JP2006196249A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system enhancing energy efficiency of the whole system, allowing the system compact, stabilizing operation, and reducing cost. <P>SOLUTION: A first humidifier is constituted by stacking a plurality of first passage plates each forming a passage of at least one supply gas of supply fuel gas and supply oxidant gas and a plurality of second passage plates each forming a passage of at least one of exhausting fuel gas and exhausting oxidant gas so that the supply gas passage comes in contact with the exhausting gas passage through a moisture moving membrane, a second humidifier is constituted by stacking a plurality of second passage plates each forming a passage of at least one supply gas of supply fuel gas and supply oxidant gas and a plurality of first passage plates forming a passage of cooling water so that the supply gas passage comes in contact with the cooling water passage through the moisture moving membrane, the exhaust gas passage inlet of the first humidifier is arranged in the upper part than the exhaust gas passage outlet, and the cooling water passage inlet of the second humidifier is arranged in the lower part than the cooling water passage outlet. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel cell system that uses a fuel cell to generate power and supply heat.

  Conventionally, in this type of fuel cell system, in a fuel cell, electric power and heat are generated by reacting a hydrogen-rich gas supplied as a fuel gas with air supplied as an oxidant gas. Are known. The fuel gas and the oxidant gas are supplied to the fuel cell after being humidified by the humidifying means. As a means for humidifying the fuel gas and the oxidant gas, for example, there is a bubbler that performs humidification through the fuel gas and the oxidant gas in warm water heated by a heater (see, for example, Patent Document 1).

On the other hand, moisture (water vapor) contained in the exhaust air (off gas) discharged from the air electrode side of the fuel cell is moved to the air supplied to the air electrode side of the fuel cell through the water vapor permeable membrane and supplied thereby Humidifying devices that humidify air are also known (see, for example, Patent Document 2). This humidifier can reduce energy required for humidification by performing humidification using high-temperature exhaust air.
JP 7-288134 A JP-A-6-132038

  However, in the above-described conventional configuration, the bubbler consumes energy to heat the water, leading to a decrease in energy efficiency of the fuel cell system.

  In addition, when humidifying with off-gas, the humidified gas (here, the supply air to be humidified) cannot be humidified to a dew point temperature higher than the humidified gas (here, the exhaust air from which moisture is supplied), Furthermore, in order to humidify the humidified gas to a high dew point temperature, a water vapor permeable membrane having a large membrane area is required, and there is a problem that the scale of the humidifying device becomes large.

  Therefore, it is difficult to make the conventional fuel cell system compact.

  In order to solve the above-described conventional problems, the present invention performs humidification using moisture contained in at least one of exhaust gas and exhaust gas such as fuel gas and oxidant gas discharged from a fuel cell. In the fuel cell system, the first humidifier includes a first flow path plate that forms a flow path of at least one of the supply fuel gas and the supply oxidant gas, the exhaust fuel gas, and the A plurality of second flow path plates forming a flow path for at least one of the exhaust oxidant gases are stacked so that the flow path for the supply gas and the flow path for the exhaust gas are in contact with each other through a moisture transfer film. Further, at least one exhaust gas passage inlet of the exhaust fuel gas and the exhaust oxidant gas of the first humidifier is disposed above the exhaust gas passage outlet. Accordingly, the water contained in at least one of the fuel gas discharged from the fuel cell and the oxidant gas, which is the exhaust fuel gas and the exhaust oxidant gas, is retained when condensed in the first humidifier. It is possible to prevent the air supply device from increasing in size due to an increase in pressure loss.

  In the fuel cell system, a second humidifying device for humidifying at least one of a supply fuel gas and a supply oxidant gas such as a fuel gas and an oxidant gas supplied to the fuel cell is provided with warm water as cooling water. And the second humidifier is further provided with a second flow path plate that forms a flow path for at least one of the supply fuel gas and the supply oxidant gas, and cooling water. A plurality of first flow path plates that form flow paths are stacked so that the flow path of the supply gas and the flow path of the cooling water are in contact with each other via the moisture transfer film. The cooling water flow channel inlet is disposed below the cooling water flow channel outlet, and the cooling water flows through the first flow in the cooling water flow channel during operation in the second humidifier. Full inside the road plate In a state, as a result, decrease in the transfer efficiency of the temperature and humidity due to biting of the air in the flow path can be prevented.

  In addition to reducing the energy required for humidifying the gas supplied to the fuel cell, the fuel cell system of the present invention improves the efficiency of temperature / humidity exchange in the humidifier, thereby further improving the energy efficiency of the entire system. The system can be made more compact, the system operation can be stabilized, and the cost can be reduced.

  The invention according to claim 1 is a fuel cell that generates power using a fuel gas and an oxidant gas, and a fuel gas and a oxidant that are supplied to the fuel cell, such as a fuel gas and an oxidant gas, respectively. A first humidifying device for humidifying at least one of the gases, wherein the first humidifying device is an exhaust fuel gas and an exhaust oxidant gas that are the fuel gas and the oxidant gas respectively discharged from the fuel cell; In the fuel cell system in which humidification is performed using moisture contained in at least one of the above, the first humidifier is provided with a flow path for at least one of the supply fuel gas and the supply oxidant gas. A first flow path plate to be formed and a second flow path plate that forms a flow path for at least one of the exhaust fuel gas and the exhaust oxidant gas are disposed through a moisture transfer film. And the exhaust gas flow of at least one of the exhaust fuel gas and the exhaust oxidant gas of the first humidifier is further laminated. The passage inlet is disposed above the exhaust gas passage outlet.

  With this configuration, moisture contained in at least one of the fuel gas discharged from the fuel cell and the exhaust fuel gas that is the oxidant gas and the exhaust oxidant gas is condensed in the first humidifier. It flows out without staying at the time, and an increase in the size of the air supply device accompanying an increase in pressure loss can be prevented. As a result, an increase in the size of the air supply device accompanying an increase in pressure loss can be prevented, system operation can be stabilized, and a low-cost, compact fuel cell cogeneration system can be provided.

  According to a second aspect of the present invention, there is provided a fuel cell that generates power using a fuel gas and an oxidant gas, a supply fuel gas such as a fuel gas and an oxidant gas supplied to the fuel cell, and a supply oxidant. A fuel cell system comprising a second humidifier that humidifies at least one of gases, wherein the second humidifier is humidified using warm water that is cooling water. A second flow path plate that forms a flow path of at least one of the supply fuel gas and the supply oxidant gas, and a first flow path plate that forms a flow path of cooling water. A plurality of the supply gas flow path and the cooling water flow path are stacked so that the cooling water flow path is in contact with the cooling water flow path outlet in the second humidifier. It is arranged below.

  With this configuration, during operation, the cooling water in the second humidifier can be filled in the first flow path plate in the cooling water flow path, and the air in the flow path It is possible to prevent the temperature / humidity exchange efficiency from being lowered due to the biting of. As a result, a stable system operation can be obtained, and a low-cost, compact, and highly efficient fuel cell cogeneration system can be provided.

  According to a third aspect of the present invention, there is provided a fuel cell that generates power using a fuel gas and an oxidant gas, a supply fuel gas such as a fuel gas and an oxidant gas supplied to the fuel cell, and a supply oxidant. A humidifier that humidifies at least one of the gases, the humidifier including a first humidifier sandwiched between a first end plate and a second end plate, the second end plate, and a third The second humidifier is sandwiched between end plates, and the first humidifier is configured to supply exhaust fuel gas and exhaust oxidant gas such as the fuel gas and oxidant gas discharged from the fuel cell, respectively. In the fuel cell system, wherein the humidification is performed using moisture contained in at least one of the two humidification devices, and the humidification is performed using warm water that is cooling water. The apparatus comprises the supply fuel gas and A first flow path plate that forms a flow path for at least one of the supply oxidant gases; and a second flow path that forms a flow path for at least one of the exhaust fuel gas and the exhaust oxidant gas. A plurality of flow path plates are laminated so that the flow path of the supply gas and the flow path of the exhaust gas are in contact with each other through a moisture transfer film, and the second humidifier is further provided with the supply fuel gas And the second flow path plate that forms a flow path of at least one of the supply oxidant gas and the first flow path plate that forms the flow path of the cooling water, A plurality of stacked gas gas flow paths and the cooling water flow path are in contact with each other, and at least one of the exhaust fuel gas and the exhaust oxidant gas in the first humidifier Discharge the channel inlet Than scan flow path outlet is obtained by arranged above.

  By setting it as this structure, the remarkable fall of the water temperature in a said 2nd humidification apparatus can be suppressed, and the energy consumed for maintenance of the said water temperature can be suppressed. In addition, retention in the first humidifier due to condensation of moisture contained in at least one of the exhaust gas and the exhaust oxidant gas that is the fuel gas and the oxidant gas discharged from the fuel cell is suppressed. Thus, it is possible to prevent an increase in the size of the air supply device accompanying an increase in pressure loss due to this. As a result, an increase in the size of the air supply device accompanying an increase in pressure loss can be prevented, system operation can be stabilized, and a low-cost, compact fuel cell cogeneration system can be provided.

  Invention of Claim 4 arrange | positions the cooling water flow path inlet in the said 2nd humidification apparatus below a cooling water flow path exit, The cooling water in the said 2nd humidification apparatus at the time of driving | operation is When the first flow path plate in the cooling water flow path is full, it is possible to prevent a decrease in temperature / humidity exchange efficiency due to air entrapment in the flow path, and a stable system operation is obtained. A low-cost, compact and highly efficient fuel cell cogeneration system can be provided.

(Embodiment 1)
FIG. 1 is a schematic diagram showing a configuration of a fuel cell cogeneration system (hereinafter simply referred to as a fuel cell system) according to Embodiment 1 of the present invention.

  As shown in FIG. 1, the fuel cell system of the present embodiment includes an air supply device 40, a first humidifying device 22, a humidifying device 50 including a second humidifying device 21a, a fuel cell 11, and a fuel. Supply device 41, fuel processing device 42, fuel processing humidifier 21b, cooling water radiator 13, cooling water tank 14, cooling water pump 12, air path 3, and first cooling water flow path 6a The second cooling water flow path 6b, the third cooling water flow path 6c, the hot water storage tank 45, and the hot water storage water circulation path 15 are included as main elements.

  The air supplied from the air supply device 40 to the humidifier 50 via the air path 1 is humidified by the first humidifier 22 and further humidified by the second humidifier 21a. The air humidified by the second humidifier 21a is supplied to the air electrode side of the fuel cell 11 through the air path 3 as an oxidant gas.

  On the other hand, the fuel processing device 42 is supplied from the fuel supply device 41 via the fuel path 8 with a gas containing at least a compound composed of carbon and hydrogen, and a raw material such as alcohol. As the gas containing the compound composed of carbon and hydrogen and the alcohol, for example, city gas, propane, methane, natural gas and the like are preferable. Here, as the fuel processing device 42, specifically, a reforming unit that generates a reformed gas containing hydrogen by a reforming reaction, and a shift unit that reduces carbon monoxide in the reformed gas by a shift reaction, The case where the structure provided with the purification | cleaning part which further reduces carbon monoxide in the reformed gas which passed through this metamorphic part by selective oxidation reaction is demonstrated.

  In the fuel processing device 42, a hydrogen-rich gas is generated by heating the supplied raw material in an atmosphere containing water vapor. The hydrogen-rich gas is supplied to the fuel processing humidifier 21b via the fuel gas path 9a and humidified. Here, as the fuel processing humidifier 21b, the humidifier described above in the second humidifier 21a is used.

  The humidified hydrogen-rich gas is supplied as a fuel gas of the fuel cell 11 to the fuel electrode side of the fuel cell 11 through the fuel gas path 9b. In the fuel cell 11, electricity is generated by the reaction between the air supplied to the air electrode side and the hydrogen-rich gas (hereinafter referred to as fuel gas) supplied to the fuel electrode side, generating electricity and heat. To do.

  Of the air supplied to the fuel cell 11, the air that has not been used for the reaction is supplied to the first humidifier 22 via the exhaust air path 4. In the first humidifier, the moisture supplied to the fuel cell 11 as an oxidant gas is humidified using moisture contained in the supplied exhaust air. And the air which passed through the 1st humidification apparatus 22 is discharged | emitted through the exhaust gas path | route 5 arrange | positioned below the exhaust air path | route 4. FIG. On the other hand, the fuel gas that has not been used for the reaction in the fuel cell 11 is discharged through the exhaust gas path 10.

  The second cooling device 21a is connected to the first cooling water flow path 6a recovered from the fuel cell 11, passes through the air path 1, and the air humidified by the first humidifying device 22 is supplied to the second humidifying device 21a. The cooling water further humidified in (5) flows into the second cooling water flow path 6b disposed above the first cooling water flow path 6a.

  The hot water storage tank 45 and the hot water storage pump 44 for supplying the water stored in the hot water storage tank 45 and the water supplied from the hot water storage tank 45 are returned to the hot water storage tank via the cooling water radiator 13 constituted by a heat exchanger. Heat is supplied to the cooling water radiator 13 from the cooling water that has been used for humidification by the second humidifier 21 a by the hot water circulating path 15 that returns to 45, and this heat passes through the hot water circulating path 15 to store hot water. It is supplied to the water tank 45 and stored here.

  Further, in order to remove the heat generated in the fuel cell 11, the cooling water in the cooling water tank 14 is pressurized by the cooling water pump 12 and supplied to the fuel cell 11 through the cooling water channel 7. Here, the cooling water in the cooling water tank 14 is maintained at about 70 ° C. The heat of the fuel cell 11 is removed by the supplied cooling water.

  Then, the cooling water whose temperature has been recovered by recovering the heat passes through the first cooling water flow path 6a, the second cooling water flow path 6b, and the third cooling water flow path 6c in order, and again becomes the cooling water. Returned to tank 14. Here, a cooling water radiator 13 is provided between the second cooling water channel 6 b and the third cooling water channel 6 c, and heat of the cooling water is released by the cooling water radiator 13. By such heat radiation, the cooling water is cooled again to about 70 ° C.

  In the fuel cell system, the cooling water is circulated in this way, and the temperature of the cooling water is stably maintained at a predetermined temperature, so that the fuel cell 11 is maintained at a predetermined temperature. It becomes possible to do.

  Next, the humidifier 50 that is a feature of the present embodiment will be described.

  2, 3, 4, and 5 are diagrams for explaining the configuration of the first humidifier in the fuel cell system of FIG. 1, and FIG. 2 schematically illustrates the configuration of the first flow path plate. FIG. 3 is a perspective view schematically showing the configuration of the second flow path plate, and FIG. 4 is a diagram in which the first flow path plate of FIG. 2 and the second flow path plate of FIG. FIG. 5 is a schematic longitudinal sectional view showing the configuration of the humidifying device of FIG. 4.

  As shown in FIGS. 4 and 5, the first humidifier 22 is inserted between the first end plate 31 and the second end plate 32, and the first flow path plate 24 and the second end plate 32 are connected to each other. Two flow path plates 25 are alternately stacked via a moisture transfer film 23. The exhaust gas passage inlet 51 is disposed on the first end plate 31 so as to be positioned above the exhaust gas passage outlet 52.

  Here, the moisture transfer membrane 23 is a membrane that selectively permeates moisture, and for example, a proton conductive polymer electrolyte membrane such as a Nafion-based membrane is used.

  Next, the first humidifying device 21 including the first flow path plate 24 and the second flow path plate 25 will be described with reference to FIGS.

  The first flow path plate 24 and the second flow path plate 25 are made of a rectangular metal material as shown in the figure, and have outer peripheral seal portions 24s and 25s along the outer periphery, respectively. The outer peripheral seal portions 24s and 25s seal leakage of supply air and discharge air from the first humidifier 22 to the outside in the stacked state of the first flow path plate 24 and the second flow path plate 25. It is.

  The first flow path plate 24 is provided with a flow path (hereinafter referred to as a supply flow path) 24a for air supplied from the air supply device 40 at the center as shown in FIG. The supply flow path 24 a is formed by a hollow portion (through space) through which the first flow path plate 24 penetrates. In addition, a pair of manifold holes 28a and 28b communicating with the supply flow path 24a are provided at different positions (diagonal positions in FIG. 2).

  Similarly, the second flow path plate 25 is provided with a flow path (hereinafter referred to as a discharge flow path) 25a for air discharged from the fuel cell 11 at the center as shown in FIG. The discharge channel 25 a is formed by a hollow portion (through space) through which the second channel plate 25 penetrates. In addition, a pair of manifold holes 29a and 29b communicating with the discharge flow path 25a are provided at different positions (diagonal positions in FIG. 3).

  Further, the first flow path plate 24 has manifold holes 29a and 29b communicating with the respective manifold holes 29a and 29b provided in the second flow path plate 25 in a stacked state with the second flow path plate 25. The holes 28a and 28b are provided at different positions (different diagonal positions). Although not shown, a sealing material is provided around each of the manifold holes 29a and 29b provided in the first flow path plate 24.

  Similarly, for the second flow path plate 25, manifold holes 28 a and 28 b communicating with the manifold holes 28 a and 28 b provided in the first flow path plate 24 in a stacked state with the first flow path plate 24. Are provided at different positions (different diagonal positions) from the manifold holes 29a and 29b. Although not shown, a sealing material is provided around each of the manifold holes 28a and 28b provided in the second flow path plate 25.

  Therefore, in the mutually laminated state of the first flow path plate 24 and the second flow path plate 25, four passages in which the manifold holes 28a, 28b, 29a, 29b communicate with each other are configured. This passage will be described later.

  The first flow path plate 24 and the second flow path plate 25 having the above-mentioned configuration are alternately stacked as appropriate through the moisture transfer film 23 and sandwiched between the first end plate 31 and the second end plate 32. By doing so, the 1st humidification apparatus 22 is comprised.

  As a result, the manifold hole 28a forms a supply air introduction flow path 28a 'extending in the stacking direction while communicating with the supply flow path 24a closed on both sides by the moisture transfer film 23. Similarly, the manifold hole 28b A supply air take-out flow path 28b ′ extending in the stacking direction is formed in communication with the supply flow path 24a whose both surfaces are closed by the transfer film 23, and the manifold hole 29a is a discharge flow whose both faces are closed by the moisture transfer film 23. An exhaust air introduction passage 29a ′ extending in the stacking direction while communicating with the passage 25a is formed. Similarly, the manifold hole 29b communicates with the discharge passage 25a whose both surfaces are closed by the moisture transfer film 23 in the stacking direction. An extended exhaust air extraction passage 29b 'is formed.

  The inlet end of the supply air introduction flow path 28a ′ formed by communication with the manifold hole 28a is connected to the air path 1 via the first end plate 31, and the supply air formed by communication with the manifold hole 28b. The take-out flow path 28 b ′ is connected to a manifold hole 30 provided in the second end plate 32. The inlet end of the exhaust air introduction flow path 29a ′ is connected to the inflow side exhaust air path 4 via the first end plate 31, and the exhaust air introduction flow path 29a ′ via the discharge flow path 25a. The outlet end of the exhaust air extraction passage 29 b ′ communicated with the exhaust air is communicated with the exhaust air passage 5 on the outflow side via the first end plate 31.

  Here, as described above, in the first end plate 31, the exhaust gas passage outlet 52 corresponding to the exhaust air passage 5 is positioned below the exhaust gas passage inlet 51 corresponding to the exhaust air passage 4. The arrangement is configured.

  The 1st humidification apparatus 22 is comprised by the above structure.

  Next, the second humidifier 21a will be described.

  As shown in FIGS. 4 and 5, the second humidifier 21 a is interposed between the second end plate 32 and the third end plate 33. Similarly to the first humidifier 22, the second humidifier 21 a is connected to the first flow path plate 24 and the second flow path plate 25 shown in FIGS. 2 and 3 through the moisture transfer film 23. In this structure, the air and cooling water are not leaked to the outside.

  Therefore, the manifold hole 28a forms a cooling water introduction flow path 6a ′ extending in the stacking direction while communicating with the supply flow path 24a whose both surfaces are closed by the moisture movement film 23. Similarly, the manifold hole 28b A cooling water take-out flow path 6b ′ extending in the stacking direction is formed in communication with the supply flow path 24a closed on both sides by the membrane 23, and the manifold hole 29a is a discharge flow path closed on both sides by the moisture transfer film 23. A supply air introduction channel 29a '' extending in the stacking direction while communicating with 25a is formed. Similarly, the manifold hole 29b communicates with the discharge channel 25a closed on both sides by the moisture transfer film 23 in the stacking direction. An extended supply air outlet passage 29b '' is formed.

  Then, the inlet end of the cooling water introduction flow path 6a ′ formed by communicating the manifold hole 28a is connected to the first cooling water flow path 6a via the third end plate 33, and the manifold hole 28b is communicated. The cooling water take-out flow path 6 b ′ is connected to the second cooling water flow path 6 b provided in the third end plate 33.

  The inlet end of the supply air introduction flow path 29a ″ is connected to the manifold hole 30 provided in the second end plate 32, and is connected to the supply air introduction flow path 29a ″ via the discharge flow path 25a. The outlet end of the supply air take-out flow path 29 b ″ communicated with the air path 3 through the third end plate 33.

  Here, in the third end plate 33, the cooling water flow path inlet 53 corresponding to the first cooling water flow path 6a is positioned below the cooling water flow path outlet 54 corresponding to the second cooling water flow path 6b. The arrangement is configured.

  By sandwiching the laminated structure of the first plate 24 and the second plate 25 with the second end plate 32 and the third end plate 33 in a state in which the respective paths are formed, the second humidifier 21a. Is configured.

  As a result, as shown in FIG. 4 and FIG. 5, a humidifier 50 incorporating the first humidifier 22 and the second humidifier 21a is configured.

  Next, the operation and action of the fuel cell system configured as described above will be described.

  First, in the first humidifier 22, the air (supply air) supplied from the air path 1 flows through the supply air introduction flow path 28 a ′ communicated with the manifold hole 28 a and passes through the first humidifier 22. Is supplied to the flow path plate 24, flows into the supply path 24 a, flows through the supply air take-out flow path 28 b ′ from here, and is supplied to the manifold hole 30 of the second end plate 32.

  On the other hand, an exhaust air introduction flow path 29a ′ in which the manifold hole 29a communicates is connected to the air path 4, and an exhaust air extraction flow path 29b ′ in which the manifold hole 29b communicates with the air path 5 It is connected to the.

  Therefore, the air (exhaust air) supplied from the air path 4 to the second flow path plate 25 constituting the first humidifier 22 flows through the exhaust air introduction flow path 29a ', but the second end plate 32, the linear flow is blocked, and as a result, it flows along the discharge flow path 25a of the second plate 25, and flows through the discharge flow path 29b 'of the discharge air, thereby forming a substantially U-shaped flow path. And flows to the air path 5.

  Here, in the discharge flow path 25a of the second flow path plate 25, a flow of supply air and discharge air facing each other is formed. As a result, the water condensed in the air paths 4 and 5 and the second flow path plate 25 is pumped downward from above by the air supply device 40 and flows out of the first humidifying device 22.

  Since the plurality of first flow path plates 24 and second flow path plates 25 having the above-described configuration are laminated via the moisture transfer film 23, the first flow path plate 24 has a supply flow path 24a. The supply air flowing through the formed supply air flow path and the exhaust air flowing through the discharge air flow path formed in the discharge flow path 25 a of the second flow path plate 25 are in contact with each other through the moisture transfer film 23.

  Here, since the exhaust air discharged from the fuel cell 11 contains more moisture than the supply air, in the first humidifier 22 having such a configuration, the supply air is supplied from the exhaust air via the moisture transfer film 23. Moisture (specifically, water vapor) is given to. In particular, since the supply air and the discharge air are in contact with each other while forming an opposing flow as described above, the movement of the moisture is performed efficiently. Further, since the temperature of the exhaust air discharged from the fuel cell 11 is higher than that of the supply air, in the first humidifier 22, thermal energy is given from the exhaust air to the supply air as the moisture moves, thereby Supply air is heated.

  Next, in the second humidifying device 21a, the air is supplied from the manifold hole 30 of the second end plate 32 through the supply air introduction flow passage 29a '' to the second flow passage plate 25 in the second humidifying device 21a. The supplied air (supply air) flows along the discharge flow path 25a of the second flow path plate 25, and is sent to the air path 3 through the supply air take-out flow path 29b ''.

  On the other hand, the introduction flow path 6a ′ at the inlet of the cooling water flow path formed by communicating the manifold hole 28a is connected to the first cooling water flow path 6a, and the cooling water extraction flow path 6b formed by communicating the manifold hole 28b. 'Is connected to the second cooling water flow path 6b.

  A plurality of first flow path plates 24 and second flow path plates 25 having the above-described configuration are stacked via a moisture transfer film 23, respectively, and are supplied to the supply flow path 24a of the first flow path plate 24. The supply air flowing through the formed supply air flow path and the exhaust air flowing through the discharge air flow path formed in the discharge flow path 25 a of the second flow path plate 25 are in contact with each other through the moisture transfer film 23.

  Here, since the exhaust air discharged from the fuel cell 11 contains more moisture than the supply air, in the first humidifier 22 having such a configuration, the supply air is supplied from the exhaust air via the moisture transfer film 23. Moisture (specifically, water vapor) is given to. In particular, since the supply air and the discharge air are in contact with each other while forming an opposing flow, the movement of the moisture is performed efficiently. Further, since the temperature of the exhaust air discharged from the fuel cell 11 is higher than that of the supply air, in the first humidifier 22, thermal energy is given from the exhaust air to the supply air as the moisture moves, thereby Supply air is heated. At this time, the cooling water supplied from the first cooling water flow path 6a to the first flow path plate 24 in the second humidifying device 21a flows through the cooling water introduction flow path 6a ′, but the second end plate Since the linear flow is blocked by 32, it flows along the supply flow path 24a of the first plate 24 and flows through the cooling water take-out flow path 6b 'to form a substantially U-shaped flow path. It flows to the second cooling water channel 6b.

  Here, in the supply flow path 24a of the first flow path plate 24, opposed supply air and cooling water flow are formed, and between the cooling water flow path inlet 53 and the cooling water flow path outlet 54 are always in operation. The cooling water flows from the lower side to the upper side. As a result, the supply flow path 24a of the first flow path plate 24 is kept full. Therefore, the temperature and humidity exchange of the supply air and the cooling water is performed using the entire surface of the first flow path plate 24, and the exchange efficiency becomes higher.

  In addition, since the air supplied to the second humidifier 21a is heated and humidified in advance by the first humidifier 22 as described above, it is humidified only by the second humidifier 21a as in the past. Compared to the case, the second humidifier 21a may require less heating and humidification. Therefore, it is possible to reduce the heat energy and moisture required for the second humidifier 21a.

  As described above, in the present embodiment, since the supply air is heated and humidified in advance by the first humidifier 22, the energy consumed by the second humidifier 21 a is reduced, so that the energy of the entire system is reduced. Efficiency can be improved. Moreover, since the water consumption in the 2nd humidification apparatus 21a can be reduced, it becomes possible to suppress the quantity of the water | moisture content supplied to the 2nd humidification apparatus 21a. As a result, temperature fluctuation due to the replenished water can be suppressed, and a stable humidification amount can be realized in the second humidifier 21a.

  Furthermore, in the fuel cell system having such a configuration, the first humidifier 22 and the second humidifier 21a efficiently perform the humidification step by step. Therefore, even when the supply air is humidified to a high dew point, a large-scale is required. The first humidifier and the second humidifier are not required, and thus the system can be made compact.

  In the present embodiment, the case where the fuel gas supplied to the fuel cell 11 (hereinafter referred to as supply fuel gas) is humidified only by the fuel humidifier 21b has been described. As in the case of supply air, the first fuel humidifier can be provided upstream of the second fuel humidifier to humidify in stages.

  In such a configuration, the exhaust fuel gas discharged from the fuel cell 11 is supplied to the first fuel humidifier, and in the first fuel humidifier, the moisture of the exhaust fuel gas is given to the supply fuel gas, and the supply fuel gas While the humidification is performed, the heat energy of the exhaust fuel gas is given to the supply fuel gas to heat the supply fuel gas.

  As a result, as in the case of supply air, the energy consumption of the second fuel humidifier 21b can be reduced, the energy efficiency of the fuel cell system can be improved, and the water consumption in the second fuel humidifier 21b can be improved. The amount can be reduced, and the humidification amount can be stabilized. Such a first fuel humidifier is, for example, the same as the configuration of the first humidifier 22 described above on the air supply side, and the plurality of first flow path plates 24 and the second flow through the moisture transfer film 23. In this case, the supply flow path 24a of the first flow path plate 24 is a flow path through which the supply fuel gas flows, and the discharge flow path 25a of the second flow path plate 25 is provided. Is a flow path through which the exhaust fuel gas flows.

  Thus, in the fuel cell system, the first humidifier 22 that humidifies the supply gas using the exhaust gas from the fuel cell 11 may be provided on both the air side and the fuel side. It may be used for either. The exhaust air from the fuel cell 11 has a higher humidity than the exhaust fuel gas, and the exhaust air is more efficient than the exhaust fuel gas in transferring moisture through the moisture transfer film 23. Can be provided to the supply air. For this reason, it is preferable to arrange the first humidifier 22 on the air supply side.

  As described above, the fuel cell system according to the present invention reduces the energy required for humidifying the gas supplied to the fuel cell, thereby improving the energy efficiency of the entire system, making the system more compact and stabilizing the system operation. Therefore, it can be applied to uses such as dehumidification of air by utilizing the fact that the exhaust air path 4 of the first humidifier can be dehumidified.

Schematic diagram showing the configuration of the fuel cell system according to Embodiment 1 of the present invention. The perspective view which shows typically the structure of the 1st flow-path plate which comprises the humidification apparatus in the embodiment. The perspective view which shows typically the structure of the 2nd flow-path plate which comprises the humidification apparatus in the embodiment. Schematic perspective view of the humidifier in the same embodiment Schematic longitudinal cross-sectional view which shows the structure of the humidification apparatus of FIG. 4 in the embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,3,4 Air path 5 Exhaust air path 6a 1st cooling water flow path 6b 2nd cooling water flow path 6c 3rd cooling water flow path 7 Cooling water flow path 11 Fuel cell 12 Cooling water pump 13 Cooling water radiator 14 Cooling Water tank 15 Hot water storage path 21a Second humidifier 22 First humidifier 23 Moisture transfer film 24 First flow path plate 24a Supply flow path 24s, 25s Outer seal part 25 Second flow path plate 25a Discharge flow path 31 1st end plate 32 2nd end plate 33 3rd end plate 50 Humidifier 51 Exhaust gas channel inlet 52 Exhaust gas channel outlet 53 Cooling water channel inlet 54 Cooling water channel outlet

Claims (4)

  A fuel cell that generates power using a fuel gas and an oxidant gas; a fuel gas that is supplied to the fuel cell; a fuel gas such as an oxidant gas; and a oxidant gas that humidifies at least one of the supplied oxidant gas 1 is provided, and the first humidifier is configured to supply moisture contained in at least one of the fuel gas discharged from the fuel cell and the exhaust fuel gas and the exhaust oxidant gas which are the oxidant gas, respectively. In the fuel cell system that is used for humidification, the first humidification device includes a first flow path plate that forms a flow path of at least one of the supply fuel gas and the supply oxidant gas. A second flow path plate that forms a flow path of at least one of the exhaust fuel gas and the exhaust oxidant gas, and a flow path of the supply gas through a moisture transfer film The exhaust gas flow path inlet of at least one of the exhaust fuel gas and the exhaust oxidant gas of the first humidifier is connected to an exhaust gas flow path. A fuel cell system disposed above the outlet.   A fuel cell that generates power using a fuel gas and an oxidant gas; a fuel gas that is supplied to the fuel cell; a fuel gas such as an oxidant gas; and a oxidant gas that humidifies at least one of the supplied oxidant gas 2 is a fuel cell system in which the second humidifier is humidified using warm water that is cooling water. The second humidifier includes the supply fuel gas and the supply oxidation. A second flow path plate that forms a flow path of at least one of the supply gases and a first flow path plate that forms a flow path of the cooling water are connected to the supply gas through the moisture transfer film. A fuel cell system in which a plurality of the flow paths and the cooling water flow paths are stacked so that the cooling water flow path inlets of the second humidifier are disposed below the cooling water flow path outlets.   A fuel cell that generates power using a fuel gas and an oxidant gas, and a humidifier that humidifies at least one of a supply fuel gas such as a fuel gas and an oxidant gas supplied to the fuel cell and a supply oxidant gas. A first humidifier sandwiched between a first end plate and a second end plate, a second humidifier sandwiched between the second end plate and a third end plate. A humidifier is used, and the first humidifier uses moisture contained in at least one of exhaust fuel gas and exhaust oxidant gas such as the fuel gas and oxidant gas discharged from the fuel cell, respectively. In the fuel cell system in which the humidification is performed and the second humidification device is configured to perform the humidification using warm water that is cooling water, the first humidification device includes the supply fuel gas and the fuel cell system. Low supply of oxidant gas A first flow path plate that forms a flow path for at least one supply gas; and a second flow path plate that forms a flow path for at least one of the exhaust fuel gas and the exhaust oxidant gas. A plurality of stacked layers in which the flow path of the supply gas and the flow path of the exhaust gas are in contact with each other through a moisture transfer film, and the second humidifier is further configured to include the supply fuel gas and the supply oxidant. Supplying the second flow path plate that forms a flow path of at least one of the supply gases of the gas and the first flow path plate that forms the flow path of the cooling water through the moisture transfer film A plurality of gas flow paths and the cooling water flow path are stacked so as to be in contact with each other, and at least one of the exhaust fuel gas and the exhaust oxidant gas in the first humidifier is provided with an exhaust gas flow path inlet. Above the outlet of the exhaust gas passage Location fuel cell system.   The fuel cell system according to claim 3, wherein an inlet of the cooling water channel in the second humidifier is disposed below the outlet of the cooling water channel.

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