JP2013059284A - Ethanol production apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ethanol production apparatus which can smoothly and efficiently operates a distillation column system when a fermented solution obtained from biomass is concentrated.SOLUTION: The ethanol production apparatus 1 includes a fermentation means 4, a distillation means 5, and a transport means 43 for transporting the fermented solution from the fermentation means 4 to the distillation means 5. The transport means 43 is provided with a separating means 45 that catches protein and an inorganic ion contained in the fermented solution on the way to separate. The separating means 45 is provided with an ion-exchange resin which has macropores of an opening diameter more than 500 Å or more and the surface of the macropore is modified with a hydroxyl or carboxyl group.

Description

  The present invention relates to an ethanol production apparatus.

  Conventionally, an ethanol production apparatus for producing bioethanol by saccharifying a substrate mixture obtained by mixing biomass with a solvent using a saccharification enzyme produced by a microorganism and fermenting the obtained saccharified solution is known. In the ethanol production apparatus, the fermentation solution obtained by fermentation of the saccharified solution is concentrated by distillation and further dehydrated, whereby ethanol having a concentration of, for example, about 99.9% by mass can be obtained (for example, Patent Document 1). reference).

  As one of the biomasses serving as the substrate, lignocellulosic biomass such as rice straw can be mentioned. The lignocellulosic biomass has a structure in which lignin is firmly bound to cellulose or hemicellulose. Therefore, by holding the substrate mixture at a predetermined temperature for a predetermined time, the lignin is dissociated from the substrate or the substrate is swollen to obtain a saccharification pretreatment product that enables saccharification of cellulose or hemicellulose. Enzymatic saccharification of processed products has been performed.

  In addition, in this application, dissociation means cut | disconnecting at least one part coupling | bonding among the binding sites of the lignin couple | bonded with the cellulose or hemicellulose of lignocellulosic biomass. Swelling means that voids are generated in cellulose or hemicellulose constituting crystalline cellulose by the intrusion of liquid, or voids are generated inside cellulose fibers to expand.

  In the ethanol production apparatus using the lignocellulosic biomass as a substrate, the saccharification solution is fermented with fermenting bacteria or yeast to obtain the fermentation solution. At this time, although the density | concentration of the said fermentation solution is based also on the performance of the said fermenting microbe or yeast, generally it will be a low concentration of about 5-10 mass%. As a result, when distilling and concentrating the obtained fermentation solution, the required thermal energy increases, and the energy required for concentration of the fermentation solution is 30-50% of the energy required for the entire ethanol production process. There is a problem of occupying a large proportion.

  In order to solve the above problem, it is desired to reduce thermal energy by increasing the efficiency of the fermentation solution concentration step in the ethanol production apparatus.

JP 2010-65001 A

  However, when a distillation tower system is used to concentrate the fermentation solution obtained from the biomass, deposits are deposited in the distillation tower system, causing clogging of the piping and the distillation tower, and the like. There is an inconvenience that smooth operation of the vehicle may be hindered.

  Therefore, the present invention provides an ethanol production apparatus that can solve the above inconvenience and can smoothly and efficiently operate the distillation column system when the fermentation solution obtained from the biomass is concentrated. Objective.

  To achieve this object, the present invention provides a fermentation means for fermenting a biomass saccharified solution, a distillation means for distilling the fermentation solution obtained by the fermentation means, and the fermentation solution from the fermentation means to the distillation means. In the ethanol production apparatus comprising the transfer means for transferring to the medium, the transfer means includes a separation means for capturing and separating the protein and inorganic ions contained in the fermentation solution in the middle, and the separation means has an opening diameter of 500 mm or more. And an ion exchange resin in which the surface of the macropore is modified with a hydroxyl group or a carboxyl group.

  As a result of examining the precipitate from the fermentation solution deposited and deposited in the distillation means such as the distillation tower system, the present inventors found that the precipitate is an enzyme used for the saccharification or a fermenting bacterium used for the fermentation. Or it discovered that it was a composite_body | complex of the protein derived from a yeast cell, and an inorganic compound. The inorganic ions forming the inorganic compound are considered to be components of the biomass itself, phosphorus ions derived from the medium used for culturing the fermenting bacteria or yeast, manganese ions, and the like.

  Therefore, the ethanol production apparatus of the present invention captures the protein and inorganic ions by the separation means provided in the middle of the transfer means for transferring the fermentation solution from the fermentation means to the distillation means based on the knowledge. To separate. As a result, in the ethanol production apparatus of the present invention, the fermentation solution substantially free of the protein and inorganic ions is supplied to the distillation means, and deposits are prevented from being deposited in the distillation means. Thus, the distillation means can be operated smoothly and efficiently, and the required heat energy can be reduced.

  In the ethanol production apparatus of the present invention, the separation means includes an ion exchange resin having a macropore having an opening diameter of 500 mm or more and the surface of the macropore being modified with a hydroxyl group or a carboxyl group. According to the ion exchange resin, the protein can be captured and separated by a macropore having an opening diameter of 500 mm or more, and inorganic ions such as phosphorus ions and manganese ions are captured by the hydroxyl group or carboxyl group (carboxylic acid group). Can be separated.

  In the ethanol production apparatus of the present invention, the separation means preferably includes activated carbon. Since the activated carbon can capture the protein, the separation means can include activated carbon to reduce the load of the ion exchange resin.

  Moreover, the ethanol manufacturing apparatus of this invention WHEREIN: It is preferable that the said transfer means is equipped with the filtration means which consists of a microfiltration membrane in the upstream of the said separation means. Since the microfiltration membrane can capture components having a high molecular weight such as fermenting bacteria or yeast cells in the protein, the load of the ion exchange resin can be further reduced.

  Moreover, in the ethanol production apparatus of the present invention, the fermentation solution has a protein content after being processed by the separation means, wherein the protein content is 0.10 or less as the absorbance of light having a wavelength of 610 nm, and the phosphorus ion content Is 140 μg or less per 1 g of the fermentation solution, and the manganese ion content is preferably 50 μg or less per 1 g of the fermentation solution.

  The absorbance of light of each wavelength is an indicator of the amount of protein contained in the fermentation solution, and when the absorbance of the light of each wavelength is in the range, the fermentation solution is supplied to the distillation means. In addition, it is possible to prevent deposits from being deposited in the distillation means. Further, the fermentation solution has a phosphorus ion content and a manganese ion content within the above ranges, so that when the fermentation solution is supplied to the distillation means, deposits are deposited and deposited in the distillation means. Can be prevented.

  When the protein content is out of the above range, or the phosphorus ion content or the manganese ion content is out of the above range, when the fermentation solution is supplied to the distillation unit, deposits adhere to the distillation unit. May accumulate.

  In the ethanol production apparatus of the present invention, for example, lignocellulosic biomass can be used as the biomass.

The system block diagram which shows the structure of the ethanol manufacturing apparatus of this invention.

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

  As shown in FIG. 1, the ethanol production apparatus 1 of this embodiment includes a pretreatment device 2, a saccharification treatment device 3, a fermentation treatment device 4, and a distillation tower system 5.

  The pretreatment device 2 includes a raw material supply device 21, an ammonia water supply device 22, a stirring tank 23, a storage tank 24, and a transfer conduit 25. The raw material supply device 21 supplies the raw material substrate to the stirring tank 23, and the ammonia water supply device 22 supplies ammonia water to the stirring tank 23. As the substrate, lignocellulosic biomass such as rice straw can be used.

  The agitation tank 23 agitates and mixes the substrate and the aqueous ammonia, and supplies the obtained substrate mixture to the storage tank 24. While the substrate mixture is stored for a predetermined time, the storage tank 24 dissociates lignin from the substrate without heating or swells the substrate to obtain a pre-saccharification product.

  The saccharification pretreatment product is taken out by a transfer conduit 25 connected to the bottom of the storage tank 24, and after ammonia is separated by a solid-liquid separation device 26 provided in the middle of the transfer conduit 25, ammonia separation saccharification pretreatment is performed. The product is sent to the saccharification treatment apparatus 3 as a product. The solid-liquid separator 26 includes a recovery conduit 27 that recovers the separated ammonia as aqueous ammonia. The recovery conduit 27 is connected to the ammonia water supply device 22.

  The saccharification treatment apparatus 3 includes a saccharification treatment tank 31. A transfer conduit 25 is connected to the upper part of the saccharification treatment tank 31, and a saccharification enzyme supply device 32 is provided. A transfer conduit 33 for transferring the saccharified solution obtained in the saccharification treatment tank 31 to the fermentation treatment apparatus 4 is connected to the bottom of the saccharification treatment tank 31. In the middle of the transfer conduit 33, a solid-liquid separator 34 is provided to separate and remove the rice straw residue and the like contained in the saccharified solution.

  The fermentation treatment apparatus 4 includes a fermentation treatment tank 41, and a transfer conduit 33 is connected to the upper part of the fermentation treatment tank 41 and a fungus body supply apparatus 42 is provided. A transfer conduit 43 for transferring the fermentation solution obtained in the fermentation treatment tank 41 to the distillation tower system 5 is connected to the bottom of the fermentation treatment tank 41.

  In the middle of the transfer conduit 43, a filtration device 44 made of a microfiltration membrane and a separation device 45 for capturing and separating proteins and inorganic compounds contained in the fermentation solution are provided.

  Examples of the microfiltration membrane include those made of a resin such as polyethylene, polystyrene, and polyvinylidene fluoride, and having a pore diameter in the range of 0.1 to 0.25 μm. According to the microfiltration membrane, components having a large molecular weight such as fermenting bacteria or yeast cells can be captured and separated from the protein.

  As the separation device 45, one having an ion exchange resin and activated carbon can be used. Examples of the ion exchange resin include weakly acidic cation exchange resins made of a copolymer of acrylic and divinylbenzene. The weakly acidic cation exchange resin has a macropore having an opening diameter of 500 to 1000 mm, and the surface of the macropore is modified with a hydroxyl group or a carboxyl group (carboxylic acid group).

  According to the weakly acidic cation exchange resin, as an original function of the cation exchange resin, cations (inorganic ions) such as phosphorus ions and manganese ions in the fermentation solution can be captured and separated, and the macropores can be separated. Can capture and separate proteins.

  Moreover, according to the activated carbon, proteins can be captured and separated. In the separation device 45, the activated carbon may be provided integrally with the ion exchange resin, or may be provided separately.

  The distillation column system 5 includes a mash column 51, a rectifying column 52, and a dehydrator 53, and a transfer conduit 43 is connected to the upper portion of the mash column 51. The mash column 51 includes a transfer conduit 54 for transferring the column top liquid to the rectification column 52, and the rectification column 52 includes a transfer conduit 55 for transferring the column top liquid to the dehydrator 53, and the column bottom liquid mashing column 51. And a reflux conduit 56 for refluxing. The moromi tower 51 and the rectifying tower 52 are each provided with a heating device and a condenser (not shown). As the heating device, for example, devices for blowing steam into the bottoms of the mash column 51 and the rectifying column 52 can be used.

  Next, the operation of the ethanol production apparatus 1 will be described.

  In the ethanol production apparatus 1, first, rice straw as a substrate supplied from the raw material supply apparatus 21 and ammonia water supplied from the ammonia water supply apparatus 22 are stirred in the stirring tank 23 to obtain a substrate mixture. The obtained substrate mixture is supplied to a storage tank 24 connected directly below the stirring tank 23, and stored in the storage tank 24 for a predetermined time, thereby dissociating lignin from the rice straw without heating, Alternatively, a pre-saccharification product is obtained by swelling the rice straw.

  Since the pre-saccharification product contains aqueous ammonia, ammonia is separated by the solid-liquid separation device 26 provided in the middle of the transfer conduit 25 while being transferred to the saccharification treatment tank 31 by the transfer conduit 25. . As a result, the ammonia separation saccharification pretreatment product from which ammonia has been separated is transferred to the saccharification treatment tank 31. On the other hand, the ammonia separated by the solid-liquid separator 26 is recovered as ammonia water by the recovery conduit 27 and is returned to the ammonia water supply device 22.

  In the saccharification treatment tank 31, the saccharification enzyme supplied from the saccharification enzyme supply device 32 is mixed with the ammonia separation saccharification pre-treatment product supplied via the transfer conduit 25, and held for a predetermined time. As a result, a saccharified solution obtained by saccharifying cellulose, hemicellulose and the like contained in rice straw as the substrate is obtained.

  The saccharification solution is taken out by a transfer conduit 33 connected to the bottom of the saccharification treatment tank 31, and the rice straw residue and the like are separated and removed by a solid-liquid separation device 34 provided in the middle of the transfer conduit 33. Then, it is transferred to the fermentation treatment tank 41.

  In the fermentation treatment tank 41, the fermented bacteria or yeast supplied from the microbial cell supply device 42 is mixed with the saccharified solution supplied via the transfer conduit 33 and held for a predetermined time. As a result, the sugar contained in the saccharified solution is ethanol-fermented with the fermenting bacteria or yeast, and a fermentation solution containing ethanol is obtained.

  The fermentation solution is taken out by a transfer conduit 43 connected to the bottom of the fermentation treatment tank 41 and transferred to the mash tower 51. Here, the fermentation solution is a protein derived from the saccharifying enzyme, the fermenting bacterium or yeast, and components of the rice straw itself, or a phosphorus ion derived from a medium used for culturing the fermenting bacterium or yeast, Contains cations (inorganic ions) such as manganese ions. Therefore, when the fermentation solution is transferred without any treatment, there is a concern that deposits may be deposited on the mash column 51, the rectifying column 52, the transfer conduits 54 and 55, the reflux conduit 56, and the like.

  Therefore, the fermentation solution is first supplied to a filtration device 44 provided in the middle of the transfer conduit 43, and components having a high molecular weight such as fermentation bacteria or yeast cells are removed from the protein by the microfiltration membrane. The

  Next, the fermentation solution is supplied to the separation means 45 via the transfer conduit 43. The fermentation solution is separated by capturing and separating proteins that have not been removed by the microfiltration membrane of the filtration device 44 by activated carbon and ion exchange resin provided in the separation means 45, while phosphorus ions and manganese ions are exchanged by the ion exchange. It is captured and separated by the resin.

  As a result, the fermentation solution has a protein content of 0.10 or less as the absorbance of light having a wavelength of 610 nm. The fermentation solution has a phosphorus ion content of 140 μg or less per gram of the fermentation solution and a manganese ion content of 50 μg or less per gram of the fermentation solution.

  The fermentation solution is supplied to the mash tower 51 after the inorganic compound is adsorbed by the filtration device 45 and the protein is filtered and removed. In the moromi tower 51, the fermentation solution is distilled to obtain a first ethanol solution containing a higher concentration of ethanol than the fermentation solution as a tower top liquid. The first ethanol solution is taken out from the top of the mash column 51 and transferred to the rectification column 52 through the transfer conduit 54.

  In the rectifying column 52, the first ethanol solution is subjected to rectification, whereby a second ethanol solution containing ethanol having a higher concentration than the first ethanol solution is obtained as a column top liquid. The second ethanol solution is taken out from the top of the rectifying column 52, transferred to the dehydrating device 53 through the transfer conduit 55, and dehydrated. As a result, ethanol having a concentration of about 99.9% by weight can be obtained as a product.

  In the ethanol production apparatus 1 of the present embodiment, the protein and the inorganic compound contained in the fermentation solution are removed on the upstream side of the distillation column system 5, so that deposits are deposited in the distillation column system 5. Can be prevented. Therefore, according to the ethanol production apparatus 1 of the present embodiment, the distillation tower system 5 can be operated smoothly and efficiently, and the required heat energy can be reduced.

  In the ethanol production apparatus 1 of this embodiment, the filtration device 44 including the microfiltration membrane is provided, but only the separation device 45 may be provided without providing the filtration device 44. Moreover, in the ethanol production apparatus 1 of the present embodiment, the separation device 45 is provided with activated carbon and an ion exchange resin, but may be provided with only the ion exchange resin without providing activated carbon. However, when the microfiltration membrane or activated carbon is not used, the load of the ion exchange resin may increase.

  DESCRIPTION OF SYMBOLS 1 ... Ethanol manufacturing apparatus, 2 ... Pre-processing apparatus, 3 ... Saccharification processing apparatus, 4 ... Fermentation processing apparatus, 5 ... Distillation tower system, 44 ... Filtration apparatus, 45 ... Separation apparatus.

Claims (5)

In an ethanol production apparatus comprising fermentation means for fermenting a saccharified solution of biomass, distillation means for distilling the fermentation solution obtained by the fermentation means, and transfer means for transferring the fermentation solution from the fermentation means to the distillation means ,
The transfer means includes a separation means for capturing and separating proteins and inorganic ions contained in the fermentation solution in the middle, and the separation means has a macropore having an opening diameter of 500 mm or more, and the surface of the macropore is a hydroxyl group or carboxyl. An ethanol production apparatus comprising an ion exchange resin modified with a group.   The ethanol production apparatus according to claim 1, wherein the separation unit includes activated carbon.   3. The ethanol production apparatus according to claim 1, wherein the transfer unit includes a filtration unit including a microfiltration membrane on an upstream side of the separation unit.   The ethanol production apparatus according to any one of claims 1 to 3, wherein the fermentation solution has a protein content of 0.10 or less as the absorbance of light having a wavelength of 610 nm after being processed by the separation means. An ethanol production apparatus, wherein the phosphorus ion content is 140 μg or less per gram of the fermentation solution, and the manganese ion content is 50 μg or less per gram of the fermentation solution.   The ethanol production apparatus according to any one of claims 1 to 4, wherein the biomass is lignocellulosic biomass.

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