Biomass liquid fuel manufacturing method, slurry fuel and its manufacturing method, and wood biomass resource recovery method

Abstract

To provide a manufacturing method for manufacturing high-quality biomass liquid fuel having an excellent handleability by using woody biomass as a raw material.SOLUTION: A manufacturing method of biomass liquid fuel comprises: a first step of heating woody biomass 36 to 400 to 700°C and separating the resulting material into decomposition gas and woody biomass residue; and a second step of recovering a biomass liquid fuel by cooling the decomposition gas to 0 to 100°C. A heating time of the woody biomass in the first step is 1 to 40 minutes.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for producing biomass liquid fuel, a slurry fuel and a method for producing the same, and a method for converting wood biomass into a resource. [Background technology]

[0002] From the viewpoint of preventing global warming and creating a recycling-oriented society, there has been a growing movement to expand the use of biomass under the concept of carbon neutrality. As an alternative to thermal energy derived from fossil fuels, for example, the use of woody biomass for power generation and bioethanol as automobile fuel are being promoted.

[0003] In recent years, a method of converting woody biomass into fuel has attracted attention in which woody biomass is rapidly heated for rapid pyrolysis, and the resulting gas is cooled to recover the oil content (see, for example, Patent Documents 1 to 4). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4371433 [Patent Document 2] JP 2012-236924 A [Patent Document 3] JP 2010-116536 A [Patent Document 4] JP 2014-190882 A Summary of the Invention [Problem to be solved by the invention]

[0005] A main object of the present invention is to provide a method for producing biomass liquid fuel that is capable of producing high-quality biomass liquid fuel that is easy to handle, using wood biomass as a raw material. [Means for solving the problem]

[0006] One aspect of the present invention relates to a method for producing biomass liquid fuel. The method for producing biomass liquid fuel includes a first step of heating woody biomass to 400 to 700°C and separating it into decomposition gas and woody biomass residue, and a second step of cooling the decomposition gas to 0 to 100°C and recovering biomass liquid fuel. The heating time of the woody biomass in the first step is 1 to 40 minutes. According to this production method, it is possible to produce high-quality biomass liquid fuel that is easy to handle and has a high calorific value.

[0007] The first step may be carried out in a rotary kiln furnace, a stoker furnace, or a batch furnace. Since a rotary kiln furnace, a stoker furnace, or a batch furnace is an existing facility, the cost of producing biomass liquid fuel can be reduced by selecting such a facility.

[0008] The maximum particle size of the woody biomass may be equal to or greater than 1.18 mm and less than 106 mm.

[0009] The woody biomass may include crushed construction waste wood and / or forest residues. Since crushed construction waste wood and crushed forest residues are low-quality woody biomass containing a mixture of various tree species, the use of such woody biomass can reduce the cost of producing biomass liquid fuel.

[0010] Another aspect of the present invention relates to a slurry fuel, which contains the biomass liquid fuel produced by the above-mentioned production method and wood biomass residue.

[0011] Another aspect of the present invention relates to a method for producing a slurry fuel, the method comprising the step of mixing the biomass liquid fuel produced by the above-mentioned production method with wood biomass residue.

[0012] Another aspect of the present invention relates to a method for recycling woody biomass, which uses, as a thermal energy source, a component of the decomposition gas that is not recovered as a biomass liquid fuel in the above-mentioned production method, or a woody biomass residue. Effect of the Invention

[0013] According to the present invention, there is provided a method for producing biomass liquid fuel that is capable of producing high-quality biomass liquid fuel with excellent handleability using woody biomass as a raw material. According to the present invention, there is also provided a slurry fuel using the biomass liquid fuel obtained by such a method for producing biomass liquid fuel and a method for producing the same. Furthermore, there is provided a method for converting woody biomass into a resource using such a method for producing biomass liquid fuel. [Brief description of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram showing a production apparatus used in the examples. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, embodiments of the present invention will be described in detail, however, the present invention is not limited to the following embodiments.

[0016] [Production method of biomass liquid fuel] A method for producing biomass liquid fuel in one embodiment includes a first step of heating woody biomass to 400 to 700° C. and separating it into a decomposition gas and a woody biomass residue, and a second step of cooling the decomposition gas to 0 to 100° C. and recovering the biomass liquid fuel. The heating time of the woody biomass in the first step is 1 to 40 minutes.

[0017] <First step> This step is a step in which woody biomass is heated to 400 to 700° C. and separated into decomposition gas and woody biomass residue.

[0018] Examples of woody biomass include construction waste wood, forest residues, sawmill residues, palm shells, rice husks, rice straw, wheat straw, feed, waste paper, and crushed materials thereof. Woody biomass may include crushed materials of at least one of construction waste wood and forest residues. Furthermore, crushed materials of construction waste wood may be crushed materials containing impurities such as metals, or may be crushed materials from which impurities have been removed.

[0019] The maximum particle size of the woody biomass may be 1.18 mm or more and less than 106 mm (75 mm or less). If the maximum particle size of the woody biomass is less than 1.18 mm, the proportion of components that scatter together with the decomposition gas increases, and the amount of the scattered components that are mixed into the biomass liquid fuel tends to increase. If the maximum particle size of the woody biomass is 106 mm or more, there are more areas of the woody biomass that are not sufficiently heated, and the production efficiency tends to decrease. In this specification, the maximum particle size of woody biomass means the numerical value of the mesh size of the metal mesh sieve that shows the smallest value among the metal mesh sieves through which 99.5% by mass or more of the entire woody biomass passes when the woody biomass is sieved in order through metal mesh sieves with nominal mesh sizes of 106 mm, 75 mm, 63 mm, 53 mm, 37.5 mm, 31.5 mm, 26.5 mm, 19 mm, 16 mm, 9.5 mm, 4.75 mm, 3.35 mm, 2.36 mm, 1.18 mm, and 600 μm as specified in JIS Z 8801-1. The maximum particle size of the woody biomass is preferably 2.36 mm or more and less than 26.5 mm (19 mm or less), more preferably 3.35 mm or more and less than 9.5 mm (4.75 mm or less).

[0020] The heating temperature of the woody biomass is 400 to 700°C. If the heating temperature of the woody biomass is less than 400°C, the woody biomass does not decompose sufficiently, and the yield of the biomass liquid fuel tends to decrease. If the heating temperature of the woody biomass exceeds 700°C, the decomposition of the woody biomass proceeds too much, and the components that are not recovered as the biomass liquid fuel increase, and the yield of the biomass liquid fuel tends to decrease. The heating temperature of the woody biomass is preferably 400°C to 700°C, more preferably 420°C to 650°C, and even more preferably 450°C to 550°C.

[0021] The heating time of the woody biomass is 1 to 40 minutes. If the heating time of the woody biomass is less than 1 minute, undecomposed woody biomass remains, and the yield of the biomass liquid fuel tends to decrease. If the heating time of the woody biomass exceeds 40 minutes, the decomposition of components with high calorific value in the woody biomass progresses, the yield of the biomass liquid fuel decreases, and the calorific value of the obtained biomass liquid fuel tends to decrease. The heating time of the woody biomass is preferably 3 to 30 minutes, more preferably 6 to 20 minutes, and further preferably 8 to 15 minutes.

[0022] The heating atmosphere for woody biomass may be a non-oxidizing atmosphere from the viewpoint of preventing combustion of decomposition gas. More specifically, the heating atmosphere for woody biomass may be an atmosphere having an oxygen volume concentration of 8% or less. The oxygen volume concentration is preferably 5% or less, more preferably 1% or less.

[0023] From the viewpoint of equipment costs, this step may be carried out in either a rotary kiln furnace, a stoker furnace, or a batch furnace.

[0024] <Second step> This step is a step of cooling the cracked gas separated in the first step to 0 to 100° C. and recovering a biomass liquid fuel.

[0025] The cooling temperature of the cracked gas is 0 to 100° C., preferably 30 to 100° C., more preferably 50 to 100° C., and further preferably 80 to 98° C. By setting the cooling temperature of the cracked gas within this range, it becomes possible to recover a high-quality biomass liquid fuel with a high calorific value.

[0026] This step is carried out in an apparatus capable of controlling the cooling temperature of the cracked gas. Examples of such an apparatus include a cooling tower, a scrubber, a cyclone, etc. In addition, such an apparatus may be equipped with a heat exchanger, a heat retaining device, an agitating device, etc., in order to suppress separation of the biomass liquid fuel.

[0027] In this manner, the biomass liquid fuel can be recovered. The recovered biomass liquid fuel is usually in a liquid state at 25° C., and therefore tends to be easy to handle.

[0028] The calorific value of the biomass liquid fuel may be, for example, 5.0 MJ / kg or more, preferably 8.0 MJ / kg or more, more preferably 10.0 MJ / kg or more, and even more preferably 12.0 MJ / kg or more. The upper limit of the calorific value of the biomass liquid fuel may be, for example, 30.0 MJ / kg or less. In this specification, the calorific value refers to a value measured by an adiabatic calorimeter (for example, a Monken type digital calorimeter (OSK200, manufactured by Ogawa Sampling Co., Ltd.)).

[0029] [Slurry fuel and its manufacturing method] The slurry fuel in one embodiment contains the biomass liquid fuel produced by the above-mentioned production method and wood biomass residue.

[0030] The content of the biomass liquid fuel may be 60 to 99 mass %, preferably 65 to 98 mass %, more preferably 70 to 97 mass %, and further preferably 80 to 95 mass %, based on the total mass of the slurry fuel.

[0031] The woody biomass residue is a heat-treated woody biomass and may be a carbonized product. The woody biomass residue may be pulverized as necessary and used as a pulverized product. The maximum particle size of the pulverized product may be, for example, 150 μm or less. The maximum particle size of the pulverized product means the numerical value of the mesh size of a metal mesh sieve that shows the smallest value among metal mesh sieves through which 99.5% by mass or more of the entire pulverized product passes. The pulverization is not particularly limited as long as it is a general pulverizer used for pulverizing carbides or coal, and examples thereof include a vibration mill, a jaw crusher, a roller mill, and a ball mill.

[0032] The content of the woody biomass residue may be 1 to 40 mass% based on the total mass of the slurry fuel, preferably 2 to 35 mass%, more preferably 3 to 30 mass%, and even more preferably 5 to 20 mass%. If the content of the woody biomass residue exceeds 40 mass%, it may be difficult to mix uniformly, and it may not be possible to form a slurry.

[0033] The calorific value of the slurry fuel may be, for example, 5.0 MJ / kg or more, preferably 8.0 MJ / kg or more, more preferably 10.0 MJ / kg or more, and even more preferably 12.0 MJ / kg or more. The upper limit of the calorific value of the biomass liquid fuel may be, for example, 30.0 MJ / kg or less.

[0034] The slurry fuel of this embodiment can be obtained by a production method including a step of mixing the biomass liquid fuel produced by the above-mentioned production method with woody biomass residue.

[0035] [How to recycle wood biomass] In one embodiment, the method for recycling wood biomass uses, as a thermal energy source, a component of the decomposition gas that is not recovered as a biomass liquid fuel in the above-described production method, or wood biomass residue.

[0036] In the above-mentioned method for producing biomass liquid fuel, the decomposition gas separated in the first step may contain components that are not recovered as biomass liquid fuel in the second step. These components that are not recovered as biomass liquid fuel can be recovered as combustible gas and used as a thermal energy source.

[0037] Woody biomass residues can be recovered as charcoal and used as a thermal energy source. EXAMPLES

[0038] The present invention will be specifically described below based on examples, but the present invention is not limited to these.

[0039] <Preparation of manufacturing equipment> Biomass liquid fuel was produced using the following production apparatus. FIG. 1 is a schematic diagram showing the production apparatus used in the examples. The production apparatus 100 shown in FIG. 1 includes a heating section 20, a first recovery section 10, and a second recovery section 60. The heating section 20 is mainly composed of a ceramic tube 22 and a tubular furnace 24. The ceramic tube 22 has therein a woody biomass 36 to be heated, a sample boat 34 for placing the woody biomass 36, and a wire 30 for moving the sample boat 34. The ceramic tube 22 also has a sample moving wire piping 32 for taking the wire 30 out to the outside, a gas introduction pipe 42 for introducing gas, a connecting pipe 44 for connecting to the first recovery section 10, and a sealing plug 26 for sealing the ceramic tube 22. The first recovery section 10 is mainly composed of a temperature regulator 12 and a recovery container 14. The first recovery section 10 has a connecting pipe 44 connected to the heating section 20 and a gas discharge pipe 46 connected to the second recovery section 60. The second recovery section 60 is for recovering components of the decomposition gas that are not recovered as biomass liquid fuel. The heating atmosphere can be adjusted by introducing a specified gas. The specified gas introduced during heating is introduced from the gas introduction pipe 42 into the ceramic tube 22, moves to the first recovery section 10 together with the decomposition gas of the woody biomass, and further moves to the second recovery section 60 together with the components of the decomposition gas that are not recovered as biomass liquid fuel.

[0040] <Production of biomass liquid fuel> Example 1 As woody biomass, 26 g of crushed construction waste wood (maximum particle size: 4.75 mm) dried to a moisture content of 10% or less was placed on a sample boat and placed at a point below 100°C at the end of the ceramic tube. Nitrogen gas was introduced into the ceramic tube by adjusting the flow rate (0.1 L / min) so that the residence time of the nitrogen gas at the heating point (inner diameter 6 cm x heating point length 30 cm) was 510 seconds. After that, the temperature of the first recovery section was set to 0°C, and the temperature of the tubular furnace was increased to 500°C. Next, the sample boat carrying the crushed construction waste wood was moved to the center of the tubular furnace and heated for 10 minutes to generate decomposition gas. The generated decomposition gas was cooled in the first recovery section to obtain the biomass liquid fuel of Example 1. The calorific value of the obtained biomass liquid fuel was measured using a Monken type digital calorimeter (OSK200, manufactured by Ogawa Sampling Co., Ltd.). The results are shown in Table 1.

[0041] (Examples 2 to 6 and Comparative Examples 1 and 2) Biomass liquid fuels of Examples 2 to 6 and Comparative Examples 1 and 2 were obtained in the same manner as in Example 1, except that the production conditions of Example 1 in Table 1 were changed to the production conditions of Examples 2 to 6 and Comparative Examples 1 and 2 in Table 1. The calorific values ​​of the biomass liquid fuels of Examples 2 to 6 and Comparative Examples 1 and 2 were measured in the same manner as in Example 1. The results are shown in Table 1.

[0042] [Table 1]

[0043] As shown in Table 1, the biomass liquid fuels of Examples 1 to 6 were liquid at 25° C. and had good handleability. In contrast, the biomass liquid fuels of Comparative Examples 1 and 2 were gel-like and had insufficient handleability.

[0044] Furthermore, when the woody biomass residues in Examples 1 and 2 were visually inspected, it was confirmed that the woody biomass was uniformly carbonized. On the other hand, when the woody biomass residue in Example 6 was inspected, it was confirmed that there were some areas that were not sufficiently heated and that the woody biomass remained.

[0045] In addition, a comparison between Example 1 and Example 2 revealed that the shorter the residence time of the nitrogen gas at the heating point, the higher the calorific value tends to be. Furthermore, a comparison between Example 2, Example 3, and Example 4 revealed that the higher the cooling temperature is within the range of 0 to 100°C, the higher the calorific value tends to be.

[0046] <Production of slurry fuel> (Examples 7 and 8 and Reference Example 1) The woody biomass residue in Example 2 was pulverized to 150 μm or less to obtain a pulverized product. The biomass liquid fuel of Example 2 and the pulverized product of the woody biomass residue were mixed in the blending ratio shown in Table 2 to obtain slurry fuels of Examples 7 and 8. The calorific values ​​of the slurry fuels of Examples 7 and 8 were measured in the same manner as in Example 1. The results are shown in Table 2. Table 2 also shows the calorific value of the biomass liquid fuel of Example 2 and the calorific value of the pulverized product of the woody biomass residue measured in the same manner as in Example 1.

[0047] [Table 2]

[0048] The slurry fuels of Examples 7 and 8 were found to have sufficient fluidity when visually observed, and as shown in Table 2, the slurry fuels of Examples 7 and 8 were found to have sufficiently high heating values. [Explanation of symbols]

[0049] 10...first recovery section, 12...temperature regulator, 14...recovery container, 20...heating section, 22...ceramic tube, 24...tubular furnace, 26...sealant plug, 30...wire, 32...wire piping for moving samples, 34...sample boat, 36...woody biomass, 42...gas inlet pipe, 44...connecting pipe, 46...gas exhaust pipe, 60...second recovery section, 100...manufacturing equipment.

Claims

1. A first step of heating woody biomass to 400 to 700°C and separating it into a decomposition gas and a woody biomass residue; A second step of cooling the decomposition gas to 90 to 100°C to recover biomass liquid fuel; Equipped with The heating time of the woody biomass in the first step is 1 to 40 minutes. A method for producing biomass liquid fuel.

2. The first step is carried out in either a rotary kiln furnace, a stoker furnace, or a batch furnace; The method for producing biomass liquid fuel according to claim 1 .

3. The maximum particle size of the woody biomass is 1.18 mm or more and less than 106 mm; The method for producing biomass liquid fuel according to claim 1 or 2.

4. The woody biomass includes at least one crushed material of construction waste wood and forest residues, The method for producing biomass liquid fuel according to any one of claims 1 to 3.

5. A biomass liquid fuel produced by the production method according to any one of claims 1 to 4 and the wood biomass residue are contained. Slurry fuel.

6. The method includes a step of mixing the biomass liquid fuel produced by the method according to any one of claims 1 to 4 with the wood biomass residue. A method for producing slurry fuel.

7. In the production method according to any one of claims 1 to 4, a component of the decomposition gas that is not recovered as the biomass liquid fuel or the wood biomass residue is used as a thermal energy source. Methods for turning wood biomass into resources.

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