Biofuel manufacturing method

Abstract

Provided is a biofuel production method that does not require pH adjustment as a pretreatment. This biofuel production method is provided with: a step for mixing land biomass, which is a land-derived raw material, with marine biomass, which is a marine-derived raw material; and a step for producing ethanol by fermenting the mixed raw materials.

Description

Technical Field

[0001] The present disclosure relates to biofuel production methods. Background Art

[0002] When producing biomass fuel, productivity such as the yield and speed of target products is required to be improved according to the characteristics of the biomass used.

[0003] For example, Patent Document 1 discloses a technology for improving productivity, such as parallel multiple fermentation (parallel subfermentation) in which the saccharification process is optimized using lignocellulose as terrestrial biomass.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-039295 Summary of the Invention

[0005] The inventors have discovered the following problems regarding the biofuel production method.

[0006] The technology disclosed in Patent Document 1 performs pH adjustment as a pretreatment on the biomass raw material. However, from the perspective of improving Life Cycle Assessment (LCA), there is a demand for the development of a biofuel production method that does not require pH adjustment as a pretreatment.

[0007] The present disclosure has been made in view of such problems, and an object of the present disclosure is to provide a method for producing biofuel that does not require pH adjustment as a pretreatment.

[0008] One solution for achieving the above object is a biofuel production method, comprising:

[0009] The process of mixing land-based materials with marine-based materials; and

[0010] The process of producing ethanol by fermenting mixed raw materials.

[0011] According to the present disclosure, a method for producing biofuel that does not require pH adjustment as a pretreatment can be provided.

[0012] The above and other objects, features and advantages of the present disclosure can be more fully understood from the detailed description and accompanying drawings given below. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is an enlarged schematic diagram of an example of mixed biomass according to an embodiment.

[0014] Figure 2 This is a flowchart showing an example of a biofuel production method according to an embodiment.

[0015] Figure 3 This is a diagram showing an example of the surface potential and particle size of biomass. DETAILED DESCRIPTION

[0016] The following describes the embodiments of the present disclosure in detail with reference to the accompanying drawings. In each of the drawings, the same or corresponding elements are given the same reference numerals, and repeated descriptions are omitted as needed to clarify the description. In addition, for ease of understanding, the scales of the various parts in the drawings may differ from the actual scales.

[0017] First, refer to Figure 1 An example of the structure of the mixed biomass used in the biofuel production method according to this embodiment, that is, the mixed biomass according to this embodiment, is described. The mixed biomass 10 according to this embodiment is a mixture produced using a plurality of biomass raw materials and is suitable for ethanol brewing. Figure 1 As shown, marine biomass 20 ( 20 a , 20 b , 20 c , 20 d ) and terrestrial biomass 30 are provided.

[0018] Marine biomass 20 is a raw material of marine origin. Marine biomass 20 is produced using, for example, seaweed. Terrestrial biomass 30 is a raw material derived from land. Terrestrial biomass 30 is produced using, for example, bamboo or sugarcane. Marine biomass 20 and terrestrial biomass 30 have different particle sizes. The method for measuring the particle size of terrestrial biomass 30 and marine biomass 20 is not particularly limited. The particle size of terrestrial biomass 30 and marine biomass 20 can be measured, for example, as a median particle size. For example, the median particle size of marine biomass 20 may be approximately one-fourth that of terrestrial biomass 30.

[0019] exist Figure 1 The figure shows a case where the marine biomass 20 has a smaller particle size than the terrestrial biomass 30. However, the marine biomass 20 may have a larger particle size than the terrestrial biomass 30. Since the marine biomass 20 and the terrestrial biomass 30 have different particle sizes, the marine biomass 20 and the terrestrial biomass 30 are more uniformly mixed and composited than when the marine biomass 20 and the terrestrial biomass 30 have approximately the same particle size.

[0020] Since marine biomass 20 and terrestrial biomass 30 are made of different materials, they typically have different pH values. Therefore, by adjusting the ratio of the mixed marine biomass 20 and terrestrial biomass 30, the pH of the mixed biomass 10 can be adjusted. Furthermore, since the mixed biomass 10 is composited with marine biomass 20 and terrestrial biomass 30, there is no internal pH bias. Therefore, the entire mixed biomass 10 reaches the target pH suitable for ethanol fermentation. The mixing ratio of marine biomass 20 and terrestrial biomass 30 is determined so that the pH of the mixed biomass 10 is, for example, approximately 5 to 8.

[0021] Next, refer to Figure 2 The process of the biofuel production method involved in this embodiment is described. In the biofuel production method involved in this embodiment, first, the marine biomass 20 and the terrestrial biomass 30 are crushed (step S101). In step S101, the marine biomass 20 and the terrestrial biomass 30 are crushed in a manner such that they have predetermined particle sizes, that is, different particle sizes. Specifically, for example, the marine biomass 20 can be crushed in a manner such that the median particle size of the particle size is greater than 100 μm and less than 300 μm. In addition, the terrestrial biomass 30 can be crushed in a manner such that the median particle size of the particle size is greater than 300 μm.

[0022] Next, the properties of the marine biomass 20 and the terrestrial biomass 30 are measured (step S102). Specifically, in step S102, the pH of each of the marine biomass 20 and the terrestrial biomass 30 is measured. Based on the pH measurement results in step S102, the mixing ratio of the marine biomass 20 and the terrestrial biomass 30 is determined. In step S102, the charge of the marine biomass 20 and the terrestrial biomass 30 is preferably further measured. Based on the charge measurement results in step S102, it can be determined whether the marine biomass 20 and the terrestrial biomass 30 require charge removal treatment.

[0023] Next, at least one of the marine biomass 20 and the terrestrial biomass 30 may be subjected to static removal (step S103). Step S103 may be performed when it is determined in step S102 that static removal is required. Figure 1 In the example shown, step S103 is performed after step S102, but step S103 may be performed simultaneously with step S102 or before step S102. The means for removing static electricity is not particularly limited, and static electricity may be removed by electrostatic adsorption using an ionizer, for example.

[0024] exist Figure 3 The relationship between the surface potential and particle size of each biomass when only the terrestrial biomass 30 is de-electrified is shown in FIG. Figure 3In the example shown, the particle size of the terrestrial biomass 30 is larger than that of the marine biomass 20. Therefore, from the perspective of suppressing the energy required for static elimination, Figure 3 In the example shown, only the terrestrial biomass 30 is decharged. Terrestrial biomass 30 is typically positively charged. Therefore, decharge is performed using an ionizer to bring the terrestrial biomass 30 closer to electrical neutrality. Meanwhile, the marine biomass 20 is typically positively charged. By performing step S103, the charge generated by the potential difference between the marine biomass 20 and the terrestrial biomass 30 allows the marine biomass 20 and the terrestrial biomass 30 to be more evenly mixed and composited.

[0025] In addition, Figure 3 In the example shown, only the terrestrial biomass 30 is de-electrified. However, it is also possible to de-electrify only the marine biomass 20, or both the marine biomass 20 and the terrestrial biomass 30. Furthermore, to further strengthen the composite particle structure, the terrestrial biomass 30 can be negatively charged, while the marine biomass 20 can be uniformly positively charged. In this case, the electrostatic bond between the terrestrial biomass 30 and the marine biomass 20 becomes even stronger.

[0026] Back to Figure 2 Continuing the description, the marine biomass 20 and the terrestrial biomass 30 are then mixed (step S104). In step S104, the marine biomass 20 and the terrestrial biomass 30 are mixed at a mixing ratio determined based on the pH measured in step S102 to produce the mixed biomass 10. Because the marine biomass 20 and the terrestrial biomass 30 have different particle sizes, the marine biomass 20 and the terrestrial biomass 30 are uniformly mixed and composited within the mixed biomass 10. Consequently, there is no pH bias within the mixed biomass 10.

[0027] In general, biomass has a variety of components, and components are often localized. Because the charge characteristics vary depending on the content ratio and localization of the components, simply mixing different biomasses often results in particles coming into contact with each other, positively influencing each other's charge and causing particle aggregation. Therefore, to reliably combine different biomasses, it is preferable to adjust the charge state of each biomass before mixing.

[0028] Next, ethanol is produced by fermenting the mixed biomass 10 (step S105). In step S105, generally, after a saccharification process using an enzyme reaction is performed, a fermentation process using yeast is performed. The detailed steps for implementing step S105 can be performed by a known method. In the biofuel production method involved in the present embodiment, the pH of the mixed biomass is adjusted by mixing the marine biomass 20 and the terrestrial biomass 30. Therefore, it is possible to prepare a mixed biomass with a pH suitable for the saccharification process and the fermentation process without adding an alkali or an acid to the mixed biomass. In this way, the biofuel production method involved in the present embodiment does not require pH adjustment as a pretreatment. Therefore, LCA can be improved, and in addition, manufacturing costs can be suppressed.

[0029] Furthermore, the biofuel production method according to this embodiment combines marine biomass 20 and terrestrial biomass 30, allowing reactions in the saccharification and fermentation steps to be performed while maintaining a predetermined pH overall. Consequently, reaction inhibition due to localized alkali or acidic conditions in each step is avoided, enabling efficient ethanol production.

[0030] In addition, the present disclosure is not limited to the above-described embodiment, and can be appropriately modified within a scope not departing from the spirit and scope of the present disclosure.

[0031] From the disclosure thus described, it is obvious that the embodiments of the present disclosure may be varied in various ways. Such variations are not to be regarded as a departure from the spirit and scope of the present disclosure, and all such modifications are intended to be included within the scope of the appended claims as obvious to one skilled in the art.

Claims

1. A method for producing biofuel, comprising: The process of mixing raw materials from land and marine sources; and The process of producing ethanol by fermenting mixed raw materials.

2. The biofuel production method according to claim 1, The median particle size of the land-derived raw material is 300 μm or more, The median particle size of the marine-derived raw material is 100 μm or more and 300 μm or less.

3. The biofuel production method according to claim 1 or 2, Prior to the mixing step, the method further includes removing static electricity from at least one of the land-derived raw material and the ocean-derived raw material.

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