Fuel production system for high-moisture-content material such as sewage sludge

Abstract

To provide a fuel production system capable of rapidly drying a high-moisture-content material such as sludge, reducing CO2 emissions, and obtaining fuel with a high calorific value.SOLUTION: A fuel production system 1 for drying a water-containing raw material M1 such as sludge comprises: a heat source device 10 that uses biomass fuel; a carbonization device 20 that carbonizes a carbonization raw material M2 by using hot air; and a drying device 40 that dries the water-containing raw material M1. Carbide C from the carbonization device 20 can be used in a pellet burner 13 or thermal power generation. By drying the water-containing raw material M1 such as sludge or livestock feces, performing carbonization treatment to produce fuel, and operating the fuel production system 1, the supply of fossil fuel is minimized, enabling continuous operation.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a system for drying substances with a high water content such as sludge and converting them into fuel.

Background Art

[0002] Substances with a high water content such as sludge have conventionally been mainly treated by dehydration and incineration, which required a large amount of fossil fuels for dehydration and incineration. For example, just looking at the dehydration process, a large amount of A heavy oil is used during the treatment. To dry 1 ton of sewage sludge with a water content of 80%, about 87.7 L of A heavy oil is required.

[0003] Here, the CO2 emission per liter of A heavy oil is about 2.71 kg. When drying 1 ton of sewage sludge, about 237.7 kg of CO2 will be emitted. This is just the A heavy oil required to simply dry the sewage sludge, and the A heavy oil required for incineration is additionally needed.

[0004] Thus, the treatment of substances with a high water content such as sludge requires a large amount of fossil fuels and incurs high costs. In addition, since the CO2 emissions also increase due to such treatment, means for reducing CO2 emissions are necessary as efforts towards SDGs.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Patent Document 1 discloses a sewage sludge fuelization system that dries and incinerates dewatered sewage sludge obtained by dewatering sewage sludge, and produces dried sludge that can be used as a biomass fuel such as in a biomass boiler. The sewage sludge fuelization system described in Patent Document 1 uses a biomass boiler that burns biomass fuel, and by supplying the dried sludge dried by a dryer to the biomass burner, it is stated that the CO2 emissions can be reduced. It is also described that the dried sludge can be used as a biomass fuel.

[0007] In Patent Document 1, it is described that dried sludge is used as a biomass fuel. However, the calorific value per unit mass of dried sludge is about 4,000 kcal / kg (about 16.8 MJ / kg) (paragraph 0035), and it is not possible to obtain a fuel with a high calorific value such as that of a fuel (6,000 kcal or more: about 25.2 MJ / kg) used in thermal power generation etc.

[0008] An object of the present invention is to provide a fuelization system that can rapidly dry substances with a high water content such as sludge, reduce CO2 emissions, and further obtain a fuel with a high calorific value.

Means for Solving the Problems

[0009] To achieve the above object, the fuel conversion system of the present invention is a fuel conversion system that dries and carbonizes a water-containing raw material to produce fuel, comprising a heat source device that generates hot air using biomass fuel, a drying device that dries the water-containing raw material using the hot air, and a carbonization device that carbonizes a carbonization raw material using the hot air. The drying device is a device that performs drying by directly contacting the water-containing raw material with the hot air, the carbonization device is an indirect heating type device that indirectly heats the carbonization raw material, the heat source device and the carbonization device, and the carbonization device and the drying device are sequentially connected by a hot air duct, the carbonization device is heated by the hot air from the heat source device, the hot air that has heated the carbonization device is introduced into the drying device to perform a drying process, the dried raw material dried by the drying device is input into the carbonization device, and the carbonization device generates carbide as fuel.

[0010] According to the fuel conversion system of the present invention, hot air is generated using biomass fuel by the heat source device, and carbonization by the carbonization device and drying by the drying device are performed with the hot air. Thereby, the amount of CO2 emissions can be reduced compared to the case of using fossil fuel. Also, not only drying by the drying device is performed, but also carbonization by the carbonization device is performed. The dried raw material dried by the drying device has a calorific value of about 16.8 MJ / kg in the case of sludge, for example, as described above. If this is carbonized in the carbonization device as a carbonization raw material, the final carbide can obtain a fuel having a calorific value equivalent to that of a fuel used for thermal power generation or the like.

[0011] Further, in the fuel conversion system of the present invention, the biomass fuel may be the carbide carbonized by the carbonization device. According to this configuration, carbide, which is a high-quality fuel, can be obtained from a water-containing raw material such as sludge, and since the carbide is used as biomass fuel, sludge and the like can be converted into fuel with minimal use of fossil fuel.

[0012] Further, in the fuel conversion system of the present invention, the carbonization device includes an outer chamber and a heating chamber held at a distance inside the outer chamber. The heating chamber includes a carbonization inlet into which the carbonization raw material is introduced, conveying means provided inside the heating chamber for conveying the carbonization raw material introduced into the heating chamber to the downstream side, and a carbonization discharge port provided on the downstream side of the heating chamber. A heating passage is formed between the outer chamber and the heating chamber, and the heating chamber may be indirectly heated by supplying the hot air from the heat source device to the heating passage.

[0013] According to this configuration, since the hot air is supplied to the heating passage to indirectly heat the heating chamber, the temperature drop of the hot air passing through this heating device is suppressed, and the temperature of the hot air supplied to the drying device can be kept high.

[0014] Further, in the fuel conversion system of the present invention, the drying device includes a dryer main body having a cylindrical space inside, stirring means that rotates around a rotating shaft provided along the axial direction of the dryer main body inside the dryer main body for stirring the water-containing raw material supplied into the dryer main body, a hot air supply port provided on the upstream side of the dryer main body to which the hot air is supplied, a drying inlet provided on the upstream side of the dryer main body into which the water-containing raw material is introduced, a drying discharge port provided on the downstream side of the dryer main body, and an exhaust port provided on the downstream side of the dryer main body. The dried raw material dried by the drying device may include that discharged from the drying discharge port and that separated from the exhaust gas discharged from the exhaust port and then discharged.

[0015] According to this configuration, the water-containing raw material introduced into the dryer main body is stirred by the stirring means in the dryer main body and directly exposed to the hot air, so that it can be dried quickly. Further, the dried raw material is discharged from the drying discharge port, and what floats in the dryer main body by the stirring means is separated from the exhaust gas after being discharged from the exhaust port and then discharged.

[0016] Further, in the fuel conversion system of the present invention, the hot air duct includes a first hot air duct connecting the heat source device and the carbonization device, and a second hot air duct connecting the carbonization device and the drying device. An adjustment damper for adjusting the amount of hot air supplied from the carbonization device to the drying device may be provided in the second hot air duct.

[0017] According to this configuration, since the flow rate of the hot air flowing into the drying device can be adjusted, the drying state of the drying device can be adjusted. Further, according to this configuration, even when the drying device cannot operate for some reason such as during maintenance, if the hot air is not supplied from the carbonization device to the drying device by the adjustment damper, the carbonization device can be operated alone.

[0018] Further, the fuel conversion system of the present invention may further include a gas engine using gas as fuel, an exhaust heat supply means for supplying exhaust heat gas including the exhaust gas of the gas engine to the drying device, and a power generation device driven by the gas engine. The gas engine is driven using the combustible gas generated when the carbonization raw material is heated in the carbonization device, power generation is performed by the power generation device, and the exhaust heat gas is supplied to the drying device by the exhaust heat supply means to perform a drying process by the drying device.

[0019] According to this configuration, since the gas engine can be driven using the combustible gas generated from the carbonization device, it is possible to utilize the power of the gas engine. For example, power generation can be performed by driving a generator with a gas engine. Further, the efficiency of the drying process of the drying device can be improved by the exhaust heat gas of the gas engine.

[0020] Further, in this configuration, the water-containing raw material is dried by the drying device to generate the dried raw material, the dried raw material is carbonized by the carbonization device to generate the carbide, the carbide is used as the biomass fuel by the heat source device to generate the hot air, and in a state where any one or all of the drying device, the carbonization device, or the heat source device is operated using the electric power generated by the power generation device, it is preferable that the amount of the carbide used per unit time in the heat source device is less than the amount of the carbide generated per unit time by the carbonization device.

[0021] According to this configuration, by simply supplying a water-containing raw material such as sludge to the fuel conversion system of the present invention, the entire system can be operated without replenishing fossil fuel from the outside. Further, since each device can be operated with the electric power generated by the power generation device, it is possible to eliminate the need for supplying electric power from the outside.

Effects of the Invention

[0022] According to the present invention, a substance with a high water content such as sludge can be rapidly dried, the amount of CO2 emissions can be reduced, and a fuel with a high calorific value can be obtained. Further, by providing a power generation device, electric power can also be obtained.

Brief Description of the Drawings

[0023]

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0024] Next, a fuel conversion system 1, which is an example of an embodiment of the present invention, will be described with reference to FIGS. 1 to 3. As shown in FIG. 1, the fuel conversion system 1 is a system that dries and carbonizes a water-containing raw material M1 to obtain a carbide C as fuel, and includes a heat source device 10 that generates hot air using biomass fuel B, a carbonization device 20 that carbonizes a carbonization raw material M2 using the hot air to obtain a carbide C, and a drying device 40 that dries the water-containing raw material M1 using the hot air. In FIGS. 1 to 3, the internal structure of each component is visualized and displayed as necessary.

[0025] The heat source device 10 and the carbonization device 20 are connected by a first hot air duct 11, and the carbonization device 20 and the drying device 40 are connected by a second hot air duct 12. These first hot air duct 11 and second hot air duct 12 constitute the hot air duct in the present invention. In the present embodiment, the heat source device 10, the carbonization device 20, and the drying device 40 are sequentially connected by hot air ducts.

[0026] In the present embodiment, the heat source device 10 uses a pellet burner 13 that burns pellet-shaped biomass fuel B as fuel. Further, in the present embodiment, the carbide C described later can be used as the biomass fuel B. The pellet burner 13 is a burner that burns pellet-shaped fuel to generate a heat source, and in the present embodiment, commercially available equipment is used. Further, as shown in FIG. 2, the heat source device 10 includes a fuel supply port 14 that supplies biomass fuel B, a cylindrical combustion chamber 15 in which combustion is performed by the pellet burner 13, and a cylindrical secondary combustion chamber 16 disposed so as to be orthogonal to the combustion chamber 15.

[0027] In this embodiment, the carbonization device 20 uses an indirectly heated rotary kiln. Specifically, the carbonization device 20 is an indirectly heated device that indirectly heats the carbonization raw material M2, and includes a fixed outer chamber 21 fixed to the installation surface and a rotary heating chamber 22 held at a distance inside the outer chamber 21. The heating chamber 22 includes a carbonization inlet 23 into which the carbonization raw material M2 is charged, a conveying means 24 provided in the heating chamber 22 for conveying the carbonization raw material M2 charged therein to the downstream side, a carbonization discharge port 25 provided on the downstream side of the heating chamber 22, and a carbide cooler 26 for cooling the carbide C discharged from the carbonization discharge port 25.

[0028] A heating passage 27 is formed between the outer chamber 21 and the heating chamber 22 of the carbonization device 20, and the outer chamber 21 is provided with a hot air supply port 28 to which the first hot air duct 11 is connected and a hot air outlet 29 to which the second hot air duct 12 is connected.

[0029] The carbonization device 20 is a device that indirectly heats the inside of the heating chamber 22 by supplying hot air from the heat source device 10 to the heating passage 27 through the first hot air duct 11 and the hot air supply port 28. The carbide C carbonized by this carbonization device 20 and discharged from the carbonization discharge port 25 has a calorific value of about 21.0 to 23.1 MJ / kg and is a high-quality fuel that can be used for pellet burners 13, thermal power generation, etc.

[0030] In this embodiment, the conveying means 24 of the carbonization device 20 is provided with a protrusion extending in the axial direction formed in the heating chamber 22, and the heating chamber 22 is inclined toward the downstream side. With this configuration, the carbonization raw material M2 can be uniformly carbonized and the carbonization raw material M2 can be conveyed. Specifically, the heating chamber 22 inclined toward the downstream side is rotated to convey the carbonization raw material M2 to the downstream side, and the internal protrusion performs uniform carbonization of the carbonization raw material M2. Further, on the downstream side of the heating chamber 22 of the carbonization device 20, a combustible gas outlet 30 for leading out the combustible gas CG generated in the heating chamber 22 is provided.

[0031] In this embodiment, the combustible gas CG derived from the combustible gas outlet 30 is purified and recovered by the combustible gas treatment device 31. This combustible gas CG may be used as a heat source for a boiler or the like, and can also be used as fuel for the power generation unit 70 as in the second embodiment described later. In addition, the tar removed by the purification of the combustible gas treatment device 31 can also be used as a heat source for a boiler or the like.

[0032] The drying device 40 is a device that dries the water-containing raw material M1 such as sludge and livestock manure by directly contacting hot air while stirring it, and has a dryer main body 41 having a cylindrical space inside, and rotates around a rotating shaft 42 provided along the axial direction inside the dryer main body 41, and includes stirring means 43 for stirring the water-containing raw material M1 supplied therein.

[0033] In addition, the drying device 40 includes a hot air supply port 44 provided on the upstream side of the dryer main body 41 to which hot air is supplied, a drying input port 45 provided on the upstream side of the dryer main body 41 into which the water-containing raw material M1 is input, a drying discharge port 46 provided on the downstream side of the dryer main body 41, and a guide 47 for guiding the dried dried raw material M3. A cooling mechanism may be provided in the guide 47 so that the dried raw material M3 can be cooled.

[0034] In addition, the drying device 40 includes an exhaust port 48 provided on the downstream side of the dryer main body 41, a cyclone 49 connected to the exhaust port 48, and an exhaust gas treatment device 50 for treating the exhaust gas after the solid matter such as ash is separated by the cyclone 49.

[0035] The stirring means 43 has an arm 43a extending radially from the rotating shaft 42 and fins 43b provided at the tips of the arms 43a. As shown in FIG. 2, the fins 43b are attached to the arms 43a so as to be inclined with respect to the axial direction of the rotating shaft 42, and are configured to convey the water-containing raw material M1 input from the drying input port downstream while stirring it.

[0036] The dried raw material M3, which is the result of drying by the drying device 40, includes what is discharged from the drying discharge port 46 and what is separated and discharged by the cyclone 49 from the exhaust gas discharged from the exhaust port 48.

[0037] FIG. 2 is a plan view of the main part of the fuelization system 1 of the present embodiment as viewed from above. As shown in FIG. 2, in the fuelization system 1 of the present embodiment, the heat source device 10, the carbonization device 20, and the drying device 40 are provided adjacent to each other in parallel. The secondary combustion chamber 16 of the heat source device 10 and the outer chamber 21 of the carbonization device 20 are connected by a short first hot air duct 11.

[0038] Further, the second hot air duct 12 connecting the hot air outlet 29 of the carbonization device 20 and the hot air supply port 44 of the drying device 40 is provided with an adjustment damper 12a capable of adjusting the flow rate of the hot air discharged from the carbonization device 20 and flowing into the drying device 40. The hot air discharged from the carbonization device 20 is adjusted by the adjustment damper 12a for the amount flowing into the second hot air duct 12 and the amount introduced into the exhaust gas treatment device 50.

[0039] Thus, by using the adjustment damper 12a in the second hot air duct 12 connecting the carbonization device 20 and the drying device 40, the flow rate of the hot air flowing into the drying device 40 can be adjusted, so that the drying state of the drying device 40 can be adjusted. Further, with this configuration, the carbonization device 20 can be operated without operating the drying device 40. Therefore, for example, even when the drying device 40 is under maintenance, the carbonization device 20 can be operated to generate the carbide C.

[0040] Next, the operation of the fuelization system 1 of the present embodiment will be described with reference to FIGS. 1 and 2. When starting the fuelization system 1, first, fuel is supplied to the fuel supply port 14 of the pellet burner 13 of the heat source device 10 and ignited to start combustion. It is preferable to use the carbide C carbonized by the carbonization device 20 as the fuel at that time. If there is no carbide C, a fuel having the same calorific value as the carbide C may be used.

[0041] The hot air generated by the heat source device 10 is introduced into the heating passage 27 of the carbonization device 20 via the first hot air duct 11, and heating is performed in the heating chamber 22. Further, the hot air that has passed through the heating passage 27 is introduced into the interior of the dryer body 41 of the drying device 40 via the hot air outlet 29 and the second hot air duct 12, and the interior is heated. The hot air that has heated the interior of the dryer body 41 is sent from the exhaust port 48 to the exhaust gas treatment device 50 via the cyclone 49.

[0042] Thus, after the warm-up of each device is performed, the carbonization raw material M2 is introduced into the carbonization device 20, and the water-containing raw material M1 is introduced into the drying device 40.

[0043] In the carbonization device 20, the carbonization raw material M2 introduced from the carbonization inlet 23 is heated while being conveyed to the conveying means 24 inside the heating chamber 22, and carbonization treatment is performed. When the carbonization raw material M2 is heated, a part of the carbonization raw material M2 becomes the combustible gas CG, and the solid matter is carbonized to become the carbide C. The combustible gas CG is led out from the combustible gas outlet 30 and purified and recovered by the combustible gas treatment device 31.

[0044] In the drying device 40, the water-containing raw material M1 introduced from the drying inlet 45 is stirred by the stirring means 43 and conveyed downstream inside the dryer body 41 while being gradually dried by the hot air supplied from the hot air supply port 44. The dried raw material M3 generated by being dried inside the dryer body 41 is discharged to the outside from the drying discharge port 46. Further, the dried raw material M3 stirred by the stirring means 43 and floating by the hot air is discharged to the outside from the exhaust port 48, and the solid content is separated by the cyclone 49 and discharged to the outside from the cyclone 49.

[0045] According to the fuelization system 1 of the present embodiment, when the water-containing raw material M1 is sewage sludge having a water content of 70% to 80%, the water content could be reduced to 10% to 20% when it became the dried raw material M3.

[0046] Conventionally, a large amount of fossil fuels have been used when dehydrating and incinerating water-containing raw materials M1 such as sludge. However, according to the fuel conversion system 1 of the present embodiment, the water-containing raw materials M1 such as sludge to be processed are dried in the drying device 40 to obtain dried raw materials M3, which are carbonized in the carbonization device 20 to obtain carbide C, and this is used as fuel in the pellet burner 13. Therefore, the use of fossil fuels can be significantly reduced.

[0047] In addition, in the fuel conversion system 1 of the present embodiment, not only sludge and livestock manure, but also many substances such as residues related to food products (coffee grounds, agricultural product processing residues, loss products of processed foods and food raw materials), plant residues such as pruning branches and grasses, etc. can be used as raw materials for drying and carbonization treatment.

[0048] For this reason, in local governments and specific regions, substances that were conventionally considered unnecessary can be converted into fuel and used as fuel within that region. Since this fuel is derived from sludge, livestock manure, etc., it becomes a so-called biomass fuel B, which greatly contributes to the realization of carbon neutrality.

[0049] In the above embodiment, the outer chamber 21 of the carbonization device 20 is a fixed type, but it is not limited to this, and the outer chamber 21 may be rotatable. Also, the conveying means 24 of the carbonization device 20 is configured to rotate with protrusions provided in the heating chamber 22 and in an inclined state. However, as long as the carbonization raw material M2 in the heating chamber 22 can be conveyed from the upstream side to the downstream side, a configuration in which spiral fins are provided in the heating chamber 22 may be adopted.

[0050] In the above embodiment, a heat exchanger may be installed in the secondary combustion chamber 16 of the heat source device 10 to extract and utilize a heat source such as superheated steam from the secondary combustion chamber 16. According to this configuration, a wide range of utilization of the heat generated by the pellet burner 13 becomes possible.

[0051] Next, the fueling system 1A, which is the second embodiment of the present invention, will be described with reference to FIG. 3. The fueling system 1A of the second embodiment is different from the above embodiment in that it includes a power generation unit 70 connected to the combustible gas outlet 30 of the carbonization device 20. In other configurations of the fueling system 1A, detailed descriptions of the configurations common to the above embodiment will be omitted.

[0052] The power generation unit 70 includes a combustible gas inlet 71, and the combustible gas inlet 71 is connected to the combustible gas outlet 30 of the carbonization device 20 by a combustible gas duct 72. A combustible gas treatment device 31 for performing tar removal and the like in the combustible gas is provided in the combustible gas duct 72.

[0053] The power generation unit 70 mainly includes a gas engine 73 and a power generation device 74. The gas engine 73 operates using the combustible gas introduced from the combustible gas inlet 71 as fuel, rotates the power generation device 74, and generates electricity. In this embodiment, this gas engine 73 uses a general gas engine circulating in the market. Similarly, the power generation device 74 also uses a general generator circulating in the market.

[0054] The gas engine 73 is provided with exhaust heat supply means 75 for recovering the exhaust gas and the exhaust heat of the exhaust system (such as an exhaust manifold) as exhaust heat gas and supplying it to the drying device 40. This exhaust heat supply means 75 is connected to the second hot air duct 12 connecting the carbonization device 20 and the drying device 40.

[0055] Since the fueling system 1A of the second embodiment has the above configuration, the combustible gas CG generated by the carbonization process of the carbonization device 20 can be used for power generation by the power generation unit 70. In addition, the exhaust gas and the exhaust heat of the exhaust system when the gas engine 73 is driven using the combustible gas CG as fuel can be used for the drying process of the drying device 40.

[0056] Thus, according to the fuel conversion system 1A of the second embodiment, by using substances such as sludge that would otherwise be waste as raw materials, while suppressing the use of other fossil fuels as much as possible, drying treatment and carbonization treatment are performed, and power generation can be carried out using the combustible gas CG generated by the carbonization treatment.

[0057] In addition, the fuel conversion system 1A of the second embodiment is configured such that the carbonization device 20 is an indirect heating type in order to efficiently utilize the hot air generated by the heat source device 10, the water-containing raw material is stirred in the drying device 40 to directly contact the hot air, and further, the exhaust heat gas of the gas engine 73 is also used in the drying device 40.

[0058] Thus, since the fuel conversion system 1A of the second embodiment efficiently utilizes the hot air generated by the heat source device 10, it is possible to secure the amount of energy for operating the entire system with the calorific value potentially possessed by the water-containing raw material M1.

[0059] That is, once the system starts operating, the system can be continuously operated without replenishing fossil fuel from the outside. Also, since power generation is performed by the power generation device 74, the power used by the heat source device 10, the carbonization device 20, the drying device 40, and the power generation unit 70 can also be provided.

[0060] For example, when the amount of carbide C used per hour in the heat source device 10 is less than the amount of carbide C generated per unit time by the carbonization device 20 in a state where the drying device 40, the carbonization device 20, or all of the heat source device 10 is operated using the power generated by the power generation device 74, it is not necessary to supply the biomass fuel B used in the heat source device 10 from the outside.

[0061] Therefore, although a large amount of fossil fuel was conventionally required for treating sludge and the like, according to the fuel conversion system 1A of the present invention, the treatment of the water-containing raw material M1 such as sludge can be continuously performed without requiring fossil fuel or the supply of power from the outside.

[0062] In the fuel conversion system 1A of the second embodiment, although the exhaust heat supply means 75 recovers the exhaust gas and the exhaust heat of the exhaust system as exhaust heat gas, only the exhaust gas of the gas engine 73 may be used as the exhaust heat gas.

[0063] In addition, the fuel conversion systems 1 and 1A of the present embodiment are designed to be installed within a site approximately 30 m × 30 m in length and width and approximately 8 m in height, including the heat source device 10, the carbonization device 20, the drying device 40, the exhaust gas treatment device 50, the power generation unit 70, and the like. Therefore, for example, it is possible to introduce a system that can effectively utilize unused facilities such as a disused school gymnasium and generate fuel and electricity from waste such as sludge, thereby reducing the burden for local municipalities for installation.

Explanation of Reference Numerals

[0064] 1, 1A... Fuel conversion system 10... Heat source device 11... First hot air duct (hot air duct) 12... Second hot air duct (hot air duct) 20... Carbonization device 21... Outer chamber 22... Heating chamber 23... Carbonization inlet 24... Conveying means 25... Carbonization outlet 27... Heating passage 28... Hot air supply port 40... Drying device 41... Drying machine main body 42... Rotating shaft 43... Stirring means 44... Hot air supply port 45... Drying inlet 46... Drying outlet 48... Exhaust port 73... Gas engine 74... Power generation device 75... Exhaust heat supply means B... Biomass fuel CG... Combustible gas M1... Water-containing raw material M2… Raw material for carbonization M3… Dried raw material

Claims

1. A fuel conversion system that dries and carbonizes a water-containing raw material to produce fuel, comprising: a heat source device that generates hot air using biomass fuel, a drying device that dries the water-containing raw material using the hot air, and a carbonization device that carbonizes a carbonization raw material using the hot air; the drying device is a device that dries the water-containing raw material by directly contacting the hot air with the water-containing raw material; the carbonization device is an indirect heating type device that indirectly heats the carbonization raw material; the heat source device and the carbonization device, and the carbonization device and the drying device are sequentially connected by a hot air duct; the carbonization device is heated by the hot air from the heat source device, and the hot air that has heated the carbonization device is introduced into the drying device to perform a drying process; A fuel conversion system characterized in that the dried raw material dried by the drying device is introduced into the carbonization device, and the carbonization device generates carbide as fuel.

2. The fuel conversion system according to claim 1, wherein the biomass fuel is the carbide carbonized by the carbonization device.

3. The carbonization device includes an outer chamber and a heating chamber held at a distance inside the outer chamber. The heating chamber includes a carbonization inlet into which the carbonization raw material is introduced, a conveying means provided inside the heating chamber for conveying the carbonization raw material introduced into the heating chamber to the downstream side, and a carbonization discharge port provided on the downstream side of the heating chamber. The fuel conversion system according to claim 1, wherein a heating passage is formed between the outer chamber and the heating chamber, and the heating chamber is indirectly heated by supplying the hot air from the heat source device to the heating passage.

4. The drying device includes a dryer main body having a cylindrical space inside, a stirring means that rotates around a rotating shaft provided along the axial direction of the dryer main body inside the dryer main body and stirs the water-containing raw material supplied into the dryer main body, a hot air supply port provided on the upstream side of the dryer main body to which the hot air is supplied, a drying inlet provided on the upstream side of the dryer main body into which the water-containing raw material is introduced, a drying discharge port provided on the downstream side of the dryer main body, and an exhaust port provided on the downstream side of the dryer main body. The fuel conversion system according to claim 1, wherein the dried raw material dried by the drying device includes that discharged from the drying discharge port and that separated and discharged from the exhaust gas discharged from the exhaust port.

5. The hot air duct includes a first hot air duct connecting the heat source device and the carbonization device, and a second hot air duct connecting the carbonization device and the drying device. The fuelization system according to claim 1, wherein an adjustment damper for adjusting the amount of the hot air supplied from the carbonization device to the drying device is provided in the second hot air duct.

6. The fuelization system further includes a gas engine using gas as fuel, a waste heat supply means for supplying waste heat gas including exhaust gas of the gas engine to the drying device, and a power generation device driven by the gas engine. The fuelization system according to claim 1, wherein the gas engine is driven by using combustible gas generated when the carbonization raw material is heated in the carbonization device, power generation is performed by the power generation device, and the waste heat gas is supplied to the drying device by the waste heat supply means to perform a drying process by the drying device.

7. In the fuelization system according to claim 6, the drying device dries the water-containing raw material to generate the dried raw material, the carbonization device carbonizes the dried raw material to generate the carbide, the carbide is used as the biomass fuel to generate the hot air by the heat source device, with the power generated by the power generation device used to operate any one or all of the drying device, the carbonization device, or the heat source device, the fuelization system is characterized in that the amount of the carbide used per unit time in the heat source device is less than the amount of the carbide generated per unit time by the carbonization device.

Images