JP2013049906A - Water electrolysis system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water electrolysis system capable of reducing power consumption to the extent practicable, of improving economy and convenience, and of enhancing system efficiency.SOLUTION: The water electrolysis system 10 includes a high-pressure hydrogen production device 12 that electrolyzes water to generate oxygen and high-pressure hydrogen having a higher pressure than the oxygen, a gas-liquid separation device 22 that separates moisture contained in the high-pressure hydrogen and is attached to a hydrogen pipeline 20 for discharging the high-pressure hydrogen from the high-pressure hydrogen production device 12, a high-pressure hydrogen supply pipeline 24 for discharging the high-pressure hydrogen devoid of moisture from the gas-liquid separation device 22, a cooling device 26 that is attached to the high-pressure hydrogen supply pipeline 24 and can variably control the temperature of the high-pressure hydrogen to control the humidity thereof, and a controller 28.

Description

  The present invention relates to a high-pressure hydrogen production apparatus that electrolyzes water to generate oxygen on the anode side and high-pressure hydrogen that is higher than oxygen on the cathode side, and a hydrogen pipe that discharges the high-pressure hydrogen from the high-pressure hydrogen production apparatus A water electrolysis system comprising: a gas-liquid separator that separates water contained in the high-pressure hydrogen; and a high-pressure hydrogen supply pipe that extracts the high-pressure hydrogen from which water has been separated from the gas-liquid separator. .

  Generally, hydrogen is used as a fuel gas used for a power generation reaction of a fuel cell. This hydrogen is produced by, for example, a water electrolysis device. The water electrolysis apparatus uses a solid polymer electrolyte membrane (ion exchange membrane) in order to decompose water and generate hydrogen (and oxygen). Electrode catalyst layers are provided on both sides of the solid polymer electrolyte membrane to form an electrolyte membrane / electrode structure, and power supply bodies are disposed on both sides of the electrolyte membrane / electrode structure to provide unit cells. Is configured.

  Therefore, a cell unit in which a plurality of unit cells are stacked is supplied with voltage at both ends in the stacking direction, and water is supplied to the anode-side power feeding body. For this reason, water is decomposed and hydrogen ions (protons) are generated on the anode side of the electrolyte membrane / electrode structure, and the hydrogen ions permeate the solid polymer electrolyte membrane and move to the cathode side to bond with electrons. Thus, hydrogen is produced. On the other hand, on the anode side, oxygen generated together with hydrogen is discharged from the cell unit together with excess water.

  In the above water electrolysis apparatus, hydrogen containing water is produced. For example, when supplying product hydrogen to a fuel cell vehicle or the like, a desired dry state (water concentration), for example, hydrogen having a water content of 5 ppm or less (hereinafter also referred to as dry hydrogen) is required.

  For this reason, for example, the dehumidifying mechanism disclosed in Patent Document 1 includes a dehumidifying device in which a dehumidifying agent that dehumidifies non-processed gas is housed in a container body, and allows the cooling gas to flow through the container body. A cooling trace is provided.

  The regeneration process of the dehumidifying device includes a heating process for removing moisture by heating the dehumidifying agent and a cooling process for cooling the heated dehumidifying agent to about room temperature. Specifically, in the heating step, the entire container body is heated by heating wires that are also arranged at substantially equal intervals in the spiral gap of the cooling trace in the container body. Further, in the cooling process, the cooling gas is conducted to the cooling trace and is cooled until the dehumidifying agent recovers the predetermined dehumidifying performance.

  Further, as the dehumidifier, a pressure fluctuation adsorption method (PSA) or the like that removes moisture contained in hydrogen gas by using a pressure difference between the adsorption pressure and the desorption pressure in the adsorption cylinder is adopted.

  Furthermore, as a simple type dehumidifier, an apparatus in which an adsorbent such as zeolite is exchanged is used.

JP 2004-149890 A

  However, in Patent Document 1 described above, since the regeneration process includes a heating process and a cooling process, there is a concern that the entire process may be prolonged due to a temperature change. In addition, there is a problem that the system efficiency is lowered from the viewpoint of the amount of power supplied to the heating wire.

  Moreover, in said PSA type dehumidifier, it is necessary to comprise a high pressure adsorption cylinder and a high pressure device. Therefore, the entire system is complicated, and there are problems in cost and durability.

  Furthermore, in a dehumidifying apparatus that uses an exchangeable adsorbent, the adsorbent replacement time is advanced depending on the moisture concentration. Accordingly, there is a problem that replacement maintenance is frequently required and convenience is lowered. In addition, in order to suppress the replacement frequency, a large amount of adsorbent is required, and there is a problem that the entire system is enlarged.

  The present invention solves this type of problem, and can reduce power consumption as much as possible, improve economic efficiency and convenience, and can improve system efficiency. The purpose is to provide a system.

  The present invention relates to a high-pressure hydrogen production apparatus that electrolyzes water to generate oxygen on the anode side and high-pressure hydrogen that is higher than oxygen on the cathode side, and a hydrogen pipe that discharges the high-pressure hydrogen from the high-pressure hydrogen production apparatus A water electrolysis system comprising: a gas-liquid separator that separates water contained in the high-pressure hydrogen; and a high-pressure hydrogen supply pipe that extracts the high-pressure hydrogen from which water has been separated from the gas-liquid separator. Is.

  In this water electrolysis system, the high-pressure hydrogen supply pipe is provided with a cooling device that variably controls the temperature of the high-pressure hydrogen in order to adjust the humidity of the high-pressure hydrogen.

  In this water electrolysis system, the cooling device includes a Peltier element, the water electrolysis system includes a control unit, and the control unit detects pressure on the cathode side in the high-pressure hydrogen production apparatus. And current varying means for varying a current value applied to the Peltier element based on the detected pressure.

  Further, in this water electrolysis system, the cooling device includes a heat exchanger, the water electrolysis system includes a control unit, and the control unit detects the pressure on the cathode side in the high-pressure hydrogen production apparatus. It is preferable to include means for changing the amount of refrigerant to be circulated through the heat exchanger based on the detected pressure.

  Furthermore, in this water electrolysis system, the cooling device includes a Peltier element and a heat exchanger, the water electrolysis system includes a control unit, and the control unit controls the pressure on the cathode side in the high-pressure hydrogen production apparatus. Pressure detecting means for detecting, current varying means for varying a current value applied to the Peltier element based on the detected pressure, and circulating in the heat exchanger based on the detected pressure It is preferable to provide a refrigerant body amount varying means for varying the refrigerant body amount.

  Further, in this water electrolysis system, the cooling device includes a Peltier element, the water electrolysis system includes a control unit, and the control unit detects current value of an electrolysis current of the high-pressure hydrogen production device, It is preferable to include a current varying unit that varies a current value applied to the Peltier element based on the detected electrolytic current value.

  Further, in this water electrolysis system, the cooling device includes a heat exchanger, the water electrolysis system includes a control unit, and the control unit includes a current detection unit that detects an electrolysis current value of the high-pressure hydrogen production device. Preferably, the refrigerant body variable means for varying the amount of the refrigerant flowing through the heat exchanger based on the detected electrolysis current value is provided.

  Furthermore, in this water electrolysis system, the cooling device includes a Peltier element and a heat exchanger, the water electrolysis system includes a control unit, and the control unit detects an electrolysis current value of the high-pressure hydrogen production device. Current detection means, current variable means for varying the current value applied to the Peltier element based on the detected electrolytic current value, and the heat exchanger based on the detected electrolytic current value It is preferable to provide a refrigerant body amount varying means for varying the amount of refrigerant body to be circulated.

  Moreover, in this water electrolysis system, it is preferable that a heat exchanger is disposed upstream of the Peltier element.

  According to the present invention, the temperature of the high-pressure hydrogen can be variably controlled, so that the high-pressure hydrogen can be dehumidified efficiently and reliably. In addition, it is possible to improve economy and convenience without wasting power. Thereby, it is possible to easily improve the system efficiency with a simple and economical configuration.

It is a schematic structure explanatory view of a water electrolysis system concerning a 1st embodiment of the present invention. It is a flowchart explaining operation | movement of the said water electrolysis system. It is a map figure which shows the relationship between a pressure, the amount of cooling water, and Peltier power consumption. It is a relation explanatory view of pressure and moisture concentration. It is a relationship explanatory drawing of temperature and moisture concentration. It is a schematic structure explanatory drawing of the water electrolysis system concerning a 2nd embodiment of the present invention. It is a flowchart explaining operation | movement of the said water electrolysis system. It is a map figure which shows the relationship between an electrolysis electric current value, the amount of cooling water, and Peltier power consumption. It is schematic structure explanatory drawing of the water electrolysis system which concerns on the 3rd Embodiment of this invention. It is a flowchart explaining operation | movement of the said water electrolysis system. It is schematic structure explanatory drawing of the water electrolysis system which concerns on the 4th Embodiment of this invention. It is a flowchart explaining operation | movement of the said water electrolysis system. It is schematic structure explanatory drawing of the water electrolysis system which concerns on the 5th Embodiment of this invention. It is a flowchart explaining operation | movement of the said water electrolysis system. It is schematic structure explanatory drawing of the water electrolysis system which concerns on the 6th Embodiment of this invention. It is a flowchart explaining operation | movement of the said water electrolysis system.

  As shown in FIG. 1, the water electrolysis system 10 according to the first embodiment of the present invention electrolyzes water (pure water) to generate oxygen and high-pressure hydrogen (higher than the atmospheric oxygen pressure, For example, a high-pressure hydrogen production apparatus (differential pressure water electrolysis apparatus) 12 that produces 1 MPa to 70 MPa hydrogen) is separated from the oxygen discharged from the high-pressure hydrogen production apparatus 12 and excess water, and the water is stored. A water storage device 14, a water circulation device 16 that circulates the water stored in the water storage device 14 to the high-pressure hydrogen production device 12, and pure water generated from city water is supplied to the water storage device 14. A water supply device 18, a gas-liquid separation device 22 for removing water contained in the high-pressure hydrogen led out from the high-pressure hydrogen production device 12 to the hydrogen pipe 20, and the high-pressure hydrogen from which water has been separated Separation device 2 A high-pressure hydrogen supply pipe 24 led out from the above, a cooling device 26 which is arranged in the high-pressure hydrogen supply pipe 24 and variably controls the temperature of the high-pressure hydrogen in order to adjust the humidity of the high-pressure hydrogen, and control of the entire system And a control unit (ECU) 28.

  The high-pressure hydrogen production apparatus 12 includes a cell unit in which a plurality of unit cells 30 are stacked. At one end in the stacking direction of the unit cells 30, a terminal plate 32a, an insulating plate 34a, and an end plate 36a are sequentially arranged outward. Similarly, a terminal plate 32b, an insulating plate 34b, and an end plate 36b are sequentially disposed on the other end in the stacking direction of the unit cells 30 toward the outside. The end plates 36a and 36b are integrally clamped and held.

  Terminal portions 38a and 38b are provided on the side portions of the terminal plates 32a and 32b so as to protrude outward. The terminal portions 38a and 38b are electrically connected to the electrolytic power source 40 via the wirings 39a and 39b.

  The unit cell 30 includes, for example, a disk-shaped electrolyte membrane / electrode structure 42, and an anode side separator 44 and a cathode side separator 46 that sandwich the electrolyte membrane / electrode structure 42. The anode side separator 44 and the cathode side separator 46 have a disk shape.

  The electrolyte membrane / electrode structure 42 includes, for example, a solid polymer electrolyte membrane 48 in which a perfluorosulfonic acid thin film is impregnated with water, and an anode-side power feeder 50 and a cathode provided on both surfaces of the solid polymer electrolyte membrane 48. Side power supply body 52.

  An anode electrode catalyst layer 50 a and a cathode electrode catalyst layer 52 a are formed on both surfaces of the solid polymer electrolyte membrane 48. The anode electrode catalyst layer 50a uses, for example, a Ru (ruthenium) -based catalyst, while the cathode electrode catalyst layer 52a uses, for example, a platinum catalyst.

  A water supply communication hole 56 for supplying water (pure water) to each other in the stacking direction, and oxygen generated by the reaction and unreacted water are discharged to the outer peripheral edge of the unit cell 30. The discharge communication hole 58 and the hydrogen communication hole 60 for flowing hydrogen generated by the reaction are provided.

  A surface of the anode separator 44 facing the electrolyte membrane / electrode structure 42 is provided with a first flow path 64 communicating with the water supply communication hole 56 and the discharge communication hole 58. The first flow path 64 is provided within a range corresponding to the surface area of the anode-side power supply body 50 and is configured by a plurality of flow path grooves, a plurality of embosses, and the like. In the first flow path 64, oxygen generated by the reaction and unreacted water flow.

  A second flow path 68 communicating with the hydrogen communication hole 60 is formed on the surface of the cathode separator 46 facing the electrolyte membrane / electrode structure 42. The second flow path 68 is provided in a range corresponding to the surface area of the cathode-side power feeder 52, and includes a plurality of flow path grooves, a plurality of embosses, and the like. High-pressure hydrogen generated by the reaction flows through the second flow path 68.

  The water circulation device 16 includes a circulation pipe 72 that communicates with the water supply communication hole 56 of the high-pressure hydrogen production apparatus 12. The circulation pipe 72 includes a circulation pump 74 and an ion exchanger 76 to form the water storage device 14. It is connected to the bottom of the tank part 78.

  One end portion of the return pipe 80 communicates with the upper portion of the tank portion 78, and the other end of the return pipe 80 communicates with the discharge communication hole 58 of the high-pressure hydrogen production apparatus 12. One end of the return pipe 80 is set to a position that always opens in the water stored in the tank portion 78.

  A pure water supply pipe 84 connected to the water supply device 18 and an oxygen exhaust pipe 86 for discharging oxygen separated from the pure water in the tank section 78 are connected to the tank section 78.

  One end of the hydrogen pipe 20 is connected to the hydrogen communication hole 60 of the high-pressure hydrogen production apparatus 12, and the other end of the hydrogen pipe 20 is connected to the gas-liquid separator 22. The gas-liquid separator 22 includes a tank unit 88 for storing water. A drain line 90 is connected to the lower portion of the tank portion 88, and a drain valve 92 is disposed in the drain line 90.

  The high-pressure hydrogen from which moisture has been removed by the gas-liquid separator 22 is led out to the high-pressure hydrogen supply pipe 24 as dry hydrogen. The high-pressure hydrogen supply pipe 24 is provided with a cooling device 26, and the cooling device 26 includes a Peltier dehumidifier (Peltier element) 94 and a heat exchanger 96.

  The Peltier dehumidifier 94 is configured by a cooler using a Peltier element, and includes a variable power source 97. The Peltier dehumidifier 94 is connected to a refrigerant pipe 98 for releasing heat on the high temperature side. Instead of the refrigerant pipe 98, heat radiating fins or the like may be used.

  The heat exchanger 96 is arranged in series upstream of the Peltier dehumidifier 94. The heat exchanger 96 is connected to a cooling water supply pipe 100 to which cooling water is supplied as a refrigerant body and a cooling water discharge pipe 102 from which the cooling water is discharged. The cooling water supply pipe 100 is provided with a flow rate adjustment valve 104 for making the amount of cooling water flowing through the heat exchanger 96 variable.

  The cooling water discharge pipe 102 may be connected to the inlet side of the refrigerant pipe 98, and water used for electrolysis may be circulated through the cooling water supply pipe 100. This eliminates the need for a new water supply source and provides the effect of simplifying the entire system. Further, the cooling water discharge pipe 102 and the refrigerant pipe 98 may be configured separately, and it is possible to supply electrolysis water only to either the heat exchanger 96 or the Peltier dehumidifier 94. is there.

  The control unit 28 includes a pressure detection unit 110 that detects the pressure on the cathode side in the high-pressure hydrogen production apparatus 12, and a current variable that varies the current value applied to the Peltier dehumidifier 94 based on the detected pressure. Means 112 and cooling water amount varying means (refrigerant amount varying means) 114 for varying the amount of cooling water to be circulated to the heat exchanger 96 based on the detected pressure.

  The hydrogen pipe 20 is provided with a pressure sensor 116 for measuring the pressure on the cathode side in the high-pressure hydrogen production apparatus 12. A detection signal from the pressure sensor 116 is sent to the pressure detection means 110.

  A condenser 118 and a back pressure valve 120 are arranged in the high pressure hydrogen supply pipe 24 on the downstream side of the cooling device 26. The condenser 118 is composed of a sintered filter and the like, and the back pressure valve 120 is opened at a predetermined set pressure (for example, 35 MPa) to supply high-pressure hydrogen as product hydrogen to a fuel cell vehicle (not shown). Can do.

  The operation of the water electrolysis system 10 configured as described above will be described below along the flowchart shown in FIG.

  First, as shown in FIG. 3, the relationship between the cathode-side pressure P of the high-pressure hydrogen production device 12, the power consumption W of the Peltier dehumidifier 94 and the cooling water amount Q of the heat exchanger 96 is created in advance as a map.

  Specifically, the hydrogen pressure (cathode side pressure) and the moisture concentration contained in hydrogen have the relationship shown in FIG. The moisture concentration in hydrogen decreases as the hydrogen pressure increases, that is, as the pressure increases, and the flow rate also decreases, so dehumidification is facilitated.

  On the other hand, as shown in FIG. 5, the water concentration in hydrogen decreases as the hydrogen temperature decreases, and the water temperature can be decreased by increasing the cooling temperature as the hydrogen pressure increases.

  As described above, as shown in FIG. 3, a control map is obtained from the relationship between the hydrogen pressure and the water concentration and the relationship between the hydrogen temperature and the hydrogen concentration.

  Therefore, electrolysis by the water electrolysis system 10 is started (step S1). As shown in FIG. 1, pure water generated from city water via the water supply device 18 is supplied to a tank unit 78 that constitutes the water storage device 14.

  In the water circulation device 16, the water in the tank unit 78 is supplied to the water supply communication hole 56 of the high-pressure hydrogen production device 12 through the circulation pipe 72 under the action of the circulation pump 74. On the other hand, a voltage (electrolytic current value A) is applied to the terminal portions 38a and 38b of the terminal plates 32a and 32b via the electrically connected electrolytic power source 40.

  Therefore, in each unit cell 30, water is supplied from the water supply communication hole 56 to the first flow path 64 of the anode side separator 44, and this water moves along the anode side power supply body 50. Therefore, water is decomposed by electricity in the anode electrode catalyst layer 50a, and hydrogen ions, electrons, and oxygen are generated. Hydrogen ions generated by the anodic reaction permeate the solid polymer electrolyte membrane 48 and move to the cathode electrode catalyst layer 52a side, and combine with electrons to obtain hydrogen (step S2).

  Thereby, hydrogen flows along the second flow path 68 formed between the cathode-side separator 46 and the cathode-side power feeder 52. This hydrogen is maintained at a higher pressure than the water supply communication hole 56, and can flow out of the high pressure hydrogen production apparatus 12 through the hydrogen communication hole 60.

  On the other hand, oxygen generated by the reaction and unreacted water flow through the first flow path 64, and these mixed fluids are discharged to the return pipe 80 of the water circulation device 16 along the discharge communication hole 58. The After the unreacted water and oxygen are introduced into the tank section 78 and separated, the water is introduced from the circulation pipe 72 through the ion exchanger 76 into the water supply communication hole 56 via the circulation pump 74. . Oxygen separated from the water is discharged to the outside from the oxygen exhaust pipe 86.

  The hydrogen generated in the high-pressure hydrogen production device 12 is sent to the gas-liquid separation device 22 through the hydrogen pipe 20. In the gas-liquid separator 22, water vapor (water) contained in hydrogen is separated from the hydrogen and stored in the tank unit 88, while the hydrogen is led out to the high-pressure hydrogen supply pipe 24.

  As described above, when water electrolysis is performed by the high-pressure hydrogen production apparatus 12 and hydrogen production is continued, the cathode-side pressure (hydrogen pressure) P increases to the set pressure of the back pressure valve 120. In the control unit 28, the pressure detection unit 110 detects the pressure P on the cathode side of the high-pressure hydrogen production apparatus 12 based on the detection signal from the pressure sensor 116 (step S3). In the pressure detection means 110, based on the detected pressure P, the amount of cooling water Q supplied to the heat exchanger 96 and the current value applied to the Peltier dehumidifier 94, that is, Peltier power consumption, from the map shown in FIG. W is calculated.

The cooling water amount varying means 114 controls the flow rate adjusting valve 104 to control the cooling water amount Q _map supplied from the cooling water supply pipe 100 to the heat exchanger 96 based on the map (step S4). For this reason, the high-pressure hydrogen introduced into the heat exchanger 96 along the high-pressure hydrogen supply pipe 24 undergoes heat exchange with the cooling water, and is dehumidified to a desired hydrogen concentration (see FIG. 5). Until cooled.

The high pressure hydrogen is then sent to the Peltier dehumidifier 94. In this Peltier dehumidifier 94, the current value applied by the variable power source 97 is controlled by the current variable means 112 by the Peltier power consumption W _map ( _{map in} FIG. 3) (step S4). Accordingly, the high-pressure hydrogen is cooled to a hydrogen temperature corresponding to a predetermined moisture concentration by the Peltier dehumidifier 94, and dehumidified to a desired humidity to obtain dry hydrogen.

  The dry hydrogen flows through the condenser 118 and the back pressure valve 120, rises to a set pressure, and then is supplied to the fuel cell vehicle (not shown) as manufactured hydrogen under the opening action of the back pressure valve 120.

  Thereby, the high pressure hydrogen production apparatus 12 shifts to a steady operation (Step S5), and the electrolysis operation is stopped (Step S6), whereby the operation by the water electrolysis system 10 is terminated.

  In this case, in the first embodiment, the high-pressure hydrogen supply pipe 24 is provided with a cooling device 26 capable of variably controlling the temperature of the high-pressure hydrogen in order to adjust the humidity of the high-pressure hydrogen. For this reason, even when the pressure is increasing and the pressure changes, or even when the pressure of the high-pressure hydrogen supply pipe 24 decreases due to some factor, the minimum necessary cooling is performed according to the detected pressure. It can be carried out. Therefore, it is possible to improve the efficiency of the entire system without unnecessary cooling.

  In addition, power is not consumed wastefully and no replacement of the adsorbent is required, thereby improving economy and convenience. Accordingly, there is an effect that it is possible to easily improve the system efficiency of the entire water electrolysis system 10 with a simple and economical configuration.

Further, the cooling device 26 includes a Peltier dehumidifier 94 and a heat exchanger 96 disposed on the upstream side of the Peltier dehumidifier 94. Therefore, by detecting the pressure P on the cathode side of the high-pressure hydrogen production apparatus 12, the heat exchange cooling water amount Q _map and the Peltier power consumption W _map of the Peltier dehumidifier 94 are variably controlled based on the map shown in FIG. be able to.

  As a result, high-pressure hydrogen can be controlled by the minimum amount of cooling water and power consumption that can be dehumidified to a desired moisture concentration, and the system efficiency can be greatly improved. It is done.

  Moreover, a heat exchanger 96 is disposed on the upstream side of the Peltier dehumidifier 94. For this reason, after the water in the high-pressure hydrogen is substantially removed by the heat exchanger 96, the high-pressure hydrogen is sent to the Peltier dehumidifier 94. Accordingly, it is possible to satisfactorily suppress the power consumption in the Peltier dehumidifier 94.

  FIG. 6 is an explanatory diagram of a schematic configuration of a water electrolysis system 130 according to the second embodiment of the present invention. In addition, the same reference number is attached | subjected to the component same as the water electrolysis system 10 which concerns on 1st Embodiment, and the detailed description is abbreviate | omitted. Similarly, in the third and subsequent embodiments described below, detailed description thereof is omitted.

  The water electrolysis system 130 includes a control unit 132, and the control unit 132 includes a current detection unit 134 that detects an electrolysis current value A of the high-pressure hydrogen production apparatus 12. In the high-pressure hydrogen production apparatus 12, a current detection sensor 136 for detecting an electrolysis current value is attached to the electrolysis power supply 40.

  The operation of the water electrolysis system 130 configured as described above will be described below along the flowchart shown in FIG.

  In the second embodiment, when the pressure P on the cathode side of the high-pressure hydrogen production apparatus 12 is constant, the relationship between the electrolysis current value A, the cooling water amount Q, and the Peltier power consumption W is as a map shown in FIG. Created in advance.

  That is, by changing the electrolysis current value A, the amount of hydrogen produced can be varied. For this reason, as the electrolysis current value A increases, the hydrogen production amount increases, and accordingly, the cooling water amount Q and the Peltier power consumption W are increased.

  Therefore, in the water electrolysis system 130, water electrolysis processing by the high-pressure hydrogen production apparatus 12 is started (step S11), and water electrolysis is performed at the electrolysis current value A (step S12). The pressure detection means 110 detects the pressure P on the cathode side of the high-pressure hydrogen production apparatus 12. If it is determined that the detected pressure P is constant (YES in step S13), the process proceeds to step S14.

In step S <b> 14, the electrolytic current value A is detected by the current detection unit 134 via the current detection sensor 136 attached to the electrolytic power supply 40. Therefore, as shown in FIG. 8, control is performed according to the cooling water amount Q _map of the heat exchanger 96 and the Peltier power consumption W _map of the Peltier dehumidifier 94 corresponding to the detected electrolysis current value A (step S15). Furthermore, after the water electrolysis system 130 shifts to a steady operation (step S16), the electrolysis process is stopped (step S17).

  In this case, in the second embodiment, when the pressure P of the high-pressure hydrogen is kept constant, the dehumidification treatment corresponding to the high-pressure hydrogen whose production amount varies with the change in the electrolysis current value A is minimized. The cooling water amount Q and the minimum Peltier power consumption W are controlled. Thereby, the effect similar to said 1st Embodiment is acquired, such as the system efficiency of the water electrolysis system 130 whole improving significantly.

  FIG. 9 is an explanatory diagram of a schematic configuration of a water electrolysis system 150 according to the third embodiment of the present invention.

  The water electrolysis system 150 includes a cooling device 152 and a control unit 154. The cooling device 152 includes only the Peltier dehumidifier 94, and the control unit 154 includes a pressure detection unit 110 and a current variable unit 112. In the water electrolysis system 150, the heat exchanger 96 and the cooling water amount varying means 114 are not used.

In the third embodiment, steps S21 to S26 are performed in accordance with the flowchart shown in FIG. At that time, the pressure P on the cathode side of the high-pressure hydrogen production device 12 is detected (step S23), and based on this pressure P, the Peltier power consumption W _map is read and the applied current of the Peltier dehumidifier 94 is controlled ( Step S24).

  As a result, in the third embodiment, the replacement of the adsorbent is not necessary, the maintainability is improved, and wasteful power consumption can be suppressed as much as possible. The same effect as the embodiment can be obtained.

  FIG. 11 is a schematic configuration explanatory view of a water electrolysis system 160 according to the fourth embodiment of the present invention.

  The water electrolysis system 160 includes a cooling device 162 and a control unit 164. The cooling device 162 includes only the heat exchanger 96, and the control unit 164 includes a pressure detection unit 110 and a cooling water amount varying unit 114. The water electrolysis system 160 does not use the Peltier dehumidifier 94 and the current varying means 112.

In the fourth embodiment, steps S31 to S36 are performed in accordance with the flowchart shown in FIG. At that time, based on the detected pressure P, the cooling water amount Q _map is read from the _map , and thereby the heat exchanger 96 is controlled (step S34).

  For this reason, in the fourth embodiment, it is not necessary to replace the adsorbent, the maintainability is improved, and wasteful power consumption can be suppressed as much as possible. The same effect as the embodiment can be obtained.

  FIG. 13 is an explanatory diagram of a schematic configuration of a water electrolysis system 170 according to the fifth embodiment of the present invention.

  The water electrolysis system 170 includes a cooling device 172 and a control unit 174. The cooling device 172 includes only the Peltier dehumidifier 94, and the control unit 174 does not use the cooling water amount varying unit 114.

In the water electrolysis system 170, the process of step S41-step S47 is performed along the flowchart shown in FIG. At that time, the Peltier power consumption W _map corresponding to the detected electrolysis current value A is read, and thereby the Peltier dehumidifier 94 is controlled (step S45).

  Therefore, in the fifth embodiment, the replacement of the dehumidifying agent is not necessary, the maintainability is improved, and wasteful power consumption can be suppressed as much as possible. The same effect as the form can be obtained.

  FIG. 15 is a schematic configuration explanatory view of a water electrolysis system 180 according to the sixth embodiment of the present invention.

  The water electrolysis system 180 includes a cooling device 182 and a control unit 184. The cooling device 182 includes only the heat exchanger 96, and the control unit 184 eliminates the current varying unit 112.

In the sixth embodiment, steps S51 to S57 are performed in accordance with the flowchart shown in FIG. At that time, based on the detected electrolysis current value A, the cooling water amount Q _map is read from the _map , and the heat exchanger 96 is controlled (step S55).

  Therefore, in the sixth embodiment, it is not necessary to replace the adsorbent, the maintainability is improved, and wasteful power consumption can be suppressed as much as possible. The same effect as the form can be obtained.

  In order to obtain dry hydrogen more reliably, an adsorber can be disposed downstream of the Peltier dehumidifier 94. At that time, since most of the water is removed by the Peltier dehumidifier 94, the frequency of replacement of the adsorbent can be significantly reduced as compared with the conventional configuration, and the entire system can be downsized.

DESCRIPTION OF SYMBOLS 10, 130, 150, 160, 170, 180 ... Water electrolysis system 12 ... High pressure hydrogen production device 14 ... Water storage device 16 ... Water circulation device 18 ... Water supply device 20 ... Hydrogen piping 22 ... Gas-liquid separation device 24 ... High pressure hydrogen supply Piping 26, 152, 162, 172, 182 ... Cooling devices 28, 132, 154, 164, 174, 184 ... Control unit 30 ... Unit cell 42 ... Electrolyte membrane / electrode structure 44 ... Anode side separator 46 ... Cathode side separator 48 ... Solid polymer electrolyte membrane 50 ... Anode-side power supply 52 ... Cathode-side power supply 56 ... Water supply communication hole 58 ... Discharge communication hole 60 ... Hydrogen communication holes 64, 68 ... Flow path 88 ... Tank section 94 ... Peltier dehumidifier 96 ... Heat exchanger 97 ... Variable power supply 100 ... Cooling water supply pipe 102 ... Cooling water discharge pipe 104 ... Flow rate adjustment valve 110 ... Pressure detection means 112 ... Electricity Flow varying means 114 ... cooling water amount varying means 116 ... pressure sensor 120 ... back pressure valve 134 ... current detection means 136 ... current detection sensor

Claims (8)

A high-pressure hydrogen production apparatus that electrolyzes water to generate oxygen on the anode side and high-pressure hydrogen higher than the oxygen on the cathode side;
A gas-liquid separation device that is disposed in a hydrogen pipe that discharges the high-pressure hydrogen from the high-pressure hydrogen production device and separates water contained in the high-pressure hydrogen;
A high-pressure hydrogen supply pipe for deriving the high-pressure hydrogen from which water has been separated from the gas-liquid separator;
A water electrolysis system comprising:
The water electrolysis system, wherein the high-pressure hydrogen supply pipe is provided with a cooling device that variably controls the temperature of the high-pressure hydrogen in order to adjust the humidity of the high-pressure hydrogen. The water electrolysis system according to claim 1, wherein the cooling device includes a Peltier element.
The water electrolysis system includes a control unit,
The control unit includes pressure detection means for detecting pressure on the cathode side in the high-pressure hydrogen production apparatus;
Current varying means for varying a current value applied to the Peltier element based on the detected pressure;
A water electrolysis system comprising: The water electrolysis system according to claim 1, wherein the cooling device includes a heat exchanger,
The water electrolysis system includes a control unit,
The control unit includes pressure detection means for detecting pressure on the cathode side in the high-pressure hydrogen production apparatus;
Refrigerant body amount varying means for varying the amount of refrigerant body to be circulated through the heat exchanger based on the detected pressure;
A water electrolysis system comprising: The water electrolysis system according to claim 1, wherein the cooling device includes a Peltier element and a heat exchanger,
The water electrolysis system includes a control unit,
The control unit includes pressure detection means for detecting pressure on the cathode side in the high-pressure hydrogen production apparatus;
Current varying means for varying a current value applied to the Peltier element based on the detected pressure;
Refrigerant body amount varying means for varying the amount of refrigerant body to be circulated through the heat exchanger based on the detected pressure;
A water electrolysis system comprising: The water electrolysis system according to claim 1, wherein the cooling device includes a Peltier element.
The water electrolysis system includes a control unit,
The control unit includes a current detection unit that detects an electrolytic current value of the high-pressure hydrogen production apparatus,
Current varying means for varying a current value applied to the Peltier element based on the detected electrolytic current value;
A water electrolysis system comprising: The water electrolysis system according to claim 1, wherein the cooling device includes a heat exchanger,
The water electrolysis system includes a control unit,
The control unit includes a current detection unit that detects an electrolytic current value of the high-pressure hydrogen production apparatus,
Based on the detected electrolysis current value, refrigerant body variable means for varying the amount of refrigerant flowing through the heat exchanger,
A water electrolysis system comprising: The water electrolysis system according to claim 1, wherein the cooling device includes a Peltier element and a heat exchanger,
The water electrolysis system includes a control unit,
The control unit includes a current detection unit that detects an electrolytic current value of the high-pressure hydrogen production apparatus,
Current varying means for varying a current value applied to the Peltier element based on the detected electrolytic current value;
Based on the detected electrolysis current value, refrigerant body variable means for varying the amount of refrigerant flowing through the heat exchanger,
A water electrolysis system comprising:   The water electrolysis system according to claim 4 or 7, wherein the heat exchanger is arranged upstream of the Peltier element.

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