JP6229115B2 - Power generation apparatus and power generation method - Google Patents

Description

  The present invention relates to a power generation device that combines a gasification furnace using a carbon-based fuel as a raw material and a fuel cell, and more particularly to a highly efficient power generation device and a power generation method.

  In recent years, in consideration of the environment, it has been proposed to use a fuel cell as a power source or power generation equipment for a vehicle such as an automobile or a train (for example, Patent Document 1). A fuel cell is a power generator that can continuously extract electric power by supplying hydrogen and oxygen from the outside to a negative electrode and a positive electrode, respectively, and reacting them. On the other hand, the primary battery and the secondary battery have a limited electric capacity because the reducing agent and the oxidizing agent are filled in the electrodes in the battery. On the other hand, since the fuel cell supplies the reducing agent and the oxidizing agent from the outside, the fuel cell has a great feature in that the electric capacity is not limited and power generation can be continuously performed.

  The fuel cell is characterized in that there is no combustion process in the power generation process, and hydrogen and oxygen react to generate water, so that it is said to be a power generation device with a low environmental load.

  Patent Document 2 discloses a fuel cell combined cycle power generation system including a fluidized bed gas furnace and a fuel cell. That is, the fuel supplied to the fluidized bed gas furnace undergoes thermal decomposition in a high temperature range, and generates a gas containing carbon monoxide and hydrogen which is an effective gas component for fuel cell power generation. In this case, the temperature rise from the temperature at the time of fuel injection to a high temperature range is performed by partially burning the fuel. Ashes and the like are removed from the produced gas from the fluidized bed gas furnace by a dust collector, hydrogen gas is produced in the reactor, and is sent to the fuel cell to generate electricity.

  In Patent Document 3, hydrogen is generated from a fluidized bed gas furnace that gasifies a raw material containing carbon, a fuel cell installed in the fluidized bed gas furnace, and a product gas gasified in the fluidized bed gas furnace. There is disclosed a gasification facility having a shift reactor, in which the fuel cell generates electricity using hydrogen generated in the shift reactor.

  In Patent Document 4, gasified gas generated in a coal gasification furnace is reformed into hydrogen gas in a shift reactor and supplied to a fuel cell for power generation, and supplied to a gas turbine for power generation. Technology is disclosed.

JP 2006-092920 A International Publication No. 2000/027951 International Publication No. 2013/005699 JP 2008-291081 A

  Although the fuel cell is excellent in environmental resistance, the heat generated during power generation from the fuel cell is not recovered as motive power and is not necessarily effectively used.

  According to the power generation device disclosed in Patent Document 3, since the fuel cell is installed in the fluidized bed gas furnace, heat generated during power generation from the fuel cell is effectively used, but is included in the raw material. It cannot be said that the carbon content is sufficiently utilized, and the conversion rate to hydrogen is not sufficient. That is, gas or the like discharged from the shift reactor contains carbon or hydrocarbons, and carbon is not effectively converted and recovered.

Further, according to the gasification facility disclosed in Patent Document 4, when the hydrogen gas generated in the shift reactor is supplied to the fuel cell, a tar content remains in the gas discharged from the shift reactor. The tar content not only adversely affects the operation of the fuel cell, but also may damage the fuel cell.
Furthermore, when tar adheres to carbon or hydrocarbon, there is also a problem that the shift reaction is difficult to proceed.

  An object of the present invention is to solve the above-described problems, and is to provide a power generation device with high power generation efficiency by converting exergy ΔG to electrical energy as much as possible. Another purpose is to effectively use resources by increasing the conversion rate of carbon contained in the raw material into hydrogen. Furthermore, the tar content prevents the operation of the fuel cell from being hindered or damaged.

  In order to achieve the above-described object, a power generation apparatus according to the present invention includes a pyrolysis furnace that heats and thermally decomposes a raw material containing carbon and / or hydrocarbons, and discharges pyrolysis gas and first solids. A fluidized bed gas furnace for pyrolyzing the first solid material to generate a first product gas; a combustion furnace for heating the second solid material from the fluidized bed gas furnace to generate a second product gas; A power generator comprising: a shift reactor that generates hydrogen from the pyrolysis gas and the first product gas; and a fuel cell that generates power using the hydrogen generated in the shift reactor, wherein the fuel cell It is installed in the bed gas furnace.

  In this configuration, carbon, hydrocarbons, a mixture of carbon and hydrocarbons, biomass, livestock manure, and the like can be considered as raw materials supplied to the pyrolysis furnace. The raw material is a carbon source and a reducing material. The raw material is preferably fed into the pyrolysis furnace from a hopper or the like. And the pyrolysis gas which is gas, and the 1st solid substance which is solid are discharged | emitted from a pyrolysis furnace. Hydrogen is produced from the pyrolysis gas in a shift reactor. The first solid is supplied to a fluidized bed gas furnace to generate a first product gas.

  In the power generation apparatus according to the present invention, the second product gas is preferably supplied to the pyrolysis furnace. According to this configuration, since carbon undergoes thermal decomposition in the combustion furnace and the pyrolysis furnace, the conversion efficiency of carbon into hydrogen is improved.

In the power generation apparatus according to the present invention, it is preferable that a tar decomposition apparatus for decomposing a tar content contained in the pyrolysis gas and the first product gas is installed on the upstream side of the shift reactor.
According to this configuration, since the tar content is removed from the hydrogen supplied to the fuel cell, the operation of the fuel cell is hindered and is not damaged.

  In the power generation apparatus according to the present invention, a material seal is provided between the combustion furnace and the fluidized bed gas furnace, so that air and water vapor supplied to the combustion furnace do not flow to the fluidized bed gas furnace. ing. According to this configuration, air or the like supplied to the combustion furnace does not flow backward to the fluidized bed gas furnace.

  In the power generation apparatus according to the present invention, the fluidized bed gas furnace is provided with a fluidized bed, and further, a dispersion plate is provided under the fluidized bed, and the fuel cell is disposed in the fluidized bed. Therefore, it is preferable to be disposed above the dispersion plate.

  According to this configuration, the fluidized bed is filled with the fluidized medium, and the fluidized medium is held by the dispersion plate. Thereby, a fuel cell is arrange | positioned at the fluidized bed which is a component of a fluidized bed gas furnace. In the fluidized bed, solid particles made of sand of an appropriate size are arranged as a fluidized medium. By blowing gas from the lower part of the fluidized bed, the fluidized medium is floated to a certain height and is in a state of moving violently.

  The power generation apparatus according to the present invention preferably uses heat generated by power generation of the fuel cell as heat necessary for pyrolyzing the first solid matter in the fluidized bed gas furnace.

  According to this configuration, since the fuel cell is installed in the fluidized bed, the heat generated by the fuel cell during the reaction (power generation) is directly transferred to the fluidized bed through the fluidized medium without waste, and effectively the fluidized bed. The heat required for gasification of the first solid in the gas furnace is supplied.

  The feature of the present invention is that the heat required for gasification of the first solid does not use the heat generated by the combustion of the first solid, but uses the heat generated by the reaction (power generation) of the fuel cell.

  In the power generation apparatus according to the present invention, steam generated during power generation of the fuel cell is supplied to a wind box disposed upstream of the dispersion plate. According to this configuration, there is a wind box at the bottom of the fluidized bed gas furnace, and steam necessary for fluidizing the fluidized medium is blown into the fluidized bed from the wind box. In addition, water vapor is used as a gas for floating suspension of the fluidized bed, and air is not used.

In a general fluidized bed gas furnace, by blowing air from a wind box at the bottom of the furnace, a fluid medium such as high-temperature sand is fluidized with hot air in the bed, and the raw materials are pyrolyzed therein. Gasification is performed. When air is sent into the fluidized bed by a blower or the like, the raw material is burned by oxygen contained in the air. If a combustion process is involved in power generation, exergy loss occurs and the exergy rate ΔG / ΔH is reduced. If air is used for fluidization, nitrogen is also heated. However, in the fluidized bed gas furnace in the power generator according to the present invention, the fluidization uses steam generated by the reaction (power generation) of the fuel cell. Since air is not taken in from the outside for fluidization, a decrease in the value of the exergy rate ΔG / ΔH can be prevented. As a result, the power generation efficiency becomes the exergy rate ΔG / ΔH, which is the theoretical efficiency. Combustion means a wide combustion process including partial combustion. By using high-pressure steam, the fluidized bed gas furnace and the pressure downstream thereof can be kept high.

  In the power generation device according to the present invention, it is preferable that hydrogen from the shift reactor is supplied to the fuel cell.

  The shift reactor uses the heat of water vapor to generate hydrogen from the product gas. Here, the shift reactor reforms the product gas to produce hydrogen to be supplied to the fuel cell. Here, reforming is to produce hydrogen from carbon monoxide in the product gas. Usually, steam is supplied as a heat source, and the shift reaction proceeds with the help of a catalyst.

According to this configuration, the fuel cell generates high-temperature water vapor during power generation. By utilizing this water vapor for the gasification reaction and shift reaction, the heat generated by the fuel cell can be used effectively without wasting it. Here, the shift reaction is represented by the formula (1). On the other hand, the gasification reaction is expressed by equation (2).
CO + H ₂ O = CO ₂ + H ₂ (1)
C + 2H ₂ O═CO ₂ + 2H ₂ (2)

  The cogeneration power generation system according to the present invention includes a pyrolysis furnace that heats and pyrolyzes a raw material containing carbon and / or hydrocarbons to discharge a pyrolysis gas and a first solid, and the first solid A fluidized bed gas furnace that pyrolyzes to generate a first product gas, a combustion furnace that heats a second solid material from the fluidized bed gas furnace to generate a second product gas, the pyrolysis gas, and the A hydrogen cogeneration system having a shift reactor for generating hydrogen from a first product gas and a fuel cell installed in the fluidized bed gas furnace, wherein a part of the hydrogen is supplied to the fuel cell To generate electricity.

  The power generation method according to the present invention includes a raw material pyrolysis step in which a raw material containing carbon and / or hydrocarbon and a second product gas are heated to discharge a pyrolysis gas and a first solid, and the first solid A fluidized bed gasification step for thermally decomposing the first product gas; and a heating and combustion step for generating a second product gas by introducing the second solid matter from the fluidized bed gas furnace to a combustion furnace and heating it; A tar removal step of separating and removing a tar component by heating the first product gas and the pyrolysis gas; a shift reaction step of generating hydrogen by a shift reaction of the gas discharged from the tar decomposition step; and the shift reaction And supplying the hydrogen generated in the step to the fuel cell to generate electricity. According to this method, the fuel cell is installed in the fluidized bed. The raw material in the raw material pyrolysis step contains carbon and / or hydrocarbon.

  The power generation method according to the present invention includes a raw material pyrolysis step in which a raw material containing carbon and / or hydrocarbon and a second product gas are heated to discharge a pyrolysis gas and a first solid, and the first solid A fluidized bed gasification step for thermally decomposing the first product gas; and a heating and combustion step for generating a second product gas by introducing the second solid matter from the fluidized bed gas furnace to a combustion furnace and heating it; A tar removal step of separating and removing a tar component by heating the first product gas and the pyrolysis gas; a shift reaction step of generating hydrogen by a shift reaction of the gas discharged from the tar decomposition step; and the shift reaction The hydrogen generated in the step is supplied to the fuel cell to generate electric power, and the hydrogen that is not supplied to the fuel cell is extracted from the hydrogen generated in the shift reaction step. Having. According to this method, a part of the hydrogen generated in the fluidized bed gas furnace and the shift reactor is supplied to the fuel cell to generate power, and the remaining hydrogen can be taken out as a product. It can be called a power generation method.

  By using the heat generated by the fuel cell power generation as the heat necessary for the gasification and reforming reaction of the raw material, it is possible to provide a power generation device with high power generation efficiency. Further, since the carbon source is gasified in the fluidized bed gas furnace, the combustion furnace, and the pyrolysis furnace, gasification with high conversion efficiency is possible. Furthermore, by removing the tar content from the gas, the gasification reaction can be facilitated and damage to the fuel cell can be prevented.

It is a basic lineblock diagram of the power generator concerning an embodiment of the present invention. It is a figure which shows the mass balance of carbon in a basic block diagram. It is a flow sheet of the power generator concerning an embodiment of the present invention. (A) is a flow sheet which concerns on embodiment which drives a steam turbine with the steam which generate | occur | produced in the fuel cell, (b) is a flow sheet which concerns on embodiment of FIG. It is a schematic block diagram of a coal gasification fuel cell power generator.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments.

  FIG. 1 is a diagram showing a basic configuration of a power generator according to an embodiment of the present invention. The fluidized bed gas furnace 8 has a wind box 3 serving as a working gas intake port, a fluidized bed 2 positioned above the wind box 3, and a free board portion 7 positioned above the fluidized bed 2 as main components. doing. The wind box 3 and the fluidized bed 2 are partitioned by a dispersion plate 4.

The raw material G, which is a solid fuel, is charged into the pyrolysis furnace 16 together with the steam S1 from the raw material charging unit 15 located at the top of the pyrolysis furnace 16. The water vapor is a supply source of water (H ₂ O) for generating hydrogen. The raw material G may be carbon, hydrocarbon, organic matter, and a mixture thereof. Although coal is used in this embodiment, fossil fuels and biomass other than coal may be used. It may be methanol and ethanol, or may be a polymer compound such as plastic. Edible oil or heavy oil may be used.

  Gases and solids carried from the combustion furnace 12 are supplied from the upper part of the pyrolysis furnace 16. The pyrolysis furnace 16 forms a moving bed, and the solid material such as the raw material G supplied from the raw material input unit 15, the carbon sent to the combustion furnace 12, the fluidized medium 5, and ash is affected by gravity. , Descend in the pyrolysis furnace 16.

  The raw material G and the carbon from the combustion furnace 12 are pyrolyzed by being heated in the pyrolysis furnace 16 by the heat from the steam S1 and the combustion furnace 12 in the descending process, and the solid content and the gas content. Divided into The former contains carbon, which is a fixed carbon, and the latter contains tar and hydrocarbons. Both are separated into a solid matter (first solid matter) which is a solid content and a pyrolysis gas which is a gas content by a separation unit 17 disposed at the outlet of the combustion furnace 12, and the former is sent to a fluidized bed gas furnace 8. The latter is sent to the tar decomposition apparatus 21. As a result, the first solid does not contain a tar content.

The reaction in the pyrolysis furnace 16 is a reforming reaction represented by the formula (2 ′), and generates carbon dioxide and hydrogen from carbon and water. At this time, the heat (Q) required for the reaction uses the heat supplied from the fuel cell 6.
Q + C + 2H ₂ O → CO ₂ + 2H ₂ (2 ′)

The solids sent from the pyrolysis furnace 16 to the fluidized bed gas furnace 8 contain carbon, fluidized medium 5 and ash, etc., of which carbon is in the temperature range of 900 ° C. to 1000 ° C. in the fluidized bed 2. It undergoes thermal decomposition at, and is reduced with water to produce hydrogen. The reaction formula is shown in Formula (3).
_{C + H 2 O = CO +} H 2 (3)
Among these, hydrogen becomes an effective gas component for power generation by the fuel cell 6. At this time, the temperature of the fluidized bed 2 is maintained using heat generated by the reaction (power generation) of the fuel cell 6. Incombustible materials and ash mixed in the raw material G are discharged from the fluidized bed 2.
At the time of gasification in the fluidized bed gas furnace 8, if the tar adheres to the solid matter, the gasification reaction is hindered. However, since the tar content is separated by the pyrolysis furnace 16 and the tar content hardly adheres to the solid matter, the gasification reaction is not inhibited by the tar.

  Since the gasification reaction is a reduction, heat is required for the reaction, and the heat is supplied from the fuel cell 6 installed in the fluid medium 5. The fuel cell 6 is preferably one that operates at a high temperature because it serves as a heat source for gasification. Specifically, a solid oxide fuel cell (SOFC) that requires an operating temperature of 800 to 1,000 ° C. is preferable.

  The water vapor S2 from the fuel cell 6 is fed into the wind box 3, and the fluid medium 5 made of solid particles is suspended and suspended on the dispersion plate 4 to be fluidized. The fluid medium 5 is a granular material such as silica sand, alumina or iron particles, or a mixture thereof. Further, the fluid medium 5 may carry a catalyst for producing water by reducing water. Examples of these catalysts include ash, sodium, potassium, and calcium. Alumina may be supported on the fluid medium 5. The fluidized medium 5 has a function of transferring heat to carbon in the fluidized bed 2.

  The gas gasified in the fluidized bed 2 (hereinafter referred to as the first product gas) contains carbon dioxide, water vapor, carbon monoxide, hydrogen, dust, and hydrocarbons. The first product gas is sent from the upper part of the fluidized bed gas furnace 8 to the tar decomposition apparatus 21. The first product gas contains some tar.

  In the downstream part of the fluidized bed 2, that is, the free board part 7, the pyrolysis endothermic reaction proceeds, so that the gas temperature is lower than that of the fluidized bed part. For example, even if the fluidized bed temperature is 950 ° C., the gas temperature in the free board part 7 may be lower than 650 ° C. When the gas temperature is 400 ° C. or lower, air or oxygen may be supplied to the free board part 7 to avoid a tar trouble, thereby increasing the gas temperature.

  A delivery pipe 9 is connected to the lower part of the fluidized bed 2, so that the fluidized medium 5 and the powder of carbon mixed therein are sent to the combustion furnace 12. Here, the carbon content is the carbon content (char) that has not been processed in the fluidized bed gas furnace 8. In addition, the fluidized medium 5 plays a role of supplying heat downstream as sensible heat having a heat capacity while supplying the catalyst downstream. An air and water vapor supply port 13 is provided in the lower part of the combustion furnace 12, and the powder sent from the fluidized bed 2 is suspended and suspended in the combustion furnace 12. The combustion furnace 12 forms a circulating fluidized bed.

  At this time, water vapor supplies water necessary for the gasification reaction, and air reacts (combusts) with the carbon in the powder, thereby contributing to maintaining the temperature in the combustion furnace 12 at a high temperature. That is, carbon contained in the powder is partially burned to become carbon monoxide and heat. Heat is used for a gasification reaction in the combustion furnace 12, and carbon monoxide reacts with water vapor to generate carbon dioxide and hydrogen.

  The carbon contained in the powder undergoes thermal decomposition in the temperature range from 400 ° C to 1000 ° C to produce a gas containing hydrogen, carbon monoxide, and some hydrocarbons (hereinafter referred to as the second product gas). To do. A material seal 11 is disposed between the fluidized bed gas furnace 8 and the combustion furnace 12, and air and water vapor supplied from the supply port 13 are blocked by the material seal 11 and do not flow back to the fluidized bed 2. It is like that.

  When air flows backward from the supply port 13 to the fluidized bed 2, carbon is combusted by oxygen contained in the air, resulting in a decrease in the exergy rate ΔG / ΔH. Also, nitrogen contained in the air is heated. The material seal 11 makes it possible to achieve high thermal efficiency in the fluidized bed 2.

  A collecting pipe 14 is provided in the upper part of the combustion furnace 12 so that the second product gas from the combustion furnace 12 flows into the collecting pipe 14. The second product gas is a fluid in which powder and gas containing carbon dioxide, water vapor, carbon monoxide, hydrogen, nitrogen, fluid medium 5, unburned carbon, and dust are mixed. Carbon dioxide and nitrogen in the inflowing second product gas are discarded out of the system from the collecting pipe 14 as exhaust gas WG. The second product gas from which the exhaust gas WG has been removed is sent to the pyrolysis furnace 16 from the top of the pyrolysis furnace 16.

  The raw material G and the water vapor S1 input from the raw material input unit 15 are thermally decomposed into a solid content and a gas content while descending in the pyrolysis furnace 16. The separation unit 17 plays a role of separating the solid content and the gas content. Solid matter, which is a solid content in the gas discharged from the collecting pipe 15, is sent into the fluidized bed gas furnace 8, and the pyrolysis gas, which is a gas content, flows to the tar decomposition device 21. The pyrolysis gas contains a small amount of fluid medium 5 in addition to tar mainly composed of hydrocarbons.

  Since tar is separated upstream of the fluidized bed gas furnace 8, the reaction (formula (3)) in the fluidized bed gas furnace 8 is not inhibited by the tar. In addition, the carbon in the raw material G circulates in the fluidized bed gas furnace 8 → the combustion furnace 12 → the fluidized bed gas furnace 8, thereby improving the conversion rate of carbon contained in the raw material into hydrogen. It was.

  The pyrolysis gas and the first product gas are heated by the tar decomposition device 21, decomposed into carbon monoxide and hydrogen, and sent to the next-stage gas cleaning device 22.

  The product gas made from biomass and waste contains various unspecified impurities such as tar, dioxin, heavy metals, light metals, and acid gases. In the tar cracking device 21, the pyrolysis gas and the first product gas are circulated through a honeycomb passage carrying a high-temperature nickel-based or cobalt-based catalyst, so that tar, aromatic hydrocarbons and the like that are pyrolyzable impurities Organochlorine compounds such as unsaturated hydrocarbons and dioxins are removed by thermal decomposition.

The gas sent to the gas cleaning device 22 (hereinafter referred to as tar-free gas; TF gas) is at a temperature of approximately 400 ° C. to 650 ° C. at the inlet of the gas cleaning device 22.
As the gas cleaning device 22, a cyclone method can be used, but a filter method may be adopted. The filter method is preferable from the viewpoint of high dust collection. In the temperature range of 400 ° C. to 650 ° C., a bag filter can be used as the gas cleaning device 22, but a cyclone may be used and a ceramic filter may be further arranged downstream thereof. Here, dust and tar content are removed.

  Solids such as ash and alkali metal salts removed by the gas cleaning device 22 are discharged out of the system through a discharge path (not shown). The TF gas from which ash or the like has been removed is sent to the shift reactor 23. A corrosive gas removal device (not shown) for removing a corrosive gas such as hydrogen chloride or hydrogen sulfide contained in the TF gas may be provided between the gas cleaning device 22 and the shift reactor 23.

A catalyst for increasing the reaction rate, for example, magnetite (Fe ₃ O ₄ ), platinum, or the like, is filled in the pipe inside the shift reactor 23 and through which the TF gas flows. High-temperature steam generated by the reaction (power generation) in the fuel cell 6 may be supplied to the shift reactor 23. Using the moisture contained in the high-temperature steam, the shift reactor 23 reacts carbon monoxide in the TF gas with water to generate hydrogen. This reaction formula is shown in Formula (4).
CO + H ₂ O → H ₂ + CO ₂ (4)

  The gas component (pyrolysis gas) in the pyrolysis furnace 16 is sucked by the IDF 24 installed downstream of the shift reactor 23 and sent to the shift reactor 23 via the tar cracking device 21.

  The TF gas treated in the shift reactor 23 passes through the IDF 24, and the carbon dioxide is separated and removed by the CO2 separation device 25 in the next stage, and the carbon dioxide is discharged out of the system. Hydrogen is sent to the hydrogen separator 26 in the next stage.

  In the hydrogen separator 26, the hydrogen gas is separated from the water vapor and supplied to the anode (negative electrode) of the fuel cell 6 via the fuel tank 27. Since the hydrogen gas supplied to the fuel cell 6 does not contain tar, the tar prevents the operation of the fuel cell 6 from being damaged. On the other hand, the steam is supplied from the wind box 3 of the fluidized bed gas furnace 8 to the fluidized bed 2 and contributes to fluidization of the fluidized medium 5.

  Although oxygen gas is also supplied to the fuel cell 6, the fuel gas (oxygen and hydrogen) supplied to the fuel cell 6 is rich in hydrogen, so that unreacted hydrogen gas and Water vapor generated by the reaction is included. The exhaust gas of the fuel cell 6 flows to the hydrogen separator 26, where the hydrogen gas is separated and contributes to the power generation of the fuel cell 6 as described above.

  Since the heat generated from the fuel cell 6 is almost equal to the endothermic component of the gasification reaction, this heat can be used as a heat source for gasification in the fluidized bed gas furnace 8. Thereby, in the fluidized bed gas furnace 8, gasification can be performed without partial combustion of carbon, so that power generation with high energy efficiency can be achieved.

  The cogeneration power generation system heats and pyrolyzes a raw material containing carbon and / or hydrocarbons, and pyrolyzes the pyrolysis gas and the first solid matter, and pyrolyzes the first solid matter. The fluidized bed gas furnace 8 for generating the first generated gas, the combustion furnace 12 for heating the second solid matter from the fluidized bed gas furnace 8 to generate the second generated gas, the pyrolysis gas and the first generated gas The shift reactor 23 for generating hydrogen from the fuel cell 6 and the fuel cell 6 installed in the fluidized bed gas furnace 8 are provided. A part of the hydrogen from the hydrogen separator 26 is supplied to the fuel cell to generate electric power, and the hydrogen stored in the hydrogen tank 27 can be supplied to other facilities.

  FIG. 2 shows the mass balance in the basic configuration diagram. Assuming that the carbon of the solid fuel charged from the raw material charging unit 15 is 100 moles (C: 100), 30 moles of carbon flow to the tar cracking device 21 and 70 moles of carbon flow to the fluidized gas furnace 8. The fluidized bed 2 is supplied with 200 mol of water vapor. In the combustion furnace 12, 200 moles of hydrogen are produced by the gasification reaction. From the shift reactor 23, 100 mol of carbon dioxide and 200 mol of hydrogen are discharged. Then, the carbon dioxide separator 25 separates 100 moles of carbon dioxide and 200 moles of hydrogen. 200 mol of water vapor from the fuel cell 6 and 200 mol of hydrogen from the carbon dioxide separator 25 are separated and discharged by the hydrogen separator 26 into 200 mol of water vapor and 200 mol of hydrogen.

  FIG. 3 (a) shows a flow sheet of power-heat cogeneration that produces both power and heat. FIG. 3 (b) shows a flow sheet of a power-hydrogen co-production that produces both power and hydrogen. The numerical values in the figure indicate the energy at each stage when the energy of coal is 100, and the numerical values in parentheses indicate the energy ratio and the exergy ratio. In the power-heat cogeneration (FIG. 3A), 11% of the energy is exhausted. On the other hand, the power-hydrogen co-production (FIG. 3B) does not have such energy loss. The power-hydrogen co-production system may be referred to as a co-hydrogen power generation system.

  Since the Industrial Revolution, electrical energy, kinetic energy, potential energy, etc. have been extracted by converting coal, oil, biomass, sunlight, and nuclear energy into heat. Since electric energy, kinetic energy, potential energy, and the like can be converted into each other, they are expressed here as electric energy. Thermal energy has been extracted from external combustion engines such as steam engines and Stirling engines, gas turbine engines, diesel engines, and spark ignition engines. Fuel cells have also been associated with the generation of heat when hydrogen is converted into electrical energy.

  In the above power generation method, heat is always generated, and cogeneration for use as heat is performed, or a heat engine having a lower temperature level is operated using the generated heat. Further, effective use of primary energy has been attempted, for example, by regenerating heat by exchanging the generated heat with combustion air.

  This type of power generating device generates heat by exchanging heat and transferring it to fuel and air, or by installing a heat engine that operates in a lower temperature range to use heat as a cascade. Although it has been devised to generate, it is not enough.

  When the load changes, the amount of power generation is changed by changing the fuel supply amount. By performing air-fuel ratio control that controls the amount of air with respect to the fuel, the exhaust gas loss is made constant. However, a boiler turbine generator with a 100% load and a power generation efficiency of 40% has a power generation efficiency of about 30% at a load of 33%.

  When hydrogen is converted into electrical energy using a fuel cell, 17% of the heat generated by hydrogen is generated as heat. If hydrogen is produced by reducing water with coal, petroleum, biomass, or natural gas using this heat, heat generation can be suppressed and power generation efficiency can be increased.

  When hydrogen is converted into electrical energy using a fuel cell, 17% of the heat generated by hydrogen is generated as heat. In order to reduce the amount of heat generated, high-pressure hydrogen is sent to the fuel cell and hydrogen is produced, so that heat generation can be suppressed and power generation efficiency can be increased.

  When hydrogen is produced from electrical energy using a fuel cell, heat of 17% of the calorific value of hydrogen is required. At that time, if hydrogen and oxygen are generated at normal pressure, it will work against the atmosphere, resulting in loss. Become. Therefore, electrolysis is performed in a sealed space, and TΔS of 17% can be reduced.

  The power generation efficiency of the partial combustion gasification fuel cell combined power generation so far calculated 70%, but the power generation apparatus according to the present invention performs gasification using the heat generated by the fuel cell, thereby generating power efficiency. Increases to 89%.

FIG. 4 is a schematic configuration diagram in which a fluidized bed furnace, shift reactor, and fuel cell, which play a central role in the embodiment of the present invention, are extracted. In FIG. 4, coal is introduced into a high temperature fluidized bed to reduce water vapor and generate hydrogen and carbon monoxide. Since carbon monoxide reacts with water to form hydrogen and carbon dioxide, equation (5) is obtained as a whole.
C + 2H ₂ O + Q = CO ₂ + 2H ₂ (5)

Here, Q indicates the amount of heat necessary for the reaction, and is supplied by the amount of heat generated from the fuel cell installed in the fluidized bed. In the fuel cell, the reaction of the formula (6) occurs.
_{2H 2 + O 2 = 2H 2} O + Q + W (6)

Here, Q indicates the amount of heat generated by power generation, and is the same value as the amount of heat when carbon is gasified. W is electrical energy. When these two expressions are added together, expression (7) is obtained, and carbon reacts with oxygen and is converted into carbon dioxide and electric energy.
_{C + O 2 = CO 2 +} W (7)

  The power generator according to the present invention can be suitably used as a power generator in a power plant of a commercial power system. Moreover, it can be used suitably also as a power generator in a private power generation facility or a power generator connected to a microgrid.

G Raw material S Water vapor 2 Fluidized bed 3 Wind box 4 Dispersion plate 5 Fluidized medium 6 Fuel cell 7 Free board part 8 Fluidized bed gas furnace 9 Delivery pipe 11 Material seal 12 Combustion furnace 13 Supply port 14 Collecting pipe 15 Raw material input part 16 Thermal decomposition Furnace 17 Separation part 21 Tar decomposition device 22 Gas cleaning device 23 Shift reactor 24 IDF
25 Carbon dioxide separator 26 Hydrogen separator 27 Hydrogen tank 30 Fuel cell power generation

Claims (10)

A pyrolysis furnace for heating and pyrolyzing a raw material containing carbon and / or hydrocarbons to discharge pyrolysis gas and first solids;
A fluidized bed gas furnace for pyrolyzing the first solid to generate a first product gas;
A combustion furnace for heating the second solid matter from the fluidized bed gas furnace to produce a second product gas;
A shift reactor for generating hydrogen from the pyrolysis gas and the first product gas;
A tar cracking device installed on the upstream side of the shift reactor and cracking a tar content contained in the pyrolysis gas and the first product gas;
A power generating apparatus having a fuel cell which generates electric power by using hydrogen generated in the shift reactor,
A power generator in which the fuel cell is installed in the fluidized bed gas furnace.   The power generation apparatus according to claim 1, wherein the second product gas is supplied to the pyrolysis furnace. The have material seal is provided between the combustion furnace and the fluidized bed gas furnace, air and water vapor is supplied to the combustion furnace according to claim 2 which is prevented from flowing into the fluidized bed gas furnace Power generation device. The fluidized bed gas furnace is provided with a fluidized bed, and further, a dispersion plate is provided under the fluidized bed,
The power generator according to any one of claims 1 to 3 , wherein the fuel cell is disposed in the fluidized bed and above the dispersion plate. The power generation apparatus according to any one of claims 1 to 3 , wherein in the fluidized bed gas furnace, heat generated by power generation of the fuel cell is used as heat necessary for thermally decomposing the first solid matter. The power generation apparatus according to any one of claims 1 to 3 , wherein steam generated during power generation of the fuel cell is supplied to a wind box disposed upstream of the dispersion plate. The power generator according to any one of claims 1 to 3 , wherein hydrogen from the shift reactor is supplied to the fuel cell. A pyrolysis furnace for heating and pyrolyzing a raw material containing carbon and / or hydrocarbons to discharge pyrolysis gas and first solids;
A fluidized bed gas furnace for pyrolyzing the first solid to generate a first product gas;
A combustion furnace for heating the second solid matter from the fluidized bed gas furnace to produce a second product gas;
A shift reactor for generating hydrogen from the pyrolysis gas and the first product gas;
A tar cracking device installed on the upstream side of the shift reactor and cracking a tar content contained in the pyrolysis gas and the first product gas;
A hydrogen cogeneration system having a fuel cell installed in the fluidized bed gas furnace,
A hydrogen cogeneration system that generates electricity by supplying a part of the hydrogen to the fuel cell. A raw material pyrolysis step of heating the raw material containing carbon and / or hydrocarbon and the second product gas to discharge the pyrolysis gas and the first solid;
A fluidized bed gasification step of pyrolyzing the first solid to generate a first product gas;
A heating and combustion step in which the second solid matter from the fluidized bed gasification step is led to a combustion furnace and heated to generate a second product gas;
A tar content removing step of separating and removing the tar content by heating the first product gas and the pyrolysis gas;
A shift reaction step for generating hydrogen by a shift reaction of the gas discharged from the tar decomposition step;
And a step of generating electricity by supplying the hydrogen produced in the shift reaction step to a fuel cell. A raw material pyrolysis step of heating the raw material containing carbon and / or hydrocarbon and the second product gas to discharge the pyrolysis gas and the first solid;
A fluidized bed gasification step of pyrolyzing the first solid to generate a first product gas;
A heating and combustion step in which the second solid matter from the fluidized bed gasification step is led to a combustion furnace and heated to generate a second product gas;
A tar content removing step of separating and removing the tar content by heating the first product gas and the pyrolysis gas;
A shift reaction step for generating hydrogen by a shift reaction of the gas discharged from the tar decomposition step;
Supplying hydrogen generated in the shift reaction step to a fuel cell to generate electric power, and extracting hydrogen not supplied to the fuel cell from the hydrogen generated in the shift reaction step. Power generation method.

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