JP2018190605A - Power generation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generation system capable of supplying electric power at a low cost.SOLUTION: The power generation system includes: a LPG charging station (a LPG supply facility) 1 having a LPG storage part 10 for storing LPG and distribution equipment (a LPG distribution part) 30 for distributing LPG stored in the LPG storage part 10 to a predetermined container (a LPG cylinder) 50; a power generator 20 installed at the LPG charging station 1 and generating electricity at a power generation efficiency of at least 30% LHV with LPG of LPG storage part 10 as a fuel.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a power generation system that generates power using LPG (Liquefied Petroleum Gas) as a fuel.

  In recent years, fuel cells have attracted attention as clean power generation systems that do not emit air pollutants from the viewpoint of environmental problems. Fuel cells can be used in various fields, and are conventionally installed in ordinary houses and condominiums (household fuel cells). Some of these household fuel cells use LPG as fuel.

  A household fuel cell in which LPG is used is composed of a power generation unit and a hot water storage unit. The power generation unit generates power by taking out hydrogen from the LPG and reacting it with oxygen in the air, and can make hot water using the heat generated at that time. Also, the hot water storage unit can store hot water made by the power generation unit.

  In addition, a consumer who owns a household fuel cell in which LPG is used purchases an LPG cylinder from a sales office (a supplier that sells LPG to the consumer), so that electric power and hot water can be obtained from the above-mentioned household fuel cell. Can be generated. When the LPG in the purchased LPG cylinder is consumed and emptied, the emptied cylinder (used cylinder) is collected by the sales office and returned to the LPG filling station. The returned cylinder is filled with LPG at the LPG filling station, delivered to the sales office as a delivery cylinder, and the consumer purchases it again. Such an LPG supply system has been conventionally proposed (for example, Patent Document 1).

JP 2007-194143 A

  However, in the prior art described in Patent Document 1, a consumer who owns a household fuel cell in which LPG is used can obtain the power from the cost of introducing the above-mentioned household fuel cell or from the sales office. There is a disadvantage that it costs to purchase an LPG cylinder.

  Then, an object of this invention is to provide the electric power generation system which can supply electric power at low cost in view of the said subject.

  In order to solve the above problems, an electric power generation system of the present invention includes an LPG supply facility including an LPG storage unit that stores LPG, and an LPG distribution unit that distributes LPG of the LPG storage unit to a predetermined container, A generator that is provided in an LPG supply facility and that uses LPG in the LPG storage unit as fuel and generates electricity with a power generation efficiency of 30% LHV or more.

  The generator may be a fuel cell.

  The generator may be a fuel recycling type fuel cell.

  The generator may be a fuel recyclable fuel cell.

  The generator may be a gas engine.

  ADVANTAGE OF THE INVENTION According to this invention, the electric power generation system which can supply electric power at low cost can be provided.

It is the schematic of the LPG filling place in 1st Embodiment. It is a schematic block diagram of a generator (fuel recycling regeneration type fuel cell). It is the schematic of the LPG stand in 2nd Embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(First embodiment)
FIG. 1 is a schematic view of an LPG filling station 1 according to the first embodiment. The LPG filling station is a base having a distribution facility for distributing LPG from an LPG storage unit to a predetermined container. In this embodiment, the LPG filling station (LPG supply facility) 1 includes an LPG storage unit 10 that stores LPG, and a distribution facility (LPG distribution unit) that distributes the LPG of the LPG storage unit 10 to a predetermined container (LPG cylinder) 50. 30).

  For example, LPG imported from overseas is first stored in an import base (primary base). There are 35 import bases nationwide. The LPG stored in the import base is transported to a relay base (secondary base) having a large tank for temporarily storing the LPG. There are, for example, 50 relay bases nationwide. The LPG stored in the relay base is transported from the relay base to the LPG filling station (tertiary base) 1 in each region via the tank lorry T. The LPG filling station 1 is installed in, for example, 2200 places nationwide.

  As shown in FIG. 1, the tank truck T filled with LPG transports LPG from the relay station to the LPG filling station 1. When the tank truck T arrives at the LPG filling station 1, the tank truck T transfers the LPG to the LPG storage unit 10 of the LPG filling station 1. Thereby, the LPG storage unit 10 is filled with LPG. The distribution facility 30 includes a pipe 31 connected to the LPG storage unit 10 and distributes the LPG from the LPG storage unit 10 to a predetermined container (LPG cylinder) 50 for delivering the LPG to a sales office. The distribution facility 30 includes a plurality of supply ports 31 a and 31 b provided at the tip of the pipe 31. The plurality of supply ports 31a and 31b are configured to be detachable from a predetermined container 50, respectively. When the container 50 is attached to each of the plurality of supply ports 31a and 31b, the distribution facility 30 can simultaneously distribute (fill) the LPG in the LPG storage unit 10 to the plurality of containers 50.

  The container 50 filled with LPG is delivered to the sales office as a delivery cylinder, and the delivered container 50 is sold to the consumer from the sales office. A consumer who has purchased the container 50 can use the LPG filled in the container 50 as fuel for cooking, hot water supply, leisure or household fuel cells in the consumer premises.

  As described above, in the LPG filling station 1, the LPG in the LPG storage unit 10 has been used for the purpose of filling the container 50. Therefore, even when the LPG in the LPG storage unit 10 is distributed to the containers 50 that are delivered to the sales office, there are many cases where the LPG remains in the LPG storage unit 10. In such a case, the LPG remaining in the LPG storage unit 10 without being distributed to the container 50 is stored in the LPG storage unit 10 without being used until the next time it is distributed to the container 50. Therefore, the LPG remaining in the LPG storage unit 10 cannot be effectively used only by using the LPG in the LPG storage unit 10 for the purpose of filling the container 50.

  Therefore, the LPG filling station 1 in the present embodiment includes a generator 20 that generates electricity (electric power) using the LPG of the LPG storage unit 10 as fuel. In this way, by installing the generator 20 in the LPG filling station 1 so that electricity can be generated, LPG that has remained only by distribution to the container 50 can be effectively used.

  The generator 20 provided in the LPG filling station 1 is a generator having a power generation efficiency of 30% LHV or more. Here, LHV (Lower Heating Value) is a lower heating value reference. The lower heating value standard (LHV) is a heating value obtained by subtracting the latent heat of condensation of water vapor when the fuel gas is completely burned. If the power generation efficiency of the generator 20 is less than 30% LHV, even if an inexpensive LPG is used, the ratio of the fuel cost to the power generation cost may increase. Therefore, the LPG in the LPG storage unit 10 should be used effectively. There is a risk that it will not be possible. The electric power generated by the generator 20 is supplied to the consumer's power receiving facility 60 through the electric power system 40.

  The electric power generated by the generator 20 may be supplied to electric equipment (not shown) in the LPG filling station 1. Thereby, the owner of the LPG filling station 1 can make the electrical equipment in the LPG filling station 1 completely operable at low cost even in an emergency, for example.

  The generator 20 has a connection portion 20a that connects the LPG to the distribution facility 30 so that the LPG can flow. The end portion of the connecting portion 20a is movable as indicated by the arrow in FIG. 1 and is configured to be detachable from the plurality of supply ports 31a and 31b of the distribution facility 30 similarly to the container 50. Since the container 50 and the connecting portion 20a are configured to be detachable from the plurality of supply ports 31a and 31b of the distribution facility 30, for example, the container 50 filled with LPG is removed from the supply port 31b and the connecting portion of the generator 20 is removed. 20a can be attached to the supply port 31b. Thereby, LPG used as fuel can be supplied to the generator 20 without adding a new configuration (equipment) to the existing LPG storage unit 10 and the distribution facility 30. The generator 20 may receive the LPG supply from the LPG storage unit 10 through a dedicated pipe without passing through the supply port 31b of the distribution facility 30.

  The distribution facility 30 has a valve (not shown) and can supply LPG to at least one of the plurality of supply ports 31a and 31b. Therefore, when the container 50 and the generator 20 are connected to the plurality of supply ports 31 a and 31 b, the distribution facility 30 can supply LPG to at least one of the container 50 and the generator 20.

The generator 20 can be constituted by, for example, a gas engine or a fuel cell that can generate electricity. For example, in a normal fuel cell, the first stage reaction waste (H ₂ or CO) is burned, and in addition to the first stage reaction heat, hot water is generated by the combustion heat. By using this normal fuel cell as the generator 20, the power generation efficiency can be set to 40 to 50% LHV.

In addition, the fuel recycling type fuel cell uses the second-stage fuel without burning the reaction product (H ₂ or CO) of the first-stage reaction. With such a two-stage configuration, the amount of combustion of H ₂ and CO can be reduced as compared with a normal fuel cell. In addition, the amount of power generation can be increased by reducing the amount of combustion of H ₂ and CO. In other words, the fuel-recycling fuel cell having such a two-stage configuration can suppress the amount of heat generated from the fuel-recycling fuel cell and increase the amount of power generation accordingly. Therefore, electricity can be generated more efficiently than a normal fuel cell. By using a fuel-recycling fuel cell as the generator 20, the power generation efficiency can be 60 to 65% LHV. Therefore, the fuel recycling type fuel cell having a two-stage configuration is suitable as a single power generation system.

In particular, among the fuel recycling type fuel cells, the fuel recycling type fuel cell (HESO: see Japanese Patent No. 6061969) separates H ₂ and CO from the first stage reaction emissions (H ₂ and CO). Therefore, the power generation efficiency can be made larger than 65% LHV. Here, the fuel recycling regenerative fuel cell means that H ₂ and CO are separated from H ₂ O and / or CO ₂ or both from (removed) H ₂ O and CO ₂ from the first stage reaction emission (anode off gas). It is a fuel recycling type fuel cell. Therefore, the fuel recycling regenerative fuel cell can generate electricity from the LPG of the LPG storage unit 10 with high efficiency. For this reason, it is preferable to apply a fuel recyclable fuel cell as the generator 20. In the first embodiment, an example in which a fuel recycling regenerative fuel cell is used as the generator 20 will be described.

  FIG. 2 is a schematic configuration diagram of the generator (fuel recycling regenerative fuel cell) 20. As shown in FIG. 2, the generator 20 includes a desulfurizer 21, a reformer 22, a first fuel cell 23, a removal unit 24, a second fuel cell 25, a combustion unit 26, and a heat exchanger. 27, a fuel supply path 28a, an oxygen supply path 28b, and an exhaust path 28c.

  The desulfurizer 21 removes the sulfur content in the LPG introduced into the fuel supply path 28a. The desulfurizer 21 is filled with, for example, activated carbon, silver zeolite, copper-zinc-based or nickel-zinc-based sorbent.

  The reformer 22 reforms the LPG desulfurized by the desulfurizer 21 into a reformed gas containing hydrogen. At this time, for example, water is introduced into the reformer 22 in addition to the desulfurized LPG.

  The first fuel cell 23 generates power using the reformed gas supplied from the reformer 22. The first fuel cell 23 includes an anode (fuel electrode) 23a, an electrolyte 23b, and a cathode (air electrode) 23c. The reformed gas is supplied to the anode 23a via a fuel supply path 28a, and the cathode 23c is supplied to the cathode 23c. A gas (for example, air) containing oxygen is supplied through the oxygen supply path 28b.

  In the case where the first fuel cell 23 is a solid oxide fuel cell (SOFC), a gas containing oxygen is supplied to the cathode 23c, so that oxygen receives electrons at the cathode 23c and becomes oxygen ions. Oxygen ions generated at the cathode 23c move inside the electrolyte 23b and reach the anode 23a. In addition, when the reformed gas containing hydrogen and CO is supplied to the anode 23a, the hydrogen and CO react with oxygen ions that have moved through the electrolyte 23b to generate electrons. The electrons generated at the anode 23a move to the cathode 23c through an external circuit. As described above, the electrons move from the anode 23 a to the cathode 23 c, thereby generating power in the first fuel cell 23.

The removal unit 24 is fed with anode off-gas containing unreacted reformed gas discharged from the anode 23 a of the first fuel cell 23. The removing unit 24 removes H ₂ O (water) and CO ₂ (carbon dioxide) from the introduced anode off gas. However, the removing unit 24 may remove at least one of water and carbon dioxide.

The second fuel cell 25 is provided downstream of the first fuel cell 23 (and the removal unit 24), and generates power using the anode off-gas from which H ₂ O and CO ₂ have been removed. The second fuel cell 25 includes an anode (fuel electrode) 25a, an electrolyte 25b, and a cathode (air electrode) 25c. An anode off gas from which H ₂ O and CO ₂ have been removed is supplied to the anode 25a through a fuel supply path 28a, and a gas (air) containing oxygen is supplied to the cathode 25c through an oxygen supply path 28b. Thereby, in the 2nd fuel cell 25, electric power generation is performed like the 1st fuel cell 23.

Thus, the second fuel cell 25 generates power using the anode off gas from which H ₂ O and CO ₂ have been removed. Therefore, in the second fuel cell 25, the theoretical voltage due to the oxygen partial pressure difference between the electrodes is improved, and the concentration overvoltage due to water vapor and carbon dioxide in the anode off-gas is reduced, and high performance is achieved particularly at high current density. It can be demonstrated. Therefore, the fuel recycle regenerative fuel cell 20 includes a normal fuel cell and a fuel recycle fuel cell that generates power using the anode off gas from which H ₂ O and CO ₂ have not been removed in the second fuel cell in the subsequent stage. Compared with, it is possible to obtain higher power generation efficiency.

  The combustion unit 26 introduces oxygen-containing gas (air) introduced from the cathode 25c of the second fuel cell 25 via the oxygen supply path 28b, and introduces the anode 25a of the second fuel cell 25 via the fuel supply path 28a. A mixed gas with the anode off gas is introduced. The combustion unit 26 burns the introduced mixed gas. Exhaust gas discharged from the combustion unit 26 is introduced into the reformer 22 via the exhaust path 28 c and heats the reforming catalyst in the reformer 22. Exhaust gas discharged from the combustion unit 26 and heating the reforming catalyst in the reformer 22 is discharged from an exhaust hole (not shown) through the exhaust path 28c.

  The heat exchanger 27 is provided on the exhaust passage 28c and the oxygen supply passage 28b downstream from the reformer 22, and heat is generated between the exhaust flowing through the exhaust passage 28c and the air flowing through the oxygen supply passage 28b. Exchange. As a result, the exhaust gas flowing through the exhaust passage 28c is cooled and then discharged from an exhaust hole (not shown), and the air flowing through the oxygen supply passage 28b is heated to a temperature suitable for the operating temperature of the first fuel cell 23. Is supplied to the cathode 23c of the first fuel cell 23.

  In the present embodiment, the exhaust gas discharged from the combustion unit 26 heats the reforming catalyst in the reformer 22 and the air flowing through the oxygen supply path 28b. However, the first fuel cell 23 and the second fuel are used. These may be heated using the heat released from the battery 25. Thereby, the combustion part 26 can also be abbreviate | omitted.

  The fuel recyclable fuel cell 20 is a two-stage fuel cell in which a first fuel cell (fuel cell stack) 23 and a second fuel cell (fuel cell stack) 25 are stacked and electrically connected in series. Also good. By electrically connecting in series, the voltage can be increased and the conversion efficiency of the power conditioner can be increased as compared with when electrically connecting in parallel. In addition, the number of DC / DC converters can be reduced to one instead of the number of fuel cell stacks, and the cost of the fuel recycling and regenerative fuel cell system can be reduced.

  When a fuel recycle regeneration type fuel cell is applied as the generator 20, the fuel recycle regeneration type fuel cell can generate power of 5 to 10 kW. Further, by connecting a plurality of such fuel recyclable regenerative fuel cells with a power generation amount of 5 to 10 kW in parallel, it is possible to generate a large capacity (for example, on the order of several tens to several hundred kilowatts). Therefore, the LPG filling station 1 that accumulates a large amount of LPG generates electric power by using the LPG and the generator 20, thereby obtaining the same amount of power generation as that of a large-capacity power station. As described above, there are 2200 LPG filling stations 1 nationwide, and since power can be generated at a plurality of locations, the power generation location and the demand location can be close to each other, and transmission loss (cost) can be reduced. Can do.

  In addition, as described above, the generator 20 includes the plurality of supply ports 31a and 31b of the distribution facility 30 and the connecting portion 20a that can be attached and detached. Therefore, LPG as fuel can be supplied to the generator 20 without adding a new configuration to the existing LPG storage unit 10 and the distribution facility 30. In this embodiment, since the LPG can be supplied to the generator 20 by using the existing LPG storage unit 10 and the distribution facility 30 in this way to generate electric power, the owner who owns the LPG filling station 1 A power generation system can be constructed at a low cost.

  In addition, the distribution facility 30 can simultaneously supply the LPG to the container 50 and supply the LPG to the generator 20. Therefore, it is possible to generate power with the generator 20 while maintaining the supply of LPG to the container 50.

  In addition, since the generator 20 is connected to the consumer's power receiving facility 60 via the power system 40 (see FIG. 1), the consumer who owns the power receiving facility 60 does not introduce a household fuel cell. And the electric power produced | generated from LPG can be obtained cheaply, without purchasing an LPG cylinder from a sales office. Furthermore, when the generator 20 generates power, an inexpensive LPG that is directly supplied from the LPG storage unit 10 (that is, not via the sales office) is used, and therefore, an LPG cylinder purchased from the sales office is used. Electric power can be supplied at a lower cost than when electric power is generated. In other words, it is possible to supply power generated at low cost using inexpensive fuel. In addition, since a large amount of power can be supplied at a low cost, it is possible to sell power in a reverse tide.

  Thus, according to the LPG filling station 1 of this embodiment, electric power can be supplied at low cost.

(Second Embodiment)
FIG. 3 is a schematic diagram of the LPG stand 2 in the second embodiment. Among the constituent elements of the present embodiment, the same constituent elements as those of the first embodiment are denoted by the same reference numerals as those of the first embodiment, and description thereof is omitted.

  The LPG stand is a base having a distribution facility for distributing LPG from an LPG storage unit to a predetermined container. In this embodiment, the LPG stand (LPG supply facility) 2 includes an LPG storage unit 110 that stores LPG, and a distribution facility that distributes the LPG of the LPG storage unit 110 to a predetermined container (a fuel tank of the LPG vehicle 150) 150a. LPG distributor 130). The LPG stand 2 is installed, for example, at 1500 locations throughout the country. The LPG vehicle 150 is an automobile that runs using LPG as fuel.

  The distribution facility 130 is connected to the LPG storage unit 110 and includes a pipe 131, a dispenser 132, and a nozzle 133. The pipe 131 connects the LPG storage unit 110 and the dispenser 132 and transfers the LPG delivered from the LPG storage unit 110 to the dispenser 132. The dispenser 132 controls supply of LPG to the container 150a and supply stop. The nozzle 133 connects the dispenser 132 and the container 150a which is a fuel tank of the LPG vehicle 150, and distributes LPG delivered from the dispenser 132 to the container 150a. As described above, the distribution facility 130 distributes the LPG from the LPG storage unit 110 to the container 150 a that is a fuel tank of the LPG vehicle 150.

  In addition, the distribution facility 130 includes a plurality of supply ports 133 a and 133 b provided at the tips of the plurality of nozzles 133. The plurality of supply ports 133a and 133b are configured to be detachable from the respective containers 150a. When the container 150a is attached to each of the plurality of supply ports 133a and 133b, the distribution facility 130 can simultaneously distribute (fill) the LPG in the LPG storage unit 110 to the plurality of containers 150a. The LPG filled in the container 150a is consumed as fuel when the LPG vehicle 150 travels.

  The LPG stand 2 in this embodiment includes a generator 20 that generates electricity using the LPG in the LPG storage unit 110 as fuel. In this way, by installing the generator 20 in the LPG stand 2 so that electric power can be generated, the LPG remaining in the LPG storage unit 110 can be effectively utilized. The generator 20 is a generator having a power generation efficiency of 30% LHV or more, as in the first embodiment.

  The generator 20 has a connection portion 120a that connects the LPG to the distribution facility 130 so that the LPG can flow. The end portion of the connecting portion 120a is movable as shown by the arrow in FIG. 3, and is configured to be detachable from the plurality of supply ports 133a and 133b of the distribution facility 130, similarly to the container 150a. Since the container 150a and the connecting portion 120a are configured to be detachable from the plurality of supply ports 133a and 133b of the distribution facility 130, for example, the supply port 133b (nozzle 133) is removed from the container 150a filled with LPG, and the generator Twenty connecting portions 120a can be attached to the supply port 133b (nozzle 133). Thereby, LPG used as fuel can be supplied to the generator 20 without adding a new configuration (equipment) to the existing LPG storage unit 110 and the distribution facility 130. The generator 20 may receive the LPG from the LPG storage unit 110 through a dedicated pipe without passing through the supply ports 133a and 133b of the distribution facility 130.

  With such a configuration, the LPG stand 2 of the present embodiment can obtain the same effects as those of the first embodiment described above.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  In the above embodiment, an example in which electric power is generated by a fuel recyclable fuel cell has been described. However, the present invention is not limited to this, and for example, a gas engine generator that generates electric power by driving a generator with a gas engine. The electric power may be generated by the above. By using a gas engine generator as the generator 20, the power generation efficiency can be 30% LHV or more. Specifically, when a micro gas turbine having a power generation amount of about several tens of kW is used as the power generator 20, the power generation efficiency can be set to 30 to 34% LHV.

  The present invention can be used in a power generation system that generates power using LPG as fuel.

1 LPG filling station (LPG supply facility)
10, 110 LPG storage unit 20 Generator 30, 130 Distribution facility (LPG distribution unit)

Claims (5)

An LPG supply facility comprising an LPG storage unit for storing LPG, and an LPG distribution unit for distributing the LPG of the LPG storage unit to a predetermined container;
A generator that is provided in the LPG supply facility, uses the LPG in the LPG storage unit as fuel, and generates electricity with a power generation efficiency of 30% LHV or more;
A power generation system comprising:   The power generation system according to claim 1, wherein the generator is a fuel cell.   The power generation system according to claim 1, wherein the generator is a fuel recycling type fuel cell.   The power generation system according to claim 1, wherein the generator is a fuel recycling regenerative fuel cell.   The power generation system according to claim 1, wherein the generator is a gas engine.

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