JP5522646B2 - Combined power generation facility - Google Patents

Description

  The present invention relates to a combined power generation facility in which a fuel cell device that obtains electric power by an electrochemical reaction between hydrogen and oxygen and a gas turbine are combined.

A fuel cell that obtains electric power by an electrochemical reaction between hydrogen and oxygen, for example, a molten carbonate fuel cell (MCFC), for example, has a nickel porous fuel electrode (anode) and a nickel oxide porous material, for example. An electrolyte (carbonate) is sandwiched between the air electrode (cathode). Then, hydrogen (H ₂ ) obtained from a fuel such as natural gas is supplied to the anode, and air (O ₂ ) and carbon dioxide (CO ₂ ) are supplied to the cathode, whereby the electricity of H ₂ and O ₂ is supplied. Electricity is generated by chemical reaction. MCFC operates at a high temperature, has high efficiency, and can recover and separate CO ₂ , so that it has a less environmental impact. For this reason, in recent years, it has attracted attention as a power generation system following hydropower, thermal power, and nuclear power.

  In addition, since the MCFC operates at a high temperature, a combined power generation facility in which the exhaust gas is supplied to the combustor of the gas turbine and the MCFC and the gas turbine are combined has been proposed (for example, patents). Reference 1). By using a combined power generation facility that combines an MCFC and a gas turbine, it is possible to generate power with the MCFC and the gas turbine.

  In fuel cell devices that obtain electric power through an electrochemical reaction between hydrogen and oxygen, such as MCFC, in order to obtain hydrogen as fuel, a fuel gas such as natural gas is sent to the reforming means, and the fuel gas is supplied to the reforming means. Hydrogen is obtained by reforming the fuel gas by introducing about two to three times the steam.

  For example, in the MCFC, the temperature is controlled by circulating the exhaust gas on the cathode side in order to operate in the temperature range where the carbonate is melted. The operating temperature of fuel cells is not limited to MCFC, and the current situation is that temperature control is inevitable. In the case of controlling the temperature by circulating the exhaust gas on the cathode side, particularly in the case of a fuel cell that uses pure oxygen (for example, oxygen of 95% or more) and operates at a stoichiometric ratio with hydrogen, supply oxygen is reduced. Even if it is controlled to a high level, the composition of the circulating cathode gas has an effect, and there is a limit to maintaining high performance of the fuel cell.

  For this reason, fuel cells have been attracting attention as power generation systems that can generate power with high efficiency and have little impact on the environment. However, there are considerable losses to power generation, such as power for temperature control. In addition, there is a limit to maintaining the performance at a high level, and there is a possibility of further improvement in efficiency and performance. This means that efficiency is required regardless of the size of the output. In particular, even if the equipment has a small output, high efficiency and high performance are required. Further, not only in molten carbonate fuel cells (MCFC) but also in power generation facilities to which solid oxide fuel cells (SOFC) are applied, high efficiency and high performance are also demanded.

JP-A-11-135139

  The present invention has been made in view of the above situation, and provides a combined power generation facility that combines a fuel cell facility and a gas turbine capable of achieving high efficiency and high performance while minimizing losses to power generation. The purpose is to do.

A fuel cell facility applied to a combined power generation facility for achieving the above object is supplied with an anode gas containing hydrogen and a cathode gas containing oxygen, and generates electricity by an electrochemical reaction between the anode gas and the cathode gas. A fuel cell to be performed, a reformer provided in the anode gas supply system for reforming the fuel, an endothermic reaction means provided on the anode electrode side of the fuel cell for endothermic reaction of the anode gas, and a cathode gas in the endothermic reaction means adjust the status of the endothermic reaction preferably Rukoto a heat absorbing adjusting means for regulating the operating temperature of the fuel cell.

Thus , the operating temperature is maintained at a predetermined temperature by causing the endothermic reaction of the anode gas by the endothermic adjusting means, and the operating temperature of the fuel cell is controlled to a predetermined state without using power for temperature control.

The fuel cell facility applied to the combined power generation facility is supplied with an anode gas containing hydrogen and a cathode gas containing oxygen, and a fuel cell that generates electricity by an electrochemical reaction between the anode gas and the cathode gas; The reformer for reforming the fuel provided in the anode gas supply system, the endothermic reaction means for the endothermic reaction of the anode gas provided on the anode side of the fuel cell, and the reforming heat source of the reformer are adjusted. Rukoto a reforming conditions adjusting means for adjusting the status of the endothermic reaction means by adjusting the reforming conditions of the fuel regulating the operating temperature of the fuel cell Te is preferred.

As a result, the reforming condition adjusting means adjusts the condition of the reforming heat source of the reformer to adjust the reforming state of the fuel, and the operating temperature is set to a predetermined temperature by causing the adjusted fuel to undergo an endothermic reaction as the anode gas. The operation temperature of the fuel cell is controlled to a predetermined state without using power for temperature control.

The fuel cell facility applied to the combined power generation facility is supplied with an anode gas containing hydrogen and a cathode gas containing oxygen, and a fuel cell that generates electricity by an electrochemical reaction between the anode gas and the cathode gas; A reformer that is provided in the anode gas supply system and reforms the fuel and uses the heat of the exhaust gas of the fuel cell as a reforming heat source, and an endothermic reaction means that is provided on the anode electrode side of the fuel cell and performs an endothermic reaction of the anode gas And reforming to regulate the temperature of the endothermic reaction means and regulate the operating temperature of the fuel cell by adjusting the flow of exhaust gas of the fuel cell, which is the reforming heat source of the reformer, and adjusting the reforming state of the fuel preferably Rukoto a status adjustment unit.

Thereby, the flow of the exhaust gas is adjusted by the reforming condition adjusting means, the reforming heat source condition of the reformer is adjusted to adjust the reforming state of the fuel, and the adjusted fuel is subjected to an endothermic reaction as the anode gas. Thus, the operating temperature is maintained at a predetermined temperature, and the operating temperature of the fuel cell is controlled to a predetermined state without using power for temperature control.

The fuel cell facility applied to the combined power generation facility is supplied with an anode gas containing hydrogen and a cathode gas containing oxygen, and a fuel cell that generates electricity by an electrochemical reaction between the anode gas and the cathode gas; A reformer that is provided in the anode gas supply system and reforms the fuel and uses the heat of the exhaust gas of the fuel cell as a reforming heat source, and an endothermic device by reforming the anode gas that is provided on the anode electrode side of the fuel cell. Adjusting the reforming status of the internal reforming means by adjusting the reforming state of the fuel by adjusting the flow of the exhaust gas of the internal reforming means to be reacted and the fuel cell that is the reforming heat source of the reformer, and the fuel Rukoto a reforming conditions regulating means for regulating the operating temperature of the battery is preferred.

As a result, the flow of exhaust gas is adjusted by the reforming condition adjusting means, the condition of the reforming heat source of the reformer is adjusted to adjust the reforming state of the fuel, and the reformed fuel is internally reformed using the adjusted fuel as the anode gas. The operation temperature is maintained at a predetermined temperature by reforming by means and causing an endothermic reaction, and the operation temperature of the fuel cell is controlled to a predetermined state without using power for temperature control.

The fuel cell facility applied to the combined power generation facility is a second modification that adjusts the reforming status of the internal reforming means by adjusting the fuel reforming state by adjusting the flow of fuel to the reformer. Rukoto with the quality status adjusting means are preferred.

As a result, the flow of the fuel to the reformer is further adjusted by the second reforming state adjusting means, and the reformed state including the flow rate is adjusted.

The fuel cell facility applied to the combined power generation facility is supplied with pure oxygen at a predetermined pressure as the cathode gas of the fuel cell, and the fuel cell is operated with a ratio of hydrogen and oxygen supplied at a predetermined stoichiometric ratio. It is preferable.

As a result, oxygen in an equivalent ratio to the fuel is supplied, and a stoichiometric operation in which the ratio of hydrogen to oxygen becomes a predetermined stoichiometric ratio is performed.

Further, in the fuel cell facility applied to the combined power generation facility, it is preferable that pure oxygen at a predetermined pressure is oxygen in a pressurized state produced by concentrating nitrogen gas by pressure swing adsorption and removing it from the air .

Thereby, the oxygen of a pressurization state can be obtained easily and it is not necessary to provide the equipment which pressurizes oxygen.

Further, the fuel cell equipment applied to the combined power generation equipment is preferably a molten carbonate fuel cell that generates power by an electrochemical reaction of an anode gas containing hydrogen and a cathode gas containing oxygen .

Thereby, it can be set as the fuel cell equipment provided with the molten carbonate fuel cell.

In order to achieve the above object, the combined power generation facility of the present invention according to claim 1 is supplied with an anode gas containing hydrogen and a cathode gas containing oxygen, and generates electricity by an electrochemical reaction between the anode gas and the cathode gas. A fuel cell, a combustor in which exhaust gas of the fuel cell is introduced and combusted, a gas turbine that expands the combustion gas from the combustor, and an anode gas supply system that reforms the fuel and gas A reformer that uses the heat of the exhaust gas of the turbine as a heat source for reforming, an internal reforming means that is provided on the anode electrode side of the fuel cell and performs an endothermic reaction by reforming the anode gas, and heats the exhaust gas of the gas turbine a preheating means for performing preheating of the cathode gas recovered, the exhaust gas of a gas turbine is modified heat source of the reformer, the heat source circulation amount to the reformer, result adjustment at the outlet side of the reformer , The exhaust gas of a gas turbine, a heat source flow rate of the preheating means, to adjust the outlet side of the pre-heating means, the reforming of internal reforming means by adjusting the reforming conditions of the fuel reformer The reforming status adjusting means that regulates and regulates the operating temperature of the fuel cell, and the reforming status of the internal reforming means is adjusted by adjusting the amount of fuel flowing to the reformer and adjusting the reforming state of the fuel And a second reforming state adjusting means.

In the present invention according to claim 1, the reforming condition adjusting means adjusts the heat source circulation amount of the exhaust gas of the gas turbine to the reformer and the heat source circulation amount to the preheating means, and the reforming heat source of the reformer is adjusted. By adjusting the situation and adjusting the reforming state of the fuel, the adjusted fuel is reformed by the internal reforming means as an anode gas, and the endothermic reaction is performed to maintain the operating temperature at a predetermined temperature, and the power for temperature control is increased. It can be set as the combined electric power generation equipment provided with the fuel cell which can control operation temperature to a predetermined state, and a gas turbine, without using.
And it is set as the combined power generation equipment provided with the fuel cell which can adjust the reforming state including the circulation amount by further adjusting the flow amount of the fuel to the reformer by the second reforming state adjusting means. Can do.

According to a second aspect of the present invention, there is provided the combined power generation facility according to the first aspect, wherein pure oxygen at a predetermined pressure is supplied as the cathode gas of the fuel cell, and the ratio of hydrogen to oxygen is a predetermined amount. The fuel cell is operated by being supplied at a stoichiometric ratio.

The present invention according to claim 2 is a combined power generation facility including a fuel cell in which oxygen in an equivalent ratio to fuel is supplied and a stoichiometric operation is performed in which the ratio of hydrogen to oxygen becomes a predetermined stoichiometric ratio. be able to.

According to a third aspect of the present invention, there is provided the combined power generation facility according to the first or second aspect , wherein the pure oxygen at a predetermined pressure is removed from the air by concentrating nitrogen gas by pressure swing adsorption. It is the oxygen of the pressurized state manufactured by being manufactured.

According to the third aspect of the present invention, it is possible to obtain a combined power generation facility including a fuel cell that can easily obtain pressurized oxygen and does not need to include a facility for pressurizing oxygen.

A combined power generation facility according to a fourth aspect of the present invention is the combined power generation facility according to any one of the first to third aspects, wherein the fuel cell includes an anode gas containing hydrogen, oxygen, and carbon dioxide. a molten carbonate fuel cell which generates power by an electrochemical reaction of the cathode gas containing, comprising a circulation system for mixing carbon dioxide of the exhaust gas of the gas turbine to the cathode gas, the circulation system, from the exhaust gas of the gas turbine A separation means for obtaining carbon dioxide is provided.

In the present invention according to claim 4 , by supplying only oxygen in an equivalent ratio to the fuel, the total amount of carbon dioxide generated with power generation can be recovered to obtain carbon dioxide at a high concentration as an oxidant for the cathode gas. It is possible to construct a closed cycle system that can be used, and it is possible to provide a combined power generation facility that can achieve high efficiency at a high level.

In order to achieve the above object, the combined power generation facility of the present invention according to claim 5 is a molten carbonate fuel cell that generates power by an electrochemical reaction of an anode gas containing hydrogen and a cathode gas containing oxygen and carbon dioxide, A combustor in which exhaust gas from a molten carbonate fuel cell is introduced and combusted, a gas turbine that expands the combustion gas from the combustor, and an anode gas supply system provided with a bypass flow path are provided and bypassed. The amount of fuel in the flow path is adjusted and the fuel is sent to reform the fuel and to the reformer that uses the heat of the exhaust gas from the gas turbine as the heat source for reforming and to the anode side of the molten carbonate fuel cell and internal reforming means for endothermic reaction by reforming the anode gas provided, comprising a circulation system for mixing carbon dioxide of the exhaust gas of the gas turbine to the cathode gas, the circulation lines, the gas turbine A preheating means for performing preheating of the cathode gas vapor gas and heat recovery, the circulation system for circulating exhaust gas of the gas turbine to the reformer, the heat source distribution of the exhaust gas of the gas turbine to the path and distribution system of the preheating means By adjusting the amount and adjusting the reforming state in the reformer, the reforming status of the anode gas is adjusted, and the reforming status of the internal reforming means is controlled to control the operating temperature of the molten carbonate fuel cell. The reforming condition adjusting means to regulate, the preheating means, the separation means for obtaining carbon dioxide from the exhaust gas of the gas turbine that has circulated through the distribution system, and the pressurization for pressurizing and mixing the carbon dioxide separated by the separation means with the cathode gas Means.

In the present invention according to claim 5, the heat source circulation amount of the exhaust gas of the gas turbine is adjusted by the reforming state adjusting means, the state of the reforming heat source of the reformer is adjusted to adjust the reforming state of the fuel, The adjusted fuel is reformed by the internal reforming means as an anode gas, and the operation temperature is maintained at a predetermined temperature by an endothermic reaction, and the operation temperature is controlled to a predetermined state without using power for temperature control. This is a combined power generation facility equipped with a molten carbonate fuel cell that can be used to recover all the carbon dioxide generated during power generation by supplying only oxygen in an equivalent ratio to the fuel and use carbon dioxide as an oxidant for the cathode gas. It is possible to construct a closed cycle system that can be obtained at a high concentration, and it is possible to provide a combined power generation facility that can achieve high efficiency at a high level.

And the combined power generation facility of the present invention according to claim 6 is the combined power generation facility according to claim 5 , wherein the state of reforming of the internal reforming means is controlled by adjusting the flow state of the anode gas to the reformer. An anode gas flow adjusting means is provided.

In the present invention according to claim 6 , it is possible to control the temperature of the molten carbonate fuel cell by adjusting the flow state to the reformer and adjusting the reforming state of the internal reforming means.

The combined power generation facility according to the present invention according to claim 7 is the combined power generation facility according to claim 5 or 6 , wherein the pressurizing means is a carbon dioxide compressor and melts at the outlet side of the carbon dioxide compressor. A molten carbonate fuel cell is operated by supplying pure oxygen at a predetermined pressure as a cathode gas of the carbonate fuel cell and supplying a ratio of hydrogen and oxygen at a predetermined stoichiometric ratio.

In the present invention according to claim 7 , it is possible to construct a closed cycle system by including a compressor that compresses only carbon dioxide.

The combined power generation facility of the present invention according to claim 8 is the combined power generation facility according to claim 5 or 6 , wherein the pressurizing means is an oxygen / carbon dioxide compressor, At the inlet side, normal pressure pure oxygen is supplied as the cathode gas of the molten carbonate fuel cell, and the molten carbonate fuel cell is operated with the ratio of hydrogen and oxygen supplied at a predetermined stoichiometric ratio. And

In the present invention according to claim 8 , it is possible to construct a closed cycle system by including a compressor for compressing supplied pure oxygen.

  The combined power generation facility of the present invention can be a combined power generation facility that combines a fuel cell facility and a gas turbine that can achieve high efficiency and high performance while minimizing losses to power generation.

1 is a schematic system diagram of a combined power generation facility according to a first embodiment of the present invention. It is a schematic system diagram of the combined power generation facility according to the second embodiment of the present invention. It is a schematic system diagram of the combined power generation facility according to the third embodiment of the present invention. It is a schematic system diagram of the combined power generation facility according to the fourth embodiment of the present invention.

  1 is a schematic system of a combined power generation facility according to a first embodiment of the present invention, FIG. 2 is a schematic system of a combined power generation facility according to a second embodiment of the present invention, and FIG. FIG. 4 shows a schematic system of a combined power generation facility according to a fourth embodiment of the present invention.

  A first embodiment will be described with reference to FIG.

  As shown in FIG. 1, the combined power generation facility 1 of the present embodiment is provided with a molten carbonate fuel cell (MCFC) 2, and combustion in which outlet gas (exhaust gas) of the MCFC 2 is introduced and combustion is performed. A vessel 3 is provided. A gas turbine 4 that expands and drives the combustion gas from the combustor 3 is provided, and the gas turbine 4 is provided with a generator 5 coaxially. The generator 5 is operated by driving the gas turbine 4 to generate power. Reference numeral 6 in the figure is a mixer provided on the upstream side of the combustor 3 to prevent backfire.

The MCFC 2 is configured, for example, by sandwiching an electrolyte (carbonate) between a fuel electrode (anode) 7 of a nickel porous body and an air electrode (cathode) 8 of a nickel oxide porous body, for example. . Then, hydrogen (H ₂ ) obtained from the fuel f such as natural gas is supplied to the anode 7, and air (O ₂ ) and CO ₂ are supplied to the cathode 8, whereby the H ₂ and O ₂ electrochemistry is obtained. Electricity is generated by the reaction.

  Downstream of the gas turbine 4, a reformer 9 and a cathode gas preheater 10 that perform heat recovery of exhaust gas that has finished work in the gas turbine 4 are provided in parallel, and the reformer 9 and the cathode gas preheater 10 A steam generator 11 is provided on the downstream side. The steam generated by the steam generator 11 is supplied to the fuel f as steam for reforming.

The exhaust gas heat recovered by the steam generator 11 is separated into condensed water (H ₂ O) and non-condensed gas (CO ₂ ) by the drain separation cooler 12. The CO ₂ separated by the drain separation cooler 12 is compressed by the CO ₂ compressor 13, mixed with the pressurized O ₂ and sent to the cathode gas preheater 10 (circulation system). A mixed gas (cathode gas) of O ₂ and CO ₂ preheated by the cathode gas preheater 10 is supplied to the cathode 8 of the MCFC ₂ .

The fuel f (for example, methane) is sent to the reformer 9 from a supply path 14 as a supply system, and is reformed by the reformer 9 to be an anode gas (an anode gas containing H ₂ ). The anode gas reformed by the reformer 9 is supplied to the anode 7 of the MCFC 2.

O ₂ to CO ₂ is mixed compressed in the CO ₂ compressor 13, nitrogen gas is concentrated by pressure swing adsorption is a O ₂ under pressure produced is removed from the air, for example, oxygen The composition is 95% and nitrogen is 5%. For this reason, O ₂ in a pressurized state can be easily obtained, and the CO ₂ compressor 13 that compresses only CO ₂ by the compressor provided in the circulation system can be obtained. Since a compressed fluid is specified by using a compressor that compresses only CO ₂ , the compressor can be easily designed with blades and the like.

  On the other hand, the anode 7 of the MCFC 2 is provided with an internal reforming means 15 as an endothermic reaction means, and the anode gas is reformed by the internal reforming means 15 to cause an endothermic reaction. Although details will be described later, the operating temperature of the MCFC 2 is regulated by reforming the anode gas by the internal reforming means 15 and causing an endothermic reaction. In order to regulate the operating temperature of the MCFC 2, the reforming status of the anode gas reformed by the internal reforming means 15 is adjusted (endothermic adjusting means).

  That is, the temperature of the reformer 9 is adjusted by adjusting the flow of the exhaust gas of the gas turbine 4 that is the reforming heat source of the reformer 9, and the reformed state of the fuel f is adjusted (for example, the reformer The reforming rate at 9 is lowered: reforming condition adjusting means). Further, the flow rate of the fuel f to the reformer 9 is adjusted to adjust the flow rate, and the reforming status of the internal reforming means 15 is adjusted (for example, the reforming rate in the reformer 9 is lowered). : Second reforming adjusting means).

  The reforming condition adjusting means will be described.

  A reforming passage 16 is provided for flowing the exhaust gas to the reformer 9 provided on the exhaust side of the gas turbine 4, and the exhaust gas is supplied to the cathode gas preheater 10 provided on the exhaust side of the gas turbine 4. A preheating flow path 17 is provided. The reforming channel 16 and the preheating channel 17 are joined upstream of the steam generator 11. In addition, a bypass flow path 18 is provided to join the exhaust gas of the gas turbine 4 directly upstream of the steam generator 11.

  A reforming flow rate adjusting valve 19 is provided in the reforming flow path 16 on the downstream side of the reformer 9, and a preheating flow rate adjusting valve 20 is provided in the preheating flow path 17 on the downstream side of the cathode gas preheater 10. . By controlling the opening degree of the reforming flow rate adjusting valve 19 and the preheating flow rate adjusting valve 20, the exhaust gas flow rate of the gas turbine 4 to the reforming channel 16, the preheating channel 17, and the bypass channel 18 is controlled. The reformed state of the fuel f is adjusted by adjusting the flow rate of the exhaust gas that becomes the heat source of the mass device 9.

  The second reforming adjusting means will be described.

  A bypass channel 21 that does not flow through the reformer 9 is provided in the fuel f supply system, and the amount of fuel f that flows through the reformer 9, that is, the reforming amount of the fuel f, is adjusted in the bypass channel 21. A flow rate adjustment valve 22 is provided. The amount of the heat source of the reformer 9 is adjusted by adjusting the reforming flow rate adjusting valve 19 and the preheating flow rate adjusting valve 20, and the flow rate adjusting valve 22 is adjusted so that the fuel f corresponding to the amount of heat flows. As a result, the reforming rate in the reformer 9 is reduced, and the anode gas is reformed by that amount by the internal reforming means 15 to cause an endothermic reaction, thereby controlling the operating temperature of the MCFC 2.

In the combined power generation facility 1 described above, the exhaust gas of the MCFC 2 is completely combusted by the combustor 3 to drive the gas turbine 4, and the heat of the exhaust gas of the gas turbine 4 is recovered (gas preheating, reforming heat source, etc.) And is separated into condensed water (H ₂ O) and non-condensed gas (CO ₂ ) by the drain separation cooler 12. Among these, H ₂ O generated by the cell reaction and combustion is discharged out of the system, and CO ₂ is pressurized and circulated as a cathode gas.

For this reason, by supplying only O _{2 in an} equivalent ratio to the fuel f and performing stoichiometric ratio operation, the entire amount of CO ₂ generated during power generation is recovered, and CO ₂ is used as a cathode gas oxidant in a high concentration. It is possible to construct a closed-cycle system that can be obtained, and the combined power generation facility 1 that can achieve high efficiency at a high level can be obtained. Further, the anode gas and the cathode gas can be appropriately heated using the heat of the exhaust gas of the gas turbine 4.

  Then, the flow of the exhaust gas from the gas turbine 4 is adjusted by adjusting the reforming flow rate adjusting valve 19 and the preheating flow rate adjusting valve 20, and the state of the reforming heat source of the reformer 9 is adjusted to change the reforming state of the fuel f. The fuel f that has been adjusted and whose reformed state has been adjusted is reformed by the internal reforming means 15 as an anode gas and subjected to an endothermic reaction. The operation temperature of the MCFC 2 is maintained at a predetermined temperature by the endothermic reaction, and the operation temperature of the MCFC 2 can be controlled to a predetermined state without using power for temperature control.

Incidentally, when power for temperature control is used, it is conceivable to control the temperature of the MCFC 2 by circulating the exhaust gas of the cathode 8 using a blower. At this time, the exhaust gas after cooling is merged with the cathode gas and supplied to the cathode 8, but other than O ₂ (for example, nitrogen) is accumulated by the circulation of the exhaust gas, and has an equivalent ratio to the fuel f. Although it is a facility that operates stoichiometrically with O ₂ , power generation efficiency is reduced. For this reason, as in the present embodiment example, pressurized O ₂ gas (a small amount of cathode gas containing nitrogen) produced by concentrating nitrogen gas by pressure swing adsorption and removing it from the air is used. And there is a possibility that the ratio of O ₂ is relatively lowered and the power generation efficiency is significantly reduced.

In the combined power generation facility 1 described above, the operating temperature of the MCFC 2 is maintained at a predetermined temperature by the endothermic reaction, and the operating temperature of the MCFC 2 is set to the predetermined temperature without using power for temperature control such that the exhaust gas of the cathode 8 is circulated by the blower. Since the temperature can be controlled, power for temperature control becomes unnecessary, and there is no problem of a relative decrease in the O ₂ ratio, and high efficiency can be maintained. Then, the operating temperature of the MCFC 2 can be controlled by controlling the openings of the reforming flow rate adjusting valve 19, the preheating flow rate adjusting valve 20, and the flow rate adjusting valve 22 provided in the flow path through which the low temperature gas flows. The operation temperature of the MCFC 2 can be controlled without using an expensive high temperature compatible valve. In addition, since pressurized O ₂ produced by concentrating nitrogen gas by pressure swing adsorption and removed from the air is used, pressurized oxygen can be easily obtained, and equipment for pressurizing oxygen can be installed. There is no need to prepare.

Accordingly, power for temperature control is not required, and the combined power generation facility 1 having the MCFC 2 capable of maintaining high efficiency is obtained, and CO ₂ generated by power generation by supplying only O ₂ with an equivalent ratio to the fuel. It is possible to construct a closed cycle system that can collect CO2 at a high concentration as an oxidant for cathode gas by collecting the total amount of CO ₂ and can achieve high efficiency at a high level. It becomes. For this reason, it can be set as the combined power generation equipment 1 which combined MCFC2 and the gas turbine 4 which can aim at efficiency improvement and high performance in a high dimension, suppressing the loss with respect to electric power generation as much as possible.

In the above-described embodiment, the example in which pressurized O ₂ produced by concentrating nitrogen gas by pressure swing adsorption and removing it from the air has been described. The manufactured pure O ₂ can be separately pressurized and supplied.

  A second embodiment will be described with reference to FIG.

The combined power generation facility 31 of the second embodiment supplies normal pressure pure O ₂ to the combined power generation facility 1 of the first embodiment, and compresses it with the recovered CO ₂ to form a cathode gas. . For this reason, the same code | symbol is attached | subjected to the same member as the structural member of the combined power generation equipment 1 of 1st Embodiment, and the overlapping description is abbreviate | omitted.

Instead of the CO ₂ compressor 13 (see FIG. 1) of the first embodiment, as shown in FIG. 2, a compressor 32 is provided between the drain separation cooler 12 and the cathode gas preheater 10. ing. The compressor 32 compresses a mixed gas of CO ₂ and O ₂ , is preheated by the cathode gas preheater 10 as a cathode gas, and is supplied to the cathode 8 of the MCFC 2. The inlet side of the compressor 32 is supplied with, for example, pure O _{2 at} normal pressure manufactured by a deep cooling facility, and CO ₂ recovered by the drain separation cooler 12 is mixed.

The combined power generation facility 31 of the second embodiment is similar to the combined power generation facility 1 of the first embodiment, and the combined power generation facility including the MCFC 2 that can maintain high efficiency because power for temperature control becomes unnecessary. 31 is a closed cycle system that recovers the entire amount of CO ₂ generated by power generation by supplying only O _{2 in an} equivalent ratio to the fuel, and can obtain CO ₂ at a high concentration as an oxidant of the cathode gas. It becomes possible to construct the combined power generation facility 31 that can achieve high efficiency in a high dimension. For this reason, it can be set as the combined power generation equipment 31 which combined MCFC2 and the gas turbine 4 which can aim at efficiency improvement and performance improvement in a high dimension, suppressing the loss with respect to electric power generation as much as possible.

Then, it is possible to compress the pure O ₂ at atmospheric pressure, it can be supplied O ₂ very high purity produced in cryogenic equipment. For this reason, O ₂ having an equivalent ratio to the fuel can be stably supplied, and highly efficient power generation can be stably performed.

  A third embodiment of the present invention will be described based on FIG.

The combined power generation facility 35 of the third embodiment is obtained by applying an oxide solid oxide fuel cell (SOFC) instead of the MCFC 2 to the combined power generation facility 1 of the first embodiment, and is normally used as a cathode gas. The pressure O ₂ is applied. In addition, instead of a closed cycle in which CO ₂ is circulated, the SOFC internal reforming means 39 is used as a function similar to the internal reforming means 15 of the first embodiment. For this reason, the same code | symbol is attached | subjected to the same member as the structural member of the combined power generation equipment 1 of 1st Embodiment, and the overlapping description is abbreviate | omitted.

Instead of the MCFC 2 (see FIG. 1) of the first embodiment, an oxide solid oxide fuel cell (SOFC) 36 is provided as shown in FIG. The SOFC 36 includes an air electrode (cathode) 37 and a fuel electrode (anode) 38 to which fuel is supplied. The anode 38 is provided with an internal reforming means 39 as an endothermic reaction means. The CO ₂ compressor 13 (see FIG. 1) in the first embodiment is not provided, and the gas separated by the drain separation cooler is discharged (collected) to the outside.

The cathode 37 of the SOFC 36 is supplied with O ₂ preheated to a predetermined temperature by the cathode gas preheater 10, and the anode 38 of the SOFC 36 is supplied with the fuel f reformed by the reformer 9 (the flow of the bypass passage 21 is adjusted). The supplied fuel f is supplied to generate power, and the anode 38 reforms the fuel f by the internal reforming means 39 (endothermic reaction), and adjusts the temperature of the SOFC 36.

  Similar to the combined power generation facility 1 of the first embodiment, the combined power generation facility 35 of the third embodiment is a combined power generation facility 35 that does not require power for temperature control, and achieves higher dimensions and higher efficiency. The combined power generation facility 35 can be obtained. For this reason, it is possible to provide a combined power generation facility 35 that combines the SOFC 36 and the gas turbine 4, which can suppress loss to power generation as much as possible and achieve higher efficiency and higher performance in a higher dimension.

  A fourth embodiment of the present invention will be described based on FIG.

  As shown in FIG. 4, the combined power generation facility 41 of the present embodiment is provided with a molten carbonate fuel cell (MCFC) 42, and a part of the outlet gas (exhaust gas) of the MCFC 42 is introduced for combustion. A combustor 43 is provided to be performed. Further, a gas turbine equipment 47 having a compressor 44 that compresses air, a combustor 45 that combusts compressed air and fuel f, and a turbine 46 that expands combustion gas from the combustor 45 and generates electric power is provided. . A part of the exhaust gas of the MCFC 42 is mixed with the combustion gas expanded by the turbine 46 of the gas turbine equipment 47.

  Reference numeral 48 in the figure denotes a mixer provided on the upstream side of the combustor 43 to prevent backfire, 49 a motor / generator for starting the gas turbine equipment 47, and 50 a compressor at the start. This is a start combustor in which a part of the air compressed in 44 and fuel are introduced to generate combustion gas and mix it with the exhaust gas of MCFC42.

The MCFC 42 is configured, for example, by sandwiching an electrolyte (carbonate) between a fuel electrode (anode) 51 of a nickel porous body and an air electrode (cathode) 52 of a nickel oxide porous body, for example. . Then, hydrogen (H ₂ ) obtained from the fuel f such as natural gas is supplied to the anode 51, and the air compressed by the compressor 44 is supplied to the cathode 52, whereby the H ₂ and O ₂ electrochemistry is supplied. Electricity is generated by the reaction.

  The fuel f is preheated by the anode gas preheater 53, reformed by the reformer 54, recovered by the anode gas preheater 53, and supplied to the anode 51. The exhaust gas of the MCFC 42 is mixed by the mixer 48, burned by the combustor 43, recovered as heat as a heat source of the reformer 54, and then pumped to the cathode 52 by the blower 55.

  On the other hand, a part of the exhaust gas of the cathode 52 is merged with the combustion gas of the combustor 45 of the gas turbine equipment 47 and expanded by the turbine 46, and the exhaust gas of the turbine 46 is recovered by the steam generator 56. The exhaust gas heat-recovered by the steam generator 56 is condensed by the condenser 57, and the condensed water is supplied to the steam generator 56 by the feed water pump and the exhaust gas is released.

  The anode 51 of the MCFC 42 is provided with an internal reforming means 61 as an endothermic reaction means, and the anode gas is reformed by the internal reforming means 61 to cause an endothermic reaction. Although details will be described later, the operating temperature of the MCFC 42 is regulated by reforming the anode gas by the internal reforming means 61 and causing an endothermic reaction. In order to regulate the operating temperature of the MCFC 42, the reforming status of the anode gas reformed by the internal reforming means 61 is adjusted (endothermic adjusting means).

  That is, the temperature of the reformer 54 is adjusted by adjusting the flow of the combustion gas from the combustor 43 that is the reforming heat source of the reformer 54, and the reformed state of the fuel f is adjusted (for example, reforming). The reforming rate in the vessel 54 is reduced: reforming condition adjusting means). Further, the flow rate of the fuel f to the reformer 54 is adjusted to adjust the flow rate, and the reforming status of the internal reforming means 61 is adjusted (for example, the reforming rate in the reformer 54 is reduced). : Second reforming adjusting means).

  The reforming condition adjusting means will be described.

  A reforming channel 62 for allowing combustion gas to flow through the reformer 54 provided on the downstream side of the combustor 43 is provided, and a bypass channel 63 for bypassing the reformer 54 is provided. A combustion gas flow rate adjustment valve 64 is provided on the front side of the junction with the bypass flow path 63 on the downstream side of the reformer 54. The flow rate of the combustion gas of the combustor 43 to the reforming flow path 62 and the bypass flow path 63 is controlled by adjusting the opening of the combustion gas flow rate adjusting valve 64, and the combustion gas flow rate serving as the heat source of the reformer 54 is changed. The reformed state of the fuel f is adjusted by adjusting.

  The second reforming adjusting means will be described.

  In the fuel f supply system, the anode gas preheater 53 is circulated to flow the fuel f to the reformer 54, and the anode gas preheater 53 is bypassed to flow the fuel f to the reformer 54. A bypass flow passage 66 and a fuel supply passage 67 for directly supplying the fuel f to the anode 51 of the MCFC 42 are provided. A three-way valve 68 is provided at a branch portion of the flow passage 65, the bypass flow passage 66, and the fuel supply passage 67, and the flow passage 65, the bypass flow passage 66, and the fuel supply passage 67 are adjusted by adjusting the opening state of the three-way valve 68. The amount of fuel f supplied to the fuel, that is, the amount of reforming of fuel f can be adjusted.

  The amount of heat source of the reformer 54 is adjusted by the reforming state adjusting means and the second reforming adjusting means, and the fuel f corresponding to the amount of heat flows through the reformer 54. As a result, the reforming rate in the reformer 54 is reduced, and the anode gas is reformed by that amount by the internal reforming means 61 to cause an endothermic reaction, and the operating temperature of the MCFC 42 can be regulated.

  In the combined power generation facility 41 described above, the combustion gas flow rate of the combustor 43 is adjusted by adjusting the combustion gas flow rate adjustment valve 64 to adjust the state of the reforming heat source of the reformer 54, and the fuel f is adjusted by adjusting the three-way valve 68. The reforming amount of the fuel f is adjusted to adjust the reforming state of the fuel f. Then, the reformed state of the fuel f is reformed by the internal reforming means 61 as an anode gas to cause an endothermic reaction. The operation temperature of the MCFC 42 is maintained at a predetermined temperature by the endothermic reaction, and the operation temperature of the MCFC 42 can be controlled to a predetermined state without using power for temperature control in a facility provided with a gas turbine facility 47 that burns compressed air. it can.

  Accordingly, the power for temperature control becomes very small, and the combined power generation facility 41 having the MCFC 42 capable of maintaining high efficiency is obtained, and the facility having the gas turbine facility 47 for combusting the compressed air is improved in high dimension and high efficiency. Thus, the combined power generation facility 41 can be achieved.

The present invention can be utilized in the industrial fields of electrochemical reactions combined cycle facility that combines fuel cell apparatus and the gas turbine for obtaining power by the hydrogen and oxygen.

1, 31, 35, 41 Combined power generation facility 2, 42 Molten carbonate fuel cell (MCFC)
3, 43, 45 Combustor 4 Gas turbine 5 Generator 6, 48 Mixer 7, 38, 51 Fuel electrode (anode)
8, 37, 52 Air electrode (cathode)
9, 54 Reformer 10 Cathode gas preheater 11, 56 Steam generator 12 Drain separation cooler 13 CO ₂ compressor 15, 39, 61 Internal reforming means 16, 62 Reform channel 17 Preheat channel 18 Bypass flow Path 19 Reformation flow rate adjustment valve 20 Preheating flow rate adjustment valve 21, 63 Bypass flow path 22 Flow rate adjustment valve 32, 44 Compressor 36 Oxide solid oxide fuel cell (SOFC)
46 Turbine 47 Gas Turbine Equipment 49 Motor / Generator 50 Start Combustor 55 Blower 57 Condenser 64 Combustion Gas Flow Rate Adjustment Valve 65 Flow Path 66 Bypass Flow Path 67 Fuel Supply Path 68 Three-way Valve

Claims (8)

A fuel cell that is supplied with an anode gas containing hydrogen and a cathode gas containing oxygen, and generates electricity by an electrochemical reaction between the anode gas and the cathode gas;
A combustor in which the exhaust gas of the fuel cell is introduced and burned,
A gas turbine for expanding the combustion gas from the combustor;
A reformer provided in an anode gas supply system for reforming fuel and using the heat of the exhaust gas of the gas turbine as a reforming heat source;
An internal reforming means provided on the anode electrode side of the fuel cell and performing an endothermic reaction by reforming the anode gas;
Preheating means for recovering heat from the exhaust gas of the gas turbine and preheating the cathode gas;
While adjusting the amount of heat source flow of the gas turbine exhaust gas, which is the reforming heat source of the reformer, to the reformer on the outlet side of the reformer, the heat source flow of the gas turbine exhaust gas to the preheating means the amount and adjusted at the outlet side of the preheating means, the reforming conditions regulating means for regulating the operating temperature of the adjusted fuel cell reforming of internal reforming means by adjusting the reforming conditions of the fuel reformer When,
And a second reforming state adjusting unit that adjusts the reforming state of the internal reforming unit by adjusting the amount of fuel flowing to the reformer to adjust the reforming state of the fuel. Combined power generation facilities. The combined power generation facility according to claim 1,
A combined power generation facility, wherein pure oxygen at a predetermined pressure is supplied as a cathode gas of a fuel cell, and a fuel cell is operated with a ratio of hydrogen and oxygen supplied at a predetermined stoichiometric ratio. In the combined power generation facility according to claim 1 or 2,
Pure oxygen at a predetermined pressure is pressurized oxygen produced by concentrating nitrogen gas by pressure swing adsorption and removing it from the air. In the combined power generation facility according to any one of claims 1 to 3,
The fuel cell is a molten carbonate fuel cell that generates electricity by an electrochemical reaction of an anode gas containing hydrogen and a cathode gas containing oxygen and carbon dioxide.
It has a circulation system that mixes carbon dioxide in the exhaust gas of the gas turbine with the cathode gas,
A combined cycle power generation facility characterized in that the circulation system is provided with separation means for obtaining carbon dioxide from the exhaust gas of the gas turbine . A molten carbonate fuel cell that generates electricity by an electrochemical reaction of an anode gas containing hydrogen and a cathode gas containing oxygen and carbon dioxide;
A combustor in which exhaust gas from a molten carbonate fuel cell is introduced and burned,
A gas turbine for expanding the combustion gas from the combustor;
Provided in an anode gas supply system provided with a bypass channel, the amount of fuel in the bypass channel is adjusted and fuel is sent to reform the fuel, and the heat of the exhaust gas of the gas turbine is used as a reforming heat source. A reformer to
An internal reforming means provided on the anode electrode side of the molten carbonate fuel cell and performing an endothermic reaction by reforming the anode gas;
It has a circulation system that mixes carbon dioxide in the exhaust gas of the gas turbine with the cathode gas,
The circulation system is
Preheating means for recovering heat from the exhaust gas of the gas turbine and preheating the cathode gas;
A distribution system for distributing the exhaust gas of the gas turbine to the reformer;
The reforming state of the anode gas is adjusted by adjusting the reforming state in the reformer by adjusting the route of the preheating means and the heat source circulation amount of the exhaust gas of the gas turbine to the distribution system, and the internal reforming means A reforming condition adjusting means for controlling the reforming condition to regulate the operating temperature of the molten carbonate fuel cell;
Separation means for obtaining carbon dioxide from the exhaust gas of the gas turbine that has circulated through the preheating means and the distribution system;
And a pressurizing unit that pressurizes the carbon dioxide separated by the separating unit and mixes it with the cathode gas. In the combined power generation facility according to claim 5,
A combined power generation facility comprising anode gas flow adjusting means for controlling a reforming state of internal reforming means by adjusting a flow state of anode gas to a reformer. In the combined power generation facility according to claim 5 or 6,
The pressurizing means is a carbon dioxide compressor, pure oxygen at a predetermined pressure is supplied as the cathode gas of the molten carbonate fuel cell at the outlet side of the carbon dioxide compressor, and the ratio of hydrogen to oxygen is a predetermined stoichiometric ratio. A combined power generation facility characterized in that a molten carbonate fuel cell is supplied and operated. In the combined power generation facility according to claim 5 or 6,
The pressurizing means is an oxygen / carbon dioxide compressor. At the inlet side of the oxygen / carbon dioxide compressor, normal pressure pure oxygen is supplied as the cathode gas of the molten carbonate fuel cell, and the ratio of hydrogen to oxygen is predetermined. A combined power generation facility characterized in that a molten carbonate fuel cell is operated in a stoichiometric ratio.

Images