Hydrogen isotope separation system

Abstract

This invention provides a hydrogen isotope separation system that can simplify the configuration of the heat transfer medium circuit. [Solution] The hydrogen isotope separation system 10 comprises an anode-side humidifier 14A, a separator 15, a coupler 17, a heat transfer medium circuit 30, and a control device 40. The heat transfer medium circuit 30 comprises a first flow passage 30A, a second flow passage 30B, a three-way valve 33, and a first temperature sensor 38A. The first flow passage 30A circulates the heat transfer medium to the coupler 17. The second flow passage 30B circulates the heat transfer medium to the anode-side humidifier 14A and the separator 15. The three-way valve 33 switches between connecting and disconnecting the first flow passage 30A and the second flow passage 30B. The first temperature sensor 38A detects the temperature of the heat transfer medium discharged from the coupler 17. The control device 40 connects the first flow passage 30A and the second flow passage 30B using the three-way valve 33 when the temperature T1 detected by the first temperature sensor 38A is above a predetermined temperature.

Description

Technical Field

[0001] The present invention relates to a hydrogen isotope separation system.

Background Art

[0002] In recent years, in order to enable more people to access affordable, reliable, sustainable and advanced energy, research and development on fuel cells that contribute to energy efficiency have been carried out. Conventionally, for example, a system is known in which raw water containing heavy water and tritium components is decomposed by a water electrolyzer to obtain hydrogen and oxygen each having a low content of deuterium and tritium (see, for example, Patent Document 1). This system extracts water (light water) with a low content of heavy water and tritium components by humidifying each of the hydrogen and oxygen obtained by the water electrolyzer and supplying them to a fuel cell.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] By the way, in the technology related to fuel cells, it is an issue to suppress the complication of the configuration of the heat medium circuit. For example, in the case of a system using a fuel cell for separating hydrogen isotopes as in the above conventional technology, temperature control of each of the electrolyzer, the humidifier and the fuel cell is required, and in a system that independently controls the temperature of each device, the configuration of the heat medium circuit may become complicated.

[0005] The present application aims to achieve simplification of the configuration of the heat medium circuit in order to solve the above problems. And by extension, it contributes to energy efficiency.

Means for Solving the Problems

[0006] In order to solve the above problems and achieve the above objectives, the present invention employs the following embodiments. (1): A hydrogen isotope separation system according to one aspect of the present invention (for example, hydrogen isotope separation systems 10, 10A in the embodiment) comprises a coupler that generates electricity using light hydrogen obtained from heavy water containing light water (for example, coupler 17 in the embodiment), a humidifier that humidifies the fluid supplied toward the coupler (for example, anode-side humidifier 14A in the embodiment), a heat transfer medium circuit (for example, heat transfer medium circuit 30 in the embodiment) that circulates a heat transfer medium that exchanges heat with the coupler and the humidifier, and a control device (for example, control device 40 in the embodiment) that controls the heat transfer medium circuit, wherein the heat transfer medium circuit comprises a first flow passage (for example, The control device comprises a first flow passage 30A in the embodiment, a second flow passage (for example, a second flow passage 30B in the embodiment) for circulating the heat transfer medium to the humidifier, a switching valve (for example, a three-way valve 33 in the embodiment) for switching the connection and disconnection of the first flow passage and the second flow passage, and a temperature sensor (for example, a first temperature sensor 38A in the embodiment) for detecting a temperature (for example, a first temperature T1 in the embodiment) related to the temperature of the heat transfer medium circulating in the first flow passage. The control device connects the first flow passage and the second flow passage using the switching valve when the temperature detected by the temperature sensor is equal to or greater than a predetermined temperature (for example, a first predetermined temperature T1b in the embodiment).

[0007] (2) In the hydrogen isotope separation system described in (1) above, the heat transfer medium circuit may include a humidification supply channel (for example, a seventh channel 30g in the embodiment) that supplies at least a portion of the heat transfer medium flowing through the second flow passage to the inside of the humidifier for humidification, and a supply switching valve (for example, a second on / off valve 36 in the embodiment) that switches the connection and disconnection of the second flow passage and the humidification supply channel.

[0008] (3) In the hydrogen isotope separation system described in (2) above, the heat transfer medium circuit includes a humidifier sensor (e.g., a water level sensor 39 in the embodiment) that detects a state quantity (e.g., a water level H in the embodiment) related to the amount of humidifying water stored inside the humidifier, and the control device may connect the second flow passage and the humidifying supply flow passage by the supply switching valve when the state quantity detected by the humidifier sensor is less than or equal to a predetermined value (e.g., a predetermined water level Ha in the embodiment).

[0009] (4) In the hydrogen isotope separation system described in any one of (1) to (3) above, the control device may reduce the power generation efficiency of the coupler when the temperature detected by the temperature sensor is below the predetermined temperature.

[0010] (5) In the hydrogen isotope separation system described in (4) above, the heat transfer medium circuit may include a heater (for example, heater 35 in the embodiment) that heats the heat transfer medium in the first flow passage.

[0011] (6) The hydrogen isotope separation system described in (4) above includes a condenser (for example, a first anode condenser 16A, a first cathode condenser 16B, a second anode condenser 18A, and a second cathode condenser 18B in the embodiment) provided for at least one of the fluids supplied to the coupler and the fluid discharged from the coupler, and the heat transfer medium circuit may include a condensate flow path (for example, a tenth flow path 30k in the embodiment) that supplies the condensate discharged from the condenser to the first flow path as the heat transfer medium.

[0012] (7) The hydrogen isotope separation system described in (6) above includes a separator (e.g., separator 15 in the embodiment) which is disposed between the humidifier and the coupler and separates hydrogen isotopes by having an ion exchange membrane (e.g., ion exchange membrane 15a in the embodiment) and a catalyst (e.g., an anode catalyst, a cathode catalyst in the embodiment), and the second flow passage may circulate the heat transfer medium to the humidifier and the separator.

[0013] (8): A hydrogen isotope separation system according to one aspect of the present invention (for example, hydrogen isotope separation systems 10, 10A in the embodiment) comprises a separator (for example, separator 15 in the embodiment) that separates hydrogen isotopes having an ion exchange membrane (for example, ion exchange membrane 15a in the embodiment) and a catalyst (for example, anode catalyst, cathode catalyst in the embodiment), a humidifier (for example, anode-side humidifier 14A in the embodiment) that humidifies the fluid supplied toward the separator, a heat transfer medium circuit (for example, heat transfer medium circuit 30 in the embodiment) that circulates a heat transfer medium that exchanges heat with the separator and the humidifier respectively, and a control device (for example, control device 40 in the embodiment) that controls the heat transfer medium circuit, wherein the heat transfer medium circuit is a heating device that heats the heat transfer medium. The control device comprises a device (for example, a heater 35 in the embodiment), a first flow passage (for example, a first flow passage 30A in the embodiment) for circulating the heat transfer medium to the heater, a second flow passage (for example, a second flow passage 30B in the embodiment) for circulating the heat transfer medium to the humidifier, a switching valve (for example, a three-way valve 33 in the embodiment) for switching the connection and disconnection of the first flow passage and the second flow passage, and a temperature sensor (for example, a first temperature sensor 38A in the embodiment) for detecting a temperature related to the temperature of the heat transfer medium circulating in the first flow passage. The control device connects the first flow passage and the second flow passage using the switching valve when the temperature detected by the temperature sensor is equal to or greater than a predetermined temperature (for example, a first predetermined temperature T1b in the embodiment). [Effects of the Invention]

[0014] According to (1) above, if the temperature detected by the temperature sensor is below a predetermined temperature, the first and second flow passages are blocked, allowing the temperature of the heat transfer medium in the first flow passage to rise rapidly. If the temperature detected by the temperature sensor is above the predetermined temperature, the first and second flow passages are connected, allowing the humidifier to be appropriately heated by the relatively high-temperature heat transfer medium. This allows for appropriate control of the temperatures of both the coupler and the humidifier while suppressing complexity in the configuration of the heat transfer medium circuit.

[0015] In the case of (2) above, the heat transfer medium in the heat transfer medium circuit can be used in conjunction with the water used for humidification in the humidifier, which can reduce the complexity of the system configuration by eliminating the need for dedicated equipment to supply water for humidification, for example.

[0016] In the case of (3) above, the switching of the supply switching valve is controlled according to the state quantity detected by the humidifier sensor, so that the amount of water stored inside the humidifier for humidification can be properly maintained.

[0017] In the case of (4) above, if the temperature detected by the temperature sensor is below a predetermined temperature, the temperature of the heat transfer medium in the first flow passage can be rapidly increased due to the increase in waste heat resulting from the decrease in the power generation efficiency of the coupler.

[0018] In the case of (5) above, by providing a heater, the temperature of the heat transfer medium in the first flow passage can be easily and quickly raised.

[0019] In the case of (6) above, the condensed water discharged from the condenser can be used as the heat transfer medium in the heat transfer medium circuit, which eliminates the need for dedicated equipment to supply the heat transfer medium and thus prevents the system configuration from becoming complicated.

[0020] In the case of (7) above, the warming up of the separator, which has a relatively higher operating temperature, can be prioritized over the heating of the humidifier. This prevents the dew point of the humidified inert gas supplied from the humidifier to the separator from becoming higher than the temperature of the separator, thereby suppressing a decrease in separation efficiency due to condensation occurring inside the separator, for example.

[0021] According to the above (8), when the temperature detected by the temperature sensor is less than the predetermined temperature, the first flow path and the second flow path are blocked, so that the temperature of the heat medium in the first flow path can be rapidly increased by the heater. When the temperature detected by the temperature sensor is greater than or equal to the predetermined temperature, the first flow path and the second flow path are connected, so that the humidifier can be appropriately heated by the relatively high-temperature heat medium. While suppressing the complication of the configuration of the heat medium circuit, the temperatures of the separator and the humidifier can be appropriately controlled.

Brief Description of the Drawings

[0022] [Figure 1] Configuration diagram of the hydrogen isotope separation system according to an embodiment of the present invention. [Figure 2] Diagram showing an example of an isotope exchange reaction in the separator of the hydrogen isotope separation system according to an embodiment of the present invention. [Figure 3] Configuration diagram of the heat medium circuit in the hydrogen isotope separation system according to an embodiment of the present invention. [Figure 4] Flowchart showing the operation at startup of the hydrogen isotope separation system according to an embodiment of the present invention. [Figure 5] Flowchart showing the operation after startup of the hydrogen isotope separation system according to an embodiment of the present invention. [Figure 6] Diagram showing an example of the correspondence relationship between the waste heat amount of the coupler, the rotation speed of the pump, the first temperature and the second temperature, the operation mode of the three-way valve, the water level of the humidifier, and the open / closed state of the second on-off valve in the hydrogen isotope separation system according to an embodiment of the present invention. [Figure 7] Configuration diagram of the heat medium circuit in the hydrogen isotope separation system according to a modified example of an embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0023] Hereinafter, the hydrogen isotope separation system according to an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 1 is a configuration diagram of a hydrogen isotope separation system 10 according to an embodiment. As shown in Figure 1, the hydrogen isotope separation system 10 of the embodiment includes, for example, an anode supply channel 10a and a cathode supply channel 10b, a cathode supply channel 10c for the separator, an anode discharge channel 10d and a cathode discharge channel 10e, a raw material tank 11, an electrolytic unit 12, a nitrogen tank 13, an anode-side humidifier 14A and a cathode-side humidifier 14B, a separator 15, a first anode-side condenser 16A and a first cathode-side condenser 16B, a coupler 17, a second anode-side condenser 18A and a second cathode-side condenser 18B, an anode-side on-off valve 19A and a cathode-side on-off valve 19B.

[0024] The raw material tank 11 stores water containing, for example, heavy water and light water. The raw material tank 11 is connected to the electrolytic heater 12. The raw material tank 11 supplies water containing heavy water and light water to the electrolytic heater 12. Note that light water is ( 1 H2 16 Heavy water is water containing at least one of the hydrogen isotopes, such as deuterium (D) and tritium (T).

[0025] The electrolytic unit 12 includes, for example, an electrolytic cell or electrolytic cell for electrolyzing water containing heavy water supplied from the raw material tank 11. For example, the electrolytic unit 12 is an electrolytic cell. The electrolytic unit 12 is connected to an anode supply path 10a and a cathode supply path 10b. In electrolytic apparatus 12, for example, the electrolytic reaction shown in the following formula (Equation 1) occurs. The electrolytic reaction in electrolytic apparatus 12 includes the electrolytic reaction of heavy water (D2O) and semi-heavy water (HDO) as shown in the following formula (Equation 1).

[0026]

number

[0027] For example, the electrolytic unit 12 discharges hydrogen (H2), deuterium (D2), hydrogen deuteride (HD), and hydrogen tritiate (HT), etc., obtained by the electrolytic reaction, into the anode supply channel 10a. The electrolytic unit 12 discharges oxygen (O2), obtained by the electrolytic reaction, into the cathode supply channel 10b.

[0028] The nitrogen tank 13 stores gases such as air containing nitrogen (N2). The nitrogen tank 13 is connected to the cathode supply passage 10c for the separator. The nitrogen tank 13 supplies gases such as air containing nitrogen (N2) to the cathode supply passage 10c for the separator.

[0029] The anode-side humidifier 14A is installed between the electrolytic unit 12 and the separator 15 in the anode supply path 10a. The anode-side humidifier 14A humidifies the hydrogen (H2), deuterium (D2), hydrogen deuteride (HD), and hydrogen tritiate (HT), etc., supplied from the electrolytic unit 12 with water, such as water vapor and liquid water. The cathode-side humidifier 14B is installed in the cathode supply passage 10c for the separator. The cathode-side humidifier 14B humidifies gases such as air containing nitrogen (N2) supplied from the nitrogen tank 13 with water, such as water vapor and liquid water.

[0030] The separator 15 includes, for example, a catalyst or fuel cell that separates hydrogen isotopes from hydrogen (H2), deuterium (D2), hydrogen deuteride (HD), and hydrogen tritiate (HT) supplied from the electrolytic unit 12 by an isotope exchange reaction. For example, the separator 15 is a fuel cell stack comprising a plurality of stacked fuel cell cells. A fuel cell cell comprises, for example, an ion exchange membrane (electrolyte membrane) 15a, an anode 15b and a cathode 15c provided on both sides of the thickness direction of the ion exchange membrane 15a, and an anode-side flow path 15d and a cathode-side flow path 15e.

[0031] The ion exchange membrane 15a includes, for example, a proton exchange membrane or an anion exchange membrane. The anode 15b includes, for example, a platinum-based anode catalyst and a gas diffusion layer. The cathode 15c includes, for example, a platinum-based cathode catalyst and a gas diffusion layer.

[0032] The anode-side flow path 15d is formed between the anode 15b and the separator 15b, for example, by an anode-side separator. The anode-side flow path 15d is connected to the anode-side humidifier 14A and the first anode-side condenser 16A (described later) by an anode supply path 10a outside the separator 15. Hydrogen (H2), deuterium (D2), hydrogen deuteride (HD), and hydrogen tritiate (HT), humidified with water such as water vapor and liquid, are supplied to the anode-side flow path 15d from the anode-side humidifier 14A.

[0033] The cathode-side flow path 15e is formed between the cathode 15c and the cathode 15c, for example, by a cathode-side separator. The cathode-side flow path 15e is connected to the cathode-side humidifier 14B and the first cathode-side condenser 16B (described later) by a separator cathode supply path 10c outside the separator 15. A gas, such as air containing nitrogen (N2) humidified with water vapor or liquid water, is supplied to the cathode-side flow path 15e from the cathode-side humidifier 14B.

[0034] Figure 2 shows an example of an isotope exchange reaction in the separator 15 of the hydrogen isotope separation system 10 of the embodiment. As shown in Figure 2, in the separator 15, isotope exchange reactions occur between water and hydrogen at the anode 15b and cathode 15c. Hydrogen isotopes such as deuterium (D) and tritium (T) move to the oxide side, and also move from the anode 15b side to the cathode 15c side through the ion exchange membrane 15a. For example, the exchange reaction shown in equation (2) below occurs at anode 15b, and the exchange reaction shown in equation (3) below occurs at cathode 15c. Note that the exchange reactions at anode 15b and cathode 15c include the exchange reactions obtained by replacing deuterium (D) with tritium (T) in hydrogen deuteride (HD) and semi-heavy water (HDO) in equations (2) and (3) below. Also, (g) in equations (2) and (3) below indicates the state of gas and vapor, etc.

[0035]

number

[0036]

number

[0037] In separator 15, for example, semi-heavy water (HDO), hydrogen deuteride (HD), tritiated water (HTO), and tritiated hydrogen (HT) move from the anode 15b side to the cathode 15c side via the ion exchange membrane 15a. In separator 15, for example, water (H2O) moves from the cathode 15c side to the anode 15b side via the ion exchange membrane 15a. At the anode 15b of the separator 15, for example, hydrogen (H2) along with water (H2O), semi-heavy water (HDO), and tritium water (HTO) are discharged to the external anode supply passage 10a toward the first anode-side condenser 16A. At the cathode 15c of the separator 15, for example, water (H2O) carried by nitrogen (N2) gas along with semi-heavy water (HDO) and tritium water (HTO) are discharged to the external first cathode-side condenser 16B.

[0038] The first anode-side condenser 16A is provided in the anode supply passage 10a. The first cathode-side condenser 16B is provided in the discharge passage on the cathode 15c side of the separator 15. The first anode-side condenser 16A and the first cathode-side condenser 16B each separate the fluid discharged from the anode-side flow path 15d and the cathode-side flow path 15e of the separator 15 into a gaseous component and a liquid component. The liquid component is, for example, light water and heavy water separated from the fluid by condensation.

[0039] For example, the gaseous component separated in the first anode condenser 16A is hydrogen (H2), and the liquid components are light water (H2O) and heavy water (HDO, HTO). For example, the gaseous component separated by the first anode condenser 16A is discharged toward the anode-side flow path 17d of the coupler 17, which will be described later. The liquid component is discharged, for example, into the first tank 31 of the heat transfer medium circuit 30, which will be described later. For example, the gaseous component separated in the first cathode-side condenser 16B is nitrogen (N2) or air, and the liquid components are light water (H2O) and heavy water (HDO, HTO). For example, the gaseous component separated by the first cathode-side condenser 16B is discharged to the outside via an on-off valve or the like. The liquid component is discharged, for example, to the first tank 31 of the heat transfer medium circuit 30 described later.

[0040] As shown in Figure 1, the coupler 17 includes, for example, a fuel cell that generates water (H2O) by recombining hydrogen (H2) supplied from the separator 15 and oxygen (O2) supplied from the electrolytic unit 12. For example, the coupler 17 is a fuel cell stack comprising a plurality of stacked fuel cell cells. A fuel cell cell comprises, for example, an ion exchange membrane (electrolyte membrane) 17a, an anode 17b and a cathode 17c provided on both sides of the thickness direction of the ion exchange membrane 17a, and an anode-side flow path 17d and a cathode-side flow path 17e.

[0041] The ion exchange membrane 17a includes, for example, a proton exchange membrane or an anion exchange membrane. The anode 17b includes, for example, a platinum-based anode catalyst and a gas diffusion layer. The cathode 17c includes, for example, a platinum-based cathode catalyst and a gas diffusion layer.

[0042] The anode-side channel 17d is formed between the anode 17b and the anode 17b, for example, by an anode-side separator. The anode-side channel 17d leads to the anode supply channel 10a and the anode discharge channel 10d outside the coupler 17. The cathode-side channel 17e is formed between the cathode 17c and the cathode 17c, for example, by a cathode-side separator. The cathode-side channel 17e leads to the cathode supply channel 10b and the cathode discharge channel 10e outside the coupler 17. Each fuel cell generates electricity through a catalytic reaction between hydrogen (H2) supplied to the anode 17b and oxygen (O2) supplied to the cathode 17c.

[0043] The second anode condenser 18A is provided in the anode discharge channel 10d. The second cathode condenser 18B is provided in the cathode discharge channel 10e. Each of the second anode condenser 18A and the second cathode condenser 18B separates the fluid discharged from the anode channel 17d and cathode channel 17e of the coupler 17 into a gaseous component and a liquid component. The liquid component is, for example, light water and heavy water separated from the fluid by condensation.

[0044] For example, the gaseous component separated in the second anode condenser 18A is hydrogen (H2), and the liquid components are light water (H2O) and heavy water (HDO, HTO). For example, the gaseous component separated by the second anode condenser 18A is discharged to the outside via the anode valve 19A. The liquid components are discharged, for example, to the first tank 31 of the heat transfer medium circuit 30 described later. For example, the gaseous component separated in the second cathode-side condenser 18B is nitrogen (N2) or air, and the liquid components are light water (H2O) and heavy water (HDO, HTO). For example, the gaseous component separated by the second cathode-side condenser 18B is discharged to the outside via the cathode-side on-off valve 19B. The liquid component is discharged, for example, to the first tank 31 of the heat transfer medium circuit 30 described later.

[0045] Figure 3 is a diagram showing the configuration of the heat transfer medium circuit 30 in the hydrogen isotope separation system 10 of the embodiment. As shown in Figures 1 and 3, the hydrogen isotope separation system 10 includes, for example, a heat transfer medium circuit 30 connected to heat transfer medium channels 14a, 15f, and 17f provided in the anode humidifier 14A, the separator 15, and the coupler 17, respectively. The heat transfer medium circuit 30 includes, for example, a first tank 31, a pump 32, a three-way valve 33, a first on-off valve 34, a heater 35, a second on-off valve 36, a second tank 37, a first temperature sensor 38A and a second temperature sensor 38B, and a water level sensor 39.

[0046] The first tank 31 stores a heat transfer medium, such as water. The discharge section of the first tank 31 is connected to the supply section of the heat transfer medium passage 17f of the coupler 17 by a first passage 30a, which is equipped with a pump 32, for example. The pump 32 circulates the heat transfer medium from the first tank 31 to the heat transfer medium flow path 17f of the coupler 17 via the first flow path 30a.

[0047] The discharge section of the heat transfer medium flow path 17f of the coupler 17 is connected, for example, to the inlet of the three-way valve 33 by a second flow path 30b. The three-way valve 33 comprises, for example, one inlet and two outlets (a first outlet and a second outlet). The three-way valve 33 switches the flow path between the inlet and either the first or second outlet. For example, the first outlet of the three-way valve 33 is connected to the injection section of the first tank 31 by a third flow path 30c. The second outlet of the three-way valve 33 is connected to the supply section of the heat transfer medium flow path 15f of the separator 15 by a fourth flow path 30d. Mode A of the three-way valve 33 is a state in which the flow path between the inlet and the first outlet is open, and mode B is a state in which the flow path between the inlet and the second outlet is open.

[0048] The section between the pump 32 and the coupler 17 in the first flow path 30a and the section between the coupler 17 and the three-way valve 33 in the second flow path 30b are connected, for example, by a fifth flow path 30e, which is provided with a first on-off valve 34 and a heater 35, so as to bypass the coupler 17. For example, the first on-off valve 34 and the heater 35 are arranged sequentially in the fifth flow path 30e, from the first flow path 30a to the second flow path 30b. The heater 35 heats the heat transfer medium flowing from the first flow path 30a to the second flow path 30b via the first on-off valve 34.

[0049] The discharge port of the heat transfer medium flow path 15f of the separator 15 is connected, for example, to the supply port of the heat transfer medium flow path 14a of the anode-side humidifier 14A by a sixth flow path 30f. The portion of the sixth flow path 30f between the discharge port of the heat transfer medium flow path 15f and the supply port of the heat transfer medium flow path 14a is connected, for example, to the injection port of the anode-side humidifier 14A by a seventh flow path 30g, which is provided with a second on-off valve 36. The injection port of the anode-side humidifier 14A injects, for example, water W for humidification into the anode-side humidifier 14A.

[0050] The discharge port of the anode-side humidifier 14A is connected, for example, to the inlet port of the second tank 37 by an eighth flow path 30h. The discharge port of the second tank 37 is connected, for example, to the inlet port of the first tank 31 by a ninth flow path 30j. For example, the liquid discharge ports of the first anode condenser 16A, the first cathode condenser 16B, the second anode condenser 18A, and the second cathode condenser 18B are connected to the injection ports of the first tank 31 by their respective 10th flow channels 30k. For example, the condensed water discharged from each of the condensers 16A, 16B, 18A, and 18B is supplied to the first tank 31 via their respective 10th flow channels 30k. The first tank 31 may also be equipped with, for example, an ion exchanger or the like to reduce the conductivity of the heat transfer medium being injected or discharged.

[0051] For example, the first channel 30a, second channel 30b, third channel 30c, and fifth channel 30e described above constitute the first flow passage 30A for circulating the heat transfer medium to the coupler 17. For example, the fourth channel 30d, sixth channel 30f, eighth channel 30h, and ninth channel 30j described above constitute the second flow passage 30B for circulating the heat transfer medium to the anode-side humidifier 14A.

[0052] The first temperature sensor 38A is provided, for example, in the second flow path 30b between the coupler 17 and the heater 35 and the three-way valve 33. The first temperature sensor 38A detects, for example, the temperature (first temperature) T1 of the heat transfer medium flowing from the coupler 17 or the heater 35 to the inlet of the three-way valve 33. The second temperature sensor 38B is installed, for example, inside the anode-side humidifier 14A. The second temperature sensor 38B detects, for example, the temperature (second temperature) T2 of the humidifying water W stored inside the anode-side humidifier 14A. The water level sensor 39 is installed, for example, inside the anode-side humidifier 14A. The water level sensor 39 detects, for example, the water level (water surface position) H of the humidifying water W stored inside the anode-side humidifier 14A.

[0053] The hydrogen isotope separation system 10 includes, for example, a control device 40 that comprehensively controls the operation of the hydrogen isotope separation system 10. For example, the control device 40 is a software function unit that functions when a predetermined program is executed by a processor such as a CPU (Central Processing Unit). The software function unit is an ECU (Electronic Control Unit) that includes a processor such as a CPU, a ROM (Read Only Memory) for storing programs, a RAM (Random Access Memory) for temporarily storing data, and electronic circuits such as a timer. At least a part of the control device 40 may be an integrated circuit such as an LSI (Large Scale Integration).

[0054] (Operation of the hydrogen isotope separation system) The operation of the hydrogen isotope separation system 10 according to this embodiment will be described below. Figure 4 is a flowchart showing the operation of the hydrogen isotope separation system 10 of the embodiment during startup. As shown in Figure 4, first the control device 40 starts the hydrogen isotope separation system 10 (step S01). Next, the control device 40 sets the three-way valve 33 to mode A, thereby allowing the second flow path 30b connected to the inlet of the three-way valve 33 and the third flow path 30c connected to the first outlet to pass through (step S02).

[0055] Next, the control device 40 determines whether the first temperature T1 detected by the first temperature sensor 38A is equal to or greater than the first predetermined temperature T1b (step S03). The first predetermined temperature T1b is, for example, the lower limit temperature required to ensure the desired operation of the anode-side humidifier 14A and the separator 15 by heating with a heat transfer medium. If the result of this determination is "NO", the control device 40 proceeds to step S04. On the other hand, if the result of this determination is "YES", the control device 40 proceeds to step S05. Then, the control device 40 causes the coupler 17 to operate at low efficiency or the heater 35 to operate (step S04). Then, the control device 40 returns the process to step S03.

[0056] Low-efficiency operation of the coupler 17 reduces power generation efficiency and cell voltage by, for example, reducing the amount of oxygen (O2) supplied to the cathode 17c of the coupler 17 compared to normal operation (so-called low-stoichiometry). Low-efficiency operation of the coupler 17 is, for example, warm-up operation during low-temperature startup, and as power generation efficiency decreases, the amount of heat generated (waste heat) increases, and the rate of heating of the coupler 17 increases.

[0057] Furthermore, the control device 40 sets the three-way valve 33 to mode B, thereby allowing the second flow path 30b connected to the inlet of the three-way valve 33 and the fourth flow path 30d connected to the second outlet to pass through (step S05). Next, the control device 40 determines whether the second temperature T2 detected by the second temperature sensor 38B is equal to or greater than the second predetermined temperature T2b (step S06). The second predetermined temperature T2b is, for example, the lower limit temperature required to ensure the desired humidification operation of the anode-side humidifier 14A. If the result of this determination is "NO", the control device 40 repeatedly executes the determination process in step S06. On the other hand, if the result of this determination is "YES", the control device 40 proceeds to step S07. Then, the control device 40 causes the coupler 17 to perform normal operation (step S07). Then, the control device 40 proceeds to the end of the process.

[0058] Figure 5 is a flowchart showing the operation of the hydrogen isotope separation system 10 of the embodiment after startup. Note that the series of processes from step S11 to step S14 shown in Figure 5 are repeatedly executed at predetermined timings. As shown in Figure 5, first, the control device 40 controls the amount of heat dissipated from the coupler 17 or the amount of heat heated by the heater 35 and the rotation speed of the pump 32 according to the first temperature T1 and second temperature T2 detected by the first temperature sensor 38A and the second temperature sensor 38B (step S11).

[0059] Next, the control device 40 determines whether the water level H detected by the water level sensor 39 is below a predetermined water level Ha (step S12). The predetermined water level Ha is, for example, the lower limit water level required to ensure the desired humidification operation of the anode-side humidifier 14A. If the result of this determination is "NO", the control device 40 proceeds to step S13. On the other hand, if the result of this determination is "YES", the control device 40 proceeds to step S14. Then, the control device 40 sets the second on-off valve 36 to closed (OFF) (step S13). Then, the control device 40 proceeds to the end of the process. Furthermore, the control device 40 sets the second on-off valve 36 to open (ON) (step S14). Then, the control device 40 proceeds to the end of the process.

[0060] Figure 6 shows an example of the correspondence between the amount of waste heat from the coupler 17, the rotational speed of the pump 32, the first temperature T1 and the second temperature T2, the operating mode of the three-way valve 33, the water level H of the humidifier, and the open / closed state of the second on-off valve 36 in the hydrogen isotope separation system 10 of the embodiment. As shown in Figure 6, for example, at time t0, in the stopped state of the hydrogen isotope separation system 10, the three-way valve 33 is set to mode A, and the first on-off valve 34 and the second on-off valve 36 are set to closed (OFF). When the hydrogen isotope separation system 10 is activated, such as at time t1, the three-way valve 33 is maintained in the A mode, the pump 32 starts operating, and the coupler 17 starts low-efficiency operation. As after time t1, the amount of waste heat of the coupler 17 is maintained at a predetermined amount Je, and the rotational speed of the pump 32 is maintained at a predetermined rotational speed Nc. Along with the circulation of the heat medium in the first flow path 30A, the first temperature T1 changes in an increasing trend from the initial temperature T1a towards the first predetermined temperature T1b (>T1a).

[0061] When the first temperature T1 reaches the first predetermined temperature T1b or higher, such as at time t2, the three-way valve 33 is switched from the A mode to the B mode, the rotational speed of the pump 32 is reduced, and the coupler 17 stops low-efficiency operation. As after time t2, the amount of waste heat of the coupler 17 is reduced to a predetermined amount Jb (<Je), and the rotational speed of the pump 32 is reduced to a predetermined rotational speed Na (<Nc). As a result, the first temperature T1 is maintained at the first predetermined temperature T1b. Along with the circulation of the heat medium in the first flow path 30A and the second flow path 30B connected by the three-way valve 33, the second temperature T2 changes in an increasing trend from the initial temperature T2a towards the second predetermined temperature T2b (>T2a).

[0062] When the second temperature T2 reaches the second predetermined temperature T2b or higher, such as at time t3, the operation at the start of the hydrogen isotope separation system 10 is terminated. After the start of the hydrogen isotope separation system 10, such as after time t3, the coupler 17 starts normal operation. For example, the amount of waste heat of the coupler 17 and the rotational speed of the pump 32 are controlled by feedback control or the like so as to maintain the first temperature T1 at the first predetermined temperature T1b and the second temperature T2 at the second predetermined temperature T2b. For example, at appropriate timings, such as from time t4 to time t7, the amount of waste heat is temporarily increased to a predetermined amount Jd (>Jb), and the rotational speed is increased to a predetermined rotational speed Nc (>Na). As a result, the first temperature T1 and the second temperature T2 are maintained. Also, for example, at appropriate timings, such as from time t7 to time t10, the amount of waste heat is temporarily reduced to a predetermined amount Jc (<Jd), and the rotational speed is reduced to a predetermined rotational speed Nb (<Nc). As a result, the first temperature T1 and the second temperature T2 are maintained.

[0063] When the water level H inside the anode-side humidifier 14A reaches a predetermined water level Ha (< initial water level Hc), such as at time t5 or time t8, the second on-off valve 36 is switched from closed (OFF) to open (ON). As the heat medium is supplied from the second flow path 30B and the seventh flow path 30g to the inside of the anode-side humidifier 14A, such as from time t5 to time t6 or from time t8 to time t9, the water level H changes in an increasing trend from the predetermined water level Ha toward the initial water level Hc. When the water level H reaches the initial water level Hc or higher, such as at time t6 or time t9, the second on-off valve 36 is switched from open (ON) to closed (OFF).

[0064] When the operation of the hydrogen isotope separation system 10 is stopped, such as at time t10, the three-way valve 33 is switched from mode B to mode A, and the coupler 17 and the pump 32 are stopped. After time t10, the amount of exhaust heat, the rotational speed, the first temperature T1, and the second temperature T2 change in a decreasing trend, and the water level H is maintained at a predetermined water level Hb (< Hc).

[0065] As described above, according to the hydrogen isotope separation system 10 of the embodiment, when the first temperature T1 is less than the first predetermined temperature T1b, the first flow path 30A and the second flow path 30B are blocked, so that the temperature of the heat medium in the first flow path 30A can be rapidly increased. When the first temperature T1 is greater than or equal to the first predetermined temperature T1b, the first flow path 30A and the second flow path 30B are connected, so that the separator 15 and the anode-side humidifier 14A can be appropriately heated by the relatively high-temperature heat medium. While suppressing the complexity of the configuration of the heat medium circuit 30, the temperatures of the coupler 17, the separator 15, and the anode-side humidifier 14A can be appropriately controlled.

[0066] By providing the seventh flow path 30g that connects the second flow path 30B and the inside of the anode-side humidifier 14A, the heat medium of the heat medium circuit 30 can be used in combination as the water W for humidification in the anode-side humidifier 14A. For example, it is possible to suppress the complexity of the system configuration by eliminating the need for dedicated equipment for supplying the water W for humidification. Since the opening and closing of the second on-off valve 36 is controlled according to the water level H, the amount of humidifying water W stored inside the anode-side humidifier 14A can be properly maintained.

[0067] When the first temperature T1 is less than the first predetermined temperature T1b, the coupler 17 operates at low efficiency, which allows the temperature of the heat transfer medium in the first flow passage 30A to rise rapidly due to the increase in waste heat resulting from the decrease in power generation efficiency. By providing the heater 35, the temperature of the heat transfer medium in the first flow passage 30A can be easily and quickly raised, regardless of the presence or operation of the coupler 17.

[0068] By providing a tenth flow path 30k connecting each of the first anode condenser 16A, the first cathode condenser 16B, the second anode condenser 18A, and the second cathode condenser 18B to the first tank 31, the condensed water discharged from each of the condensers 16A, 16B, 18A, and 18B can be used as the heat transfer medium for the heat transfer medium circuit 30. For example, this eliminates the need for dedicated equipment to supply the heat transfer medium, thereby suppressing the complexity of the system configuration.

[0069] In the heat transfer medium circuit 30, the heat transfer medium flows from the separator 15 to the anode-side humidifier 14A, which allows the warming of the separator 15, which has a relatively higher operating temperature, to be prioritized over the temperature rise of the anode-side humidifier 14A. This suppresses the dew point of the humidified inert gas supplied from the anode-side humidifier 14A to the anode 15b of the separator 15 from becoming higher than the temperature of the separator 15, thereby suppressing a decrease in separation efficiency due to condensation occurring inside the separator 15, for example.

[0070] (modified version) Modified examples of the embodiments are described below. Note that parts identical to those in the embodiments described above are denoted by the same reference numerals, and their descriptions are omitted or simplified. In the embodiment described above, the heat transfer medium of the heat transfer medium circuit 30 is supplied to the heat transfer medium flow path 14a or inside the anode-side humidifier 14A. However, it is not limited to this, and for example, in addition to the anode-side humidifier 14A, it may also be supplied to the heat transfer medium flow path or inside the cathode-side humidifier 14B or other humidifiers. In the embodiment described above, the condensed water discharged from each of the first anode condenser 16A, the first cathode condenser 16B, the second anode condenser 18A, and the second cathode condenser 18B was used as the heat transfer medium for the heat transfer medium circuit 30. However, the embodiment is not limited to this, and for example, the condensed water discharged from at least one of the first anode condenser 16A, the first cathode condenser 16B, the second anode condenser 18A, and the second cathode condenser 18B may be used as the heat transfer medium for the heat transfer medium circuit 30.

[0071] In the embodiment described above, the heat transfer medium circuit 30 is provided with a second on-off valve 36 for switching between on and off, but it is not limited to this, and for example, in addition to on and off, it may also be provided with a control valve for adjusting the flow rate. In this case, only a portion of the heat transfer medium of the heat transfer medium circuit 30 may be supplied to the inside of the anode-side humidifier 14A.

[0072] In the embodiment described above, the heat transfer medium in the heat transfer medium circuit 30 is heated by either the low-efficiency operation of the coupler 17 or the operation of the heater 35. However, the embodiment is not limited to this, and for example, the heat transfer medium in the heat transfer medium circuit 30 may be heated by both the low-efficiency operation of the coupler 17 and the operation of the heater 35.

[0073] In the embodiments described above, the hydrogen isotope separation system 10 is said to include a coupler 17, but it is not limited to this, and the coupler 17 may be omitted. Figure 7 is a diagram showing the configuration of the heat transfer medium circuit 30 in a modified example of the embodiment, the hydrogen isotope separation system 10A. As shown in Figure 7, in the modified hydrogen isotope separation system 10A, the coupler 17, the second anode condenser 18A, and the second cathode condenser 18B in the hydrogen isotope separation system 10 of the embodiment described above are omitted. The heat transfer medium circuit 30 in the modified hydrogen isotope separation system 10A includes a first flow path 30a connected from the discharge portion of the first tank 31 to the inlet portion of the three-way valve 33. In the modified first flow path 30a, for example, the pump 32, the first on-off valve 34, and the heater 35 are arranged sequentially from the discharge portion of the first tank 31 to the inlet portion of the three-way valve 33. In this case, for example, the heat transfer medium in the heat transfer medium circuit 30 is heated by the heater 35.

[0074] According to the modified hydrogen isotope separation system 10A, when the first temperature T1 is less than the first predetermined temperature T1b, the first flow passage 30A and the second flow passage 30B are blocked, so the temperature of the heat transfer medium in the first flow passage 30A can be rapidly raised by the heater 35. When the first temperature T1 is equal to or greater than the first predetermined temperature T1b, the first flow passage 30A and the second flow passage 30B are connected, so the separator 15 and the anode-side humidifier 14A can be appropriately heated by the relatively high-temperature heat transfer medium. The temperature of the separator 15 and the anode-side humidifier 14A can be appropriately controlled while suppressing complexity in the configuration of the heat transfer medium circuit 30.

[0075] The embodiments of the present invention are presented as examples and are not intended to limit the scope of the invention. These embodiments can be carried out in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of Symbols]

[0076] 10, 10A…Hydrogen isotope separation system, 10a…Anode supply path, 10b…Cathode supply path, 10c…Cathode supply path for separator, 10d…Anode discharge path, 10e…Cathode discharge path, 11…Raw material tank, 12…Electrolyzer, 13…Nitrogen tank, 14A…Anode-side humidifier (humidifier), 14B…Cathode-side humidifier, 15…Separator, 15a…Ion exchange membrane, 15b…Anode, 15c…Cathode, 16A…First anode-side condenser (condenser), 16B…First cathode-side condenser (condenser), 17…Coupler, 17a…Ion exchange membrane, 17b…Anode, 17c…Cathode, 18 A...Second anode condenser (condenser), 18B...Second cathode condenser (condenser), 19A...Anode on-off valve, 19B...Cathode on-off valve, 30...Heat transfer fluid circuit, 30g...Seventh flow path (humidification supply flow path), 30A...First flow path, 30B...Second flow path, 31...First tank, 32...Pump, 30k...Tenth flow path (condensate flow path), 33...Three-way valve (switching valve), 34...First on-off valve, 35...Heater, 36...Second on-off valve (supply switching valve), 37...Second tank, 38A...First temperature sensor (temperature sensor), 38B...Second temperature sensor, 39...Water level sensor (humidifier sensor), 40...Control device.

Claims

1. A coupler that generates electricity using light hydrogen obtained from heavy water containing light water, A humidifier that humidifies the fluid supplied toward the coupling, A heat transfer medium circuit through which a heat transfer medium that exchanges heat with each of the aforementioned coupler and humidifier flows, A control device for controlling the heat transfer circuit and Equipped with, The aforementioned heat transfer circuit is The coupling has a first flow passage through which the heat transfer medium flows, The humidifier has a second flow passage through which the heat transfer medium is circulated, A switching valve for switching the connection and disconnection between the first flow passage and the second flow passage, A temperature sensor that detects a temperature related to the temperature of the heat transfer medium flowing through the first flow passage, Equipped with, The control device is When the temperature detected by the temperature sensor is above a predetermined temperature, the switching valve connects the first flow passage and the second flow passage. Hydrogen isotope separation system.

2. The aforementioned heat transfer circuit is A humidification supply channel supplies at least a portion of the heat transfer medium flowing through the second flow channel to the inside of the humidifier for humidification, A supply switching valve that switches the connection and disconnection between the second flow passage and the humidifying supply flow passage, Equipped with The hydrogen isotope separation system according to claim 1.

3. The aforementioned heat transfer circuit is The humidifier is equipped with a humidifier sensor that detects a state quantity related to the amount of water used for humidification stored inside the humidifier. The control device is When the state quantity detected by the humidifier sensor is below a predetermined value, the supply switching valve connects the second flow passage and the humidifier supply flow path. The hydrogen isotope separation system according to claim 2.

4. The control device is If the temperature detected by the temperature sensor is below the predetermined temperature, the power generation efficiency of the coupler is reduced. A hydrogen isotope separation system according to any one of claims 1 to 3.

5. The aforementioned heat transfer circuit is The first flow passage is equipped with a heater for heating the heat transfer medium. The hydrogen isotope separation system according to claim 4.

6. The device comprises a condenser provided for at least one of the fluids supplied to the coupler and the fluid discharged from the coupler, The aforementioned heat transfer circuit is The system includes a condensate flow channel that supplies the condensate discharged from the condenser to the first flow channel as the heat transfer medium. The hydrogen isotope separation system according to claim 4.

7. The separator is positioned between the humidifier and the coupler and includes an ion exchange membrane and a catalyst for separating hydrogen isotopes. The second flow passage allows the heat transfer medium to flow to the humidifier and the separator. The hydrogen isotope separation system according to claim 6.

8. A separator having an ion exchange membrane and a catalyst for separating hydrogen isotopes, A humidifier that humidifies the fluid supplied toward the separator, A heat transfer medium circuit through which a heat transfer medium that exchanges heat with each of the separator and the humidifier flows, A control device for controlling the heat transfer circuit and Equipped with, The aforementioned heat transfer circuit is A heater for heating the heat transfer medium, The heater has a first flow passage through which the heat transfer medium flows, The humidifier has a second flow passage through which the heat transfer medium is circulated, A switching valve for switching the connection and disconnection between the first flow passage and the second flow passage, A temperature sensor that detects a temperature related to the temperature of the heat transfer medium flowing through the first flow passage, Equipped with, The control device is When the temperature detected by the temperature sensor is above a predetermined temperature, the switching valve connects the first flow passage and the second flow passage. Hydrogen isotope separation system.

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