Method for producing carbide, apparatus for producing carbide, method for producing reformed gas, system for producing reformed gas, method for producing hydrogen, and system for producing hydrogen

Abstract

To provide a method for producing a carbide, which is excellent in a carbonization rate of organic polymer materials such as plastics, and a system for producing a carbide.SOLUTION: A method for producing a carbide comprises carbonizing a raw material comprising: an organic polymer material; and biomass. An apparatus for producing a carbide includes: a carbonization facility for carbonizing the raw material to obtain the carbide; and a raw material supply facility for supplying the raw material comprising an organic polymer material and biomass to the carbonization facility.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for producing carbide, an apparatus for producing carbide, a method for producing reformed gas, a reformed gas production system, a method for producing hydrogen, and a hydrogen production system.

Background Art

[0002] Wastes of plastic products (hereinafter also referred to as waste plastics) are discharged in large quantities as household waste and industrial waste, causing environmental problems. In particular, micro-crushed waste plastics are causing serious environmental damage to the survival of marine organisms. For this reason, the need for technologies for reducing the volume and recycling of waste plastics is increasing. So far, waste plastics have generally been used as combustion fuel or buried as waste. In recent years, technologies for thermally decomposing and gasifying waste plastics using oxygen, air, and steam at high temperatures, and technologies for producing carbide by carbonizing plastics have been developed (see Non-Patent Documents 1 to 4).

[0003] On the other hand, a direct reformed gas production method in which biomass raw materials such as grass wood, rice straw, and bagasse, and waste biomass such as construction wood, cotton, paper, and food waste are directly reacted with steam, oxygen, or air in a high temperature range to produce reformed gas, and a reformed gas production technology in which biomass is carbonized and the resulting carbide is reacted with steam to produce reformed gas have been developed (see Non-Patent Documents 5 to 8). The reformed gas produced by the gasification technology of biomass is a mixed gas containing carbon monoxide (CO), hydrogen, methane, ethylene, ethane, carbon dioxide (CO2), etc. As methods of using reformed gas, there are gas engine power generation, hydrogen production applying steam reforming reaction, etc. (see Patent Documents 1 to 3, Non-Patent Document 9).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

[0005] [Non-Patent Document 1] Narumiaki Kasaoka, Yusuke Sakata, Atsuyuki Mimura, Hideo Yado, "Manufacture of Activated Carbon from Various Plastics", Bulletin of the Chemical Society of Japan, Vol. 10 (1976), pp1631 - 1640 [Non-Patent Document 2] Takayoshi Yagasaki, Yuji Kimura, Kozo Sato, "Characterization of Carbides by Carbonization Treatment of Plastic Waste", Journal of Environmental System Measurement and Control, Vol. 5, No. 2 (2000), pp119 - 124 [Non-Patent Document 3] Tadashi Hattori, "Utilization Technology of Waste Plastics as Carbon Materials", Electric Steelmaking, Vol. 76, No. 1 (2005), P27 - 32 [Non-Patent Document 4] Kenji Kato, Makoto Nomura, Koichi Fukuda, Hiroshi Uematsu, Hirotoshi Kondo, "Technology for Chemical Raw Materialization of Waste Plastics Using Coke Ovens", Nippon Steel Technical Report, Vol. 384 (2006), pp69 - 73 [Non-Patent Document 5] Supervised by Masaru Ichikawa, "New Developments in Biomass Refinery Catalyst Technology", CM&C Publishing (2011), pp70 - 77, pp99 - 106 [Non-Patent Document 6] D. Xianwen et al., Energy Fuels 14, 2000, 552 [Non-Patent Document 7] I. D. Barn et al., Energy Fuels 14, 2000, 889 [Non-Patent Document 8] Kenichi Sasaki, "Power Generation Utilization by Thermal Decomposition Gasification of Biomass", Journal of the Combustion Institute of Japan, Vol. 47, No. 139 (2005), pp31 - 39 [Non-Patent Document 9] Masaru Ichikawa, "New Developments in Hydrogen Energy Technology Utilizing Biomass Resources", Life and Environment, Vol. 61, No. 1 (2016) [Summary of the Invention] [Problems to be Solved by the Invention]

[0006] In the conventional plastic carbonization technology, the weight carbonization rate of plastic (carbide / plastic × 100) is at most 5 - 20%, and improvement of the carbonization rate of plastic and increase in carbide yield are required. In addition, in the conventional technology, in the carbonization process, in addition to gases that can be used as fuels such as hydrogen and low-molecular-weight hydrocarbons (methane, ethane, propane, etc.), by-products such as oily components and tar are generated. For this reason, reduction of the treatment cost of by-products and the burden on the regional environment is required. Also, improvement of the reformed gas and hydrogen production efficiency in the steam reforming gasification of the carbide and the hydrogen production process, energy saving of the reformed gas production and hydrogen production operations, reduction of hydrogen production cost, and reduction of the emission amount of greenhouse gas substances such as CO2 are required.

[0007] Therefore, an object of the present invention is to provide a method for producing a carbide having an excellent carbonization rate of an organic polymer material such as plastic and a carbide production apparatus, and a method for producing a reformed gas, a reformed gas production system, a method for producing hydrogen, and a hydrogen production system using the same. [Means for Solving the Problems]

[0008] The present invention has the following aspects. [1] A method for producing a carbide by carbonizing a raw material containing an organic polymer material and biomass. [2] The production method according to [1], wherein the mass ratio of the organic polymer material to the biomass is 0.01 - 99. [3] The production method according to [1] or [2], wherein the carbide is for producing a reformed gas containing hydrogen and carbon monoxide. [4] The production method according to [3], wherein the biomass contains at least one metal element selected from the group consisting of sodium, potassium, lithium, cesium, calcium, magnesium, strontium, barium, boron, aluminum, iron, titanium, molybdenum, and tungsten. [5] The production method according to [4], wherein the content of the metal element is 0.01 to 100 g per 1 kg of the biomass. [6] A carbonization facility for carbonizing a raw material to obtain a carbide, A raw material supply facility for supplying a raw material containing an organic polymer material and biomass to the carbonization facility, A carbide production apparatus comprising: [7] The carbide production apparatus according to [6], wherein the mass ratio of the organic polymer material to the biomass is 0.01 to 99. [8] The carbide production apparatus according to [6] or [7], wherein the carbide is for producing a reformed gas containing hydrogen and carbon monoxide. [9] The carbide production apparatus according to [8], wherein the biomass contains at least one metal element selected from the group consisting of sodium, potassium, lithium, cesium, calcium, magnesium, strontium, barium, boron, aluminum, iron, titanium, molybdenum, and tungsten.

[10] The carbide production apparatus according to [9], wherein the content of the metal element is 0.01 to 100 g per 1 kg of the biomass.

[11] Producing a carbide by any of the production methods according to [1] to [5], Performing reforming gasification including at least a reaction between the carbide and steam to obtain a reformed gas containing hydrogen and carbon monoxide, a method for producing a reformed gas.

[12] The production method according to

[11] , wherein the reforming gasification includes a reaction between the carbide and carbon dioxide.

[13] Air-combusting pyrolysis products other than the carbide generated when carbonizing the raw material, Using the exhaust heat of the combustion gas generated by the air combustion of the pyrolysis products as a heat source in the reforming gasification, the production method according to

[11] or

[12] .

[14] Any of the carbide production apparatuses according to [6] to

[10] , Reforming gasification equipment for performing reforming gasification including at least a reaction between the carbide and steam to obtain a reformed gas containing hydrogen and carbon monoxide, A reformed gas production system comprising:

[15] The reforming gasification reforming gas production system of

[14] above, which includes the reaction of the carbide with carbon dioxide.

[16] Air combustion equipment for air combustion of pyrolysis products other than the carbide generated by the carbide production device, Waste heat utilization equipment for using the waste heat of the combustion gas generated by the air combustion of the pyrolysis products as a heat source in the reforming gasification equipment, The reforming gas production system of

[14] or

[15] above, which is equipped with the above.

[17] Produce reforming gas by any of the production methods of

[11] to

[13] above, Obtain a mixed gas containing hydrogen and carbon dioxide at a higher concentration than the reforming gas by the shift reaction of carbon monoxide and steam in the reforming gas, A hydrogen production method for performing hydrogen purification treatment on the mixed gas.

[18] Air-combust the pyrolysis products other than the carbide generated when carbonizing the raw material, The production method of

[17] above, which uses the waste heat of the combustion gas generated by the air combustion of the pyrolysis products as a heat source in the reforming gasification and the shift reaction.

[19] The production method of

[17] or

[18] above, in which the shift reaction is carried out in the presence of a hydrogenation catalyst.

[20] The production method of

[19] above, in which the hydrogenation catalyst includes at least one element selected from iron, ruthenium, nickel, copper, zinc, chromium, cobalt, molybdenum, zirconia, titanium, cerium, lanthanum, and neodymium, and a porous oxide carrier.

[21] The production method of any of

[17] to

[20] above, in which the hydrogen purification treatment includes gas separation treatment by either one or both of a pressure swing adsorption type gas separation device and a gas separation membrane type gas separation device.

[22] The production method of

[21] above, which recovers the carbon dioxide separated by the gas separation treatment and uses the recovered carbon dioxide for the reforming gasification.

[23] Any of the reforming gas production systems of

[14] to

[16] above, and A mixed gasification facility comprising a shift reactor, which obtains a mixed gas containing hydrogen and carbon dioxide at a higher concentration than the reformed gas through a shift reaction between carbon monoxide and steam in the reformed gas, a hydrogen purification facility that performs hydrogen purification treatment on the mixed gas, and a hydrogen production system comprising the same.

[24] An air combustion facility that air-combusts pyrolysis products other than the carbide produced in the carbonization facility of the carbide production apparatus, and an exhaust heat utilization facility that uses the exhaust heat of the combustion gas generated by the air combustion of the pyrolysis products as a heat source in the reformed gasification facility and the mixed gasification facility. The hydrogen production system according to

[23] , comprising the same.

[25] The hydrogen production system according to

[23] or

[24] , wherein the shift reactor contains a hydrogenation catalyst.

[26] The hydrogen production system according to

[25] , wherein the hydrogenation catalyst contains at least one element selected from iron, ruthenium, nickel, copper, zinc, chromium, cobalt, molybdenum, zirconia, titanium, cerium, lanthanum, and neodymium, and a porous oxide carrier.

[27] The hydrogen production system according to any one of

[23] to

[26] , wherein the hydrogen purification facility includes one or both of a pressure swing adsorption type gas separation device and a gas separation membrane type gas separation device.

[28] The hydrogen production system according to

[27] , wherein the reformed gasification facility includes means for recovering carbon dioxide separated by the gas separation device and supplying it to the reformed gasification facility. [Advantages of the Invention]

[0009] According to the present invention, it is possible to provide a method for producing a carbide excellent in the carbonization rate of an organic polymer material such as plastic, a carbide production apparatus, a method for producing a reformed gas using the same, a reformed gas production system, a method for producing hydrogen, and a hydrogen production system. [Brief Description of the Drawings]

[0010]

Figure 1

Figure 2

Embodiments for Carrying Out the Invention

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Hereinafter, "Pressure Swing Adsorption" will also be referred to as PSA. "~" indicating a numerical range means that the numerical values described before and after it are included as the lower limit value and the upper limit value.

[0012] <Hydrogen Production System> FIG. 1 is a schematic diagram of a hydrogen production system 100 according to an embodiment of the present invention. The hydrogen production system 100 includes a raw material supply facility 10, a carbonization facility 20, a reforming gasification facility 30, a mixed gasification facility 40, a hydrogen purification facility 50, an air combustion facility 60, and a waste heat utilization facility 70. The raw material supply facility 10, the carbonization facility 20, and the air combustion facility 60 constitute a carbide production apparatus in the present embodiment. The raw material supply facility 10, the carbonization facility 20, the reforming gasification facility 30, the air combustion facility 60, and the waste heat utilization facility 70 constitute a reforming gas production system in the present embodiment.

[0013] The raw material supply facility 10 includes a biomass receiver 11 for storing biomass B, a rotary kiln dryer 12 for drying the biomass B supplied from the biomass receiver 11, an organic polymer material storage silo 13 for storing the organic polymer material P, a raw material receiver 14, and a conveyor feeder 15. The raw material receiver 14 stores the biomass B dried by the rotary kiln dryer 12 and the organic polymer material P supplied from the organic polymer material storage silo 13. The conveyor feeder 15 supplies the biomass B and the organic polymer material P in the raw material receiver 14 to the carbonization facility 20.

[0014] Examples of the biomass B include forest logging materials such as cedar, pine, and bamboo, agricultural products and by-products such as rice straw and sugarcane, construction waste, industrial waste such as cotton and fiber products, and crushed materials obtained by crushing these biomasses (hereinafter also referred to as biomass chips). As the biomass B, biomass chips are preferred. The size of the biomass chips is, for example, 5 to 100 mm. The biomass B may be used alone or in combination of two or more.

[0015] Biomass generally contains at least one metal element selected from the group consisting of sodium, potassium, lithium, cesium, calcium, magnesium, strontium, barium, boron, aluminum, iron, titanium, molybdenum, and tungsten. However, a biomass having the metal element further supported thereon may also be used as the biomass B. Hereinafter, the biomass before the metal element is supported is also referred to as the biomass main body. Examples of the method for supporting the metal element on the biomass main body include a method of immersing the biomass main body in a solution in which a component containing the metal element is dissolved in a solvent such as water, alcohol, ether, or hydrocarbon, and a method of spraying the solution onto the biomass main body.

[0016] The content of the metal element in the biomass B is preferably 0.01 to 100 g, more preferably 0.1 to 50 g, and even more preferably 0.5 to 25 g per 1 kg of the biomass B. If the content of the metal element is within the above range, the carbonization rate of the organic polymer material tends to be more excellent. The content of the metal element is measured by ion chromatography, ICP emission spectrometry, and X-ray fluorescence spectrometry. The content of the metal element in the biomass main body varies depending on the type of the biomass main body, but is about 0.1 to 2 g per 1 kg of the biomass main body.

[0017] The organic polymer material P includes organic polymers such as plastics and elastomers. Examples of organic polymers include polyolefins such as polyethylene (PE) and polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), polyvinyl chloride (PCV), polyacrylonitrile (PAN), acrylonitrile-butadiene-styrene resin (ABS), acrylonitrile-styrene resin (AS), phenolic resin, vinyl acetate resin, epoxy resin, polycarbonate, polyimide resin, melanin resin, polyurethane, rubber, etc. The organic polymer material P may contain additives and may also contain a liquid medium (such as an organic solvent or water). The organic polymer material P may be a molded article, a paint, an adhesive, a composite thereof, a crushed product of a molded article or a composite, etc. Examples of the molded article include containers such as bottles, fibers, films, and tires. Examples of the composite include a coated article obtained by coating a molded article with a paint, and a laminate obtained by laminating a plurality of molded articles via an adhesive. The size of the crushed product is preferably 0.1 to 10 cm, more preferably 1 to 5 cm, for example. The organic polymer material P may be used alone or in combination of two or more.

[0018] The carbonization facility 20 includes a carbonization furnace 21 and a carbide receiver 22. A conveyor feeder 15 is connected to the middle part of the carbonization furnace 21. The raw materials (biomass B and organic polymer material P) in the raw material receiver 14 are transferred by the conveyor feeder 15 and fed into the carbonization furnace 21. The supply of the raw materials to the carbonization furnace 21 may be continuous or intermittent.

[0019] The carbonization furnace 21 carbonizes the raw materials. In this embodiment, since the raw materials include biomass B and organic polymer material P, the carbonization furnace 21 co-carbonizes biomass B and organic polymer material P. In the carbonization of the raw materials, the raw materials are heated and pyrolyzed in a low oxygen state or an oxygen-free state. When the raw materials are pyrolyzed, carbide C1 is generated. Also, pyrolysis products C2 other than carbide such as decomposition gas and tar are generated. The carbide receiver 22 is disposed below the carbonization furnace 21. The carbide C1 generated in the carbonization furnace 21 is discharged from the bottom of the carbonization furnace 21 and stored in the carbide receiver 22.

[0020] The reforming gasification facility 30 includes a carbide feeder 31, a reforming gasification furnace 32, a steam supply passage 33, a carbon dioxide supply passage 34, and a reformed gas passage 35. The carbide feeder 31 supplies the carbide C1 in the carbide receiver 22 to the reforming gasification furnace 32. One end of the carbide feeder 31 is connected to the carbide receiver 22, and the other end is connected to the upper part or the middle part of the reforming gasification furnace 32. The steam supply passage 33 supplies steam to the reforming gasification furnace 32. One end of the steam supply passage 33 is connected to the lower part of the reforming gasification furnace 32, and the other end is connected to the supply source of the raw water W. A flow controller may be installed in the steam supply passage. The carbon dioxide supply passage 34 supplies carbon dioxide to the reforming gasification furnace 32. A flow controller may be installed in the carbon dioxide supply passage 23. The supply of carbon dioxide to the reforming gasification furnace 32 may be continuous or intermittent.

[0021] The reforming gasification furnace 32 performs reforming gasification of the carbide C1. The reforming gasification includes the reaction of carbide C1 and steam (C + H2O → H2 + CO). Also included are the methanation reaction (C + 2H2 → CH4), the shift reaction (CO + H2O → CO2 + H2), the reaction of carbide C1 and carbon dioxide (C + CO2 → 2CO), etc. The reformed gas generated by reforming gasification contains hydrogen (H2), carbon monoxide (CO), methane (CH4), and carbon dioxide (CO2).

[0022] In the present embodiment, the reforming gasification furnace 32 includes an inner cylinder part 32a and an outer cylinder part 32b surrounding the inner cylinder part 32a. The carbide C1 is accommodated in the inner cylinder part 32a. By supplying heating gas to the gap between the inner cylinder part 32a and the outer cylinder part 32b, the inner cylinder part 32a is heated, and reforming gasification proceeds due to the heat.

[0023] The reformed gas flow path 35 leads out the reformed gas from the reforming gasifier 32. One end of the reformed gas flow path 35 is connected to the top of the reforming gasifier 32. The other end of the reformed gas flow path 35 is connected to the shift reactor 41 of the mixed gasification facility 40. In the present embodiment, the reformed gas flow path 35 also serves as a means for supplying the reformed gas to the shift reactor 41. A flow rate controller may be installed in the reformed gas flow path 35.

[0024] A reformed gas purification section 36 is provided in the middle of the reformed gas flow path 35. In the present embodiment, the reformed gas purification section 36 is equipped with a dust collector. Residual carbide and ash (hereinafter also referred to as solid content S) are discharged from the top of the reforming gasifier 32 together with the reformed gas. The dust collector separates the reformed gas and the solid content S and discharges the separated solid content S. Since the ash contains the metal element, the discharged solid content S may be recovered and used to carry the metal element on the biomass body. Examples of the dust collector include a cyclone and a bag filter, and they may be used in combination. The reformed gas purification section 36 may be equipped with a desulfurization device, a dechlorination device, etc.

[0025] The mixed gasification facility 40 includes a shift reactor 41, a heat exchanger 42 for reformed gas, a steam supply path 43, a mixed gas flow path 44, and a mixed gas holder 45.

[0026] The shift reactor 41 performs a shift reaction (CO + H2O → CO2 + H2) between carbon monoxide and steam in the reformed gas. Thereby, a mixed gas containing hydrogen and carbon dioxide at a higher concentration than the reformed gas is obtained. The shift reactor 41 preferably contains a hydrogenation catalyst. By performing the shift reaction in the presence of the hydrogenation catalyst, mixed gasification can be carried out in a relatively low temperature range of 350 to 600 °C. Thereby, the consumption of external fuels (such as heavy oil and electricity) can be reduced, and the production cost of hydrogen and the CO2 emission amount can be reduced. Examples of the hydrogenation catalyst include those containing at least one element selected from iron, ruthenium, nickel, copper, zinc, chromium, cobalt, molybdenum, zirconia, titanium, cerium, lanthanum, and neodymium, and a porous oxide carrier.

[0027] The reformed gas heat exchanger 42 is connected to the reformed gas flow path 35 and the steam supply path 43 on the downstream side of the reformed gas purification unit 36. The steam supply path 43 supplies steam to the shift reactor 41. One end of the steam supply path 43 is connected to the shift reactor 41, and the other end is connected to the steam supply path 33. A flow controller may be installed in the steam supply path 43. In the mixed gasification facility 40, the raw water W supplied through the steam supply path 33 and the steam supply path 44 is heated by the heat of the reformed gas in the reformed gas heat exchanger 42 so that it can be supplied to the shift reactor 41 as steam.

[0028] The mixed gas flow path 44 leads out the mixed gas from the shift reactor 41. One end of the mixed gas flow path 44 is connected to the shift reactor 41. The other end of the mixed gas flow path 44 is connected to the gas separation device 51 of the hydrogen purification facility 50. In this embodiment, the mixed gas flow path 44 also serves as a means for supplying the mixed gas to the hydrogen purification facility 50. A mixed gas holder 45 for storing the mixed gas is provided in the middle of the mixed gas flow path 44.

[0029] The hydrogen purification facility 50 performs hydrogen purification treatment of the mixed gas. By the hydrogen purification treatment, high-purity hydrogen (for example, with a purity of 99.8% or more) can be obtained. In this embodiment, the hydrogen purification facility 50 includes a gas separation device 51. The gas separation device 51 separates the gases constituting the mixed gas. Examples of the gas separation device 51 include a PSA type gas separation device and a gas separation membrane type gas separation device. Either one of these gas separation devices may be used alone, or both may be used. A hydrogen holder 52 is connected to the gas separation device 51. The hydrogen holder 52 stores hydrogen separated from the mixed gas by the gas separation device 51. Further, a carbon dioxide supply line 34 is connected to the gas separation device 51. In the present embodiment, the carbon dioxide supply line 34 constitutes means for recovering carbon dioxide separated by the gas separation device 51 and supplying it to the reforming gasification facility 30. Carbon dioxide separated from the mixed gas by the gas separation device 51 can be supplied to the reforming gasification furnace 32 via the carbon dioxide supply line 34 and used for reforming gasification.

[0030] The air combustion facility 60 includes an air blower 61. The air blower 61 is connected to the upper part of the carbonization furnace 21. By supplying air to the upper part of the carbonization furnace 21 by the air blower 61, the pyrolysis product C2 can be burned in air.

[0031] The waste heat utilization facility 70 includes a first combustion gas flow path 71, a second combustion gas flow path 72, a heat exchanger 73 for steam, a heat exchanger 74 for air, an air supply path 75, an exhaust gas discharge path 76, and an exhaust gas outlet tower 77. One end of the first combustion gas flow path 71 is connected to the top of the carbonization furnace 21, and the other end is connected to the upper part of the reforming gasification furnace 32. One end of the second combustion gas flow path 72 is connected to the lower part of the reforming gasification furnace 32, and the other end is connected to the rotary kiln dryer 12. The heat exchanger 73 for steam is connected to the second combustion gas flow path 72 and the steam supply line 33. The heat exchanger 74 for air is connected to the second combustion gas flow path 72 and the air supply path 75 on the downstream side of the heat exchanger 73 for steam. One end of the exhaust gas discharge path 76 is connected to the rotary kiln dryer 12, and the other end is connected to the exhaust gas outlet tower 77.

[0032] In the waste heat utilization facility 70, the combustion gas generated by the air combustion of the pyrolysis product C2 is supplied between the inner cylinder part 32a and the outer cylinder part 32b of the upper part of the reforming gasification furnace 32 and discharged from the lower part. At this time, the inner cylinder part 32a is heated by the waste heat of the combustion gas and used for reforming gasification. In the steam heat exchanger 73, the exhaust heat of the combustion gas discharged from the reforming gasifier 32 is used to heat the feed water W passing through the steam supply passage 33. The heated feed water W is supplied to the reforming gasifier 32 as steam and used for reforming gasification. In the air heat exchanger 74, the exhaust heat of the combustion gas, a part of which has been used for exhaust heat in the steam heat exchanger 73, is used to heat the air passing through the air supply passage 75. The heated air is used to dry the biomass in the rotary kiln dryer 12, and then passes through the exhaust gas discharge passage 76 and is discharged from the exhaust gas outlet tower 77. The combustion gas after the exhaust heat is used in the air heat exchanger 74 is released into the atmosphere from the gas tower outlet.

[0033] <Hydrogen production method> Next, an example of a hydrogen production method using the hydrogen production system 100 will be described. FIG. 2 is a process flow diagram of the hydrogen production method of the present embodiment.

[0034] (Production of carbide) First, the biomass B is received by the biomass receiver 11 of the raw material supply facility 10, dried by a rotary kiln dryer 12 in a predetermined amount, supplied to the raw material receiver 14, and supplied into the carbonization furnace 21 of the carbonization facility 20 by a kiln type conveyor feeder 15. Separately, the organic polymer material P is received by the organic polymer material storage silo 13, supplied to the raw material receiver 14 in a predetermined amount, and supplied into the carbonization furnace 21 of the carbonization facility 20 by a kiln type conveyor feeder 15. At this time, the organic polymer material P and the biomass B may be individually supplied into the carbonization furnace 21, or may be mixed in the raw material receiver 14 in advance and supplied into the carbonization furnace 21. Next, the inside of the carbonization furnace 21 is heated to 350 to 600 ° C to co-carbonize the organic polymer material P and the biomass B. Thereby, the carbide C1 is obtained. At this time, the organic polymer material P and the biomass B may be stirred and mixed by a turntable or a screen method. The pressure inside the carbonization furnace 21 is, for example, normal pressure. The carbide C1 generated in the carbonization furnace 21 is taken out from the bottom of the carbonization furnace 21, subjected to a crushing process as necessary, and then stored in the carbide receiver 22.

[0035] In the production of carbide, the supply amount of the raw material containing the organic polymer material P and the biomass B to the carbonization furnace 21 is preferably 10 to 10000 kg / h, and more preferably 100 to 5000 kg / h. The mass ratio of the organic polymer material P to the biomass B (organic polymer material P / biomass B) is preferably 0.01 to 99, more preferably 0.05 to 50, and even more preferably 0.1 to 10. If the mass ratio of the organic polymer material P / biomass B is within the above range, the carbonization rate of the raw material will be further increased. By increasing the carbonization rate, the production amount of carbide, the production amount of reformed gas, and the production amount of hydrogen will also increase.

[0036] (Production of reformed gas) Next, a predetermined amount of carbide C1 is supplied from the carbide receiver 22 into the reforming gasifier 32 by the carbide feeder 31. Separately, air is blown into the upper part of the carbonization furnace 21 by the air blower 61 to air-combust the pyrolysis products C2 such as the decomposition gas and tar generated in the carbonization furnace 21. The temperature of the generated combustion gas is, for example, 1000 to 1200 °C. The generated combustion gas sequentially passes through the reforming gasifier 32, the heat exchanger 73 for steam, and the heat exchanger 74 for air. At this time, the heat of the combustion gas is used for heating the reforming gasifier 32, the feed water W passing through the steam supply line 33, and the air passing through the air supply line 75, respectively.

[0037] During reforming gasification, the reforming gasifier 32 is heated to, for example, 800 to 900 °C. The feed water passing through the steam supply line 33 is heated to steam at, for example, 350 to 800 °C and supplied to the reforming gasifier 32. The air passing through the air supply line 75 is heated to, for example, 250 to 350 °C and supplied to the rotary kiln dryer 12. By using the heat of the combustion gas for these heating processes, reforming gasification and biomass drying can be carried out with a smaller consumption amount than before, even without heating by external fuels (such as heavy oil and electricity) or when using the combustion gas generated by air-combusting external fuels in combination.

[0038] During the reforming gasification, it is preferable to supply carbon dioxide from the carbon dioxide supply line 34 to the reforming gasification furnace 32. By supplying carbon dioxide, the amount of reforming gas produced can be improved, for example, 1.2 to 2.5 times compared to the case where carbon dioxide is not supplied with only steam supply.

[0039] In the reforming gasification furnace 32, reactions such as the reaction of carbide C1 with steam (C + H2O → H2 + CO), methanation reaction (C + 2H2 → CH4), shift reaction (CO + H2O → CO2 + H2), and reaction of carbide C1 with carbon dioxide (C + CO2 → 2CO) proceed continuously, and reforming gas is generated. The reforming gas generated in the reforming gasification furnace 32 is introduced from the top of the reforming gasification furnace 32 into the reforming gas flow path 35, and reforming gas purification treatment such as removal of solid content S is performed in the reforming gas purification unit 36. As the reforming gas purification treatment, desulfurization treatment, dechlorination treatment, etc. may be performed.

[0040] The supply amount of carbide C1 to the reforming gasification furnace 32 is preferably 10 to 10000 kg / h, and more preferably 50 to 5000 kg / h. The supply amount of steam per 1 kg / h of the supply amount of carbide C1 to the reforming gasification furnace 32 is preferably 0.5 to 10 kg / h, and more preferably 2 to 5 kg / h. When supplying carbon dioxide to the reforming gasification furnace 32, the supply amount of carbon dioxide per 1 kg / h of the supply amount of carbide C1 to the reforming gasification furnace 32 is 0.5 to 20 Nm 3 / h is preferable, and 2 to 10 Nm 3 / h is more preferable. When supplying carbon dioxide to the reforming gasification furnace 32, the ratio of the supply amount of carbon dioxide to the total supply amount of steam and carbon dioxide is preferably 1 to 85% by volume, and more preferably 10 to 60% by volume. The pressure inside the reforming gasification furnace 32 is, for example, 0.1 to 0.5 MPa.

[0041] The reforming gas contains hydrogen (H2) and carbon monoxide (CO), and typically contains hydrogen (H2), carbon monoxide (CO), methane (CH4), and carbon dioxide (CO2). The hydrogen content in the reformed gas is, for example, 25 to 75% by volume, and more preferably 35 to 65% by volume. The carbon monoxide content in the reformed gas is, for example, 20 to 60% by volume, and more preferably 25 to 50% by volume. The total content of hydrogen and carbon monoxide in the reformed gas is, for example, 60 to 100% by volume, and more preferably 70 to 90% by volume. The methane content in the reformed gas is, for example, 0.1 to 10% by volume, and more preferably 0.5 to 5% by volume. The carbon dioxide content in the reformed gas is, for example, 1 to 25% by volume, and more preferably 10 to 20% by volume. The content (% by volume) of each component is the value at 25 °C (room temperature) and 1 atm.

[0042] (Production of Hydrogen) Next, the reformed gas that has undergone the reformed gas purification process is supplied to the shift reactor 41 via the reformed gas flow path 35. Separately, the raw water W passing through the steam supply path 43 is heated by the heat of the reformed gas in the reformed gas heat exchanger 42 in the middle of the reformed gas flow path 35, and supplied to the shift reactor 41 as steam at, for example, 350 °C. In this embodiment, since the waste heat of the combustion gas is used for heating the reforming furnace 32 and the steam supplied to the reforming furnace 32, it can be said that the heating by the reformed gas also utilizes the waste heat of the combustion gas.

[0043] In the shift reactor 41, carbon monoxide in the reformed gas and steam are subjected to a shift reaction (CO + H2O → CO2 + H2). As a result, a mixed gas containing hydrogen and carbon dioxide at a higher concentration than the reformed gas is generated. The temperature inside the shift reactor 41 is preferably 250 to 600 °C, and more preferably 350 to 450 °C. The pressure inside the shift reactor 41 is preferably 2 to 15 atm, and more preferably 5 to 10 atm. The gas hourly space velocity (GHSV) of the reformed gas with respect to the hydrogenation catalyst is 100 - 5000 h -1 is preferable, and 500 - 3000 h -1 is more preferable.

[0044] The mixed gas generated in the shift reactor 41 is stored in the mixed gas holder 45 as necessary, and then supplied to the gas separation device 51 for gas separation processing. By performing the gas separation processing, hydrogen with a purity of 99.8% or more can be produced. The produced hydrogen is stored in the hydrogen holder 52. The carbon dioxide separated by the gas separation processing is recovered and supplied to the reforming gasification furnace 32 for use in reforming gasification (CO2 recycling).

[0045] <Operational effects> In this embodiment, since the organic polymer material and the biomass are co-carbonized, the carbonization rate is improved compared to the case where the organic polymer material and the biomass are carbonized alone. For example, conventionally, the carbonization rate of plastics is at most 5 - 25%, but in this embodiment, by co-carbonizing with biomass, the carbonization rate can be increased to 30 - 85%. Among organic polymers, organic polymers that do not contain functional groups such as chlorine atoms, nitrogen atoms, and oxygen atoms (such as PE, PP, PS, etc.) tend to be less likely to carbonize compared to organic polymers that contain functional groups (such as PET, PVC, PAN, etc.). However, in this embodiment, even for organic polymers that do not contain functional groups, by co-carbonizing with biomass, the carbonization rate can be increased to a sufficiently high value (for example, 30 - 65%). By improving the carbonization rate, the production amount of carbide, and thus the production amount of reforming gas and hydrogen, is improved. Also, the range of raw materials can be expanded compared to the prior art, and inexpensive organic polymer raw materials can be used. Therefore, the production cost of hydrogen can be reduced. The reason for the improvement in the carbonization rate is considered to be that the softened organic polymer material enters the pores of the porous biomass and the effect of the metal elements contained in the biomass promotes carbonization.

[0046] In addition, in the present embodiment, the pyrolysis products C2 other than the carbide C1 generated in the carbonization furnace 21 are burned with air, and the exhaust heat is used as a heat source in the reforming gasification and the mixed gasification. Therefore, the consumption of external fuels (such as heavy oil and electricity) can be reduced, and the production cost of hydrogen can be further reduced, which is excellent in terms of the environment and economy.

[0047] In addition, in the present embodiment, the carbon dioxide separated by the gas separation device 51 is recovered, and the recovered carbon dioxide is supplied to the reforming gasification furnace 32 and used for reforming gasification. According to the study by the present inventor, by supplying carbon dioxide to the reforming gasification furnace 32, the production amount of the reforming gas is improved by 1.2 to 2.5 times compared with the case where carbon dioxide is not supplied. Therefore, the production amount of hydrogen is improved, and the production cost of hydrogen can be further reduced.

[0048] As described above, the present invention has been described by showing the embodiments, but the present invention is not limited to the above embodiments, and can be freely changed within the scope of the present invention.

Example

[0049] Examples of the present invention are shown below. The following examples are merely illustrative of the invention, and the content of the present invention is not limited by the following examples.

[0050] [Example 1, Comparative Example 1, Comparative Example 2] A test for producing hydrogen was carried out using a hydrogen production system having the configuration shown in FIG. 1. In this test, either one or both of an organic polymer material and biomass were supplied to the carbonization furnace (both the organic polymer material and biomass in Example 1, only the organic polymer material in Comparative Example 1, and only biomass in Comparative Example 2). Carbonization in the carbonization furnace, reforming gasification in the reforming gasification furnace, mixed gasification in the shift reactor, and gas separation in the gas separation device were performed to produce hydrogen with a purity of 99.8%. A PSA type gas separation device was used as the gas separation device. The carbon dioxide separated by the gas separation device was supplied to the reforming gasification furnace. In the carbonization furnace, the pyrolysis products were burned with air, and the exhaust heat was used for reforming gasification and mixed gasification. As the organic polymer material, crushed chips of plastic [PP+PET] consisting of 50% by mass of a polypropylene container and 50% by mass of a PET bottle were charged at 30 kg per hour. As the biomass, construction waste chips (metal content per 1 kg: K 1.5 g, Ca 0.5 g, Fe 0.12 g, Mg 0.05 g) were charged at 10 kg per hour. Carbonization was carried out under the condition of a temperature of 250 to 450 °C. Reforming gasification was carried out under the conditions of steam / carbide (mass ratio) = 1.5, CO2 / carbide (molar ratio) = 0.5, and a temperature of 860 °C. Mixed gasification was carried out under the conditions of a temperature of 350 °C and a pressure of 0.1 MPa. The composition of the reformed gas components and the concentrations of CO, hydrogen, CO2, CH4, and other hydrocarbons in the outlet gas of the shift reactor were measured using a micro gas chromatograph filled with Gaskuropack and molecular sieve 13X and a Shimadzu FID gas chromatograph. The flow rate of the exhaust gas was measured using a wet gas flow meter.

[0051] The amount of carbide produced, the carbonization rate, the amount of reformed gas produced, the composition of the reformed gas components, and the amount of hydrogen produced are shown in Table 1. From these results, it was shown that by co-carbonizing plastic [PP+PET] and construction waste, the carbonization rate, the reformed gas production efficiency, and the hydrogen production efficiency were significantly improved compared to the case of carbonizing each alone.

[0052]

Table 1

[0053] [Example 2, Comparative Example 3, Comparative Example 4] As the organic polymer material, crushed chips of plastic [PS+PCV] consisting of 40% by mass of a polystyrene container and 60% by mass of a polyvinyl chloride container were charged at 20 kg per hour. As the biomass, except that cedar chips (metal content per 1 kg: K 1.0 g, Mg 0.05 g, Ba 0.02 g, Mo 0.05 g) were charged at 5 kg per hour, the same operations as in Example 1, Comparative Example 1, and Comparative Example 2 were performed.

[0054] The carbide production amount, carbonization rate, reformed gas production amount, reformed gas component composition, and hydrogen production amount are shown in Table 2. From these results, it was shown that co-carbonizing plastic [PS+PCV] and cedar chips significantly improved the carbonization rate, reformed gas production efficiency, and hydrogen production efficiency compared to carbonizing each alone.

[0055]

Table 2

[0056] [Example 3, Comparative Example 5, Comparative Example 6] As the organic polymer material, crushed chips of plastic [PE+acrylic+PCV] consisting of 25% by mass of a polyethylene container, 35% of an acrylic resin container, and 50% by mass of a polyvinyl chloride container were charged at 20 kg per hour. As the biomass, except that sugarcane bagasse chips (metal content per 1 kg: K 0.85 g, Al 0.05 g, Ca 0.2 g, Cs 0.05 g) were charged at 10 kg per hour, the same operations as in Example 1, Comparative Example 1, and Comparative Example 2 were performed.

[0057] The carbide production amount, carbonization rate, reformed gas production amount, reformed gas component composition, and hydrogen production amount are shown in Table 3. From these results, it was shown that by co-carbonizing plastic [PE + acrylic + PCV] and sugarcane bagasse chips, the carbonization rate, reformed gas production efficiency, and hydrogen production efficiency were significantly improved compared to the case of carbonizing each alone.

[0058]

Table 3

[0059] [Example 4, Comparative Example 7, Comparative Example 8] As the organic polymer material, crushed chips of plastic [PE + PP + PET + PCV] composed of 15% by mass of polyethylene containers, 25% by mass of polypropylene containers, 25% of PET containers, and 35% by mass of polyvinyl chloride containers were charged at 45 kg per hour, and as the biomass, except that cotton cloth compressed pellets (metal content per kg: K 0.50 g, Na 0.25 g, Li 0.05 g, Fe 0.05 g, Mo 0.02 g) were charged at 10 kg per hour, the same operations as in Example 1, Comparative Example 1, and Comparative Example 2 were performed respectively.

[0060] The amount of carbide produced, the carbonization rate, the amount of reformed gas produced, the reformed gas component composition, and the amount of hydrogen produced are shown in Table 4. From these results, it was shown that by co-carbonizing plastic [PE + PP + PET + PCV] and cotton cloth compressed pellets, the carbonization rate, reformed gas production efficiency, and hydrogen production efficiency were significantly improved compared to the case of carbonizing each alone.

[0061]

Table 4

Industrial Applicability

[0062] In the present invention, by co-carbonizing an organic polymer material and biomass, the carbonization rate can be improved. Therefore, the production efficiency of reformed gas from the carbide and the production efficiency of hydrogen from the reformed gas can be improved. In addition, it is possible to expand the raw material range for hydrogen production. Therefore, the production cost and environmental load of hydrogen can be reduced.

Explanation of Reference Numerals

[0063] 10 Raw material supply facility 11 Biomass receiver 12 Rotary kiln dryer 13 Organic polymer material storage silo 14 Raw material receiver 15 Conveyor feeder 15 20 Carbonization facility 21 Carbonization furnace 22 Carbide receiver 30 Reformed gasification facility 31 Carbide feeder 32 Reformed gasification furnace 33 Steam supply line 34 Carbon dioxide supply line 35 Reformed gas flow path 36 Reformed gas purification section 40 Mixed gasification facility 41 Shift reactor 42 Heat exchanger for reformed gas 43 Steam supply line 44 Mixed gas flow path 45 Mixed gas holder 50 Hydrogen purification facility 51 Gas separation device 52 Hydrogen holder 60 Air combustion facility 61 Air blower 70 Waste heat utilization facility 71 First combustion gas flow path 72 Second combustion gas flow path 73 Heat exchanger for steam 74 Heat exchanger for air 75 Air supply line 76 Exhaust gas discharge path 77 Exhaust gas outlet tower 100 Hydrogen production system B Biomass P Organic polymer material C1 Carbide C2 Pyrolysis products other than carbide (decomposition gas, tar, etc.) S Solids (residual carbide and ash) A Air

Claims

1. A method for producing a carbide by carbonizing a raw material containing an organic polymer material and biomass.

2. The production method according to claim 1, wherein the mass ratio of the organic polymer material to the biomass is 0.01 to 99.

3. The production method according to claim 1 or 2, wherein the carbide is for producing a reformed gas containing hydrogen and carbon monoxide.

4. The production method according to claim 3, wherein the biomass contains at least one metal element selected from the group consisting of sodium, potassium, lithium, cesium, calcium, magnesium, strontium, barium, boron, aluminum, iron, titanium, molybdenum, and tungsten.

5. The production method according to claim 4, wherein the content of the metal element is 0.01 to 100 g per 1 kg of the biomass.

6. A carbide production apparatus comprising: a carbonization facility for carbonizing a raw material to obtain a carbide; and a raw material supply facility for supplying a raw material containing an organic polymer material and biomass to the carbonization facility.

7. The carbide production apparatus according to claim 6, wherein the mass ratio of the organic polymer material to the biomass is 0.01 to 99.

8. The carbide production apparatus according to claim 6 or 7, wherein the carbide is for producing a reformed gas containing hydrogen and carbon monoxide.

9. The carbide production apparatus according to claim 8, wherein the biomass contains at least one metal element selected from the group consisting of sodium, potassium, lithium, cesium, calcium, magnesium, strontium, barium, boron, aluminum, iron, titanium, molybdenum, and tungsten.

10. The carbide production apparatus according to claim 9, wherein the content of the metal element is 0.01 to 100 g per 1 kg of the biomass.

11. Producing a carbide by the production method according to claim 1, performing reforming gasification including at least a reaction of the carbide with steam to obtain a reformed gas containing hydrogen and carbon monoxide.

12. The production method according to claim 11, wherein the reforming gasification includes a reaction of the carbide with carbon dioxide.

13. Air-combusting pyrolysis products other than the carbide generated when carbonizing the raw material, and using the exhaust heat of the combustion gas generated by the air-combustion of the pyrolysis products as a heat source in the reforming gasification.

14. The carbide production apparatus according to claim 6, and A reforming gasification facility that performs reforming gasification including at least a reaction of a carbide and steam to obtain a reformed gas containing hydrogen and carbon monoxide, A reformed gas production system comprising:

15. The reformed gas production system according to claim 14, wherein the reforming gasification includes a reaction of the carbide and carbon dioxide.

16. An air combustion facility that air-combusts pyrolysis products other than the carbide produced by the carbide production apparatus, An exhaust heat utilization facility that uses the exhaust heat of the combustion gas generated by the air combustion of the pyrolysis products as a heat source in the reforming gasification facility, The reformed gas production system according to claim 14 or 15, comprising:

17. Producing a reformed gas by the production method according to claim 11, Obtaining a mixed gas containing hydrogen and carbon dioxide at a higher concentration than the reformed gas by a shift reaction of carbon monoxide and steam in the reformed gas, A method for producing hydrogen, comprising performing a hydrogen purification treatment on the mixed gas.

18. Air-combusting pyrolysis products other than the carbide generated when carbonizing the raw material, The production method according to claim 17, wherein the exhaust heat of the combustion gas generated by the air combustion of the pyrolysis products is used as a heat source in the reforming gasification and the shift reaction.

19. The production method according to claim 17 or 18, wherein the shift reaction is performed in the presence of a hydrogenation catalyst.

20. The production method according to claim 19, wherein the hydrogenation catalyst includes at least one element selected from iron, ruthenium, nickel, copper, zinc, chromium, cobalt, molybdenum, zirconia, titanium, cerium, lanthanum, and neodymium, and a porous oxide carrier.

21. The production method according to claim 17 or 18, wherein the hydrogen purification treatment includes a gas separation treatment by either or both of a pressure swing adsorption type gas separation apparatus and a gas separation membrane type gas separation apparatus.

22. The production method according to claim 21, wherein carbon dioxide separated by the gas separation treatment is recovered, and the recovered carbon dioxide is used for the reforming gasification.

23. The reformed gas production system according to claim 14, A mixed gasification facility comprising a shift reactor, and obtaining a mixed gas containing hydrogen and carbon dioxide at a higher concentration than the reformed gas by a shift reaction of carbon monoxide and steam in the reformed gas, A hydrogen purification facility that performs a hydrogen purification treatment on the mixed gas, A hydrogen production system comprising:

24. An air combustion facility for air-combusting pyrolysis products other than the carbide produced in the carbonization facility of the carbide manufacturing apparatus; An exhaust heat utilization facility for utilizing the exhaust heat of the combustion gas generated by the air combustion of the pyrolysis products as a heat source in the reforming gasification facility and the mixed gasification facility; The hydrogen production system according to claim 23, comprising the above.

25. The hydrogen production system according to claim 23 or 24, wherein the shift reactor contains a hydrogenation catalyst.

26. The hydrogen production system according to claim 25, wherein the hydrogenation catalyst contains at least one element selected from iron, ruthenium, nickel, copper, zinc, chromium, cobalt, molybdenum, zirconia, titanium, cerium, lanthanum, and neodymium, and a porous oxide carrier.

27. The hydrogen production system according to claim 23 or 24, wherein the hydrogen purification facility includes one or both of a pressure swing adsorption type gas separation device and a gas separation membrane type gas separation device.

28. The hydrogen production system according to claim 27, wherein the reforming gasification facility is provided with means for recovering carbon dioxide separated by the gas separation device and supplying it to the reforming gasification facility.

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