Hydrogen isotope separation system

Abstract

This invention provides a hydrogen isotope separation system that can suppress the degradation of performance during startup. [Solution] The hydrogen isotope separation system 10 comprises a separator 15 having an ion exchange membrane 15a, an anode 15b, and a cathode 15c. The hydrogen isotope separation system 10 comprises an anode supply path 10a that supplies light hydrogen containing one or more hydrogen isotopes toward the anode 15b, and a cathode supply path 10b that supplies cathode gas toward the cathode 15c. The hydrogen isotope separation system 10 comprises a mass spectrometer 20 and a control device 40. The mass spectrometer 20 detects the isotope ratio related to the concentration of hydrogen isotopes in the gas supplied to the anode 15b of the separator 15 and the gas discharged from the anode 15b. The control device 40 increases the separation coefficient α when the supply-side concentration ratio, which is the concentration ratio of deuterium and tritium to light hydrogen on the supply side of the anode 15b, is less than or equal to a first predetermined value.

Description

Technical Field

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

Background Art

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

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 a decrease in the overall system capacity at the time of system startup. For example, in the case of a system using an ion exchange membrane for separation of hydrogen isotopes as in the above conventional technology, if the amounts of heavy water and tritium components contained in the electrolytic products at startup are smaller than those during normal operation, the concentrations of deuterium and tritium in the exhaust may increase.

[0005] The present application aims to achieve suppression of a decrease in capacity at startup for solving the above problems. And it contributes to energy efficiency by extension. [Means for solving the problem]

[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, the hydrogen isotope separation system 10 in the embodiment) includes an ion exchange membrane (for example, the ion exchange membrane 15a in the embodiment), an anode (for example, the anode 15b in the embodiment) and a cathode (for example, the cathode 15c in the embodiment) provided on both sides in the thickness direction of the ion exchange membrane, a separator (for example, the separator 15 in the embodiment) for separating hydrogen isotopes, an anode supply passage (for example, the anode supply passage 10a in the embodiment) for supplying light hydrogen containing at least one type of hydrogen isotope toward the anode, a cathode supply passage (for example, the cathode supply passage 10b in the embodiment) for supplying cathode gas toward the cathode, and an anode discharge passage (for example, the anode discharge passage 10c in the embodiment) and a cathode through which the fluid discharged from the anode and cathode flows. The system comprises a sword discharge path (for example, a cathode discharge path 10d in the embodiment), a state quantity acquisition unit (for example, a mass spectrometer 20 in the embodiment) that acquires state quantities related to the hydrogen isotope concentrations on the supply side and discharge side of the anode, and a control device (for example, a control device 40 in the embodiment). The control device sets a separation coefficient (for example, a separation coefficient α in the embodiment) which is the ratio of the supply side concentration ratio to the discharge side concentration ratio, based on the hydrogen isotope concentrations corresponding to the state quantities acquired by the state quantity acquisition unit, using the supply side concentration ratio, which is the concentration ratio of deuterium and tritium to light hydrogen on the supply side of the anode, and the discharge side concentration ratio, which is the concentration ratio of deuterium and tritium to light hydrogen on the discharge side of the anode. The control device then performs control to increase the separation coefficient when the supply side concentration ratio is less than or equal to a predetermined value (for example, a first predetermined value in the embodiment).

[0007] (2) In the hydrogen isotope separation system described in (1) above, the predetermined value may be the supply-side concentration ratio in a standard operating state other than when the separator is started up or stopped.

[0008] (3) In the hydrogen isotope separation system described in (2) above, the control device may set a predetermined discharge side concentration ratio (for example, a second predetermined value in the embodiment) as the discharge side concentration ratio in the standard operating state, and stop the control that increases the separation coefficient when the discharge side concentration ratio is less than or equal to the predetermined discharge side concentration ratio which is less than the predetermined value.

[0009] (4) The hydrogen isotope separation system described in any one of (1) to (3) above includes an electrolytic device (for example, electrolytic device 12 in the embodiment) provided in the anode supply path for electrolyzing heavy water containing light water, and the control device may perform control to increase the separation coefficient when the supply side concentration ratio at system startup is less than or equal to the predetermined value.

[0010] (5) In the hydrogen isotope separation system described in (4) above, the control device may increase the separation coefficient by performing at least one of the following: applying current to the separator, increasing the humidity of the fluid supplied to the anode, increasing the humidity of the fluid supplied to the cathode, decreasing the flow rate of the fluid supplied to the anode, and increasing the flow rate of the fluid supplied to the cathode. [Effects of the Invention]

[0011] According to (1) above, by providing a control device that performs control to increase the separation coefficient when the supply-side concentration ratio is below a predetermined value, it is possible to suppress an increase in the concentration of deuterium and tritium contained in the fluid discharged from the separator.

[0012] In the case of (2) above, even in conditions where the supply-side concentration ratio tends to decrease, such as during the startup and shutdown processes of the separator, the increase in the concentration of deuterium and tritium contained in the fluid discharged from the separator can be suppressed by implementing control to increase the separation coefficient.

[0013] In the case of (3) above, the control to increase the separation coefficient is continued until the discharge side concentration ratio reaches or below a predetermined discharge side concentration ratio, so that the increase in the concentration of deuterium and tritium contained in the fluid discharged from the separator can be effectively suppressed.

[0014] In the case of (4) above, for example, even when the electrolysis efficiency of the electrolytic unit is relatively reduced during system startup, the control to increase the separation coefficient can be implemented to suppress an increase in the concentration of deuterium and tritium contained in the fluid discharged from the separator.

[0015] In the case of (5) above, the separation coefficient can be increased appropriately. [Brief explanation of the drawing]

[0016] [Figure 1] A diagram illustrating the configuration of a hydrogen isotope separation system according to an embodiment of the present invention. [Figure 2] A figure showing an example of an isotope exchange reaction in the separator of a hydrogen isotope separation system according to an embodiment of the present invention. [Figure 3] A flowchart illustrating the operation of a hydrogen isotope separation system according to an embodiment of the present invention. [Figure 4] A figure showing an example of the time evolution of the D concentration obtained by the hydrogen isotope separation system of the embodiment and comparative example of the present invention. [Modes for carrying out the invention]

[0017] Hereinafter, an embodiment of the hydrogen isotope separation system of the present invention will be described with reference to the attached drawings. Figure 1 is a diagram showing the configuration of a hydrogen isotope separation system 10 according to an embodiment. As shown in FIG. 1, the hydrogen isotope separation system 10 of the embodiment includes, for example, an anode supply path 10a and a cathode supply path 10b, an anode discharge path 10c and a cathode discharge path 10d, a raw material tank 11, an electrolyzer 12, a nitrogen tank 13, an anode side humidifier 14A and a cathode side humidifier 14B, a separator 15, an anode side condenser 16A and a cathode side condenser 16B, anode side on-off valves 17A and 17B, and anode side tanks 18A and 18B, and cathode side tanks 18B.

[0018] The raw material tank 11 stores, for example, water containing heavy water and light water. The raw material tank 11 is connected to the anode supply path 10a. The raw material tank 11 supplies water containing heavy water and light water to the electrolyzer 12 via the anode supply path 10a. Note that light water is ( 1 H2 16 O), and heavy water is water containing at least one of hydrogen isotopes such as deuterium (D) and tritium (T).

[0019] The electrolyzer 12 includes, for example, an electrolytic cell or an electrolytic cell that electrolyzes water containing heavy water supplied from the raw material tank 11. For example, the electrolyzer 12 is an electrolytic cell. The electrolyzer 12 is connected to the anode supply path 10a. In the electrolyzer 12, for example, an electrolytic reaction shown in the following mathematical formula (Equation 1) occurs. The electrolytic reaction in the electrolyzer 12 includes an electrolytic reaction for electrolyzing heavy water (D2O) and semi-heavy water (HDO) in the following mathematical formula (Equation 1).

[0020]

Equation

[0021] For example, the electrolytic unit 12 discharges hydrogen (H2), deuterium (D2), tritium (T2), 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, to the outside other than the anode supply channel 10a. For example, the electrolytic unit 12 may supply the oxygen (O2), obtained by the electrolytic reaction, to an external coupling device (not shown), such as a fuel cell. For example, the coupling device (not shown) may produce water (H2O) by recombining hydrogen (H2) supplied from the separator 15 (described later) and oxygen (O2) supplied from the electrolytic unit 12 in a catalytic reaction.

[0022] The nitrogen tank 13 stores gases such as air containing nitrogen (N2). The nitrogen tank 13 is connected to the cathode supply passage 10b. The nitrogen tank 13 supplies gases such as air containing nitrogen (N2) to the cathode supply passage 10b.

[0023] 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), tritium (T2), 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 path 10b. The cathode-side humidifier 14B humidifies gases such as air containing nitrogen (N2) supplied from the nitrogen tank 13 with water vapor and liquid water, for example.

[0024] The separator 15 includes, for example, a catalyst or fuel cell that separates hydrogen isotopes from hydrogen (H2), deuterium (D2), tritium (T2), 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.

[0025] 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.

[0026] The anode-side channel 15d is formed between the anode 15b and the separator 15, for example, by an anode-side separator. The anode-side channel 15d is connected to the anode-side humidifier 14A by an anode supply channel 10a outside the separator 15. Hydrogen (H2), deuterium (D2), tritium (T2), hydrogen deuteride (HD), and hydrogen tritiate (HT), humidified with water such as water vapor and liquid, are supplied to the anode-side channel 15d from the anode-side humidifier 14A.

[0027] The cathode-side channel 15e is formed between the cathode 15c and the cathode 15c by, for example, a cathode-side separator. The cathode-side channel 15e is connected to the cathode-side humidifier 14B by a cathode supply channel 10b outside the separator 15. A gas, such as air containing nitrogen (N2) humidified with water, such as water vapor and liquid water, is supplied to the cathode-side channel 15e from the cathode-side humidifier 14B.

[0028] 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 (Equation 2) below occurs at anode 15b, and the exchange reaction shown in equation (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 (Equation 2) and (Equation 3) below. Also, (g) in equations (Equation 2) and (Equation 3) below indicates the state of gas and vapor, etc.

[0029]

number

[0030]

number

[0031] 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, water (H2O), semi-heavy water (HDO), and tritiated water (HTO) are discharged to the external anode discharge channel 10c along with hydrogen (H2). At the cathode 15c of the separator 15, for example, water (H2O) carried by nitrogen (N2) gas is discharged to the external cathode discharge channel 10d along with semi-heavy water (HDO) and tritiated water (HTO).

[0032] As shown in Figure 1, the anode condenser 16A is provided in the anode discharge channel 10c. The cathode condenser 16B is provided in the cathode discharge channel 10d. The anode condenser 16A and the cathode condenser 16B each separate the fluid discharged from the anode channel 15d and the cathode channel 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.

[0033] For example, the gaseous component separated in the 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 anode condenser 16A is discharged to the outside via the anode valve 17A. The liquid components are discharged, for example, to the anode tank 18A. As mentioned above, the hydrogen (H2) discharged from the anode condenser 16A may be supplied to an external fuel cell or other coupling device (not shown) and used for power generation by catalytic reaction and water (H2O) production. For example, the gaseous component separated in the 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 cathode-side condenser 16B is discharged to the outside via the cathode-side on / off valve 17B. The liquid component is discharged, for example, to the cathode-side tank 18B.

[0034] The hydrogen isotope separation system 10 includes, for example, a supply-side branch 10e and a discharge-side branch 10f, a first on-off valve 19A and a second on-off valve 19B, a mass spectrometer 20, and a power supply unit 21.

[0035] The supply-side branch line 10e connects, for example, the section between the electrolytic heater 12 and the anode-side humidifier 14A in the anode supply line 10a to the mass spectrometer 20. The discharge-side branch passage 10f connects, for example, the downstream portion of the anode-side on-off valve 17A in the anode discharge passage 10c to the mass spectrometer 20.

[0036] The first on-off valve 19A is located, for example, in the supply-side branch passage 10e. The second on-off valve 19B is located, for example, in the discharge-side branch passage 10f. As will be described later, the first on-off valve 19A and the second on-off valve 19B are switched from closed (OFF) to open (ON) when, for example, the concentration of hydrogen isotopes is detected on the supply side and discharge side, respectively, to the separator 15.

[0037] The mass spectrometer 20 detects, for example, the isotopic ratios related to the hydrogen isotope concentrations in the gas supplied to the anode 15b of the separator 15 (anode gas) and the gas discharged from the anode 15b (anode off gas).

[0038] The power supply unit 21 is connected, for example, to the anode 15b and cathode 15c of the separator 15 and applies current to the separator 15.

[0039] The hydrogen isotope separation system 10 includes, for example, a heat transfer medium circuit 30 and a control device 40. The heat transfer medium circuit 30 is connected, for example, to heat transfer medium flow paths (not shown) provided in the anode-side humidifier 14A and cathode-side humidifier 14B and the separator 15. The heat transfer medium circuit 30 includes, for example, a heater 31 for heating the heat transfer medium, a first temperature sensor 32, a second temperature sensor 33, and a third temperature sensor 34. The heat transfer medium circuit 30 forms a circulation circuit that circulates the heat transfer medium heated by the heater 31.

[0040] The heat transfer medium circuit 30 connects, for example, the heater 31, the separator 15, the cathode-side humidifier 14B, and the anode-side humidifier 14A in series sequentially from the upstream side to the downstream side along the flow direction of the first heat transfer medium. The heat transfer medium heated by the heater 31 is first supplied to the separator 15, thereby heating the separator 15 to a predetermined operating temperature. Next, the heat medium at the first temperature T1 after heating the separator 15 is supplied to the cathode-side humidifier 14B to heat the cathode-side humidifier 14B. The first temperature sensor 32 is disposed, for example, between the separator 15 and the cathode-side humidifier 14B to detect the first temperature T1 of the heat medium.

[0041] Next, the heat medium at the second temperature T2 (<T1) after heating the cathode-side humidifier 14B is supplied to the anode-side humidifier 14A to heat the anode-side humidifier 14A. The second temperature sensor 33 is disposed, for example, between the cathode-side humidifier 14B and the anode-side humidifier 14A to detect the second temperature T2 of the heat medium. Then, the heat medium at the third temperature T3 (<T2) after heating the anode-side humidifier 14A is returned to the heater 31. The third temperature sensor 34 is disposed, for example, between the anode-side humidifier 14A and the heater 31 to detect the third temperature T3 of the heat medium.

[0042] The control device 40 comprehensively controls the operation of the hydrogen isotope separation system 10, for example. For example, the control device 40 is a software functional unit that functions when a predetermined program is executed by a processor such as a CPU (Central Processing Unit). The software functional unit is an ECU (Electronic Control Unit) including a processor such as a CPU, a ROM (Read Only Memory) for storing a program, a RAM (Random Access Memory) for temporarily storing data, and an electronic circuit such as a timer. Note that at least a part of the control device 40 may be an integrated circuit such as an LSI (Large Scale Integration).

[0043] (Operation of Hydrogen Isotope Separation System) The operation of the hydrogen isotope separation system 10 of the embodiment will be described below. FIG. 3 is a flowchart showing the operation of the hydrogen isotope separation system 10 of the embodiment. As shown in Figure 3, first, the control device 40 detects the isotope ratio related to the concentration of hydrogen isotopes in the gas (anode gas) supplied to the anode 15b of the separator 15 by the mass spectrometer 20 (step S01).

[0044] Next, the control device 40 determines whether the supply-side concentration ratio, which is the concentration ratio of deuterium and tritium to light hydrogen in the anode gas, is less than or equal to a first predetermined value (step S02). The first predetermined value is, for example, the supply-side concentration ratio in the standard operating state during normal operation, excluding the start-up and stop-down processes of the separator 15. If the result of this determination is "NO", the control device 40 proceeds to the end of the process. On the other hand, if the result of this determination is "YES", the control device 40 proceeds to step S03.

[0045] Next, the control device 40 starts the separation efficiency improvement process (step S03). The separation efficiency improvement process is, for example, a process to increase the separation coefficient α shown in the following formula (Equation 4). As shown in the following formula (Equation 4), the separation coefficient α is the ratio of the supply-side concentration ratio to the discharge-side concentration ratio, which is the ratio of the concentration Tb of deuterium and tritium to the concentration Hb of light hydrogen at the supply side of the anode 15b, and the discharge-side concentration ratio (=Ta / Ha), which is the ratio of the concentration Ta of deuterium and tritium to the concentration Ha of light hydrogen at the discharge side of the anode 15b.

[0046]

number

[0047] In the separation efficiency improvement process, at least one of the following is performed: applying current to the separator 15, increasing the humidity of the anode gas supplied to the anode 15b, increasing the humidity of the cathode gas supplied to the cathode 15c, reducing the flow rate of the anode gas supplied to the anode 15b, and increasing the flow rate of the cathode gas supplied to the cathode 15c.

[0048] For example, the control device 40 increases the separation efficiency by applying current to the separator 15, thereby facilitating the exchange reactions shown in the above equations (Equation 2) and (Equation 3). For example, the control device 40 increases the amount of water (H2O) in the exchange reaction shown in formulas (Equation 2) and (Equation 3) by increasing the humidity of the anode gas supplied to the anode 15b and increasing the humidity of the cathode gas supplied to the cathode 15c. The control device 40 increases the separation efficiency by making the exchange reaction shown in formulas (Equation 2) and (Equation 3) more likely to occur.

[0049] For example, the control device 40 increases the fluid residence time on the anode catalyst by reducing the flow rate of the anode gas supplied to the anode 15b, thereby increasing the separation efficiency by increasing the reaction time. For example, the control device 40 increases the amount of water (H2O) that moves from the cathode 15c side to the anode 15b side via the ion exchange membrane 15a by increasing the flow rate of cathode gas supplied to the cathode 15c. The control device 40 increases the separation efficiency by making the exchange reactions shown in the above equations (Equation 2) and (Equation 3) more likely to occur.

[0050] Next, the control device 40 detects the isotope ratio related to the concentration of hydrogen isotopes in the gas (anode off-gas) discharged from the anode 15b of the separator 15 by the mass spectrometer 20 (step S04).

[0051] Next, the control device 40 determines, for example, whether the discharge-side concentration ratio, which is the concentration ratio of deuterium and tritium to light hydrogen in the anode off-gas, is less than or equal to a second predetermined value and less than a first predetermined value (step S05). The second predetermined value is, for example, the discharge-side concentration ratio in the standard operating state during normal operation, other than during the start-up and stop-down processes of the separator 15. If the result of this determination is "NO", the control device 40 returns to step S03. On the other hand, if the result of this determination is "YES", the control device 40 proceeds to step S06. Next, the control device 40 stops the execution of the separation efficiency improvement process (step S06). Then, the control device 40 proceeds to the end of the process.

[0052] Figure 4 shows an example of the time evolution of the D concentration obtained by the hydrogen isotope separation systems of the embodiment and comparative example. The D concentrations shown in Figure 4 are the concentrations of deuterium and tritium in the anode gas and anode off-gas, respectively. The embodiment describes a separation efficiency enhancement treatment performed when the supply-side concentration ratio is below a first predetermined value, while the comparative example describes a case where no separation efficiency enhancement treatment is performed. As shown in Figure 4, the D concentration in the anode gas (supply side) tends to increase from the time the hydrogen isotope separation system 10 is started up, as the electrolysis efficiency of the electrolytic unit 12 increases. The separation coefficient α shown in the above formula (Equation 4) tends to increase as the amount of heavy water and tritium components contained in the electrolytic product increases. As a result, for example, when the amount of heavy water and tritium components contained in the electrolytic product is relatively small, as in the initial stages of system startup in the comparative example, the separation coefficient α decreases compared to normal operation, and the D concentration in the anode off-gas (discharge side) may increase. In contrast, in this embodiment, by performing a separation efficiency increasing treatment when the supply side concentration ratio is below a first predetermined value, it is possible to suppress the decrease in the separation coefficient α and the increase in the D concentration in the anode off-gas (discharge side), even in the initial stages of system startup.

[0053] As described above, the hydrogen isotope separation system 10 of the embodiment includes a control device 40 that performs control to increase the separation coefficient α when the supply-side concentration ratio is below a first predetermined value, thereby suppressing an increase in the concentration of deuterium and tritium contained in the fluid discharged from the separator 15. For example, even in conditions where the supply-side concentration ratio tends to decrease, such as during the startup and shutdown processes of the separator 15, the control that increases the separation coefficient α can suppress an increase in the concentration of deuterium and tritium contained in the fluid discharged from the separator 15.

[0054] Since the control to increase the separation coefficient α is continued until the discharge side concentration ratio reaches a second predetermined value or less, the increase in the concentration of deuterium and tritium contained in the fluid discharged from the separator 15 can be effectively suppressed. For example, even during system startup when the electrolysis efficiency of the electrolytic unit 12 is relatively reduced, the control that increases the separation coefficient α can suppress an increase in the concentration of deuterium and tritium contained in the fluid discharged from the separator 15.

[0055] (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 control device 40 is said to detect isotope ratios related to the concentrations of hydrogen isotopes in the anode gas and anode-off gas, respectively, using the mass spectrometer 20, but it is not limited to this. For example, the control device 40 may obtain isotope ratios related to the concentrations of hydrogen isotopes in the anode gas and anode-off gas, respectively, at any given time by predetermined calculation processing based on the initial concentrations of hydrogen isotopes in the anode gas and anode-off gas, respectively.

[0056] 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]

[0057] 10...Hydrogen isotope separation system, 10a...Anode supply path, 10b...Cathode supply path, 10c...Anode discharge path, 10d...Cathode discharge path, 11...Raw material tank, 12...Electrolyzer, 13...Nitrogen tank, 14A...Anode-side humidifier, 14B...Cathode-side humidifier, 15...Separator, 15a...Ion exchange membrane, 15b...Anode, 15c...Cathode, 16A...Anode-side condenser, 16 B... Cathode-side condenser, 17A... Anode-side on-off valve, 17B... Cathode-side on-off valve, 18A... Anode-side tank, 18B... Cathode-side tank, 19A... First on-off valve, 19B... Second on-off valve, 20... Mass spectrometer (state quantity acquisition unit), 21... Power supply unit, 30... Heat transfer fluid circuit, 31... Heater, 32... First temperature sensor, 33... Second temperature sensor, 34... Third temperature sensor, 40... Control device.

Claims

1. A separator for separating hydrogen isotopes, comprising an ion exchange membrane and an anode and a cathode provided on both sides of the ion exchange membrane in the thickness direction, an anode supply path that supplies light hydrogen containing at least one type of hydrogen isotope toward the anode, A cathode supply path for supplying cathode gas toward the cathode, an anode discharge channel and a cathode discharge channel through which the fluid discharged from the anode and cathode flows, A state quantity acquisition unit that acquires state quantities related to the hydrogen isotope concentration on the supply side and discharge side of the anode, Control device and Equipped with, The control device is Based on the hydrogen isotope concentrations corresponding to the state quantities obtained by the state quantity acquisition unit, a separation coefficient is set, which is the ratio of the supply-side concentration ratio to the discharge-side concentration ratio, using the supply-side concentration ratio, which is the concentration ratio of deuterium and tritium to light hydrogen at the supply-side of the anode, and the discharge-side concentration ratio, which is the concentration ratio of deuterium and tritium to light hydrogen at the discharge-side of the anode. When the supply-side concentration ratio is below a predetermined value, control is executed to increase the separation coefficient. Hydrogen isotope separation system.

2. The predetermined value is the supply-side concentration ratio under standard operating conditions other than when the separator is started up or stopped. The hydrogen isotope separation system according to claim 1.

3. The control device is The predetermined discharge side concentration ratio is defined as the discharge side concentration ratio under the standard operating conditions. When the discharge side concentration ratio is less than or equal to the predetermined discharge side concentration ratio (which is less than the predetermined value), the control for increasing the separation coefficient is stopped. The hydrogen isotope separation system according to claim 2.

4. The anode supply path is provided with an electrolytic device for electrolyzing heavy water containing light water, The control device is If the supply-side concentration ratio at system startup is below the predetermined value, control is executed to increase the separation coefficient. A hydrogen isotope separation system according to any one of claims 1 to 3.

5. The control device is The separation coefficient is increased by performing at least one of the following: applying current to the separator, increasing the humidity of the fluid supplied to the anode, increasing the humidity of the fluid supplied to the cathode, decreasing the flow rate of the fluid supplied to the anode, and increasing the flow rate of the fluid supplied to the cathode. The hydrogen isotope separation system according to claim 4.

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