Starting material charging device, synthesis gas generation system, and starting material charging method

Abstract

A starting material charging device 2 comprises a woody starting material charging unit 211 that charges a woody starting material that includes wood as principal component as a solid starting material into a gasification furnace 11 that gasifies solid starting materials to generate a synthesis gas that includes hydrogen and carbon monoxide, a plastic starting material charging unit 212 that charges a plastic starting material that includes plastic as a principal component as a solid starting material into the gasification furnace 11, and an H2 / CO ratio monitoring unit 22 that monitors the H2 / CO ratio of the synthesis gas generated by the gasification furnace 11. The plastic starting material charging unit 212 adjusts the amount of the plastic starting material that is charged into the gasification furnace 11 such that the H2 / CO ratio is at or above 2.

Description

Raw material input device, synthesis gas production system, raw material input method

[0001] This disclosure relates to a raw material feeding device for a gasification furnace, etc.

[0002] Patent Document 1 discloses a gasifier that gasifies the coal that is fed into it.

[0003] Japanese Patent Publication No. 2014-125503

[0004] Conventional gasifiers often used coal as a solid raw material, as shown in Patent Document 1. However, with the growing environmental awareness in recent years, biomass raw materials with a lower environmental impact are attracting attention as alternative solid raw materials. Biomass raw materials are typically wood-based raw materials such as wood pellets derived from wood. However, changing from coal to wood-based raw materials may alter the composition of synthesis gas and other substances produced by the gasifier.

[0005] This disclosure is made in view of these circumstances and aims to provide a raw material input device, etc., that can appropriately produce synthesis gas from woody raw materials using a gasification furnace.

[0006] To solve the above problems, a raw material feeding apparatus according to one aspect of the present disclosure includes a woody raw material feeding section for feeding woody raw materials, mainly composed of wood, as solid raw materials into a gasification furnace that gasifies solid raw materials to produce synthesis gas containing hydrogen and carbon monoxide, and a plastic raw material feeding section for feeding plastic raw materials, mainly composed of plastic, as solid raw materials into the gasification furnace.

[0007] According to this embodiment, by introducing plastic raw materials in addition to woody raw materials into the gasification furnace, synthesis gas can be appropriately produced (details will be described later).

[0008] Another aspect of the present disclosure is a synthesis gas production system. This synthesis gas production system comprises a gasifier that gasifies solid raw materials to produce synthesis gas containing hydrogen and carbon monoxide; a woody raw material input unit for inputting woody raw materials, mainly composed of wood, as solid raw materials into the gasifier; and a plastic raw material input unit for inputting plastic raw materials, mainly composed of plastic, as solid raw materials into the gasifier.

[0009] Another aspect of this disclosure is a method for feeding raw materials. This method involves feeding woody raw materials, mainly composed of wood, as solid raw materials into a gasifier that gasifies solid raw materials to produce synthesis gas containing hydrogen and carbon monoxide, and feeding plastic raw materials, mainly composed of plastic, as solid raw materials into the gasifier.

[0010] Furthermore, any combination of the above components, as well as any representations thereof converted into methods, apparatus, systems, recording media, computer programs, etc., are also included in this disclosure.

[0011] According to this disclosure, synthesis gas can be appropriately produced from woody raw materials using a gasification furnace.

[0012] A schematic diagram of the synthesis gas production system is shown. The changes in tar concentration and H2 / CO ratio according to the weight ratio of woody and plastic raw materials are also schematically shown.

[0013] The following describes in detail the forms for implementing this disclosure (hereinafter also referred to as embodiments) with reference to the drawings. In the description and / or drawings, identical or equivalent components, members, processes, etc., are denoted by the same reference numerals, and redundant descriptions are omitted. The scale and shape of the illustrated parts are set for convenience to simplify the description and are not to be interpreted restrictively unless otherwise specified. The embodiments are illustrative and do not limit the scope of this disclosure in any way. Not all features or combinations thereof presented in the embodiments are necessarily essential to this disclosure. For convenience, embodiments are presented by breaking them down into components for each function and / or group of functions that realize them. However, one component in an embodiment may actually be realized by a combination of multiple components as separate entities, and multiple components in an embodiment may actually be realized by a single component as a whole. Furthermore, multiple embodiments and modifications may be disclosed in parallel, and any components of each embodiment and / or modification may be combined in any manner as long as they do not interfere with each other's functions.

[0014] Figure 1 schematically shows the configuration of the synthesis gas production system 1 according to this embodiment. The synthesis gas production system 1 comprises a gasifier 11, a gas cooler 12, a filter 13, a tar decomposition unit 14, and a gas cooler 15. Some of these components may be omitted or modified, or other components may be added, as long as the synthesis gas production system 1 can achieve at least some of the operations and / or effects described below.

[0015] The gasifier 11 gasifies various raw materials introduced by the raw material input section 21, which will be described later, to produce synthesis gas containing hydrogen and carbon monoxide. The type of gasifier 11 is arbitrary, but the gasifier 11 in this embodiment is a fluidized bed type. This fluidized bed type gasifier 11 includes a hollow furnace body 111 extending in a substantially vertical direction (substantially up and down direction in Figure 1), a feeder 112 such as a conveyor that introduces various raw materials supplied from the raw material input section 21 into the lower part of the furnace body 111, and a cyclone 113 that separates and collects solid matter (unreacted raw materials, ash, dust, etc.) discharged from the upper part of the furnace body 111 from the synthesis gas and returns it to the furnace body 111.

[0016] In addition to the woody and plastic raw materials introduced by the raw material input section 21, the gasifier 11 may also be supplied with any gas that promotes gasification, such as oxygen, water vapor, carbon dioxide, or air (which may be supplied from the other raw material input section 213, as described later).

[0017] Furthermore, the gasifier 11 may be fed with a fluidizing agent or circulating agent such as silica sand or limestone. In the fluidized bed (not shown) formed at the bottom of the gasifier 11, a fluidizing agent in the form of powder, particulate matter, or lumps is flowing. Solid raw materials such as woody raw materials or plastic raw materials that are fed into this fluidized material are efficiently gasified by repeatedly coming into contact with the high-temperature fluidizing agent so as to be agitated within the fluidized bed.

[0018] The aforementioned cyclone 113 may separate and collect the fluidized material discharged from the top of the furnace body 111 from the synthesis gas and return it to the furnace body 111. Note that the gasification furnace 11 is not limited to the circulating fluidized bed (CFB) type described above; for example, a bubbling fluidized bed (BFB) type may also be used. In this case, since there is no need to circulate the fluidized material, the cyclone 113 may not be provided.

[0019] As will be described later, in this embodiment, various raw materials, including various woody raw materials and plastic raw materials, are introduced into the furnace body 111 at a high temperature (for example, 800°C to 1000°C) through the raw material input section 21 and the feeder 112. The woody raw materials and plastic raw materials contain carbon (C), hydrogen (H), oxygen (O), etc., and are gasified by heating and / or combustion in the furnace body 111, generating a gas containing hydrogen (H2), carbon monoxide (CO), and other molecules.

[0020] Thus, the gas produced by the gasifier 11 includes gases other than hydrogen (H2) and carbon monoxide (CO), which are the main components of synthesis gas. In this embodiment, these gases are also conveniently referred to as synthesis gas. The low-purity synthesis gas discharged from the gasifier 11 is purified by passing through the filter 13 and the tar decomposition unit 14, and is finally discharged from the synthesis gas production system 1.

[0021] The gas cooler 12 cools the synthesis gas discharged from the gasification furnace 11. The filter 13 separates and removes solid matter (unreacted raw materials, ash, dust, etc.) from the synthesis gas after it has passed through the gas cooler 12.

[0022] The tar decomposition unit 14 is a reformer or reformer that decomposes the tar contained in the synthesis gas produced by the gasification furnace 11 by catalytic partial oxidation (CPOX). The tar decomposition unit 14 comprises a hollow furnace body 141 extending in a substantially vertical direction (substantially up and down direction in Figure 1) and one or more catalyst members 142 arranged within the furnace body 141. As schematically shown in Figure 1, the catalyst members 142 may be plate-shaped members on which a catalyst is arranged on the surface, and if the furnace body 141 is substantially cylindrical, it is preferable that multiple catalyst members 142 are regularly arranged along at least one of the axial, radial, or circumferential directions.

[0023] As mentioned above, in a fluidized bed gasifier 11 operated at temperatures below 1000°C, tar is generated during the gasification of the raw materials. Tar is a viscous, dark brown liquid mainly composed of aromatic hydrocarbons such as toluene and naphthalene, and may also contain other organic compounds. In the tar decomposition section 14 using the CPOX method, the tar chemically reacts with air or water vapor on a catalyst (catalytic element 142) inside the furnace body 141 at a high temperature (e.g., 800°C to 900°C) and is decomposed into hydrogen and carbon monoxide. As a result, the purity of the synthesis gas is increased after passing through the tar decomposition section 14. In the example shown in Figure 1, low-purity synthesis gas containing tar is supplied from the gasifier 11 (and gas cooler 12, filter 13) to the top of the furnace body 141, and high-purity synthesis gas from which tar has been substantially removed is discharged from the bottom of the furnace body 141. However, the arrangement of the air intake and exhaust ports in the furnace body 141 is arbitrary.

[0024] The gas cooler 15 cools the high-purity synthesis gas discharged from the tar decomposition section 14. The high-purity synthesis gas that has passed through the gas cooler 15 is discharged outside the synthesis gas production system 1. Although not shown in the figures, a reaction section for various synthesis reactions or chemical reactions based on the synthesis gas, such as FT (Fischer Tropsch) synthesis (for example, for the production of SAF (Sustainable Aviation Fuel)), methanol synthesis, and ethanol synthesis, may be provided downstream of the synthesis gas production system 1.

[0025] The raw material input device 2 according to this embodiment includes a raw material input unit 21, an H2 / CO ratio monitoring unit 22, a notification unit 23, and a tar concentration monitoring unit 24. Some of these functional blocks may be omitted or modified, or other functional blocks may be added, as long as the raw material input device 2 can achieve at least some of the operations and / or effects described below. These functional blocks may be realized through the cooperation of hardware resources such as the central processing unit, memory, input devices, output devices, and peripheral devices connected to the computer, and software that runs using them. Regardless of the type or location of the computer, each of the above functional blocks may be realized with the hardware resources of a single computer, or it may be realized by combining hardware resources distributed across multiple computers.

[0026] The raw material input unit 21 inputs various raw materials, including solid raw materials, into the gasification furnace 11 (furnace body 111). In this embodiment, the raw material input unit 21 may include a wood raw material input unit 211, a plastic raw material input unit 212, and an other raw material input unit 213. The wood raw material input unit 211 inputs wood raw materials, mainly composed of wood, as solid raw materials into the gasification furnace 11. The plastic raw material input unit 212 inputs plastic raw materials, mainly composed of plastic, as solid raw materials into the gasification furnace 11.

[0027] The other raw material input section 213 may input solid raw materials different from woody raw materials and plastic raw materials to the gasifier 11, or it may input any liquid or gaseous raw materials to promote gasification in the gasifier 11. However, as will be described later, this embodiment has the advantage that the synthesis gas generation system 1 can be properly operated with only the woody raw material input section 211 and the plastic raw material input section 212, even without the other raw material input section 213. For this reason, in the following exemplary description, the other raw material input section 213 will not be provided.

[0028] The woody raw material input section 211 and the plastic raw material input section 212 (and, if provided, the other raw material input section 213) may, as schematically shown in Figure 1, input their respective raw materials into the furnace body 111 of the gasifier 11 through a common raw material input mechanism or raw material input port such as a feeder 112, or they may input their respective raw materials into the furnace body 111 of the gasifier 11 through individual raw material input mechanisms or raw material input ports (not shown).

[0029] The woody raw material supplied by the woody raw material input unit 211 is mainly composed of wood. Specifically, it is preferable that 50% or more of the woody raw material is derived from wood, 70% or more of the woody raw material is derived from wood, and it is even more preferable that 90% or more of the woody raw material is derived from wood. The wood-derived components that make up the main part of such woody raw material are typically composed of about 40% cellulose, about 30% hemicellulose, about 25% lignin, and about 5% ash (totaling 100%).

[0030] The chemical formula for cellulose is C6H 12 The chemical formula for hemicellulose is "C6H 10 It is "O5" and has an H / C ratio of 5 / 3 (less than 2). The chemical formula for lignin is "C9H 10 O2(OCH3) n Assuming n ≈ 1, the H / C ratio is approximately 6 / 5 (less than 2). Thus, since woody raw materials contain a significant proportion of hemicellulose and lignin, which have an H / C ratio less than 2, the average H / C ratio is significantly less than 2.

[0031] As described above, it was found that when only woody raw materials with a relatively low H / C ratio are fed into the gasifier 11 for gasification, the H2 / CO ratio, which is the ratio of the amount of substance or volume of hydrogen (H2) to carbon monoxide (CO) in the synthesis gas produced, becomes low. In an actual experiment using the H2 / CO ratio monitoring unit 22 described later, the H2 / CO ratio in the synthesis gas before tar decomposition by the tar decomposition unit 14 was about 1.4-1.6, and the H2 / CO ratio in the synthesis gas after tar decomposition by the tar decomposition unit 14 was about 1.6-1.8.

[0032] Even cellulose, which has the highest H / C ratio among the typical components of woody raw materials, has an H / C ratio of 2. Even if all the H is converted to hydrogen (H2) and all the C is converted to carbon monoxide (CO), the H2 / CO ratio is only 1. However, in the gasification furnace 11 and / or tar decomposition section 14, the following shift reaction and / or steam reforming reaction occur due to the steam (H2O) supplied to the interior, thus increasing the H2 / CO ratio above 1. However, as shown in the experimental results above, the H2 / CO ratio obtained from woody raw materials alone was less than 2. Shift reaction: CO + H2O → H2 + CO2 Steam reforming reaction: C n H m + nH2O → nCO + (m / 2+n)H2

[0033] Thus, using only woody raw materials results in an H2 / CO ratio in the synthesis gas ultimately produced by the synthesis gas generation system 1 that is significantly lower than 2. As mentioned above, in catalytic synthesis reaction sections such as FT synthesis, methanol synthesis, and ethanol synthesis that can be provided downstream of the synthesis gas generation system 1, an H2 / CO ratio of 2 or higher can be obtained according to the following chemical reaction equations.

[0034] FT synthesis: (2n+1)H2 + nCO → C n H 2n+2 Methanol synthesis: CO₂ + 2H₂ → CH₃OH Required H₂ / CO ratio = (2n+1) / n ≈ 2 Ethanol synthesis: 2CO₂ + 4H₂ → C₂H₅OH + H₂O Required H₂ / CO ratio = 2

[0035] As described above, woody raw materials alone cannot achieve the H2 / CO ratio of 2 or more required for catalytic synthesis reactions such as FT synthesis, methanol synthesis, and ethanol synthesis, and therefore the synthesis gas production system 1 cannot be operated properly. While it is conceivable to supply additional hydrogen from an external source or install an additional shift reactor to produce hydrogen in order to achieve an H2 / CO ratio of 2 or more, this would lead to an increase in CAPEX and OPEX, potentially worsening the profitability or economic viability of the synthesis gas production system 1.

[0036] Therefore, in this embodiment, plastic raw materials to supplement the woody raw materials are introduced into the gasification furnace 11 by the plastic raw material input unit 212.

[0037] The plastic raw material supplied by the plastic raw material input unit 212 mainly consists of plastic or synthetic resin. Specifically, it is preferable that 50% or more of the plastic raw material is plastic, preferably 70% or more is plastic, and more preferably 90% or more is plastic. Typical plastics include polyethylene and polypropylene.

[0038] The structural formula of polyethylene is "(-CH2-)", and the H / C ratio of H (hydrogen) to C (carbon) is 2. The structural formula of polypropylene is "(-CH(CH3)-CH2-)", and the H / C ratio of H (hydrogen) to C (carbon) is 2. Thus, the H / C ratio of plastic raw materials is relatively high, around 2. As mentioned above, the H / C ratio of woody raw materials was significantly lower than 2 due to hemicellulose and lignin.

[0039] As described above, it was found that by adding a plastic raw material with a relatively high H / C ratio to a woody raw material and feeding it into the gasification furnace 11 for gasification, the H2 / CO ratio, which is the ratio of the amount of substance or volume of hydrogen (H2) to carbon monoxide (CO) in the synthesis gas produced, can be increased. In an actual experiment using the H2 / CO ratio monitoring unit 22 described later, the H2 / CO ratio in the synthesis gas before tar decomposition by the tar decomposition unit 14 was about 2.5, and the H2 / CO ratio in the synthesis gas after tar decomposition by the tar decomposition unit 14 was about 2.6.

[0040] Thus, by adding a plastic raw material to a woody raw material, the synthesis gas generation system 1 can appropriately generate a high H2 / CO ratio synthesis gas for catalytic synthesis reactions such as Fischer-Tropsch synthesis, methanol synthesis, ethanol synthesis, etc., which require a H2 / CO ratio of 2 or more. Here, the plastic raw material may be a waste plastic raw material derived from discarded plastic products, plastic waste generated during its manufacturing process, etc. Since the waste plastic raw material is inexpensive and may be procured at a reverse charge in some cases, the profitability of the synthesis gas generation system 1 can be significantly enhanced.

[0041] The mode and order in which the woody raw material input section 211 and the plastic raw material input section 212 input their respective raw materials into the gasification furnace 11 are arbitrary. For example, the woody raw material input section 211 and the plastic raw material input section 212 may input their respective raw materials into the gasification furnace 11 simultaneously. At this time, in a state where the woody raw material and the plastic raw material are mixed, they may be input into the furnace body 111 of the gasification furnace 11 through a common feeder 112. Also, the woody raw material and the plastic raw material may be input simultaneously through different raw material inlets (not shown).

[0042] Alternatively, the plastic raw material input section 212 may additionally input a plastic raw material into the gasification furnace 11 into which the woody raw material has been input by the woody raw material input section 211, or the woody raw material input section 211 may additionally input a woody raw material into the gasification furnace 11 into which the plastic raw material has been input by the plastic raw material input section 212.

[0043] The H2 / CO ratio monitoring unit 22 monitors the H2 / CO ratio of hydrogen and carbon monoxide in the synthesis gas generated by the gasification furnace 11. The H2 / CO ratio monitoring unit 22 may measure the H2 / CO ratio in the synthesis gas generated by the gasification furnace 11 and before tar decomposition by the tar decomposition unit 14 (for example, the unmodified synthesis gas discharged from the filter 13 as illustrated in FIG. 1), or may measure the H2 / CO ratio in the synthesis gas generated by the gasification furnace 11 and after tar decomposition by the tar decomposition unit 14 (for example, the modified synthesis gas discharged from the gas cooler 15 as illustrated in FIG. 1, which is the synthesis gas finally discharged from the synthesis gas generation system 1). Thus, it is preferable that the H2 / CO ratio monitoring unit 22 monitors the H2 / CO ratio in the synthesis gas at preferably a plurality of positions downstream of the gasification furnace 11.

[0044] The plastic raw material input unit 212 preferably automatically adjusts the input amount of the plastic raw material to the gasification furnace 11 so that the H2 / CO ratio monitored by the H2 / CO ratio monitoring unit 22 becomes 2 or more. As described above, when a catalytic synthesis reaction unit such as FT synthesis, methanol synthesis, or ethanol synthesis is provided downstream of the synthesis gas generation system 1, it is preferable to increase the H2 / CO ratio in the synthesis gas as the final output of the synthesis gas generation system 1 to 2 or more. For this reason, the plastic raw material input unit 212 automatically adjusts the input amount of the plastic raw material to the gasification furnace 11 so that, for example, the H2 / CO ratio of the synthesis gas (final output) discharged from the gas cooler 15 monitored by the H2 / CO ratio monitoring unit 22 becomes 2 or more.

[0045] As mentioned above, the H2 / CO ratio can be increased by increasing the amount of plastic raw material input. Conversely, if the H2 / CO ratio monitored by the H2 / CO ratio monitoring unit 22 is significantly higher than 2 (for example, 2.5 or higher, or 3.0 or higher), the plastic raw material input unit 212 may automatically reduce the amount of plastic raw material input to the gasifier 11. The plastic raw material input unit 212 may also automatically adjust the amount of plastic raw material input to the gasifier 11 so that the H2 / CO ratio in the synthesis gas before tar decomposition by the tar decomposition unit 14 is 2 or higher, so that the H2 / CO ratio of the synthesis gas as the final output of the synthesis gas generation system 1 is reliably 2 or higher. As shown in the example above, the H2 / CO ratio usually increases after passing through the tar decomposition unit 14, so if the H2 / CO ratio is 2 or higher before the tar decomposition unit 14, it will almost certainly be 2 or higher after the tar decomposition unit 14.

[0046] Similarly, the woody raw material input unit 211 may automatically adjust the amount of woody raw material input to the gasifier 11 so that the H2 / CO ratio monitored by the H2 / CO ratio monitoring unit 22 is 2 or higher. For example, the woody raw material input unit 211 may automatically adjust the amount of woody raw material input to the gasifier 11 so that the H2 / CO ratio of the synthesis gas (final output) discharged from the gas cooler 15, monitored by the H2 / CO ratio monitoring unit 22, is 2 or higher. Reducing the amount of woody raw material input can increase the H2 / CO ratio. Conversely, if the H2 / CO ratio monitored by the H2 / CO ratio monitoring unit 22 is significantly higher than 2 (for example, 2.5 or higher, or 3.0 or higher), the woody raw material input unit 211 may automatically increase the amount of woody raw material input to the gasifier 11. Furthermore, the woody raw material input unit 211 may automatically adjust the amount of woody raw material input to the gasifier 11 so that the H2 / CO ratio in the synthesis gas before tar decomposition by the tar decomposition unit 14 is 2 or more, so that the H2 / CO ratio in the synthesis gas before tar decomposition by the tar decomposition unit 14 is 2 or more, so that the H2 / CO ratio of the synthesis gas as the final output of the synthesis gas generation system 1 is reliably 2 or more.

[0047] As described above, under the monitoring of the H2 / CO ratio monitoring unit 22, the automatic adjustment of the amount of plastic raw material input by the plastic raw material input unit 212 and the automatic adjustment of the amount of wood raw material input by the wood raw material input unit 211 may be performed individually or in appropriate combination according to a predetermined logic or algorithm. Furthermore, as long as the desired H2 / CO ratio (range) of the synthesis gas as the final output of the synthesis gas generation system 1 is achieved, the amount of other raw materials input by the other raw material input unit 213 may be automatically adjusted.

[0048] The adjustment of the amount of plastic raw material input by the plastic raw material input unit 212, and / or the adjustment of the amount of wood raw material input by the wood raw material input unit 211, may be performed manually by the operator of the synthesis gas generation system 1. For this purpose, it is preferable that real-time monitoring data of the H2 / CO ratio of the synthesis gas in each part of the synthesis gas generation system 1 (especially the final output unit) by the H2 / CO ratio monitoring unit 22 is displayed on a monitor such as a computer 3 that can be viewed by the operator or other user.

[0049] Furthermore, the notification unit 23 may notify the user, by any means such as display on a monitor such as a computer 3, sound, light, vibration, or message, that the H2 / CO ratio being monitored by the H2 / CO ratio monitoring unit 22 is less than 2. Upon receiving the notification, the user can quickly take action to restore the H2 / CO ratio of the synthesis gas to 2 or more (for example, increasing the amount of plastic raw material input by the plastic raw material input unit 212).

[0050] The tar concentration monitoring unit 24 monitors the concentration of tar contained in the synthesis gas before tar decomposition by the tar decomposition unit 14 (for example, the unmodified synthesis gas discharged from the filter 13, as illustrated in Figure 1). As mentioned above, the tar decomposition unit 14 typically decomposes tar by chemical reactions occurring on a number of catalyst members 142, but if the tar concentration is too high, the catalyst members 142 may be covered with tar, and the chemical reaction may not proceed properly. Therefore, in this embodiment, the amount of various raw materials input by the raw material input unit 21 may be adjusted so that the tar concentration remains within an appropriate range.

[0051] Figure 2 schematically shows changes in the tar concentration (the one immediately before the tar decomposition unit 14 measured by the tar concentration monitoring unit 24) and the H2 / CO ratio (the one immediately after the gas cooler 15 measured by the H2 / CO ratio monitoring unit 22) according to the weight ratio (wt%) of the input amounts of the woody raw material (illustrated as "woody") by the woody raw material input unit 211 and the plastic raw material (illustrated as "waste plastic") by the plastic raw material input unit 212.

[0052] As described above, when the ratio of the woody raw material to the plastic raw material is increased (shift to the right in FIG. 2), the H2 / CO ratio decreases. In the example of the present embodiment, since it is desired to secure an H2 / CO ratio of 2 or more, it is preferable to set the ratio of the woody raw material to the plastic raw material to about 70% or less (the ratio of the plastic raw material to about 30% or more).

[0053] On the other hand, when the ratio of the plastic raw material to the woody raw material is increased (shift to the left in FIG. 2), the tar concentration increases. In the example of the present embodiment, when the tar concentration exceeds an upper limit value of about 80,000 - 100,000 [mg / Nm 3 , it may interfere with the normal continuous operation of the tar decomposition unit 14. Therefore, it is preferable to set the ratio of the plastic raw material to the woody raw material to about 70% - 75% or less (the ratio of the woody raw material to about 25% - 30% or more) so that the tar concentration does not exceed the upper limit value.

[0054] As described above, in a typical example assumed in the present embodiment, by setting the ratio of the plastic raw material to the woody raw material to 30% or more and 70% - 75% or less, it is possible to achieve both securing an H2 / CO ratio of 2 or more and normal continuous operation of the tar decomposition unit 14.

[0055] As described above, the plastic raw material input unit 212 preferably automatically adjusts the input amount of the plastic raw material to the gasifier 11 so that the H2 / CO ratio monitored by the H2 / CO ratio monitoring unit 22 becomes 2 or more and the tar concentration monitored by the tar concentration monitoring unit 24 falls within the normal operating range of the tar decomposition unit 14.

[0056] As shown in Figure 2, reducing the amount of plastic raw material input can lower the tar concentration. Conversely, if the tar concentration monitored by the tar concentration monitoring unit 24 is significantly lower than the processing capacity of the tar decomposition unit 14, the plastic raw material input unit 212 may automatically increase the amount of plastic raw material input to the gasification furnace 11.

[0057] Similarly, the woody raw material input unit 211 may automatically adjust the amount of woody raw material input to the gasifier 11 so that the H2 / CO ratio monitored by the H2 / CO ratio monitoring unit 22 is 2 or more, and the tar concentration monitored by the tar concentration monitoring unit 24 falls within the normal operating range of the tar decomposition unit 14.

[0058] As shown in Figure 2, increasing the amount of woody raw material input can lower the tar concentration. Conversely, if the tar concentration monitored by the tar concentration monitoring unit 24 is significantly lower than the processing capacity of the tar decomposition unit 14, the woody raw material input unit 211 may automatically reduce the amount of woody raw material input to the gasification furnace 11.

[0059] As described above, under the monitoring of the tar concentration monitoring unit 24, the automatic adjustment of the amount of plastic raw material input by the plastic raw material input unit 212 and the automatic adjustment of the amount of wood raw material input by the wood raw material input unit 211 may be performed individually or in combination as appropriate according to a predetermined logic or algorithm. Furthermore, as long as the tar concentration immediately before the tar decomposition unit 14 remains within the normal operating range of the tar decomposition unit 14, the amount of other raw materials input by the other raw material input unit 213 may be automatically adjusted.

[0060] The adjustment of the amount of plastic raw material input by the plastic raw material input unit 212 and / or the amount of wood raw material input by the wood raw material input unit 211 to control the tar concentration may be performed manually by the operator of the synthesis gas generation system 1. For this purpose, it is preferable that real-time monitoring data of the tar concentration by the tar concentration monitoring unit 24 is displayed on a monitor such as a computer 3 that can be viewed by the operator or other user.

[0061] Furthermore, the notification unit 23 may notify the user by any means such as a display on a monitor such as a computer 3, sound, light, vibration, or message if the tar concentration being monitored by the tar concentration monitoring unit 24 has fallen outside the normal operating range of the tar decomposition unit 14 (in particular, has exceeded the upper limit). Upon receiving the notification, the user can quickly take action to return the tar concentration to the normal operating range of the tar decomposition unit 14 (for example, by reducing the amount of plastic raw material input by the plastic raw material input unit 212).

[0062] The present disclosure has been described above based on embodiments. Various modifications are possible for each component and each combination of processes in the exemplary embodiments, and it will be obvious to those skilled in the art that such modifications are included in the scope of the present disclosure.

[0063] The configuration, operation, and function of each device and method described in the embodiments can be realized by hardware resources or software resources, or by the cooperation of hardware resources and software resources. Hardware resources include, for example, processors, ROMs, RAMs, and various integrated circuits. Software resources include, for example, operating systems and application programs.

[0064] This disclosure relates to a raw material feeding device for a gasification furnace, etc.

[0065] 1 Synthesis gas generation system, 2 Raw material input device, 11 Gasification furnace, 14 Tar decomposition unit, 21 Raw material input unit, 22 H2 / CO ratio monitoring unit, 23 Notification unit, 24 Tar concentration monitoring unit, 211 Wood raw material input unit, 212 Plastic raw material input unit, 213 Other raw material input unit.

Claims

1. A raw material feeding device comprising: a wood raw material feeding section for feeding wood raw materials, mainly composed of wood, as the solid raw material into a gasification furnace that gasifies solid raw materials to produce synthesis gas containing hydrogen and carbon monoxide; and a plastic raw material feeding section for feeding plastic raw materials, mainly composed of plastic, as the solid raw material into the gasification furnace.

2. The raw material feeding device according to claim 1, further comprising an H2 / CO ratio monitoring unit for monitoring the H2 / CO ratio of hydrogen to carbon monoxide in the synthesis gas produced by the gasification furnace, wherein the plastic raw material feeding unit adjusts the amount of plastic raw material fed into the gasification furnace so that the H2 / CO ratio is 2 or more.

3. The raw material feeding apparatus according to claim 1, comprising: an H2 / CO ratio monitoring unit for monitoring the H2 / CO ratio of hydrogen to carbon monoxide in the synthesis gas produced by the gasification furnace; and a notification unit for notifying that the H2 / CO ratio is less than 2.

4. The raw material feeding apparatus according to any one of claims 1 to 3, wherein the wood raw material feeding section and the plastic raw material feeding section are capable of simultaneously feeding the wood raw material and the plastic raw material into the gasification furnace.

5. The raw material feeding device according to any one of claims 1 to 3, wherein the plastic raw material feeding section is capable of additionally feeding the plastic raw material into the gasification furnace into which the woody raw material has been fed.

6. The raw material feeding apparatus according to any one of claims 1 to 3, wherein the plastic raw material is waste plastic raw material.

7. A synthesis gas generation system comprising: a gasification furnace that gasifies solid raw materials to produce synthesis gas containing hydrogen and carbon monoxide; a woody raw material input unit for inputting woody raw materials mainly composed of wood as the solid raw material into the gasification furnace; and a plastic raw material input unit for inputting plastic raw materials mainly composed of plastic as the solid raw material into the gasification furnace.

8. The synthesis gas production system according to claim 7, further comprising a tar decomposition unit that decomposes tar contained in the synthesis gas produced by the gasification furnace by a catalytic partial oxidation method.

9. A method for feeding raw materials into a gasification furnace that gasifies solid raw materials to produce synthesis gas containing hydrogen and carbon monoxide, comprising: feeding wood-based raw materials, mainly composed of wood, as the solid raw material; and feeding plastic raw materials, mainly composed of plastic, as the solid raw material into the gasification furnace.

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