JP2012010684A - Pretreatment apparatus for saccharification of lignocellulose-based biomass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pretreatment apparatus for saccharification which can obtain a treated material from a lignocellulose-based biomass as a substrate before saccharification without heating, and can reduce a cost.SOLUTION: The pretreatment apparatus 1 for saccharification includes: a treatment device 2 for obtaining a treated material before saccharification by treating obtained substrate mixture and dissociating lignin included in the base or swelling the substrate; and an ammonia separator 3 for separating ammonia from the treated material before saccharification. The treatment device 2 includes: a treatment tank 21; a substrate supplier 22; an ammonia water supplier 23; a mixer for obtaining the substrate mixture by stirring the substrate and the ammonia water to give the substrate a shearing force and an impact force and mixing the ammonia water and the substrate; a discharger 24 discharging the substrate mixture; and a storage tool 25 for dissociating the lignin included in the substrate in a non-heated state when the substrate mixture is stored for a predetermined time, or swelling the substrate.

Description

  The present invention relates to a saccharification pretreatment apparatus for lignocellulosic biomass.

  Conventionally, a method of producing ethanol by saccharifying lignocellulosic biomass such as rice straw with a saccharifying enzyme produced by a microorganism and fermenting the obtained sugar as a substrate is known. Here, the lignocellulosic biomass has a structure in which lignin is firmly bound to cellulose or hemicellulose. Therefore, the saccharification pretreatment product obtained by pretreating the lignocellulosic biomass, dissociating lignin contained in the lignocellulosic biomass, or swelling the lignocellulosic biomass is used.

  In the present application, the term “dissociation” means that at least a part of the bond between cellulose or hemicellulose and lignin is broken. Further, the term “swelling” means that the crystalline cellulose expands by forming voids in the cellulose or hemicellulose constituting the crystalline cellulose by the intrusion of the liquid, or forming voids inside the cellulose fiber. .

  In the conventional method for producing ethanol, since the saccharifying enzyme is expensive, the amount of the saccharifying enzyme used is reduced by reducing the concentration of the substrate contained in the pre-saccharification product. However, when the substrate contained in the saccharification pretreatment product has a low concentration, the saccharification solution obtained from such a saccharification pretreatment product also has a low concentration, and as a result, the ethanol obtained by fermenting the saccharification solution has a low concentration It becomes. As a result, when the obtained ethanol is distilled to concentrate, there is a problem that time and heat energy required for the distillation increase.

  In order to solve the above problem, it is conceivable to obtain a high concentration of ethanol by increasing the amount of the saccharification enzyme while increasing the concentration of the substrate contained in the pre-saccharification product. In this case, since the amount of the expensive saccharifying enzyme used increases and costs increase, it is necessary to reduce the overall cost of the ethanol production method.

  As one measure for reducing the cost in the ethanol production method, it is conceivable to improve the efficiency of pretreatment for saccharification of the lignocellulosic biomass.

  As a method for pretreatment of lignocellulosic biomass saccharification, for example, a method is known in which lignocellulosic biomass is mixed with liquid pure ammonia, heated and pressurized, and then the pressure is rapidly reduced. If it does in this way, when the vaporized ammonia gas is rapidly expanded, the lignocellulosic biomass is also expanded, and lignin is physically removed from the lignocellulosic biomass (see Patent Document 1).

  However, in order to use pure ammonia, a special device such as a pressure vessel for storage thereof is required. Therefore, it has been studied to use ammonia water in which pure ammonia is used as an aqueous solution.

  As a method of using the ammonia water, a method is known in which the lignocellulosic biomass is brought into contact with ozone and then immersed in ammonia water (see Patent Document 2). However, in this case, an apparatus for bringing the lignocellulosic biomass into contact with ozone is necessary, and a process for that purpose is added, so that the cost cannot always be reduced.

  Moreover, the method of heating the mixture obtained by mixing the said lignocellulosic biomass and ammonia water is known (refer patent document 3). According to the method described in Patent Document 3, the lignocellulosic biomass is dispersed in ammonia water having a concentration of 0.8 to 15% by weight and heated to dissociate lignin from the lignocellulosic biomass, or the It is said that lignocellulosic biomass can be swollen.

JP 2005-232453 A JP 57-5697 A Special table 2008-535524 gazette

  However, in order to carry out the method described in Patent Document 3, an apparatus including heating means for dissociating lignin from the lignocellulosic biomass or supplying thermal energy for swelling the lignocellulosic biomass is required. There is an inconvenience.

  Therefore, the present invention eliminates such inconvenience, and can dissociate lignin from the lignocellulosic biomass or swell the lignocellulosic biomass without supplying thermal energy, and can be used for the saccharification pretreatment. It aims at providing the saccharification pre-processing apparatus of lignocellulosic biomass which can reduce the required cost.

  In order to achieve such an object, the lignocellulosic biomass saccharification pretreatment apparatus of the present invention adds ammonia water to lignocellulosic biomass as a substrate and treats the resulting substrate mixture to be contained in the substrate. In a pretreatment for saccharification of lignocellulosic biomass, comprising a treatment means for dissociating lignin to be obtained or swelling the substrate to obtain a pre-saccharification product, and an ammonia separation means for separating ammonia from the pre-saccharification product. The treatment means includes a treatment tank, a substrate supply means for continuously supplying the substrate to the treatment tank, an ammonia water supply means for continuously supplying the ammonia water to the treatment tank, and a supply to the treatment tank. Mixing the substrate and the aqueous ammonia to impart shearing force and impact force to the substrate and mixing the aqueous ammonia and the substrate to mix the substrate Mixing means for obtaining the substrate mixture, discharging means for continuously discharging the substrate mixture from the treatment tank, and storing the substrate mixture discharged by the discharging means for a predetermined time, and in a non-heated state during storage And a storage means for swelling the substrate.

  According to the lignocellulosic biomass saccharification pretreatment apparatus of the present invention (hereinafter sometimes abbreviated as saccharification pretreatment apparatus), first, the substrate is supplied from the substrate supply means and the ammonia water supply means, respectively. Lignocellulosic biomass as a substrate and ammonia water are continuously supplied.

  Here, lignocellulosic biomass as the substrate is difficult to be uniformly impregnated with the ammonia water simply by mixing with the ammonia water, and heating to dissociate lignin by causing ammonia to act on such a substrate. Need.

  On the other hand, in the saccharification pretreatment device of the present invention, the substrate and the ammonia water are continuously supplied to the treatment tank, and the ammonia water and the substrate are stirred by the mixing means. Mixed. At this time, by applying a shearing force and an impact force to the substrate, a substrate mixture in which the ammonia water is uniformly impregnated into the substrate can be obtained.

  In the saccharification pretreatment device of the present invention, next, the substrate mixture obtained by the mixing means is continuously discharged from the processing tank by the discharge means and stored in the storage means.

  The substrate in the substrate mixture supplied to the storage means is uniformly impregnated with the ammonia water. Thus, in the substrate, while being stored in the storage means, the reaction of dissociating lignin from the substrate with ammonia or swelling the substrate proceeds without heating.

  Therefore, in the saccharification pretreatment device of the present invention, the glycation pretreatment product in which the substrate mixture is stored in the storage means for a predetermined time to dissociate lignin from the substrate without being heated or the substrate is swollen. Can be obtained, and the cost required for the pre-saccharification treatment can be reduced.

  In the saccharification pretreatment apparatus of the present invention, the ammonia separation means then separates ammonia from the saccharification pretreatment product, whereby a saccharification pretreatment product from which ammonia has been separated can be obtained.

  In the saccharification pretreatment apparatus of the present invention, since the substrate mixture obtained in the treatment tank is a wet powder, when the treatment tank and the storage means are connected by a pipe or the like, the moisture is contained in the pipe. There is a concern that the powder may cause a bridging phenomenon to block the pipe.

  Therefore, in the pre-saccharification pretreatment apparatus of the present invention, it is preferable that the storage means is disposed immediately below the treatment tank and connected to the treatment tank via the discharge means. As a result, in the saccharification pretreatment apparatus of the present invention, the substrate mixture that is the wet powder can be supplied from the treatment tank to the storage means without causing a bridging phenomenon.

  In the saccharification pretreatment device of the present invention, the ammonia water supply means supplies ammonia water having a concentration in the range of 20 to 30% by mass, and the ammonia water is supplied to the substrate supplied by the substrate supply means. The mass ratio is preferably in the range of 1: 0.7 to 1: 1.3. By doing so, in the mixing means, the substrate can be more uniformly impregnated with the ammonia water, and lignin can be dissociated from the substrate or the substrate can be more easily swollen.

  Here, when the concentration of the ammonia water is less than 20% by mass, dissociation of lignin from the substrate or swelling of the substrate may be insufficient. On the other hand, even when the concentration of the ammonia water exceeds 30% by mass, no further effect can be obtained with respect to dissociation of lignin from the substrate or swelling of the substrate.

  Further, when the ammonia water added to 1 part by mass of the substrate is less than 0.7 parts by mass, the ammonia water becomes too small to uniformly impregnate the substrate with the ammonia water. Sometimes. As a result, dissociation of lignin from the substrate or swelling of the substrate may be insufficient.

  On the other hand, even if the ammonia water added to 1 part by mass of the substrate exceeds 1.3 parts by mass, no further effect can be obtained with respect to dissociation of lignin from the substrate or swelling of the substrate. .

  In the storage means, when the substrate mixture is supplied from the discharge means of the processing tank, air or ammonia gas is mixed, and the space inside the storage means can be effectively used for storing the substrate mixture. There is concern that it will not be possible. Therefore, in the pre-saccharification pretreatment apparatus of the present invention, it is preferable that the storage unit includes an exhaust port for discharging ammonia gas and air at an upper part thereof. By providing the exhaust port, the storage means can discharge the ammonia gas and air to the outside, and the internal space can be effectively used for storing the substrate mixture.

The block diagram which shows one structural example of the saccharification pre-processing apparatus of the lignocellulosic biomass of this invention. Explanatory sectional drawing which shows an example of the mixing means used for the saccharification pre-processing apparatus of lignocellulosic biomass shown in FIG.

  Next, embodiments of the present invention will be described in more detail with reference to the accompanying drawings.

  As shown in FIG. 1, the lignocellulosic biomass saccharification pretreatment apparatus 1 of this embodiment includes a treatment means 2, an ammonia separation means 3, and a transfer means 4. The treatment means 2 mixes lignocellulosic biomass as a substrate and water to form a substrate mixed solution, and dissociates lignin from the substrate in the substrate mixed solution or swells the substrate before saccharification. This is an apparatus for obtaining a processed product. The ammonia separation means 3 is a device for separating ammonia from the pre-saccharification product. The transfer means 4 is a device for transferring the pre-saccharification product from which ammonia has been separated to a subsequent enzyme saccharification step.

  In this embodiment, for example, rice straw can be used as the lignocellulosic biomass as the substrate.

  The processing unit 2 includes a processing tank 21, and the processing tank 21 includes a substrate supply unit 22 that continuously supplies the substrate and an ammonia water supply unit 23 that continuously supplies ammonia water. Further, the treatment tank 21 is provided with a mixing means (not shown) for stirring the substrate and the aqueous ammonia to impart shearing force and impact force to the substrate and mixing the aqueous ammonia and the substrate. . Furthermore, the treatment tank 21 is provided with a discharge means 24 for continuously discharging a substrate mixture obtained by mixing ammonia water and the substrate.

  Further, the processing means 2 includes a silo 25 as a storage means for storing the substrate mixture discharged from the processing tank 21 by the discharge means 24. The silo 25 is disposed directly below the processing tank 21. The lower end of the discharge means 24 is inserted into a silo 25, and the silo 25 is connected to the processing tank 21 via the discharge means 24.

  The silo 25 obtains a saccharification pretreatment product by dissociating lignin from the substrate without heating or swelling the substrate while storing the substrate mixture for a predetermined time. The silo 25 is provided with an exhaust port 26 at the top thereof. The exhaust port 26 has a function of discharging ammonia gas and air mixed when the substrate mixture is discharged from the processing tank 21 by the discharge unit 24 to the outside.

  The ammonia separation means 3 includes a powder feeder 3a that supplies the pre-saccharification product obtained in the silo 25 to the inside. The powder feeder 3 a is disposed directly below the silo 25 and is directly connected to the silo 25.

  Next, the operation of the pretreatment device 1 of this embodiment will be described.

  In the pretreatment apparatus 1, first, in the treatment means 2, the substrate is continuously supplied from the substrate supply means 22 to the treatment tank 21, and ammonia water is continuously supplied from the ammonia water supply means 23 to the treatment tank 21. . For example, rice straw can be used as the substrate. The rice straw is pulverized to a length of about 3 mm by a cutter mill (not shown), for example.

  Moreover, as this ammonia water, what is provided with the density | concentration of the range of 20-30 mass%, for example, the density | concentration of 25 mass% is used in this embodiment. When supplying the ammonia water, the ammonia water supply means 23 is in the range of 0.7 to 1.3 parts by mass of the ammonia water with respect to 1 part by mass of the substrate supplied by the substrate supply means 22. Preferably, 1 part by mass is supplied.

  The substrate and the ammonia water supplied as described above are stirred in the treatment tank 21, whereby the ammonia water and the substrate are mixed to form a substrate mixture. At this time, the substrate is given an impact force due to a collision with the ammonia water supplied simultaneously, a collision between the substrates, a collision between the substrate and the treatment tank 21, and a shearing force due to the stirring. The As a result, the ammonia water is uniformly impregnated in the substrate.

  Next, the substrate mixture is continuously discharged from the treatment tank 21 by the discharge means 24 and supplied to the silo 25. At this time, although the substrate mixture is a wet powder, the silo 25 is disposed immediately below the treatment tank 21, and the lower end of the discharge means 24 is inserted into the silo 25. Accordingly, the substrate mixture is supplied to the silo 25 without causing the bridging phenomenon to block the discharge means 24.

  At this time, ammonia gas and air are mixed in the silo 25 together with the substrate mixture. However, since the ammonia gas and air are discharged to the outside of the silo 25 from the exhaust port 26 provided in the upper part of the silo 25, the ammonia gas and air hinder the storage of the substrate mixture in the silo 25. There is no.

  In the present embodiment, for example, a mixer 31 (manufactured by Taihei Koki Co., Ltd., trade name: spiral pin mixer (W type)) having the configuration shown in FIG. The mixer 31 includes a housing 34 including a flat upper lid 32 and an inverted conical side wall 33 continuous downward from the outer peripheral edge of the upper lid 32, and a powder inlet 35 and a liquid inlet 36 at the center of the upper lid 32. And concentrically. The housing 34 includes a rotatable mixing rotor 37 inside and a discharge port 38 that opens to a part below the side wall 33.

  The mixing rotor 37 includes a horizontal surface 39 that faces the upper lid 32 with a space therebetween, and a slope 40 that extends downward from the outer peripheral edge of the horizontal surface 39 and faces the side wall 33 with a space therebetween. . A plurality of primary dispersion pins 41 are spirally disposed on the horizontal surface 39, and a plurality of secondary dispersion pins 42 are disposed on the inclined surface 40.

  In the mixer 31, the powder inlet 35 corresponds to the substrate supply unit 22, and the liquid inlet 36 corresponds to the ammonia water supply unit 23. Further, the discharge port 38 corresponds to the discharge unit 24, and the mixing rotor 37 corresponds to the mixing unit.

  According to the mixer 31, while rotating the mixing rotor 37, the substrate is continuously supplied from the powder inlet 35 and the ammonia water is continuously supplied from the liquid inlet 36. In this way, the ammonia water is diffused in the outer circumferential direction along the horizontal surface 39 of the mixing rotor 37, while the substrate is agitated by joining the ammonia water on the horizontal surface 39. The substrate is given an impact force and a shearing force by colliding with the primary dispersion pin 41 while being stirred as described above.

  Next, the substrate flows down along the slope 40 of the mixing rotor 37 together with the ammonia water, and is pushed upward by the secondary dispersion pins 42. As a result, the ammonia water and the substrate are mixed, and the substrate mixture in which the ammonia water is uniformly impregnated is formed and continuously discharged from the discharge port 38.

  The treatment tank 21 can stir the supplied substrate and the ammonia water to apply shear force and impact force to the substrate, and mix the ammonia water and the substrate to form the substrate mixture. Anything that can be used is acceptable, and the present invention is not limited to the mixer 31 shown in FIG. As such a treatment tank 21, in addition to the mixer 31 shown in FIG. 2, a continuous jet mixer (for example, manufactured by Powder Research Powtex Co., Ltd., trade name: Flow Jet Mixer), a grindstone grinder (for example, Masuko Sangyo Co., Ltd.) Manufactured, trade name: Super Grinder).

  Next, in the saccharification pretreatment apparatus 1, the substrate mixture continuously discharged from the processing tank 21 by the discharge unit 24 and supplied to the silo 25 is stored in the silo 25. The substrate mixture passes through the silo 25 for a period in the range of 24-360 hours, for example 100 hours, without being heated, for example at a temperature of 25 ° C.

  At this time, the substrate has a concentration in the range of 20 to 30% by mass, for example, 25% by mass of ammonia water in a range of 0.7 to 1.3 parts by mass with respect to 1 part by mass of the substrate. For example, 1 part by mass is uniformly impregnated. Therefore, the substrate is subjected to the action of ammonia while passing through the silo 25, and lignin is dissociated from the substrate or the substrate is swollen. As a result, lignin is dissociated from the substrate, or a pre-saccharification product in which the substrate is swollen is formed.

  The saccharification pretreatment product is continuously taken out from the silo 25 by the powder feeder 3 a and supplied to the ammonia separation means 3. Since the pre-saccharification product is difficult to be discharged, the powder feeder 3a is directly connected directly below the silo 25, and has a function of forcibly cutting out the pre-saccharification product by a scraper and supplying it to the ammonia separation means 3. preferable. Examples of such a powder feeder 3a include a continuous quantitative feeder (for example, trade name: Smooth Auto Feeder CF300, manufactured by Daimori Industrial Co., Ltd.).

  The ammonia separation means 3 dissipates as ammonia gas by heating the saccharification pretreatment product to vaporize ammonia. The ammonia separation means 3 may be any one as long as it can heat the pre-saccharification product and dissipate ammonia gas. For example, a continuous conduction heat transfer dryer ( For example, Okawara Manufacturing Co., Ltd., a brand name: Inner tube rotary) etc. can be used.

  The pre-saccharification product from which ammonia has been separated by the ammonia separation means 3 is transferred to a subsequent enzymatic saccharification step by the transfer means 4.

  DESCRIPTION OF SYMBOLS 1 ... Pretreatment apparatus of lignocellulosic biomass, 2 ... Processing means, 3 ... Ammonia separation means, 21 ... Treatment tank, 22 ... Substrate supply means, 23 ... Ammonia water supply means, 24 ... Discharge means.

Claims (4)

A treatment means for adding aqueous ammonia to lignocellulosic biomass as a substrate, treating the resulting substrate mixture to dissociate lignin contained in the substrate, or swelling the substrate to obtain a pre-saccharification product ,
In a lignocellulosic biomass saccharification pretreatment apparatus comprising ammonia separation means for separating ammonia from the saccharification pretreatment product,
The processing means includes a processing tank,
Substrate supply means for continuously supplying the substrate to the treatment tank;
Ammonia water supply means for continuously supplying the ammonia water to the treatment tank;
Mixing means for stirring the substrate and the ammonia water supplied to the treatment tank to apply shearing force and impact force to the substrate and mixing the ammonia water and the substrate to obtain the substrate mixture; ,
Discharging means for continuously discharging the substrate mixture from the treatment tank;
The substrate mixture discharged by the discharging unit is stored for a predetermined time, and the storage unit dissociates lignin contained in the substrate in a non-heated state during storage or swells the substrate. A saccharification pretreatment device for lignocellulosic biomass. In the lignocellulosic biomass saccharification pretreatment device according to claim 1,
The pretreatment for saccharification of lignocellulosic biomass, wherein the storage means is disposed immediately below the treatment tank and connected to the treatment tank via the discharge means. In the lignocellulose biomass saccharification pretreatment device according to claim 1 or 2,
The ammonia water supply means supplies ammonia water having a concentration in a range of 20 to 30% by mass, and the ammonia water is supplied to the substrate supplied by the substrate supply means in a ratio of 1: 0.7 to 1: A saccharification pretreatment apparatus for lignocellulosic biomass, which is supplied at a mass ratio in the range of 1.3. In the lignocellulosic biomass pre-saccharification pretreatment device according to any one of claims 1 to 3,
The said storage means is equipped with the exhaust port which discharges | emits ammonia gas and air in the upper part, The saccharification pre-processing apparatus of the lignocellulosic biomass characterized by the above-mentioned.

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