JP2006236831A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system controlling a plurality of flows of fluid supplied or supplied/exhausted at the same time to a reforming device or/and a fuel cell by a valve device of a structure solving problems unique to the system. <P>SOLUTION: By turning a valve body of a valve device to a communicating position, a plurality of kinds of fluid can be supplied at the same time to a reforming device or/and a fuel cell, so that there is no need of fitting a shut-off valve for each of the plurality of kinds of fluid to enable to cut off the number of valves used. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a fuel cell system that generates a reformed gas from supplied reforming fuel and steam, and supplies the reformed gas and cathode air to a fuel cell to generate electric power.

  In Patent Document 1, as shown in FIG. 1, methanol and water are heated and evaporated by an evaporator 13 using combustion gas generated in the combustion section 11, and the reformed catalyst is filled with the evaporated methanol and water vapor. The reforming unit 3 performs steam reforming to a so-called hydrogen-rich reformed gas, and the carbon monoxide contained in the reformed gas is reduced by the shift reaction unit 5 and the CO selective oxidation unit 7, and the CO selective oxidation unit The reformed gas from the compressor 7 and cathode air from the compressor are supplied to the fuel cell 9 to generate electricity, and the surplus reformed gas derived from the fuel cell 9 (hereinafter referred to as anode off-gas) is sent to the combustion unit 11 for combustion. A fuel cell system is described. In this fuel cell system, a first flow rate control valve 17 is provided between the reformed gas delivery port of the CO selective oxidation unit 7 and the fuel cell 9, and the reformed gas delivery port of the CO selective oxidation unit 7 and the combustion unit 11 are provided. The bypass circuit 15 to which the second flow rate control valve 19 is connected is connected between the first and second inlets. In this fuel cell system, during the steady operation, the first flow control valve 17 is opened and the second flow control valve 19 is closed, and all the reformed gas sent from the CO selective oxidation unit 7 is sent to the fuel cell 9. . However, when the load increases during acceleration or the like, the second flow rate control valve 19 is opened to reduce the supply amount of the reformed gas to the fuel cell 9 and take out the power from the fuel cell (power generation amount). By temporarily limiting and bypassing the reformed gas for that amount to the combustion unit 11, the amount of heat generated in the combustion unit 11 is increased to increase the evaporation amount of methanol and water, and the responsiveness of the reformer 1 is increased. It has improved.

  Generally, in such a fuel cell system, the methanol flow path and water flow path connected to the reformer 3 via the evaporator 13 and the air flow path connected to the selective oxidation reactor 7 In order to prevent intrusion of foreign matter into the mass part 1, each is stopped by an electromagnetic shut-off valve when stopped. At the start of operation, air is supplied to the selective oxidation reactor 7 almost simultaneously with the supply of methanol and water to the reformer 3 via the evaporator 13.

Thus, in order to supply methanol, water, and air to the fuel reforming unit 1 almost simultaneously, a rotary valve that controls a plurality of flow paths by rotating the ball valve 13 as shown in Patent Document 2 is provided as a fuel cell. Conventionally, it has not been used as a system electromagnetic shut-off valve, first and second flow control valves 17 and 19.
Japanese Patent Laid-Open No. 2001-23659 (page 3, FIG. 1) JP-A-9-329250 (page 3, FIG. 3)

  In the fuel cell system described in Patent Document 1, as described above, the electromagnetic shut-off valve and the first and second flow control valves respectively interposed in the methanol channel, the water channel, and the air channel must be provided. This increases the number of valves used. The electromagnetic shut-off valve presses the valve body against the valve seat by the spring force of the compression spring to shut off the passage, and the solenoid is pulled away from the valve seat against the spring force of the compression spring by the suction force of the solenoid. Therefore, when pressure is applied in the forward direction to press the valve body against the valve seat, the passage is surely blocked, but the valve body may leave the valve seat when strong pressure is applied in the opposite direction. . In addition, the fuel cell system uses a normally closed electromagnetic shut-off valve that closes when the operation is stopped or when the system is down and opens the shut-off valve during operation, so the solenoid must be energized during operation. Electricity consumed by the valve increases, and power generation efficiency decreases.

  Then, when the electromagnetic shut-off valves interposed in the methanol flow path, the water flow path, and the air flow path are shut off while the internal temperature of the fuel reforming section 1 is high as the fuel cell system stops operating, the fuel reforming section The inside of 1 becomes a negative pressure state due to a temperature drop, and it is difficult to open each electromagnetic shut-off valve at the start of operation. In addition, in the electromagnetic shut-off valve, the valve element is released from the valve seat in a short time due to the energization of the solenoid. Therefore, when the electromagnetic shut-off valve interposed in the air flow path is opened, the air suddenly becomes a selective oxidation reactor. 7 may cause catalyst deterioration, damage, and outflow of catalyst powder.

   An object of the present invention is to provide a fuel cell system that controls the flow of a plurality of fluids simultaneously supplied to and discharged from a reformer or / and a fuel cell by a valve device having a structure that solves a problem specific to the fuel cell system. .

  In order to solve the above problems, the structural feature of the invention according to claim 1 is that the reforming fuel and steam are supplied to the reforming section filled with the catalyst heated by the combustion gas generated in the combustion section. And a reformer that generates reformed gas by supplying CO selective oxidation air to the CO selective oxidation unit, and the reformer gas is introduced from the reformer into the reformed gas inlet for introducing the reformed gas into the anode electrode of the fuel cell. Reformed gas is supplied, cathode air is supplied to a cathode air introduction port for introducing cathode air to the cathode electrode of the fuel cell, and the combustion section is connected to an anode off gas outlet for extracting anode off gas from the anode electrode. In the fuel cell system, a valve body having a circular cross section is closely fitted in a valve hole formed in the valve housing so as to be rotatable about the rotation axis, and the outer peripheral surface of the valve housing and the front are When a plurality of sets of inflow passages and outflow passages that open to the valve holes are spaced apart from the valve housing and the valve body is positioned at the blocking position, the outer peripheral surface of the valve body is the plurality of sets. When the inflow passage and the outflow passage are blocked and the valve body is rotated to the communication position, a plurality of communication passages that respectively connect the plurality of sets of inflow passages and outflow passages simultaneously are provided in the valve body. A valve device is provided in which a body is rotated between the shut-off position and the communication position by a drive device, and each flow path of a plurality of types of fluids simultaneously supplied to the reforming device and / or the fuel cell Each of the outflow paths is connected to the inflow path, and each of the outflow paths is connected to the reformer or / and the fuel cell.

  The structural feature of the invention according to claim 2 is that, in claim 1, pumps for controlling the flow rate of the plurality of types of fluids are provided upstream of the inflow passages of the valve device. is there.

  The structural feature of the invention according to claim 3 is that, in claim 1 or 2, the plurality of types of fluids simultaneously supplied to the reformer or / and the fuel cell are the reforming fuel and the CO selection. Oxidized air, or the reformed gas and the cathode air, and the outflow paths are connected to the reformer and the CO selective oxidizer, or the reformed gas inlet and the cathode air inlet of the fuel cell, respectively. That is.

  According to a fourth aspect of the present invention, there is provided a reforming device that generates a reformed gas by being supplied with a reforming fuel and water vapor and filled with a catalyst heated by a combustion gas generated in a combustion section. The reformed gas is supplied from the reformer to the reformed gas inlet for introducing the reformed gas into the anode electrode of the fuel cell, and the cathode is introduced into the cathode air inlet for introducing the cathode air into the cathode electrode of the fuel cell. In a fuel cell system in which air is supplied and the combustion section is connected to an anode off-gas outlet through which anode off-gas is led out from the anode electrode, a valve body having a circular cross section is rotated around the rotation axis in a valve hole formed in the valve housing. The valve housing has first, second inflow passages, and first and second outflow passages that are rotatably fitted in close contact with each other and open to the outer peripheral surface of the valve housing and the valve hole, respectively. When the valve body is rotated to the shut-off position, the outer peripheral surface of the valve body closes the first, second inflow passage and the first and second outflow passages in the previous period, and the valve body is in the starting operation position. When rotated, the first inflow path and the second outflow path, the second inflow path and the first outflow path are communicated, and when rotated to the normal operation position, the first inflow path and the first outflow path One outflow path, a pair of communication passages that communicate the second inflow path and the second outflow path are provided in the valve body, and the valve body is set by the drive device to the cutoff position, the start operation position, and the normal operation position. The first inflow path is a reformed gas delivery port of the reformer, the first outflow path is a reformed gas inlet of the fuel cell, and the second inflow path is The anode off-gas outlet and the second outflow path are connected to the combustion section, respectively.

  In the invention according to claim 1 configured as described above, a plurality of types of fluids can be simultaneously supplied to the reforming device and / or the fuel cell by rotating the valve body of the valve device to the communication position. Therefore, it is not necessary to provide a shut-off valve for each of a plurality of types of fluids, and the number of valves used can be reduced. In addition, since the inflow passage and the outflow passage are closed by the outer peripheral surface of the valve body that is closely fitted in the valve hole, even if the differential pressure between the multiple inflow passages and the outflow passages becomes large, the valve body does not rotate. The valve can be easily opened by movement. Then, by rotating the valve body closely fitted in the valve hole to the communication position, the plurality of sets of inflow passages and outflow passages are communicated with each other, so that the valve bodies are held at the communication position with low power consumption. can do. Furthermore, since the communication area between the inflow path and the outflow path gradually increases as the valve body rotates, the reforming section and the CO selective oxidation section of the reformer, the anode electrode and the cathode electrode of the fuel cell, etc. The fluid can be prevented from entering, and deterioration of the catalyst or electrode, damage, and outflow of catalyst powder can be reduced.

  In the invention according to claim 2 configured as described above, a plurality of types of fluids are respectively sent out by controlling the flow rate by a pump and are simultaneously communicated by a plurality of communication passages of a valve body rotated to a communication position. Since it is sent through each set of inflow path and outflow path, a necessary amount of a plurality of types of fluids can be simultaneously supplied to the reformer or / and the fuel cell by a valve device having a simple configuration.

  In the invention according to claim 3 configured as described above, the reforming fuel and the CO selective oxidation air, or the reformed gas and the cathode air are used as the reforming unit and the CO selective oxidation unit of the reformer, or the fuel cell. Therefore, it is necessary to provide a shut-off valve in each flow path for reforming fuel and CO selective oxidation air or reforming gas and cathode air. Therefore, the number of valves used can be reduced. In particular, since the communication area between the inflow path and the outflow path gradually increases with the rotation of the valve body, the fluid is rapidly applied to the reforming section and the CO selective oxidation section of the reformer, or the anode and cathode electrodes of the fuel cell. Can be prevented, and catalyst deterioration, catalyst powder outflow, electrode deterioration, and damage can be reduced.

  In the invention according to claim 4 configured as described above, when the valve body of the valve device is rotated to the starting operation position, the reformed gas is supplied from the reformed gas delivery port of the reformer to the combustion section. When the fuel cell system is rotated to the normal operation position, the reformer gas is supplied to the fuel cell and the anode off gas is supplied from the fuel cell to the combustion section. The fluid flow channel communication relationship between the reformer and the fuel cell, which are required during operation, can be achieved by switching a single simple valve device.

  Embodiments of a fuel cell system according to the present invention will be described below. As shown in FIG. 1, the fuel cell system includes a fuel cell 11 and a reformer 12 that generates and supplies hydrogen gas necessary for the fuel cell 11. The reformed gas is supplied from the reformer 12 to the anode electrode of the fuel cell 11, and air from the outside is supplied to the cathode electrode of the fuel cell 11 by an air pump. The gas and oxygen gas in the cathode air react to generate power.

  The reformer 12 evaporates pure water supplied from a reforming unit 13 and a water pump 24 that are supplied with a hydrocarbon-based reforming fuel gas such as natural gas or LPG and steam to generate reformed gas. An evaporator 15 that generates water vapor to be supplied to the reforming unit 13, and a combustion unit that generates combustion gas for heating the reforming unit 13 and the evaporator 15 by mixing and burning combustion fuel gas and combustion air 14. Carbon monoxide contained in the reformed gas stacked at the lower part of the reforming unit 13 and generated at the reforming unit 13 and cooled by the heat exchanging unit 16 stacked at the lower part of the heat exchanging unit 16 CO shift unit 17 that removes CO, and a CO selective oxidation unit that is connected to CO shift unit 17 and further removes carbon monoxide contained in the reformed gas sent from CO shift unit 17 and supplies the fuel cell 11 from the outlet It is comprised from 18. The outlet of the CO selective oxidation unit 18 becomes the reformed gas outlet of the reformer 12. The reformed gas introduced into the anode electrode from the reformed gas introduction port of the fuel cell 11 reacts with oxygen gas in the cathode air introduced into the cathode electrode to generate power and become water, but it is an excess reformed gas. A certain anode off gas is sent from the anode off gas outlet of the fuel cell 11 to the combustion section 14 and burned.

  The reaction chamber 19 filled with the catalyst of the reforming unit 13 is surrounded by the heating chamber 20 of the combustion unit 14 at the top and outer periphery, and the burner 21 provided in the heating chamber 20 is a combustion fuel sent by a gas pump. The gas and combustion air sent by the air pump are mixed and burned to generate combustion gas. The combustion gas heats the catalyst in the reaction chamber 19 while flowing through the heating chamber 20, and then flows into the evaporator 15 to evaporate pure water. The reforming fuel gas pumped by the gas pump 22 and the water vapor generated by the evaporator 15 are mixed and introduced into the heat exchanging unit 16, preheated by the heat exchanging unit 16 and supplied to the reaction chamber 19 for combustion. A reformed gas is generated by a steam reforming reaction and a carbon monoxide shift reaction by a catalyst heated by the gas.

  In the heat exchange unit 16 and the CO selective oxidation unit 18 of the reforming device 21, the reforming fuel gas and the CO selective oxidizing air that are sent from the gas pump 22 and the air pump 23 while controlling the flow rate are supplied to the reforming fuel gas channel 25. And are supplied simultaneously through the air flow path 26. The reforming fuel gas passage 25 and the air passage 26 are provided with a valve device 27 for simultaneously connecting and closing both the passages 25 and 26.

  2 and 3, in the valve device 27, a seat member 29 is integrally fixed to an inner hole of a valve housing 28, and a ball valve body having a circular cross section is formed in a spherical valve hole 30 formed in the seat member 29. 31 is closely fitted so as to be rotatable around the rotation axis 32. The seat member 29 is vertically divided into two at the center of the spherical valve hole 30 by a plane perpendicular to the rotation axis 32, and the ball valve element 31 is sandwiched between the upper and lower seat members 29 a and 29 b and closely fitted into the spherical valve hole 30. Has been. The valve housing 28 and the upper and lower seat members 29a and 29b are perforated by passages 33 and 34 extending in parallel at an equal distance from a plane perpendicular to the rotation axis 32 and passing through the center of the ball valve body 31. Has been. The inflow passages 33 and 34 are divided by the valve hole 30 into first and second inflow passages 33a and 34a and first and second outflow passages 33b and 34b. As described above, the inflow path 33a and the outflow path 33b each having one end opened on both outer surfaces at the upper and lower positions of the valve housing 28 and the other end opened on the left and right inner peripheral surfaces of the valve holes 30 of the upper and lower seat members 29a and 29b, respectively. Two sets of inflow passages 34a and outflow passages 34b are formed in the valve housing 28 and the upper and lower seat members 29a, 29b so as to be spaced apart in the direction of the rotation axis 32. The inflow path 33a and the outflow path 33b, and the inflow path 34a and the outflow path 34b are blocked by the outer peripheral surface of the ball valve body 31 when the ball valve body 31 is rotated to the blocking position in FIG. When the ball valve body 31 is rotated to the communication position shown in FIG. 2, the ball valve body 31 has two inflow passages 33a and an outflow passage 33b, and an inflow passage 34a and an outflow passage 34b. Communication holes (communication paths) 35 and 36 are provided. The discharge ports of the gas pump 22 and the air pump 23 are connected to the inflow channels 33a and 34a, and the reforming unit 13 is connected to the outflow channels 33b and 34b through the heat exchange unit 16 of the reformer 21, A CO selective oxidation unit 18 is connected.

   A valve shaft 37 protruding from the ball valve body 31 on the rotation axis 32 passes through the upper seat member 29 a and is connected to a motor 39 via a speed reduction mechanism 38. A torsion coil spring 40 is interposed between the valve shaft 37 and the valve housing 28, and the ball valve body 31 is rotated to the shut-off position by the spring force of the torsion coil spring 40 when the motor 39 is in an inactive state. The ball valve body 31 is rotated from the blocking position to the communication position by the motor 39 through the speed reduction mechanism 38 against the spring force of the torsion coil spring 40.

   When the fuel cell system is stopped, the reformed gas delivery port of the reformer 12, the reformed gas inlet and the anode off-gas outlet of the fuel cell 11 are blocked, and during the start-up operation, the CO selective oxidation unit 18 of the reformer 12. From the reformed gas delivery pipe 41, the reformed gas sent out from the fuel cell 11 bypasses the fuel cell 11 and is sent to the combustion section 14 through the off-gas channel 42. During normal operation, the reformed gas is sent to the reformed gas channel. The anode offgas supplied to the fuel cell 11 through 41 and delivered from the fuel cell 11 is sent to the combustion unit 14 through the offgas flow path 42. In order to form such a flow path, a valve device 43 is interposed across the reformed gas flow path 41 and the off-gas flow path 42.

  As shown in FIG. 4, the valve device 43 has a seat member 45 integrally fixed to the inner hole of the valve housing 44, and a ball valve body 47 having a circular section in a spherical valve hole 46 formed in the seat member 45. It is closely fitted so as to be rotatable about the rotation axis 48. The seat member 45 is divided into left and right at the center of the spherical valve hole 46 by a plane parallel to the rotation axis 48, and the ball valve body 47 is sandwiched between the left and right seat members 45a and 45b and is closely fitted in the spherical valve hole 46. Has been. The valve housing 44 and the left and right seat members 45a and 45b are parallel to each other at an equal distance from the center O of the ball valve body 47 in a plane perpendicular to the rotation axis 48 and including the center O of the ball valve body 47. , 50 are drilled through. The flow paths 49 and 50 are divided by the valve hole 46 into first and second inflow paths 49a and 50a and first and second outflow paths 49b and 50b that open to both outer side surfaces of the valve housing 44 and the valve hole 46, respectively. ing. In the ball valve body 47, when the ball valve body 47 is rotated to the blocking position of FIG. 5A, the outer peripheral surface of the valve body is the first and second inflow passages 49a and 50a and the first and second inflow passages. When the outflow passages 49b and 50b are closed and the ball valve body 47 is rotated to the starting operation position of FIG. 5B, the first inflow passage 49a, the second outflow passage 50b, the second inflow passage 50a, and the first When the outflow passage 49b is communicated and the ball valve body 47 is rotated to the normal operation position in FIG. 5C, the first inflow passage 49a and the first outflow passage 49b, the second inflow passage 50a and the second outflow passage 50b. Are provided with a pair of communication holes (communication passages) 51 and 52. The first inflow passage 49a and the first outflow passage 49b are respectively connected to the reformed gas delivery port of the reformer 12 and the reformed gas introduction port of the fuel cell 11 by the reformed gas channel 41, and the second inflow channel 50a. The second outflow passage 50 b is connected to the anode offgas outlet of the fuel cell 11 and the combustion unit 14 by an offgas passage 42.

  A valve shaft 53 protruding from the ball valve body 47 on the rotation axis 48 passes through the contact portions of the left and right seat members 45a and 45b and is connected to a motor 55 via a speed reduction mechanism 54. A torsion coil spring 56 is interposed between the valve shaft 51 and the valve housing 44, and the ball valve body 47 is rotated to the cut-off position by the spring force of the torsion coil spring 56 when the motor 55 is in an inactive state. The ball valve body 47 is rotated by the motor 55 from the blocking position to the starting operation position and the normal operation position against the spring force of the torsion coil spring 56 via the speed reduction mechanism 54.

   Next, the operation of the above embodiment will be described. When the fuel cell system is stopped, the valve devices 27 and 43 are moved to the cutoff position by the spring force of the torsion coil springs 40 and 56, and the inflow passage 33a, the outflow passage 33b, and the inflow passage 34a. Each communication of the outflow path 34b and the first inflow path 49a, the first outflow path 49b, the second inflow path 50a, and the second outflow path 50b are blocked by the outer peripheral surfaces of the ball valve bodies 31 and 47. As a result, the reforming fuel gas passage 25 and the air passage 26 connected to the reforming section 13 and the CO selective oxidation section 18 of the reformer 12 are shut off, and the outlet of the CO selective oxidation section 18, and The reformed gas inlet for introducing the reformed gas into the anode electrode of the fuel cell 11 and the anode offgas outlet for extracting the anode offgas from the anode electrode are closed, and the reformer 12 and the fuel cell 11 are shut off from the outside, The internal pressure decreases due to the cooling of the gas sealed in. In this case, since the second outflow passage 50b is blocked by the outer peripheral surface of the ball valve body 47 that is closely fitted in the valve hole 46, the second outflow passage 50b and the second outflow passage 50b can be 1 and the 2nd inflow passages 49a and 50a can be interrupted | blocked reliably.

   When the start-up operation of the fuel cell system is commanded, the ball valve body 31 of the valve device 27 is rotated to the communication position against the spring force of the torsion coil spring 40 by the motor 39, and the flow rate is controlled by the gas pump 22 and sent out. The reforming fuel gas is supplied to the reforming unit 13 of the reformer 21 through the heat exchange unit 16 through the inflow path 33a, the communication hole 35, and the outflow path 33b, and the flow rate is controlled by the air pump 23. The sent CO selective oxidation air is simultaneously supplied to the CO selective oxidation unit 18 through the inflow path 34a, the communication hole 36, and the outflow path 34b. At this time, since the communication area between the inflow passages 33a and 34a and the outflow passages 33b and 34b gradually increases as the ball valve body 31 rotates, the reforming unit 13 and the CO selective oxidation unit 18 of the reforming device 12 are suddenly increased. Thus, the reforming fuel gas and the reformed gas do not enter, and the deterioration, damage and outflow of the catalyst powder can be reduced. In addition, the gas sealed in the reformer 12 is cooled by stopping the operation of the fuel cell system, the internal pressure is lowered, and the differential pressure between the inflow paths 33a, 34a and the outflow paths 33b, 34b is increased. Even in this case, the valve device 27 can be easily opened by the rotation of the ball valve body 31.

   Combustion fuel gas and combustion air are supplied to the burner 21 of the combustion section 14 and combusted. The generated combustion gas flows through the heating chamber 20 to heat the catalyst of the reforming section 13, and steam is generated by the evaporator 15. Generate. The reforming fuel gas supplied by the gas pump 22 and the water vapor generated by the evaporator 15 are mixed and introduced into the heat exchange unit 16, preheated by the heat exchange unit 16 and supplied to the reforming unit 13, A reformed gas is generated by a steam reforming reaction and a carbon monoxide shift reaction by a catalyst heated by the combustion gas. The reformed gas derived from the reforming unit 13 is reduced in concentration of carbon monoxide gas by the CO shift unit 17 and the CO selective oxidation unit 18 to which CO selective oxidation air is supplied from the air pump 23.

   Then, the ball valve body 47 of the valve device 43 is rotated to the starting operation position by the motor 55 against the spring force of the torsion coil spring 56, and the reformed gas sent from the CO selective oxidation unit 18 is bypassed to the combustion unit 14. Then, the reformed gas inlet and the anode offgas outlet of the fuel cell 11 are communicated. As a result, during the start-up operation in which the concentration of carbon monoxide gas contained in the reformed gas sent from the CO selective oxidation unit 18 is higher than a predetermined value, the reformed gas sent from the CO selective oxidation unit 18 flows into the first inflow. The fuel is bypassed by the combustion unit 11 through the passage 49a, the communication hole 51, and the second outflow passage 50b and burned. It is detected that the catalyst temperature of the CO selective oxidation unit 18 is equal to or higher than a predetermined value, the system becomes stable, and the concentration of carbon monoxide gas contained in the reformed gas sent from the CO selective oxidation unit 18 is lower than the predetermined value. In order to switch from the starting operation to the normal operation, the ball valve body 47 of the valve device 43 is rotated to the normal operation position against the spring force of the torsion coil spring 56 by the motor 55, and from the CO selective oxidation unit 18. The sent reformed gas is supplied to the fuel cell 11 through the reformed gas channel 41, and the anode offgas sent from the fuel cell 11 is sent to the combustion unit 14 through the offgas channel 42. At this time, since the communication areas of the first and second inflow passages 49a and 50a and the first and second outflow passages 49b and 50b gradually increase as the ball valve body 47 rotates, a large amount of reformed gas is generated. The fuel cell 11 is suddenly sucked in, and the stable state of the reformer 12 is not broken, so that the concentration of carbon monoxide gas contained in the reformed gas does not increase.

   In the above embodiment, the valve device 27 is interposed in the reforming fuel gas flow path 25 and the air flow path 26, but the reformed gas delivery port of the reformer 12 is provided in the inflow passages 33 a and 34 a of the valve device 27. And the air pump are connected, the outflow paths 33b and 34b are connected to the reformed gas inlet and the cathode air inlet of the fuel cell 11, and the reformed gas and the cathode air are simultaneously supplied to the anode electrode and the cathode electrode of the fuel cell 11. You may do it.

   In the valve device 27 of the above embodiment, two sets of inflow passages and outflow passages are formed in the valve housing 28 and the upper and lower seat members 29a and 29b so as to be spaced apart in the direction of the rotation axis 32. And the outlets of the gas pump 22, the air pump 23 and the water pump 24 are connected to the respective inflow passages, and the ball valve body 31 is rotated to the blocking position in these three inflow passages and outflow passages. Then, when the ball valve body 31 is closed at the outer peripheral surface and rotated to the communication position, the ball valve body 31 is simultaneously communicated by three communication holes (communication passages) provided in the ball valve body 31 and sent from the gas pump 22. The reformed gas fuel is sent to the reforming unit 13 through the heat exchange unit 16, pure water sent from the water pump 24 is sent to the evaporator 15, and CO selective oxidation air sent from the air pump is sent to the CO selective oxidation unit 18 at the same time. You may do it.

   In the valve device 43 of the above embodiment, when the ball valve body 47 is rotated to the closed position, the ball valve body 47 is closed at the inner peripheral surface of the valve hole 46 and is rotated to the starting operation position. The first inflow path 49a and the second outflow path 50b, the second inflow path 50a and the first outflow path 49b communicate with each other, and when rotated to the normal operation position, the first inflow path 49a and the first outflow path 49b A pair of communication holes 51 and 52 for communicating the second inflow path 50a and the second outflow path 50b are formed, but the ball valve body 47 is formed at the same position as the communication hole 51 as shown in FIG. A communication hole 57 that opens to the outer peripheral surface and opens to the outer peripheral surface with a slight gap from the opening to the outer peripheral surface of the communication hole 52 may be formed. By forming the communication hole 57, the ball valve body 47 is moved from the starting operation position to a position immediately before the first and second inflow passages 49a and 50a and the first and second outflow passages 49b and 50b start to communicate. , The first inflow path 49a and the second outflow path 50b are in communication with each other through the communication hole 57, and the bypass of the reformed gas sent from the CO selective oxidation unit 18 to the combustion unit 14 is bypassed. Will continue. Thereafter, the communication areas of the first inflow path 49a and the first outflow path 49b, and the second inflow path 50a and the second outflow path 50b gradually increase as the ball valve body 47 rotates at an appropriate speed, and the first inflow path The communication area between 49a and the second outflow passage 50b gradually decreases. This gradually increases the communication area between the reformer 12 and the reformed gas inlet of the fuel cell 11 and the communication area between the offgas outlet and the combustion unit 14 when switching from the start-up operation to the normal operation. Since the communication area between the reformer 12 and the combustion unit 14 via the communication hole 57 is gradually reduced and then shut off, the anode off-gas flow temporarily stops, causing the burner 21 to misfire or unstable combustion. The increase in emissions due to can be suppressed.

   In the said embodiment, although the valve body of the valve apparatuses 27 and 43 was used as the spherical ball | bowl valve body, the valve body should just be a valve body with a circular cross section with the rotary body around a rotating shaft line.

   In the above embodiment, the ball valve body 31 is provided with two communication holes 35 and 36. However, when the valve body is rotated to the communication position, the inflow path 33a, the outflow path 33b, the inflow path 34a, Two semicircular communication grooves that respectively communicate with the outflow passages 34b at the same time are spaced apart from the outer peripheral surface of the spherical or cylindrical valve body in the rotational axis direction of the valve body in a plane perpendicular to the rotational axis. It may be engraved. In the above embodiment, the ball valve body 47 is provided with the pair of communication holes 51 and 52. However, when the valve body is rotated to the starting operation position, the first inflow passage 49a and the second outflow passage are provided. 50b, the second inflow path 50a and the first outflow path 49b communicate with each other and rotated to the normal operation position, the first inflow path 49a and the first outflow path 49b, and the second inflow path 50a and the second outflow path 50b. A pair of arc-shaped communication grooves that communicate with each other may be formed on the outer peripheral surface of the spherical or cylindrical valve body in a plane perpendicular to the rotation axis of the valve body.

   In the above embodiment, the reformer reforms the supplied reforming fuel gas and steam to generate reformed gas, but reforms the reforming methanol, which is the reforming fuel gas. A reformer that generates a quality gas may be used.

1 is a schematic diagram showing an outline of a fuel cell system according to an embodiment of the present invention. The figure which shows the valve apparatus used for a fuel cell system. The cross-sectional view of the valve apparatus by which the ball valve body was rotated to the interruption | blocking position. The figure which shows the other valve apparatus used for a fuel cell system. The figure which shows the state which the ball valve body of the other valve apparatus rotated to each position. The cross-sectional view of 2nd Embodiment of another valve apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Fuel cell, 12 ... Reformer, 13 ... Reforming part, 14 ... Combustion part, 15 ... Evaporator, 16 ... Heat exchange part, 17 ... CO shift part, 18 ... CO selective oxidation part, 19 ... Reaction chamber , 20 ... heating chamber, 21 ... burner, 22 ... gas pump, 23 ... air pump, 24 ... water pump, 25 ... reforming fuel gas passage, 26 ... air passage, 27, 43 ... valve device, 28, 44 ... Valve housing, 29, 45 ... seat member, 30, 46 ... valve hole, 31, 47 ... ball valve element, 32, 48 ... rotation axis, 33, 34, 49, 50 ... flow path, 33a, 34a, 49a, 50a ... Inflow passage, 33b, 34b, 49b, 50b ... Outflow passage, 35, 36, 51, 52, 57 ... Communication hole (communication passage), 37, 53 ... Valve shaft, 38, 54 ... Deceleration mechanism, 39, 55 ... Motor, 40, 56 ... Torsion coil spring, 41 ... Reformed gas flow path, 4 ... off-gas flow path.

Claims (4)

A reforming fuel and steam are supplied to the reforming section filled with a catalyst heated by the combustion gas generated in the combustion section, and CO selective oxidation air is supplied to the CO selective oxidation section to generate reformed gas. The reformed gas is supplied from the reformer to a reformed gas inlet for introducing the reformed gas into the anode electrode of the fuel cell, and cathode air is introduced into the cathode electrode of the fuel cell. In the fuel cell system in which cathode air is supplied to the inlet, and the combustion unit is connected to the anode offgas outlet for extracting the anode offgas from the anode electrode,
A valve body having a circular cross section is closely fitted in a valve hole formed in the valve housing so as to be rotatable about a rotation axis, and a set of an inflow path and an outflow path that respectively open to the outer peripheral surface of the valve housing and the valve hole. When a plurality of sets are drilled apart from the valve housing and the valve bodies are positioned at the shut-off position, the outer peripheral surface of the valve body blocks the plurality of sets of inflow passages and outflow passages, and the valve bodies communicate with each other. When the valve body is rotated to a position, a plurality of communication passages that simultaneously communicate the plurality of sets of inflow passages and outflow passages are provided in the valve body, and the valve body is provided between the shut-off position and the communication position by a driving device. A valve device that is rotated by
Each flow path of a plurality of types of fluids supplied simultaneously to the reformer and / or the fuel cell is connected to each inflow path, and each outflow path is connected to the reformer and / or the fuel cell, respectively. A fuel cell system characterized by being connected. 2. The fuel cell system according to claim 1, wherein a pump for controlling the flow rate of each of the plurality of types of fluids is provided upstream of each inflow path of the valve device. 3. The plurality of types of fluids simultaneously supplied to the reformer and / or the fuel cell according to claim 1 or 2, wherein the reforming fuel and the CO selective oxidation air, or the reformed gas and the cathode air are used. The fuel cell system is characterized in that each of the outflow paths is connected to the reforming unit and the CO selective oxidation unit, or the reformed gas inlet and the cathode air inlet of the fuel cell, respectively. A reformer is provided that is charged with a catalyst heated by combustion gas generated in the combustion section and is supplied with reforming fuel and water vapor to generate reformed gas, and introduces the reformed gas into the anode electrode of the fuel cell. The reformed gas is supplied to the reformed gas inlet from the reformer, the cathode air is supplied to the cathode air inlet for introducing the cathode air to the cathode electrode of the fuel cell, and the anode off gas is led out from the anode electrode. In the fuel cell system in which the combustion unit is connected to the anode off-gas outlet,
A valve body having a circular cross section is closely fitted in a valve hole formed in the valve housing so as to be rotatable about a rotation axis, and the first and second inflow passages open to the outer peripheral surface of the valve housing and the valve hole, respectively. When the first and second outflow passages are drilled in the valve housing and the valve body is turned to the shut-off position, the outer peripheral surface of the valve body is the first, second inflow passage and the first and second in the previous period. When the outflow path is closed and the valve body is rotated to the starting operation position, the first inflow path and the second outflow path, the second inflow path and the first outflow path are communicated, and the normal operation position is established. When rotated, the valve body is provided with a pair of communication passages that connect the first inflow path and the first outflow path, and the second inflow path and the second outflow path. A valve device that is rotated between the shut-off position, the start-up operation position, and the normal operation position;
The first inflow path is the reformed gas delivery port of the reformer, the first outflow path is the reformed gas inlet of the fuel cell, the second inflow path is the anode offgas outlet, and the second outflow path Are each connected to the combustion section.

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