JP6208463B2 - Fuel cell device - Google Patents

Description

  The present invention relates to a fuel cell device.

  In recent years, as a next-generation energy, a cell stack in which a plurality of fuel cells that can obtain electric power using a fuel gas (hydrogen-containing gas) and an oxygen-containing gas (air) are arranged is known. Various fuel cell modules in which a cell stack is stored in a storage container and fuel cell devices in which a fuel cell module is stored in an outer case have been proposed.

  Such a fuel cell device is provided with a reformer that reforms raw fuel such as natural gas or kerosene to generate fuel gas to be supplied to the fuel cell, and the reformer is efficient. It is known to perform steam reforming, which is a good reforming reaction.

  Further, in such a cogeneration system in which a fuel cell device and a water heater are combined, heat exchange is performed between the exhaust gas discharged from the fuel cell module and water, and the water contained in the exhaust gas at the time of this heat exchange. Is produced as condensed water.

  Condensed water generated by heat exchange is subsequently generated by a water treatment device, and the generated pure water is temporarily stored in a water tank and then supplied to a reformer by a water pump. In the reformer, steam reforming is performed using water supplied from a water pump. After the generated fuel gas containing water vapor is used for power generation in the fuel cell, it is discharged from the fuel cell module. With the configuration described above, a fuel cell device capable of water self-sustained operation is provided (for example, see Patent Document 1).

JP 2009-9808 A

  By the way, in such a fuel cell device, bubbles may be generated in the connection pipe connecting the water treatment device and the water tank, the flow of water is blocked by the bubbles, and the water level of the water tank is lowered. In some cases, the operation of the fuel cell device may be stopped.

  Therefore, an object of the present invention is to provide a fuel cell device that can suppress blocking of water flowing through a connection pipe that connects a water treatment device and a water tank, and has improved long-term reliability.

A fuel cell device of the present invention includes a fuel cell that generates power with a fuel gas and an oxygen-containing gas, a reformer capable of a steam reforming reaction for generating fuel gas to be supplied to the fuel cell, and A water treatment device for purifying the water supplied to the reformer, a water tank for storing the water treated by the water treatment device and supplied to the reformer, the water treatment device, and the water A connection pipe connecting the water tank; a water flow changing member provided in or on the connection pipe for changing the flow of water flowing through the connection pipe; and a water level in the water tank in the water tank. A water level detecting member for detecting the water level, and a control device for operating the water flow changing member when the water level in the water tank detected by the water level detecting member is equal to or lower than a predetermined first water level. It is characterized by that.

The fuel cell device of the present invention includes a water flow changing member that changes the water flow of the water flowing through the connection pipe connecting the water treatment device and the water tank, and is thus supplied from the water treatment device to the water tank via the connection pipe. Even if bubbles are included in the water, the water flowing through the connection pipe connecting the water treatment device and the water tank is blocked by changing the water flow of the water flowing through the connection pipe by the water flow changing member. The fuel cell device can be suppressed and the long-term reliability can be improved.

It is a block diagram which shows an example of a structure of a fuel cell system provided with the fuel cell apparatus of this embodiment. It is an external appearance perspective view which shows an example of the fuel cell module which comprises the fuel cell system shown in FIG. FIG. 3 is a cross-sectional view of the fuel cell module shown in FIG. 2. It is a conceptual diagram shown about the water treatment apparatus which comprises the fuel cell apparatus of this embodiment, a water tank, and connection piping which connects a water treatment apparatus and a water tank, and provided the water flow change member which is a rotary body in connection piping. It is a conceptual diagram which shows an example. FIG. 2 is a conceptual diagram showing a water treatment device, a water tank, and a connection pipe connecting the water treatment device and the water tank constituting the fuel cell device of the present embodiment. A vibrating body that vibrates the connection pipe is connected to the connection pipe. It is a conceptual diagram which shows the example provided. It is a conceptual diagram shown about the heat exchanger which comprises the fuel cell apparatus of this embodiment, a water treatment apparatus, a water tank, and the connection piping which connects a water treatment apparatus and a water tank, and connects a heat exchanger and a water treatment apparatus It is a conceptual diagram which shows the example which provided the valve in the condensed water supply pipe | tube. It is a conceptual diagram which shows the example which provided the water level detection member in the water tank shown in FIG. It is a flowchart which shows an example of the operating method of the fuel cell apparatus of this embodiment.

  FIG. 1 is a configuration diagram illustrating an example of a configuration of a fuel cell system including the fuel cell device of the present embodiment. The fuel cell system shown in FIG. 1 includes a power generation unit that is an example of the fuel cell device of the present embodiment, a hot water storage unit that stores hot water after heat exchange, and a circulation pipe that circulates water between these units. It is composed of In the following drawings, the same components are described using the same reference numerals.

  A power generation unit shown in FIG. 1 includes a cell stack 5 formed by combining a plurality of fuel cells having a fuel electrode layer, a solid electrolyte layer, and an oxygen electrode layer, a raw fuel supply unit 1 that supplies raw fuel such as city gas, and the like. An oxygen-containing gas supply unit 2 for supplying oxygen-containing gas to the fuel cells constituting the stack 5 and a reformer 3 for steam-reforming the raw fuel with the raw fuel and steam are provided. In the power generation unit shown in FIG. 1, a fuel cell module 4 (hereinafter sometimes referred to as a module) is configured by storing the cell stack 5 and the reformer 3 in a storage container. It is shown surrounded by a two-dot chain line. Although not shown in FIG. 1, a purification device for purifying exhaust gas that has not been used for power generation discharged from the cell stack 5 and an ignition device for burning fuel gas that has not been used for power generation. Can be provided.

  Further, in the power generation unit shown in FIG. 1, a circulation pipe 15 that circulates water to a heat exchanger 8 that performs heat exchange between exhaust gas (exhaust heat) generated by power generation of fuel cells constituting the cell stack 5 and water. A water treatment device 9 for treating the condensed water generated in the heat exchanger 8 with pure water, and a water tank 11 for storing water (pure water) treated with the water treatment device 9 are provided. The water tank 11 and the heat exchanger 8 are connected by a condensed water supply pipe 10. In addition, as the water treatment apparatus 9, it is preferable to use an ion exchange resin apparatus provided with an ion exchange resin.

  The water stored in the water tank 11 is supplied to the reformer 3 by a water pump 12 provided in a water supply pipe 13 that connects the water tank 11 and the reformer 3.

  Further, the power generation unit shown in FIG. 1 converts the DC power generated by the module 4 into AC power, and adjusts the supply amount of the converted electricity to the external load (power conditioner). 6. Control device 7 for controlling the operation of various devices described later in addition to the outlet water temperature sensor 14 for measuring the water temperature of the water (circulated water flow) provided at the outlet of the heat exchanger 8 and flowing through the outlet of the heat exchanger 8 The power generation unit is configured together with a circulation pump 17 that circulates water in the circulation pipe 15. And each apparatus which comprises these electric power generation units can be set as a fuel cell apparatus with easy installation, carrying, etc. by accommodating in an exterior case. The hot water storage unit includes a hot water storage tank 16 for storing hot water after heat exchange.

  Here, an operation method of the fuel cell system shown in FIG. 1 will be described.

  In generating fuel gas necessary for power generation of the cell stack 5, the control device 7 operates the raw fuel supply unit 1 and the water pump 12. As a result, raw fuel (natural gas, kerosene, etc.) and water are supplied to the reformer 3, and by performing steam reforming in the reformer 3, a fuel gas containing hydrogen is generated and the fuel cell. Supplied to the fuel electrode layer side.

  On the other hand, the control device 7 operates the oxygen-containing gas supply unit 2 to supply oxygen-containing gas (air) to the oxygen electrode layer side of the fuel cell.

  The control device 7 operates an ignition device (not shown) in the module 4 to burn fuel gas that has not been used for power generation of the cell stack 5. Thereby, the temperature in the module (the temperature of the cell stack 5 and the reformer 3) rises, and efficient power generation can be performed.

  The exhaust gas generated with the power generation of the cell stack 5 is purified by the purification device, then supplied to the heat exchanger 8 and heat-exchanged with water flowing through the circulation pipe 15. Hot water generated by heat exchange in the heat exchanger 8 flows through the circulation pipe 15 and is stored in the hot water storage tank 16. On the other hand, water contained in the exhaust gas discharged from the cell stack 5 by heat exchange in the heat exchanger 8 becomes condensed water and is supplied to the water treatment device 9 through the condensed water supply pipe 10. The condensed water is made pure water by the water treatment device 9 and supplied to the water tank 11. The water stored in the water tank 11 is supplied to the reformer 3 by the water pump 12 via the water supply pipe 13. Thus, water self-sustained operation can be performed by effectively using condensed water.

  In the above-described example, the fuel cell device configured to supply only the condensed water generated by the heat exchanger 8 to the reformer 3 has been described. Can also be used. In this case, as a water treatment device for treating impurities contained in tap water, for example, an activated carbon filter, a reverse osmosis membrane device, an ion exchange resin device, etc. are connected in this order to efficiently purify pure water. be able to. In addition, also when using tap water, each apparatus is connected so that the pure water produced | generated with the water treatment apparatus may be stored in the water tank 11. FIG.

  Next, an example of the module 4 shown in FIG. 1 will be described. 2 and 3 show an example of the module 4 constituting the fuel cell device of the present embodiment, FIG. 2 is an external perspective view showing the module 4, and FIG. 3 is a sectional view of the module 4 shown in FIG. is there.

In the module 4 shown in FIG. 2, columnar fuel cells 19 having gas flow paths (not shown) through which fuel gas flows are arranged in a row inside the storage container 18. The adjacent fuel cells 19 are electrically connected in series via current collecting members (not shown), and the lower end of the fuel cells 19 is connected to an insulating bonding material (not shown) such as a glass sealant. 2) a cell stack device 2 having two cell stacks 5 fixed to the manifold 20
1 is housed. At both ends of the cell stack 5, conductive members having electrical lead portions for collecting the electricity generated by the power generation of the cell stack 5 (fuel cell 19) and drawing it outside are disposed ( Not shown). 2 shows the case where the cell stack device 21 includes two cell stacks 5, the number can be changed as appropriate. For example, even if only one cell stack 5 is provided. Good. The storage container 18 is provided with a thermocouple 28 that is a temperature sensor for measuring the temperature of the module 4.

  In FIG. 2, the fuel battery cell 19 is a hollow flat plate type having a gas flow path through which fuel gas flows in the longitudinal direction. A fuel electrode layer, a solid electrolyte is formed on the surface of a support having the gas flow path. A solid oxide fuel cell 19 in which a layer and an oxygen electrode layer are sequentially laminated is illustrated. In addition, in the fuel battery cell 19, it is also possible to have a shape having a gas flow path through which the oxygen-containing gas flows in the longitudinal direction. In this case, the oxygen electrode layer, the solid electrolyte layer, and the fuel electrode layer are sequentially arranged from the inside. The configuration of the module 4 may be changed as appropriate. Furthermore, the fuel cell is not limited to the hollow plate type, and may be a plate type or a cylindrical type, for example, and it is preferable to change the shape of the storage container 18 as appropriate.

  Further, in the module 4 shown in FIG. 2, in order to obtain the fuel gas used in the power generation of the fuel battery cell 19, the raw fuel such as city gas supplied through the raw fuel supply pipe 25 is reformed to produce the fuel gas. A reformer 3 for generating gas is disposed above the cell stack 5. In addition, the reformer 3 can have a structure capable of performing steam reforming, which is an efficient reforming reaction, and a reforming unit 23 for vaporizing water and reforming raw fuel into fuel gas. And a reforming section 22 in which a reforming catalyst (not shown) is disposed.

  The fuel gas (hydrogen-containing gas) generated by the reformer 3 is supplied to the manifold 20 via the fuel gas circulation pipe 24 and is supplied from the manifold 20 to the gas flow path provided inside the fuel battery cell 19. Supplied. The configuration of the cell stack device 21 can be changed as appropriate depending on the type and shape of the fuel battery cell 19. For example, the reformer 3 can be included in the cell stack device 21.

  FIG. 2 shows a state in which a part (front and rear surfaces) of the storage container 18 is removed and the cell stack device 21 stored inside is taken out rearward. Here, in the module 4 shown in FIG. 2, the cell stack device 21 can be slid and stored in the storage container 18.

  The reaction container 18 is disposed between the cell stacks 5 juxtaposed to the manifold 20 and is reacted inside the storage container 18 so that the oxygen-containing gas flows laterally from the lower end portion toward the upper end portion of the fuel cell 19. A gas introduction member 26 is disposed.

  As shown in FIG. 3, the storage container 18 constituting the module 4 has a double structure having an inner wall 29 and an outer wall 30, and an outer frame of the storage container 18 is formed by the outer wall 30, and a cell stack is formed by the inner wall 29. A power generation chamber 31 that houses the device 21 is formed. Further, in the storage container 18, a reaction gas flow path 36 is supplied between the inner wall 29 and the outer wall 30 from the bottom of the module 4 and through which oxygen-containing gas introduced into the fuel cell 19 flows. The oxygen-containing gas is supplied from an oxygen-containing gas supply port (not shown) provided at the bottom of the module 4 and flows through the reaction gas channel 36.

Here, the storage container 18 is provided with an oxygen-containing gas inlet (not shown) for allowing oxygen-containing gas to flow into the upper end side from the upper portion of the storage container 18 and a flange portion 39, and a fuel at the lower end portion. A reaction gas introduction member 26 provided with a reaction gas outlet 32 for introducing an oxygen-containing gas at the lower end of the battery cell 19 is inserted through the inner wall 29 and fixed. A heat insulating member 33 is disposed between the flange portion 39 and the inner wall 29.

  In FIG. 3, the reaction gas introduction member 26 is disposed so as to be positioned between two cell stacks 5 juxtaposed inside the storage container 18, but is appropriately disposed depending on the number of cell stacks 5. be able to. For example, when only one cell stack 5 is stored in the storage container 18, two reaction gas introduction members 26 can be provided so that the cell stack 5 is sandwiched from both side surfaces.

  Further, in the power generation chamber 31, the temperature in the module 4 is maintained at a high temperature so that the heat in the module 4 is extremely dissipated and the temperature of the fuel cell 19 (cell stack 5) is lowered and the power generation amount is not reduced. A heat insulating member 33 is appropriately provided.

  The heat insulating member 33 is preferably disposed in the vicinity of the cell stack 5. In particular, the heat insulating member 33 is disposed on the side surface side of the cell stack 5 along the arrangement direction of the fuel cells 19, and the fuel cell unit on the side surface of the cell stack 5. It is preferable to arrange the heat insulating member 33 having a width equal to or greater than the width along the 19 arrangement directions. In addition, it is preferable to arrange the heat insulating members 33 on both side surfaces of the cell stack 5. Thereby, it can suppress effectively that the temperature of the cell stack 5 falls. Furthermore, the oxygen-containing gas introduced from the reaction gas introduction member 26 can be suppressed from being discharged from the side surface side of the cell stack 5, and the flow of the oxygen-containing gas between the fuel cells 19 constituting the cell stack 5 can be reduced. Can be promoted. In the heat insulating members 33 arranged on both side surfaces of the cell stack 5, the flow of the oxygen-containing gas supplied to the fuel cell 19 is adjusted, and the longitudinal direction of the cell stack 5 and the stacking direction of the fuel cell 19 are adjusted. An opening 34 is provided to reduce the temperature distribution at. Note that the opening 34 may be formed by combining a plurality of heat insulating members 33.

  Further, an exhaust gas inner wall 35 is provided on the inner side of the inner wall 29 along the arrangement direction of the fuel cells 19, and the exhaust gas in the power generation chamber 31 extends from above between the inner wall 29 and the exhaust gas inner wall 35. The exhaust gas flow path 37 flows downward. The exhaust gas passage 37 communicates with an exhaust hole 40 provided at the bottom of the storage container 18. A heat insulating member 33 is also provided on the exhaust gas inner wall 35 on the cell stack 5 side.

  Thereby, the exhaust gas generated by the operation of the module 4 flows through the exhaust gas passage 37 and is then exhausted from the exhaust hole 40. The exhaust hole 40 may be formed by cutting out a part of the bottom of the storage container 18 or may be formed by providing a tubular member. Further, a purification device (for example, a honeycomb-like combustion catalyst or the like) for purifying exhaust gas discharged from the module 4 can be provided in the exhaust hole 40.

  Although not shown, in the module 4, an ignition device for igniting the fuel gas that has passed through the fuel battery cell 19 is positioned between the fuel battery cell 19 and the reformer 3. It is preferably inserted from the side surface of the storage container 2. In addition, by igniting the fuel gas that has passed through the fuel cell 19 by the ignition device, the temperature in the module 4 can be increased, and the temperature of the fuel cell 19 and the reformer 3 is maintained at a high temperature. be able to.

By the way, in the fuel cell device described above, the pure water generated in the water treatment device 9 is stored in the water tank 11, and the water stored in the water tank 11 is supplied to the reformer 3 by the water pump 12. However, bubbles are generated in the condensed water supply pipe 10 that connects the water treatment apparatus 9 and the water tank 11 (hereinafter, the condensed water supply pipe 10 that connects the water treatment apparatus 9 and the water tank 11 is referred to as a connection pipe). In some cases, the flow of water supplied from the water treatment device 9 is blocked by the bubbles, the water level of the water tank 11 is lowered, and in some cases, the operation of the fuel cell device may be stopped.

  Therefore, the fuel cell device of the present embodiment has a water flow changing member that changes the water flow of the water flowing through the connection pipe. Thereby, even when bubbles are included in the water supplied from the water treatment device 11, by changing the water flow of the water flowing through the connection pipe, it is possible to suppress the water flowing through the connection pipe from being blocked, A fuel cell device with improved long-term reliability can be obtained. Below, the example of a water flow change member is demonstrated using drawing.

  FIG. 4 is a conceptual diagram showing a water treatment device, a water tank, and a connection pipe connecting the water treatment device and the water tank constituting the fuel cell device of the present embodiment, and a water flow change that is a rotating body in the connection pipe It is a conceptual diagram which shows the example which provided the member.

  In FIG. 4, a water flow changing member 42 (hereinafter referred to as a rotating body 42) that is a rotating body such as a fan or a propeller is provided inside the connection pipe 41. In addition, although the connection piping 41 has shown the example provided so that the upper end sides of the water treatment apparatus 9 and the water tank 11 may be connected, it is not restricted to this.

  When bubbles are contained in the water supplied from the water treatment device 9, the bubbles flow to the water tank 11 through the connection pipe 41, and then the excess water stored in the water tank 11 provided in the water tank 11. Is discharged through the drain pipe 43 for discharging (overflow), but when some of the bubbles remain in the connection pipe 41, the flow of water supplied from the water treatment device 9 is blocked, and the water tank Accordingly, the water level of the fuel cell device 11 may be lowered, and in some cases, the operation of the fuel cell device may be stopped.

  Here, in FIG. 4, since the rotating body 42 is provided inside the connection pipe 41, the water flow through the connection pipe 41 can be changed by operating the rotating body 42. Thereby, even if bubbles flow in the connection pipe 41, the bubbles can flow to the water tank 11, and the bubbles can be prevented from staying in the connection pipe 41. Thereby, it can suppress that the water supplied from the water treatment apparatus 9 which flows through the connection piping 41 is interrupted | blocked. Therefore, it is possible to suppress a drop in the water level of the water tank 11 and to obtain a fuel cell device with improved long-term reliability.

  4 shows an example in which the rotating body 42 is provided in the connection pipe 41. However, if the water flow through the connection pipe 41 can be changed, the rotary body 42 is not necessarily provided in the connection pipe 41. For example, it may be provided on the inlet side or the outlet side of the connection pipe 41 in the water treatment device 9, but when changing the water flow of water flowing through the connection pipe 41 more efficiently, the rotating body 42 is connected. It is preferable to provide inside the pipe 41.

  In addition, it is preferable that the upper end of the connection pipe 41 is connected to be lower than the lower end of the drain pipe 43 (in FIG. 4, the position of the lower end of the drain pipe 43 is indicated by a broken line, The same applies to the figure.) Thereby, since the air bubbles flowing from the connection pipe 41 to the water tank 11 can be efficiently flowed to the drain pipe 43 side, the air bubbles flowing into the water tank 11 can be efficiently discharged to the outside.

  FIG. 5 is a conceptual diagram showing a water treatment device, a water tank, and a connection pipe connecting the water treatment device and the water tank constituting the fuel cell device of the present embodiment. The connection pipe is vibrated with vibration. It is a conceptual diagram which shows the example which provided the vibrating body to give.

A connecting body 41 shown in FIG. 5 is provided with a vibrating body 44 that vibrates the connecting pipe 41. Accordingly, by operating the vibrating body 44, the water flow of the water flowing through the connection pipe 41 can be changed, the bubbles can be prevented from staying in the connection pipe 41, and the water supplied from the water treatment device 9 is blocked. Can be suppressed. Therefore, it is possible to suppress a drop in the water level of the water tank 11 and to obtain a fuel cell device with improved long-term reliability.

  In addition, for example, when bubbles are attached to the inner surface of the connection pipe 41, the bubbles attached to the inner surface of the connection pipe 41 can be removed by vibration by the vibrating body 44, and the bubbles are more efficiently removed. It can suppress staying in the connection piping 41.

  Such a vibrating body 44 is not particularly limited as long as it can give vibration to the connection pipe 41. For example, a motor, a piezoelectric vibrating body, a solenoid, and the like can be appropriately provided. In addition, since these vibrating bodies 44 should just be able to give the vibration to the connection piping 41, they do not necessarily need to be provided in the connection piping 41.

  FIG. 6 is a conceptual diagram showing a heat exchanger, a water treatment device, a water tank, and a connection pipe connecting the water treatment device and the water tank that constitute the fuel cell device of the present embodiment. It is a conceptual diagram which shows the example which provided the valve in the condensed water supply pipe | tube which connects a processing apparatus.

  In the fuel cell device of the present embodiment shown in FIGS. 4 and 5, the example in which the rotating body 42 and the vibrating body 44 are provided as the water flow changing member in the connection pipe 41 is shown. The flow of water flowing in the connection pipe 41 may be changed. Therefore, for example, by changing the water pressure of the water flowing through the connection pipe 41, it is possible to suppress the bubbles from staying in the connection pipe 41.

  Therefore, in the fuel cell device of the present embodiment shown in FIG. 6, the water pressure of the condensed water supplied to the water treatment device 9 is adjusted to the condensed water supply pipe 10 that connects the heat exchanger 8 and the water treatment device 9. The example which provided the valve 45 (for example, electromagnetic valve etc.) which is a water pressure adjustment member for this is shown.

  Thereby, when the amount of the condensed water supplied to the water treatment device 9 becomes a constant amount, the water pressure of the condensed water supplied to the water treatment device 9 is controlled by releasing the valve 45. As a result, the water pressure of the water flowing through the connection pipe 41 can be increased. That is, in this embodiment, since the water flow of the water flowing through the connection pipe 41 can be changed by changing the water pressure of the water flowing through the connection pipe 41, the valve 45 (water pressure adjusting member) is used as the water flow changing member. Plays the function. Thereby, it can suppress that a bubble stays in the connection piping 41, and can suppress that the water supplied from the water treatment apparatus 9 is interrupted | blocked. Therefore, it is possible to suppress a drop in the water level of the water tank 11 and to obtain a fuel cell device with improved long-term reliability.

  In addition, in the example shown in FIG. 6, when changing the water pressure of the water which flows through the connection piping 41, the example which provided the valve 45 in the condensed water supply pipe | tube 10 which connects the heat exchanger 8 and the water treatment apparatus 9 was shown. However, if the water pressure of the water flowing through the connection pipe 41 can be changed, for example, it can be provided directly at the heat exchanger 8 or at the inlet portion of the connection pipe 41.

  By the way, although the water flow changing member described above can be operated at all times by starting the operation of the fuel cell device, it may be determined that bubbles are not generated in the connection pipe 41 in that case. If the system is always operated, the overall efficiency may be reduced. Therefore, by operating the water flow changing member only when a predetermined condition is satisfied, it is possible to obtain a fuel cell device with improved long-term reliability while suppressing a decrease in overall efficiency.

  7 is a conceptual diagram showing an example in which a water level detection member is provided in the water tank 11 shown in FIG. 4, and FIG. 8 is a flowchart showing an example of an operation method of the fuel cell device shown in FIG.

  The water tank 11 shown in FIG. 7 is provided with a float switch 46 that is a water level detection member that detects the water level of the water tank 11.

  When the water level of the water tank 11 is high, the bubbles flowing into the connection pipe 41 described above remain in the connection pipe 41, and even if the water supply from the water treatment device 9 is blocked, the water tank 11 is sufficient. Since there is a water level, water cannot be supplied to the reformer 3, but when the water level of the water tank 11 is low, bubbles remain in the connection pipe 41 and are supplied from the water treatment device 9. When the water is blocked, the water level in the water tank 11 decreases, and there is a risk that the water supplied to the reformer 3 will eventually run short and the operation of the fuel cell device will stop. Therefore, the water tank 11 is preferably provided with a water level detection member that can detect the water level of the water tank 11.

  Therefore, in the fuel cell device shown in FIG. 7, the water tank 11 is provided with a float switch 46 that is a water level detection member that detects the water level of the water tank 11, and accordingly, according to the water level of the water tank 11. An efficient operation can be performed by appropriately operating the water flow changing member.

  Here, the float switch 46 shown in FIG. 7 is turned on when the water level of the water tank 11 is equal to or higher than a predetermined water level (L1), and when the water level is lower than the predetermined water level (L1). The switch is turned off. FIG. 7 shows a state where the switch is ON.

  Hereinafter, the operation of the fuel cell device of the present embodiment will be described with reference to FIG. In addition, the information of ON / OFF of a float switch is transmitted to the control apparatus 7, and the control apparatus 7 controls operation | movement of a water flow change member based on the information. Therefore, the control device 7 includes a microcomputer and includes an input / output interface, a CPU, a RAM, and a ROM. The CPU performs the operation of the fuel cell device, the RAM temporarily stores variables necessary for executing the program, and the ROM stores the program.

  In the control shown in FIG. 8, the control device 7 first determines in step S1 whether or not the water level of the water tank 11 is equal to or lower than a predetermined water level (L1) set in advance. When the water level in the water tank 11 exceeds (is higher than) the predetermined water level (L1), the process proceeds to step S2 and the water flow changing member is not operated. The predetermined water level (L1) can be set as appropriate, but can be set higher than the upper end of the connection portion between the water tank 11 and the connection pipe 41 for efficient operation.

  If it is determined in step S1 that the water level in the water tank 11 is equal to or lower than the predetermined water level (L1), the process proceeds to step S3, and it is determined whether or not the predetermined water level (L1) or lower is continued for a predetermined time. When the water level of the water tank 11 is equal to or lower than the predetermined water level (L1), depending on the amount of water supplied from the water treatment device 9, it is assumed that the water level immediately rises. If the water flow changing member is operated, the efficiency may decrease. Therefore, in step S3, it is determined whether or not a predetermined water level (L1) or lower is continued for a predetermined time. In addition, although it can set suitably based on the magnitude | size etc. of the water tank 11 with predetermined time, it can be set as about 1 to 30 minutes, for example.

Here, when the water level of the water tank 11 is equal to or lower than the predetermined water level (L1) and the predetermined time has not elapsed, it is continuously detected whether or not the predetermined time has elapsed without operating the water flow changing member. To do. On the other hand, when the water level of the water tank 11 is equal to or lower than the predetermined water level (L1) and a predetermined time has elapsed, the process proceeds to step S4 and the water flow changing member is operated. Thereby, even if bubbles flow in the connection pipe 41, the bubbles can flow to the water tank 11, and the bubbles can be prevented from staying in the connection pipe 41. Therefore, the water supplied from the water treatment device 9 flowing through the connection pipe 41 can be prevented from being blocked.

  After operating the water flow changing member, the process proceeds to step S5, where it is detected whether or not the water level of the water tank 11 has exceeded a predetermined water level (L1). When the water level of the water tank 11 does not exceed the predetermined water level (L1), the operation of the water flow changing member is continued.

  On the other hand, when the water level of the water tank 11 exceeds the predetermined water level (L1), the water level of the water tank 11 becomes sufficient, bubbles remain in the connection pipe 41, and the supply of water from the water treatment device 9 is blocked. Even if it is, water can be supplied to the reformer 3. Therefore, from the viewpoint of suppressing a decrease in overall efficiency, the process proceeds to step S6, and control is performed to stop the operation of the water flow changing member.

  An efficient operation can be performed by the control device 7 performing the above control.

  Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and improvements can be made without departing from the scope of the present invention. It is.

  For example, water in the water treatment device 9 can be efficiently supplied to the water tank 11 (bubbles flow efficiently to the water tank 11 side), and the connection pipe 41 is connected to the water so that the bubbles efficiently flow to the water tank 11 side. It is also possible to connect by inclining so that the upper end on the tank 11 side is higher than the upper end on the water treatment device 9 side. In this case, it is preferable to connect so that the inclination angle is, for example, 10 ° or more.

  Further, when the water level detection member that detects the water level of the water tank 11 is one that can measure the water level at two locations (upper limit water level and lower limit water level), whether or not the predetermined water level has been exceeded in the above-described flowchart. What is necessary is just to read a part as whether the upper limit water level was detected.

  Furthermore, when the water level of the water tank 11 exceeds a predetermined water level (L1), it is preferable to stop the operation of the water flow changing member. However, in this case as well, the water level of the water tank 11 is the predetermined water level (L1). After a predetermined time has elapsed (for example, 1 to 30 minutes), the operation of the water flow changing member may be stopped.

3: Reformer 9: Water treatment device 11: Water tank 19: Fuel cell 41: Connection pipe 42: Rotating body (water flow changing member)
43: Drain pipe 44: Vibrating body (water flow changing member)
45: Water pressure changing member (water flow changing member)
46: Float switch (water level detection member)

Claims (4)

A fuel battery cell that generates power with a fuel gas and an oxygen-containing gas;
A reformer capable of a steam reforming reaction for generating fuel gas to be supplied to the fuel cell, a water treatment device for purifying water to be supplied to the reformer, and
A water tank for storing the water treated by the water treatment device and supplied to the reformer;
A connection pipe connecting the water treatment device and the water tank;
A water flow changing member that is provided in or on the connection pipe and changes the flow of water flowing through the connection pipe;
In the water tank, provided with a water level detection member for detecting the water level in the water tank, when the water level in the water tank detected by the water level detection member is equal to or lower than a predetermined first water level, A control device for operating the water flow changing member;
A fuel cell device comprising: 2. The fuel according to claim 1, wherein the control device performs control to stop the operation of the water flow changing member when the water level detected by the water level detecting member exceeds the first water level. Battery device. The fuel cell system according to claim 1 or claim 2, wherein the water flow changing member is a rotating body. The water flow changing member is a fuel cell system according to claim 1 or claim 2, characterized in that a vibrator for vibrating the connecting pipe.

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