JPH05232293A - Treating equipment of tritium - Google Patents

Abstract

PURPOSE:To enable easy and safe treatment of tritium by a method wherein the whole quantity of hydrogen isotope gas is oxidized, condensed-liquefied and stored. CONSTITUTION:An exhaust containing a hydrogen isotope mainly is introduced into an exhaust storage tank l and diluted with an inactive gas, while an oxygen gas being virtually in the same quantity as the hydrogen isotope is mixed therewith. The temperature of a mixed gas thus prepared is raised to a prescribed temperature by a heater 2 and introduced into a catalyst tower (oxidation accelerating means) 3. After the mixed gas is turned into water vapor and carbon dioxide and an inflammable is removed, cooling down near normal temperatures is made by a cooler 4 and the water vapor produced by oxidation in the catalyst tower 3 is passed through a dehumidifying tower 5 and removed. An exhaust gas from which humidity is removed is subjected to removal 6 and 7 of and particulates and led as an exhaust gas into an exhaust tube through a blower 8. Meanwhile, the dehumidifying tower 5 saturated by removal of the humidity is reactivated by heating by regenerating equipment for the dehumidifying tower. The humidity adsorbed by the dehumidifying tower 5 is vaporized and a reproduced gas obtained by the vaporization is cooled down and then collected and stored as drain in a storage tank for tritium and heavy water.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nuclear fusion reactor facility and its related equipment, or a related experimental equipment of the nuclear fusion reactor facility, in which a fuel containing hydrogen isotope gas as a main component is used as a fuel or a gas for core plasma. The present invention relates to a tritium treatment device that safely treats exhaust gas and exhaust gas from a neutral particle heating device.

[0002]

2. Description of the Related Art A nuclear fusion reactor has not been put to practical use until now, and is in the process of progressing from the stage of large-scale equipment for critical plasma test to the stage of the next experimental reactor. The most feasible combination currently available for plasma fusion gas is deuterium (D) and tritium (T: tritium).
Of about 50% each.

Since the above-mentioned tritium is radioactive and hardly exists in nature, experiments have been conducted with deuterium (D) or normal hydrogen (H: light hydrogen) up to the current critical experimental device. Further, the fuel gas injected into the core generates plasma, is then evacuated, and is directly discharged to the atmosphere.

However, when tritium is used as the gas for plasma, the plasma exhaust cannot be directly discharged to the atmosphere because tritium has a radioactive property. Therefore, future deuterium (D) and tritium (T)
In an experimental reactor that mixes with hydrogen, impurities are removed from the fuel exhaust, deuterium (D), tritium (T), or mixed hydrogen (H) isotope separated, and hydrogen (H) is released into the atmosphere and deuterium ( D) and tritium (T) are considered to be stored for reuse. Since the storage method in this case enables reuse, it is necessary that there is almost no mixture of impurities.

In this experimental reactor, an isotope separation device for hydrogen isotope gas plays an important role, and a powerful method for the isotope separation device is to cool it with ultra-low temperature helium to distill the isotope of liquefied hydrogen gas. There are a cryogenic distillation method for separation, a thermal diffusion method for isotopically separating hydrogen gas by thermal diffusion of a central heating wire and an external cooling method. However, the former cryogenic distillation method requires a certain amount of treatment constantly and needs to be continuously supplied, and temperature adjustment is not easy. The latter thermal diffusion method requires a large number of cascades even if the throughput is small, and requires a large space.

Therefore, in the design of experimental equipment and experimental furnaces up to now, such a tritium removing apparatus is not installed like a critical apparatus at all, or a full-scale isotope separation apparatus is installed like an experimental furnace. It was either.

[0007]

By the way, although deuterium is mainly used for the experiment in the generation equipment in the process of shifting from the critical experimental equipment to the experimental reactor, in such an experiment deuterium (D) and deuterium are used. Hydrogen (D) slightly reacts with each other to generate tritium T. Although the amount generated is somewhat resistant to being released into the atmosphere as it is, the amount is too small to install full-scale processing equipment. Moreover, since the experiment is performed intermittently, there is not a certain amount of processing continuously.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a simple and safe tritium processing apparatus adapted to a core simulation experiment level reactor.

[0009]

In order to solve the above-mentioned problems, a tritium processing apparatus according to the present invention processes fuel exhaust containing hydrogen isotope gas as a main component and exhaust from a neutral particle heating apparatus. In the tritium processing apparatus, an oxidation promoting means for oxidizing all the hydrogen isotope gas, a condensing / liquefying means for condensing / liquefying the regenerated vapor processed by the oxidation promoting means, and a condensing / liquefying means. And a storage means for collecting and storing the liquefied water.

[0010]

In the present invention having the above-mentioned structure, since the hydrogen isotope gas is completely oxidized in the exhaust gas from the fuel exhaust system and the exhaust gas from the neutral particle heating device, it is stored after being condensed / liquefied. It is not a full-scale facility like the experimental furnace design and is not reused even when stored, so a simple device can be used without considering the purity. Moreover, since the fuel exhaust is not directly emitted to the atmosphere, there is no pollution of the general environment.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of the tritium treatment apparatus according to the present invention. In this embodiment, the facility scale is such that the amount of exhaust gas is of the order of 1.5 m ³ / hr, in which tritium of about 1/10000 is contained. It is supposed to include.

In FIG. 1, the tritium processing apparatus has an exhaust gas storage tank 1 which is the first device of the main system, and in this exhaust gas storage tank 1, the core fuel plasma is a fuel vacuum exhaust system or a neutral particle injection heating device ( Hereinafter, it is exhausted by an exhaust system of NBI) and is introduced here. Further, the exhaust gas storage tank 1 sufficiently dilutes an inert gas for safety thereafter, and mixes oxygen gas for oxidizing exhaust gas with hydrogen isotope in substantially equal amounts. The adjusted mixed gas is heated to a predetermined temperature via the heater 2.

The heated mixed gas is introduced into a catalyst tower 3 as an oxidation promoting means, and the catalyst tower 3 passes hydrogen isotopes and hydrocarbons through a catalyst to convert them into steam and carbon dioxide, thereby converting combustible substances. Remove. Since the gas treated in the catalyst tower 3 has a high temperature, it is cooled to near room temperature by the cooler 4 in the next stage. Further, the water vapor generated by being oxidized in the catalyst tower 3 is adsorbed and removed through a dehumidification tower 5 filled with a desiccant such as a molecular sieve (molecular sieve: trade name).

Since the radioactive component is removed from the exhaust gas from which the moisture has been removed, fine powder of a desiccant such as molecular sieve is removed by the mesh filter 6, and this mesh
Fine particles that could not be removed by the filter 6 are removed through the high-performance filter 7. The exhaust residual gas from which the fine particles have been removed is guided to the exhaust stack by the blower 8. A silencer 9 is provided if it is necessary to take measures against the noise of the blower 8.

On the other hand, the dehumidification tower 5 is provided with a dehumidification tower regeneration equipment 10 as an accessory equipment.
The dehumidifying tower 5 is heated and regenerated by removing moisture, and when the inert gas heated to a predetermined operating temperature by the regeneration gas blower 11 is blown to the dehumidifying tower 5, the dehumidifying tower 5 is heated. Moisture adsorbed by is evaporated, and the evaporated regenerated gas is cooled and liquefied by the regenerated gas cooler 12 as a condensation / liquefaction means. The regenerated gas mesh filter 13 connected to the regenerated gas cooler 12 removes water droplets accompanying it, and the regenerated gas from which the water droplets have been removed is regenerated gas blower 11
And is heated by the regeneration gas heater 14. here,
The noise generated from the regenerated gas blower 13 is removed by the regenerated gas blower silencer 15.

The water liquefied in the regeneration gas cooler 12 is collected and stored as a drain in a tritium heavy water storage tank 16 which is a storage means, and the storage tank 16 is sealed by a lid 17 and stored in the storage tank 16. When the pressure becomes equal to or higher than a predetermined pressure, it escapes from the exhaust pipe 19 through the escape vent line 18.

Next, the operation of this embodiment will be described.

The fuel exhaust gas and the N gas exhausted from the core fuel plasma by the fuel vacuum exhaust system or the NBI exhaust system.
The BI exhaust gas is discharged and then stored in the exhaust gas storage tank 1.
First, the exhaust gas mainly containing hydrogen isotope is introduced into the exhaust gas storage tank 1 to sufficiently dilute the inert gas and mix the oxygen gas with the hydrogen isotope in substantially equal amounts. However, in addition to the method of performing this mixing step in the exhaust gas storage tank 1, a method of combining after exiting the tank is also conceivable. Since the exhaust gas from the exhaust gas storage tank 1 is passed through the catalyst tower 3 to cause a reaction such as oxidation, it is necessary to adjust the temperature of the gas in advance to a temperature suitable for the catalytic reaction. The temperature is raised to a predetermined temperature via 2.

After that, the mixed gas is introduced into the catalyst tower 3, and in the catalyst tower 3, combustible substances are removed by converting it into steam and carbon dioxide. Next, since the gas processed in the catalyst tower 3 has a high temperature, it is cooled in the cooler 4 to near normal temperature. Further, the water vapor generated in the catalyst tower 3 is condensed and separated in order to separate it from other components having a lower boiling point. Therefore, the water vapor generated by being oxidized in the catalyst tower 3 is adsorbed and removed through the dehumidification tower 5. The dehumidifying tower 5 is provided with a standby system, and when saturated, switches to the standby system and performs a regeneration operation. It is desirable that the dehumidifying tower 5 has two to three systems including a standby system.

Exhaust gas from which moisture has been removed is subjected to fine powder removal by a mesh filter 6, and this mesh filter 6
The particulates that could not be removed in step 1 are removed through the high performance filter 7, and the exhaust residual gas is guided to the exhaust stack through the blower 8.

On the other hand, the dehumidification tower 5 which has been saturated by removing moisture is heated and regenerated in the dehumidification tower regeneration equipment 10. The dehumidifying tower regenerating equipment 10 blows the inert gas heated to a predetermined operating temperature to the dehumidifying tower 5 with a regenerating gas blower 11 to regenerate it by heating. At this time, the moisture adsorbed by the dehumidification tower 5 is evaporated, and the regenerated gas thus evaporated is cooled by the regenerated gas cooler 12 and is collected and stored as a drain in the tritium heavy water storage tank 16.

Further, the regenerated gas mesh filter 13 removes the entrained water droplets, and the regenerated gas from which the water droplets have been removed is heated by the regenerated gas heater 14 through the regenerated gas blower 11. Therefore, the deuterium and tritium in the exhaust gas are completely oxidized and stored in the tritium heavy water storage tank 16 in the form of water.

As described above, according to the present embodiment, the size of the tritium heavy water storage tank 16 may be about 1 m ³ , which is compact as a whole. Therefore, a wide space such as a system having a heat diffusion tower system is not necessary, and since the experiment is performed intermittently, the disadvantage of the cryogenic distillation system is also eliminated.

In the above embodiment, the exhaust gas storage tank 1, the heater 2, the catalyst tower 3, the mesh filter 6, the high-performance filter 7, and the blower 8 are each equipped with auxiliary machines in the main system. A plurality of standby systems may be provided like the wet tower 5 and each may be equipped with an auxiliary machine.

[0026]

As described above, according to the tritium treatment apparatus of the present invention, the hydrogen isotope gas is completely oxidized in the exhaust gas from the fuel exhaust system and the exhaust gas from the neutral particle heating device, Since it is condensed and liquefied and stored, the tritium generated in the plasma container by the deuterium plasma reaction can be removed, and the amount released to the general environment can be reduced without affecting public safety. In addition, the tritium removed from the exhaust gas can be safely managed so as not to leak, and the combustible exhaust gas can be safely processed. Further, since the fuel exhaust is not directly emitted to the atmosphere, it is possible to prevent pollution of the general environment.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of a tritium processing apparatus according to the present invention.

FIG. 2 is a system diagram showing a dehumidifying tower regenerating facility provided in a tritium treatment device.

[Explanation of symbols]

 1 Exhaust Storage Tank 2 Heater 3 Catalyst Tower (Oxidation Accelerator) 4 Cooler 5 Dehumidification Tower 10 Dehumidification Tower Regeneration Facility 11 Regeneration Gas Blower 12 Regeneration Gas Cooler (Condensation / Liquefaction Means) 13 Regeneration Gas Mesh Filter 14 Regeneration Gas heater 15 Regenerated gas blower / silencer 16 Tritium heavy water storage tank (storage means)

Claims (1)

[Claims] 1. A tritium treatment device for treating fuel exhaust containing hydrogen isotope gas as a main component and exhaust from a neutral particle heating device, and an oxidation promoting means for promoting oxidation of all the hydrogen isotope gas. A condensing / liquefying means for condensing / liquefying the regenerated vapor treated by the oxidation promoting means, and a storage means for collecting and storing the water liquefied by the condensing / liquefying means. Tritium processing equipment.