Method and system for reducing amount of carbon dioxide emission

Abstract

To provide a method and a system for reducing the amount of carbon dioxide emission in a bioethanol production process.SOLUTION: A method for reducing the amount of carbon dioxide emission according to the present disclosure comprises the steps of: fermenting a plant-derived material thereby producing bioethanol; recovering carbon dioxide generated during production of a bioethanol; incinerating a residue of the bioethanol thereby generating incineration ash; and reacting the carbon dioxide recovered during the production of the bioethanol with the incineration ash thereby generating carbonate.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to methods and systems for reducing carbon dioxide emissions. [Background technology]

[0002] Patent Document 1 discloses technology related to bioethanol. Raw materials for bioethanol include sugars such as sugarcane. Alternatively, starch-based raw materials such as rice, wheat, and corn can be used as raw materials for bioethanol. Furthermore, cellulosic raw materials such as thinned wood, construction waste, rice straw, and bagasse sugar can also be used as raw materials for bioethanol.

[0003] When using starch-based raw materials, they are saccharified using enzymes. When using cellulosic raw materials, the cellulosic raw materials are pretreated with hot compressed water, acid, and alkali, and then saccharified using saccharifying enzymes. Bioethanol is then produced by ethanol fermentation, distillation, and dehydration of the raw sugar or the saccharified raw material. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2015 / 16375 Summary of the Invention [Problem to be solved by the invention]

[0005] When producing bioethanol, carbon dioxide is generated during the ethanol fermentation of sugars, etc. In recent years, there has been a demand for technologies to reduce the amount of carbon dioxide generated as a measure against global warming.

[0006] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a method and system for reducing the amount of carbon dioxide generated that effectively reduces the amount of carbon dioxide generated. [Means for solving the problem]

[0007] The method for reducing carbon dioxide emissions disclosed herein includes the steps of fermenting plant-derived raw materials to produce bioethanol, recovering carbon dioxide generated during the production of the bioethanol, incinerating the bioethanol residue to produce incineration ash, and reacting the carbon dioxide recovered during the production of the bioethanol with the incineration ash to produce carbonates.

[0008] The above-mentioned method for reducing the amount of carbon dioxide generated may further include a step of recovering carbon dioxide generated during the incineration of the residue, and a step of reacting the carbon dioxide recovered during the incineration of the residue with the incineration ash to produce the carbonate.

[0009] In the method for reducing the amount of carbon dioxide generated, fertilizer may be produced from the carbonate.

[0010] In the method for reducing the amount of carbon dioxide generated, the fertilizer may be used as fertilizer for plants that are used as raw materials for bioethanol production.

[0011] The carbon dioxide generation reduction system according to the present disclosure includes a fermentation means for fermenting plant-derived raw materials to produce bioethanol, a recovery means for recovering carbon dioxide generated during the production of the bioethanol, an incineration means for generating incineration ash by incinerating the bioethanol residue, and a generation means for reacting the carbon dioxide recovered during the production of the bioethanol with the incineration ash to produce carbonates. [Effects of the Invention]

[0012] According to the present disclosure, it is possible to provide a method and system for reducing the amount of carbon dioxide generated in a bioethanol production process, which effectively reduce the amount of carbon dioxide generated. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a block diagram showing the overall configuration of a system for reducing the amount of carbon dioxide generation. [Figure 2] 1 is a flowchart showing a method for reducing carbon dioxide generation. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the invention according to the claims is not limited to the following embodiments. Furthermore, not all of the configurations described in the embodiments are necessarily essential means for solving the problems. For clarity of explanation, the following description and drawings have been omitted and simplified as appropriate. In each drawing, the same elements are given the same reference numerals, and duplicate explanations are omitted as necessary.

[0015] The system according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a schematic diagram showing the overall configuration of a system 100 for reducing the amount of carbon dioxide generation (also simply referred to as system 100). System 100 reduces carbon dioxide generated during bioethanol production. Therefore, system 100 is installed in a bioethanol plant.

[0016] The system 100 includes a fermentation section 20, a first recovery section 30, an incineration section 40, and a production section 50. The system 100 may also include a second recovery section 60 and a fertilizer production section 70.

[0017] The fermentation unit 20 produces bioethanol 23 by fermenting plant-derived raw materials 10. Examples of plant-derived raw materials 10 include sugars such as sugarcane and sugar beets. Alternatively, bioethanol raw materials 10 include starch-based raw materials such as rice, wheat, corn, sorghum, potato, sweet potato, cassava, and other root vegetables. Furthermore, bioethanol raw materials 10 include cellulosic raw materials such as thinned wood, construction waste, rice straw, and bagasse sugar. It is preferable that the plants used as raw materials 10 are inedible.

[0018] When a starch-based raw material is used, the fermentation unit 20 saccharifies the starch-based raw material with enzymes. When a cellulosic raw material is used, the fermentation unit 20 pretreats the cellulosic raw material with compressed hot water, acid, and alkali, and saccharifies it with saccharifying enzymes or the like. The fermentation unit 20 ferments the sugar in the raw material 10 into ethanol (alcohol fermentation). The fermentation unit 20 then distills and dehydrates the ethanol-fermented product to produce bioethanol 23.

[0019] Furthermore, carbon dioxide 21 is produced during ethanol fermentation. During ethanol fermentation, sugars are decomposed to produce bioethanol 23 and carbon dioxide 21. For example, the chemical formula for ethanol fermentation is shown below (1).

[0020] C6H 12 O6 → 2C2H5OH + 2CO2 (1)

[0021] As shown in formula (1), two molecules of ethanol and two molecules of carbon dioxide are produced from one molecule of glucose. Carbon dioxide 21 generated in the ethanol fermentation process is supplied to the first recovery unit 30. In other words, the first recovery unit 30 recovers the carbon dioxide 21 generated during the production of bioethanol 23. The carbon dioxide concentration of the gas generated in the ethanol fermentation process is high, at approximately 50%. The first recovery unit 30 may also have a filter or the like to increase the carbon dioxide concentration.

[0022] Furthermore, during ethanol fermentation, residue 22 is generated. Residue 22 is the residue left over from raw material 10 in the ethanol fermentation process. For example, bioethanol 23 and residue 22 can be separated by filtering raw material 10 after fermentation. Plant-derived residue 22 is supplied to incineration unit 40.

[0023] The incineration unit 40 incinerates the residue 22 to generate incineration ash 41. The incineration ash 41 contains calcium (Ca), potassium (K), and magnesium (Mg). The incineration unit 40 supplies the incineration ash 41 to the generation unit 50.

[0024] The production unit 50 reacts the carbon dioxide 21 recovered during the production of bioethanol 23 with the incineration ash 41 to produce carbonates 51. The carbon dioxide 21 can be immobilized by reacting it with calcium, potassium, and magnesium to form carbonates. The production unit 50 can immobilize the carbon dioxide 21 by producing carbonates 51 such as calcium carbonate (CaCO3), potassium carbonate (K2CO3), calcium bicarbonate (Ca(HCO3)2), and magnesium carbonate (MgCO3).

[0025] For example, the generating unit 50 dissolves the incineration ash 41 in water, a chemical solution, or the like, thereby eluting calcium, magnesium, and potassium. The generating unit 50 supplies carbon dioxide 21 to this solution. Specifically, the generating unit 50 has a scrubber. An aqueous solution containing the incineration ash 41 and the carbon dioxide 21 are supplied to the scrubber. The scrubber treats the exhaust gas using an aqueous solution containing carbon dioxide gas as a treatment liquid.

[0026] For example, the scrubber is connected to a tank for storing an aqueous solution and an inlet for introducing carbon dioxide gas. The scrubber also has a nozzle for generating bubbles. Through the operation of the scrubber, carbon dioxide is fixed to calcium, magnesium, or potassium contained in the aqueous solution. Carbonates 51 such as calcium carbonate (CaCO3), potassium carbonate (K2CO3), calcium bicarbonate (Ca(HCO3)2), and magnesium carbonate (MgCO3) are produced.

[0027] In this way, the first recovery section 30 recovers the carbon dioxide 21 generated during ethanol fermentation. Furthermore, the carbon dioxide 21 is recovered using the incineration ash 41 of the residue 22 generated during the production of bioethanol 23. In other words, the carbon dioxide is immobilized using calcium, potassium, magnesium, or the like contained in the incineration ash 41. This makes it possible to efficiently reduce the amount of carbon dioxide generated. The gas generated during ethanol fermentation has a high carbon dioxide concentration, so it can be immobilized efficiently. The plants that serve as the raw material 10 also absorb carbon dioxide during their growth, further reducing the amount of carbon dioxide generated.

[0028] Furthermore, the residue 22 or the carbonates 51 may be supplied to a fertilizer production unit 70. The fertilizer production unit 70 produces fertilizer 71 using the residue 22 or the carbonates 51 as raw materials. Because the residue 22 and the carbonates 51 contain calcium carbonate, potassium carbonate, and magnesium carbonate, the fertilizer 71 can be produced efficiently. The fertilizer 71 may be used to grow raw materials for bioethanol 23. That is, the fertilizer 71 is supplied to a field or the like containing the raw material 10. For example, the fertilizer 71 is used for plant cultivation, soil improvement, and the like. In this way, a circulation loop that can efficiently reduce carbon dioxide can be formed.

[0029] When calcium carbonate (CaCO3), potassium carbonate (K2CO3), calcium bicarbonate (Ca(HCO3)2), magnesium carbonate (MgCO3), etc. are given to plants as fertilizer, it circulates as a cycle, making it efficient. As plants grow, carbon dioxide is absorbed through photosynthesis, and carbohydrates such as glucose are produced. Therefore, carbon dioxide is absorbed even as the plants grow. Since fertilizer 71 is used to grow the plants, the plants can be cultivated efficiently. In addition, carbon dioxide generated during the production of bioethanol 23 can be captured. Furthermore, the captured carbon dioxide 21 and carbon dioxide 42 can be used to produce fertilizer 71. Therefore, the amount of carbon dioxide generated can be reduced throughout the entire circulation loop.

[0030] Furthermore, carbon dioxide 42 is generated during the incineration of residue 22. Second recovery section 60 recovers carbon dioxide 42 generated during the incineration of residue 22 and supplies it to generation section 50. Generation section 50 carbonates carbon dioxide 42 recovered in second recovery section 60. This makes it possible to further efficiently reduce the amount of carbon dioxide generated.

[0031] Furthermore, if sufficient amounts of calcium, potassium, magnesium, etc. are not obtained in the production unit 50, calcium, potassium, magnesium, etc. may be supplied from the outside. For example, rocks containing calcium, potassium, magnesium, etc. may be supplied from the outside. Furthermore, the substances produced in the production unit 50 may be used in building materials such as cement and concrete.

[0032] 2 is a flowchart showing a method for reducing the amount of carbon dioxide generated. First, the fermentation unit 20 ferments the plant-derived raw material 10 to produce bioethanol 23 (S11). The fermentation unit 20 decomposes sugars to produce bioethanol 23 and carbon dioxide 21. Furthermore, a residue of the raw material 10 is produced. The first recovery unit 30 recovers the carbon dioxide 21 generated during the production of the bioethanol 23 (S12).

[0033] The incineration unit 40 incinerates the residue 22 of the bioethanol 23 to produce incineration ash 41 (S13). The carbon dioxide 21 recovered during the production of the bioethanol 23 is reacted with the incineration ash 41 to produce carbonates (S14).

[0034] In this way, the method according to this embodiment can reduce the amount of carbon dioxide generated. Furthermore, this method can produce bioethanol 23 and fertilizer. Therefore, the method according to this embodiment can also be used as a method for producing bioethanol 23 and a method for producing fertilizer.

[0035] The present disclosure is not limited to the above-described embodiments and can be modified as appropriate without departing from the spirit of the present disclosure. The present disclosure also contributes to carbon neutrality, decarbonization, and the Sustainable Development Goals (SDGs). [Explanation of symbols]

[0036] 100 systems 10 Raw materials 20 Fermentation Department 21 Carbon dioxide 22 Residue 23 Bioethanol 30 First Collection Section 40 Incineration Department 41 Incineration ash 42 Carbon dioxide 50 Generation part 51 Carbonates 60 Second Recovery Section 70 Fertilizer generation department 71 Fertilizer

Claims

1. fermenting a plant-derived raw material to produce bioethanol; A step of recovering carbon dioxide generated during the production of the bioethanol; Incineration of the bioethanol residue to generate incineration ash; The carbon dioxide recovered during the production of bioethanol is reacted with the incineration ash to produce carbonates. Methods for reducing carbon dioxide emissions.

2. recovering carbon dioxide generated during incineration of the residue; 2. The method for reducing the amount of carbon dioxide generated according to claim 1, further comprising the step of reacting carbon dioxide recovered during the incineration of the residue with the incineration ash to produce the carbonate.

3. The method for reducing the amount of carbon dioxide generated according to claim 1 or 2, wherein fertilizer is produced from the carbonate.

4. The method for reducing the amount of carbon dioxide generated according to claim 3, wherein the fertilizer is used as fertilizer for plants that are used as raw materials for bioethanol production.

5. a fermentation means for fermenting a plant-derived raw material to produce bioethanol; A recovery means for recovering carbon dioxide generated during the production of the bioethanol; incineration means for generating incineration ash by incinerating the bioethanol residue; and a generating means for generating carbonate by reacting the carbon dioxide recovered during the production of the bioethanol with the incineration ash. Carbon dioxide emission reduction system.

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