. By tightening the processing conditions, elution or excessive decomposition of cellulose in the raw material may occur, so that the processing time is preferably 70 minutes or less and the processing temperature is preferably 180 ° C. or less.

As the chemical treatment, 10 to 50% by mass of sodium sulfite and 0.1 to 5% by mass of alkali as a pH adjuster can be added to the lignocellulose raw material (dry weight). When sodium sulfite is added alone to the lignocellulose in the above-mentioned addition amount and heat-treated, an organic acid such as acetic acid is generated during hydrolysis, so that the pH is lowered and the hydrolyzed solution becomes acidic. When hydrolysis is continued under acidic conditions, the problem arises that xylose produced by hydrolysis is converted to furfural. Since furfural is an inhibitor of ethanol fermentation, it is desirable not to produce it as much as possible. Moreover, since the yield of xylose which is a fermentation substrate falls, ethanol production efficiency falls as a result. In the present invention, by adding sodium sulfite and an alkali as a pH adjuster to the lignocellulose raw material in the above-described amount and heat-treating, the pH during hydrolysis is maintained from neutral to weakly alkaline. Production and reduction in xylose yield can be suppressed. Moreover, since the pH of the aqueous solution containing lignocellulose after heat treatment (after hydrolysis) is 4.0 to 7.0 (neutral to weakly alkaline), the waste liquid or hydrolyzate after the hydrolysis treatment is neutralized. There is a merit that the amount of chemicals used for the reduction can be reduced.

  Examples of the alkali used as the pH adjuster include sodium hydroxide, potassium hydroxide, sodium carbonate and the like, but are not particularly limited to these chemicals.

The heat treatment temperature in the case where the heat treatment is performed by adding 10 to 50% by weight of sodium sulfite and 0.1 to 5% by weight of alkali as a pH adjuster with respect to the lignocellulose raw material (dry weight) is 80 -200 degreeC is preferable and 120-180 degreeC is more preferable. Moreover, although heat processing time can be performed in 10 to 300 minutes, 30 to 120 minutes are preferable. By tightening the processing conditions, elution or excessive decomposition of cellulose in the raw material may occur, so that the processing temperature is preferably 180 ° C. or lower and the processing time is 120 minutes or shorter.

(Grinding treatment)
In this invention, it is preferable to grind the lignocellulose raw material obtained by the said chemical process in the range of 0.1-2.0 mm of the clearance of the refiner disc (plate), 0.1-1.0 mm A range is further preferred. As a refiner to be used, a single disk refiner, a double disk refiner, or the like can be used, and any refiner that can set the clearance of the opposing disk within a range of 0.1 to 2.0 mm can be used without particular limitation. it can. When the disc clearance exceeds 2.0 mm, the sugar yield obtained by saccharification or concurrent saccharification and fermentation is not preferable. On the other hand, if the disc clearance is less than 0.1 mm, the yield of the hydrolyzate (solid content) after grinding with the refiner decreases, and the electricity consumption required for the operation of the refiner increases. .
The material of the refiner disk (plate), the disk mold, the disk surface blade mold, the direction of the blade with respect to the disk surface, etc. should be used without any limitation as long as the material and shape are effective. Can do.

  The lignocellulosic raw material that has been subjected to the above grinding treatment is subjected to solid-liquid separation into an aqueous solution and a solid content, and the solid content is used as a raw material for saccharification or concurrent saccharification and fermentation. As a method for solid-liquid separation, for example, an aqueous solution and a solid content can be separated using a screw press or the like, but any apparatus that can separate into an aqueous solution and a solid content can be used without limitation.

It is preferable to perform sterilization treatment before saccharification or parallel saccharification fermentation using the raw material after the solid separation. When miscellaneous bacteria are mixed in the lignocellulosic biomass raw material, there is a problem that the miscellaneous bacteria consume sugar when the enzyme is saccharified and the yield of the product decreases.
The sterilization treatment may be a method in which the raw material is exposed to a pH at which bacteria are difficult to grow, such as acid or alkali, but may be a method in which the raw material is treated at a high temperature, or a combination of both. About the raw material after an acid and an alkali treatment, it is preferable to use as a raw material, after adjusting to neutrality vicinity or pH suitable for a saccharification and / or saccharification fermentation process. In addition, even when pasteurized at a high temperature, it is preferably used as a raw material after the temperature is lowered to room temperature or a temperature suitable for the saccharification and fermentation process. Thus, by feeding out the raw material after adjusting the temperature and pH, it is possible to prevent the enzyme from being exposed to the outside of the preferred pH and the preferred temperature and being deactivated.

  The pretreated lignocellulose raw material is supplied to the saccharification process or the concurrent saccharification and fermentation process.

<Saccharification process>
The lignocellulosic raw material that has been subjected to pretreatment suitable for the enzymatic saccharification reaction is mixed with an appropriate amount of water and an enzyme to form a raw material suspension, which is supplied to the saccharification step. Lignocellulose-based raw materials are saccharified (cellulose → glucose, hemicellulose → glucose, xylose) by enzymes (cellulase, hemicellulase).

<Concurrent saccharification and fermentation process>
The lignocellulosic raw material that has been pretreated suitable for the enzymatic saccharification reaction is mixed with an appropriate amount of water and enzyme to form a raw material suspension, and further mixed with microorganisms such as yeast and supplied to the parallel saccharification and fermentation process. The The lignocellulosic material is saccharified by an enzyme, and the produced sugar is fermented to ethanol by yeast.

It is preferable that the suspension concentration of the lignocellulosic material used in the saccharification process or the concurrent saccharification and fermentation process is 1 to 30% by mass. If it is less than 1% by mass, there is a problem in that the concentration of the product is ultimately too low and the cost for concentrating the product becomes high. Moreover, as the concentration exceeds 30% by mass, it becomes difficult to stir the raw materials, resulting in a problem that productivity is lowered.

Cellulolytic enzymes used in parallel saccharification and fermentation are enzymes collectively called cellulases having cellobiohydrolase activity, endoglucanase activity, and betaglucosidase activity.
Each cellulolytic enzyme may be added with an appropriate amount of an enzyme having the respective activity. However, commercially available cellulase preparations have the above-mentioned various cellulase activities and also have hemicellulase activity. Since many products are available, a commercially available cellulase preparation may be used.

Commercial cellulase preparations include the genus Trichoderma, the genus Acremonium, the genus Aspergillus, the genus Phanerochaete, the genus Trametes, the genus Humicola, and the like. There are cellulase formulations derived from Commercially available products of such cellulase preparations are all trade names, for example, cellulosin T2 (manufactured by HIPI), mecerase (manufactured by Meiji Seika Co., Ltd.), Novozyme 188 (manufactured by Novozyme), multifect CX10L (manufactured by Genencor) ), GC220 (manufactured by Genencor).
0.5-100 mass parts is preferable and, as for the usage-amount of the cellulase formulation with respect to 100 mass parts of raw material solid content, 1-50 mass parts is especially preferable.

The pH in the saccharification process or the concurrent saccharification and fermentation process is preferably maintained in the range of 3.5 to 10.0, more preferably in the range of 4.0 to 7.5.

  The temperature of the saccharification step or the concurrent saccharification and fermentation step is not particularly limited as long as it is within the optimum temperature range of the enzyme, preferably 25 to 50 ° C, and more preferably 30 to 40 ° C. The reaction is preferably continuous, but may be semi-batch or batch. The reaction time varies depending on the enzyme concentration, but in the case of a batch system, it is 10 to 240 hours, more preferably 15 to 160 hours. Also in the case of a continuous type, the average residence time is 10 to 150 hours, more preferably 15 to 100 hours.

  As the microorganism used for fermentation, yeast or the like is used, and a medium or the like may be added simultaneously. As yeast, Saccharomyces cerevisiae (Saccharomyces cerevisiae) etc. can be used. Moreover, the genetically modified yeast produced using the genetic recombination technique can be used. As the genetically modified yeast, yeast capable of simultaneously fermenting hexose and pentose can be used without particular limitation. Yeast may be added at the same time as the medium.

  Moreover, the microorganisms may be immobilized. By immobilizing microorganisms, it is possible to omit the process of sending the microorganisms together with the liquid and recovering them again in the next process, or at least reduce the burden on the recovery process and reduce the risk of losing microorganisms. You can also In addition, although there is no merit as to immobilize the microorganism, it is possible to facilitate the recovery of the microorganism by selecting an aggregating microorganism.

  In the present invention, a water-soluble salt can be added as an electrolyte in the enzymatic saccharification treatment step. In the enzymatic saccharification treatment step, it is preferable to add an electrolyte to the raw material suspension to maintain the electric conductivity of the raw material suspension in the range of 5 to 25 mS / cm. By maintaining the electrical conductivity in the range of 5 to 25 mS / cm, the adsorption of the enzyme to the unreacted components and reaction residues of the lignocellulose raw material is suppressed, so the enzyme circulation rate in the enzymatic saccharification treatment process is long Over high levels. In the enzymatic saccharification treatment step, the electrolyte can be added without limitation in any step as long as it is an operation that can add an electrolyte. It is desirable to add it in the primary saccharification and fermentation process because the operation is easy.

  As the water-soluble salt, salts selected from alkali metal salts and alkaline earth metal salts are preferable. Alkali metal salts and alkaline earth metal salts include alkali metal and alkaline earth metal halides, sulfates, sulfites, thiosulfates, carbonates, bicarbonates, phosphates, dihydrogen phosphates, Examples thereof include water-soluble salts selected from the group consisting of hydrogen phosphate di-salt, acetate and citrate.

The culture solution that has exited the saccharification step or the concurrent saccharification and fermentation step is transferred to a solid-liquid separation step and separated into a liquid (filtrate) and a solid (residue). As an apparatus for performing solid-liquid separation, a screw press, a screen, a filter press, a belt press, a rotary press, or the like can be used. As the screen, a vibrating screen to which a vibrating device is added can be used.
The recovered solid (residue) can be transferred to a saccharification process or a concurrent saccharification and fermentation process and used as a raw material for saccharification and fermentation.
The liquid component (filtrate) separated in the solid-liquid separation step is transferred to the distillation step.

<Distillation process>
In the distillation step, ethanol is distilled and separated as a fermentation product by a vacuum distillation apparatus. Since the fermentation product can be separated at a low temperature under reduced pressure, inactivation of the enzyme can be prevented. As the vacuum distillation apparatus, a rotary evaporator, a flash evaporator, or the like can be used.
The distillation temperature is preferably 25 to 60 ° C. If it is lower than 25 ° C., it takes time to distill the product, and the productivity is lowered. On the other hand, when the temperature is higher than 60 ° C., the enzyme is heat-denatured and deactivated, and the amount of newly added enzyme increases, resulting in poor economic efficiency.
The concentration of the fermentation product remaining in the distillation residue fraction after distillation is preferably 0.1% by mass or less. By setting it as such a density | concentration, the amount of fermentation products discharged | emitted with a solid substance in a subsequent solid-liquid separation process can be reduced, and a yield can be improved.

<Centrifuge separation>
The distillation residue is transferred to a centrifugal separation step, and the remaining residue is removed by centrifugation. Then, the liquid fraction is circulated to the parallel saccharification and fermentation step or the secondary parallel saccharification and fermentation step (the primary parallel saccharification and fermentation step). Second saccharification and fermentation step different from the fermentation step). In the secondary concurrent saccharification and fermentation step, a new lignocellulose raw material can be added to cause saccharification and fermentation, and fermentation for the purpose of fermentation of pentoses such as xylose can be performed. The liquid fraction after centrifugation contains an enzyme and is reused in the parallel saccharification and fermentation process or the secondary saccharification and fermentation process. On the other hand, the residue after centrifugation contains enzymes, lignin, and yeast. Lignin can be recovered as a combustion raw material and used as energy, or lignin can be recovered and used effectively. In addition, yeast can be separated from the residue and reused in the saccharification and fermentation process.

EXAMPLES Next, although an Example is shown and this invention is demonstrated further in detail, this invention is not limited by these Examples.

[Experiment 1]
[Preprocessing]
Chip-like eucalyptus globulas forest residue (70% bark, 30% branches and leaves) is continuously supplied at a feed rate of 10 kg (dry weight) / min from the feed port 2 of the cleaning device shown in FIG. For 1 kg (dry weight), 100 kg of water was supplied from a cleaning water supply port (foreign matter discharge port) 4 at the bottom of the cleaning device. The foreign matter separated from the raw material by the cleaning was discharged from the cleaning water supply port 4 (foreign matter discharge port) of the cleaning device M through the foreign matter discharge line 5 by opening the valve on the line. On the other hand, after the washed raw material was discharged from the raw material discharge port 3, it was transferred to the cleaning drainer SD via the raw material transfer line 9, and the water contained in the raw material was dehydrated by the cleaning drainer. The washing water separated from the raw material is discharged from the dehydrating liquid discharge port 6, transferred to the washing water tank MT via the dehydrating liquid discharge line 7, and the washing water accumulated in the washing water tank MT passes through the washing water circulation line 8. The water was reused as cleaning water for supplying water to the cleaning device via. The weight (dry weight) of the foreign material separated from 1 kg (dry weight) of the raw material was measured.
Next, the raw material discharged from the cleaning drainer SD was crushed by a uniaxial crusher (manufactured by Saiho Kiko Co., Ltd., SC-15) equipped with a 20 mm round hole screen and used as a raw material. Electric power required for the uniaxial crushing process was measured using a power accumulator.
After adding 200 g of 97% sodium sulfite and 10 g of sodium hydroxide to 1 kg (absolute dry weight) of the raw material, water was added to adjust the volume of the aqueous solution to 6 L. The raw material suspension was mixed and then heated at 170 ° C. for 1 hour. The raw material suspension after the heat treatment was ground with a refiner (manufactured by Kumagai Riki Kogyo Co., Ltd., KRK high concentration disk refiner) with the disc clearance set to 1.0 mm. The power required for the refiner's grinding treatment was measured using a power accumulator.
Next, the ground material suspension was subjected to solid-liquid separation with a screw press (manufactured by Togoku Industry Co., Ltd., SHX-200X1500L), and a saccharification test was performed using the solid content as a raw material.
[Saccharification test (in vitro test)]
The saccharification test was carried out in a test tube using the solid content obtained above as a raw material by the following method.
A 300 ml Erlenmeyer flask (sterilized) was added so that the final concentration of the raw material was 2.5% by mass. Next, 2.5 ml of commercially available cellulase (Accelerase DUET, Genencor) was added, and the final volume was made up to 100 ml with distilled water. This mixed solution was cultured (saccharified) at 37 ° C. for 24 hours. The culture solution after the culture was centrifuged (5000 rpm, 20 minutes), and the total sugar concentration of the supernatant was measured. From the obtained data, the sugar yield (the total amount of sugar obtained / the amount of carbohydrate contained in the raw material × 100) was calculated. The results are shown in Table 1.

[Experiment 2]
In Experimental Example 1, all tests were performed in the same manner as in Experimental Example 1, except that 60 kg of water was supplied to 1 kg (dry weight) of the raw material with a cleaning device. The results are shown in Table 1.

[Experiment 3]
In Experimental Example 1, all tests were performed in the same manner as in Experimental Example 1 except that 30 kg of water was supplied to 1 kg (dry weight) of the raw material with a cleaning device. The results are shown in Table 1.

[Experimental Example 4]
In Experimental Example 1, all tests were performed in the same manner as in Experimental Example 1, except that 10 kg of water was supplied to 1 kg (dry weight) of the raw material with a cleaning device. The results are shown in Table 1.

[Experimental Example 5]
In Experimental Example 1, all tests were performed in the same manner as in Experimental Example 1 except that 5 kg of water was supplied to 1 kg (dry weight) of the raw material with a cleaning device. The results are shown in Table 1.

[Experimental Example 6]
In Experimental Example 1, all tests were performed in the same manner as in Experimental Example 1 except that 1 kg of water was supplied to 1 kg (dry weight) of the raw material with a cleaning device. The results are shown in Table 1.

[Experimental Example 7]
In Experimental Example 1, a test in which the washing step and the dehydrating step were omitted was performed. All other operations were tested in the same manner as in Experimental Example 1. Experimental example 7 was used as a comparative example.

As shown in Table 1, in the test (Experimental Examples 1 to 6) in which 1 to 100 kg of water was supplied to 1 kg (dry weight) of the raw material with a cleaning device and the raw material was washed and dehydrated, the washing step and the dehydrating step were omitted. Compared with the test (Experimental Example 7), the power consumption required for the operation of the uniaxial crusher and the refiner was low, and the sugar yield from the raw material obtained by the pretreatment was high. Moreover, in Experimental Examples 1-6, the weight of the foreign material isolate | separated increased, so that the supply amount of the water with respect to a raw material was large.
From the above results, foreign substances (soil, sand, plastic, metal, stones, etc.) contained in the forest remnant by supplying 1 to 100 kg of water to 1 kg (dry weight) of the raw material and cleaning it in the cleaning device. As a result of efficient removal, the power consumption of the uniaxial crusher and refiner is reduced, and it is estimated that the sugar yield from the raw material obtained in the pretreatment is improved. Further, in the test (Experimental Example 7) in which cleaning and dehydration were omitted, the refiner disk was damaged, but in the tests in which cleaning and dehydration were performed, no disk damage was observed in any of the tests. By removing the foreign matters by the washing process and the dehydration process in the ethanol production process, continuous operation becomes possible and efficient ethanol production becomes possible.

[Experimental Example 8]
In Experimental Example 1, 150 g of sodium hydroxide was added to 1 kg (absolute dry weight) of the raw material as a chemical treatment, and the test was performed in the same manner as in Experimental Example 1. All other operations were tested in the same manner as in Experimental Example 1. The results are shown in Table 2.

[Experimental Example 9]
In Experimental Example 1, 150 g of calcium hydroxide was added to 1 kg (absolute dry weight) of the raw material as a chemical treatment, and the test was performed in the same manner as in Experimental Example 1. All other operations were tested in the same manner as in Experimental Example 1. The results are shown in Table 2.

As shown in Table 2, in a test in which 100 kg of water was supplied to 1 kg (dry weight) of raw material in a cleaning apparatus and the raw material was washed and dehydrated, sodium hydroxide (Experimental Example 8) or calcium hydroxide (Experimental Example) Even when the chemical treatment was performed in 9), the power consumption required for the operation of the uniaxial crusher and the refiner was lower than in the test (Experimental Example 7) in which the washing step and the dehydration step were omitted, and the pretreatment was obtained. The sugar yield from the raw material was high. Also in Examples 8 and 9, no damage to the refiner disk was observed.

According to the present invention, in a continuous ethanol production method from a lignocellulose raw material, foreign matters mixed in the lignocellulose raw material can be efficiently removed. Moreover, the energy required for mechanical processing can be reduced by using the raw material from which the foreign substances have been removed, and it becomes possible to efficiently produce a sugar solution that becomes a raw material for ethanol fermentation.

1: Raw material supply line 2: Raw material supply port 3: Raw material discharge port 4: Washing water supply port (foreign matter discharge port)
5: Foreign matter line 6: Dehydration liquid discharge port 7: Dehydration liquid discharge line 8: Cleaning liquid circulation line 9: Raw material transfer line 10: Dehydration raw material discharge port M: Cleaning device MT: Cleaning water tank SD: Cleaning drainer I: Crushing processing device CO: Heat treatment device R: Grinding treatment device S: Solid-liquid separation device

Claims (3)

In the method for producing ethanol from the lignocellulose raw material, the lignocellulose raw material is supplied from the raw material supply port of the cleaning device, and the foreign matter mixed in the raw material is supplied to the raw material supplied to the cleaning device by supplying cleaning water. A method for pretreatment of a lignocellulosic raw material, comprising: a cleaning step to remove, and a dehydrating step of dehydrating water contained in the raw material cleaned in the cleaning step with a dehydrator. The amount of water supplied to the lignocellulose raw material is 1 to 100 kg of water with respect to 1 kg (dry weight) of the raw material. The method for pretreatment of a lignocellulosic material according to claim 1 or 2, wherein the water separated in the dehydration step is circulated and reused as supply water for a cleaning device.

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