A tritium tail gas rapid collection and processing device

Abstract

The present invention discloses a device for rapidly collecting and treating tritium tail gas, which converts tritium gas (HT) in tritium tail gas into (HTO) by a catalytic oxidation method, and then collects and condenses the tritium tail gas. The incompletely reacted tritium tail gas enters an ionization chamber for tritium concentration measurement, and is discharged after reaching the standard. If it does not reach the standard, it is returned for treatment again until it reaches the standard for discharge. The present invention realizes the rapid collection and treatment of tritium tail gas, and at the same time realizes the collection of tritium water, and greatly reduces the output of solid waste after the treatment of tritium exhaust gas, and reduces the environmental emission of tritium-containing exhaust gas. It has the characteristics of simple structure, rapid and efficient, safe and reliable, and is suitable for the rapid and effective treatment of complex tritium-containing tail gas generated in places such as nuclear power plants, tritium target production, neutron generator production, nuclear facility decommissioning and fusion energy research.

Description

Technical Field

[0001] The invention belongs to the technical field of radiation protection and environmental protection, and in particular relates to a device for quickly collecting and processing tritium tail gas. Background Art

[0002] Many nuclear facility workplaces produce waste gas containing highly radioactive tritium gas and tritiated water. Direct discharge of these tritium-containing waste gases will pollute the environment, and they must be purified so that the tritium content of the emissions reaches or is lower than the tritium emission standard to meet the requirements of environmental protection. At present, the tritium-containing waste gas generated in radioactive sites is mainly purified by a huge purification system and then discharged to the environment through a single chimney. The purification system mainly uses catalyst catalytic oxidation and molecular sieve dry adsorption to treat and absorb tritium-containing waste gas. The purification system has the disadvantages of generating a lot of waste, low efficiency, and high cost when treating tritium-containing waste gas. In addition, the direct purification system for the treatment of tritium-containing waste gas requires frequent replacement of purification materials, and the tritium index of the discharged waste gas is high, which is easy to cause safety hazards to operators and the environment.

[0003] In summary, there is an urgent need to develop a new type of tritium tail gas collection and treatment device to overcome the defects existing in the above-mentioned traditional tritium tail gas treatment method. Summary of the invention

[0004] The present invention aims to provide an efficient, rapid, safe and reliable tritium tail gas rapid collection and processing device.

[0005] To achieve this object, the present invention adopts the following technical solutions:

[0006] A device for rapidly collecting and treating tritium tail gas, characterized in that the device comprises a catalytic collection unit, which comprises a connecting pipe provided with a valve I, a catalytic oxidation bed, a cooler, and a tritium water collection tank, wherein the catalytic oxidation bed, the cooler, and the tritium water collection tank are connected in sequence.

[0007] Preferably, the catalytic collection unit is provided with a valve III and a storage and measurement unit which are sequentially connected to one side of the exhaust end of the cooler.

[0008] Preferably, the storage and measurement unit comprises an exhaust gas storage tank and an exhaust gas measurement unit which are connected in sequence.

[0009] Preferably, the storage and measurement unit further comprises a pump connected to one side of the air inlet end of the exhaust gas storage tank.

[0010] Preferably, the storage and measurement unit further comprises a pressure sensor connected to one side of the exhaust end of the exhaust gas storage tank.

[0011] Preferably, a valve IV is provided between the waste gas storage tank and the tail gas measurement unit, and a valve V and a valve VI are provided in sequence on one side of the exhaust end of the tail gas measurement unit.

[0012] Preferably, a valve II is provided on one side of the air inlet end of the storage and measurement unit.

[0013] Preferably, the connecting pipe is an EP grade stainless steel pipe.

[0014] Preferably, the catalytic oxidation bed is a room temperature catalytic oxidation bed for tritium, and contains a room temperature catalyst or a high temperature catalyst.

[0015] Preferably, the pump is a vacuum pump or a vacuum booster pump.

[0016] Preferably, the exhaust gas measurement unit is a tritium ionization chamber or a proportional counter.

[0017] Preferably, the cooler is a low temperature cold trap or a strong air convection chamber.

[0018] Preferably, the valve I, valve II, valve III, valve IV, valve V, and valve VI are pneumatic valves or manual valves.

[0019] The present invention realizes the catalytic oxidation of tritium gas (HT) by adopting a method of catalytic oxidation with a catalyst at room temperature, and realizes the collection of tritiated water (HTO) by adopting a condensation collection method. Compared with the traditional method of adsorbing HTO with a molecular sieve, the generation of tritium-containing solid waste is greatly reduced. At the same time, the collection of HTO reduces the content of HTO water vapor in gas emissions, greatly reduces the tritium concentration in the exhaust gas, and reduces the environmental emissions of tritium-containing exhaust gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of the tritium tail gas rapid collection and processing device of the present invention;

[0021] In the figure, 1. Valve I 2. Catalytic oxidation bed 3. Cooler 4. Tritium water collection tank 5. Valve III 6. Pump 7. Waste gas storage tank 8. Pressure sensor 9. Valve II 10. Valve IV 11. Exhaust gas measurement unit 12. Valve V 13. Valve VI DETAILED DESCRIPTION

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0023] The tritium tail gas rapid collection and treatment device of the present invention comprises a catalytic collection unit, which comprises a connecting pipe provided with a valve I1, a catalytic oxidation bed 2, a cooler 3, and a tritium water collection tank 4, wherein the catalytic oxidation bed 2, the cooler 3, and the tritium water collection tank 4 are connected in sequence. The device specifically performs tritium tail gas sampling by opening the valve 1, and finally collects the treated tritium water in the tritium water collection tank 4 by catalytic oxidation of the catalytic oxidation bed 2 and condensation treatment of the cooler 3. In the device, the catalytic oxidation bed converts HT in the tritium-containing exhaust gas into HTO by the principle of catalytic oxidation, thereby improving the HTO collection efficiency of the cooling part. The present invention applies cooling technology to the collection and treatment of tritium tail gas, greatly improving the HTO collection rate in the tritium-containing exhaust gas, avoiding the defect of generating a large amount of solid tritium-containing waste when the traditional molecular sieve collects HTO, and the collection efficiency of this invention can reach more than 99%, reducing the tritium intake of on-site operators in tritium-related operations, and greatly reducing the radiation hazard of radioactive gas to personnel.

[0024] The tritium tail gas rapid collection and treatment device of the present invention is a highly efficient small device integrating the catalytic oxidation of tritium gas (HT) and the collection of tritiated water (HTO). The tritium tail gas rapid treatment device is suitable for the rapid and effective treatment of complex tritium-containing tail gas generated in nuclear power plants, tritium target production, neutron generator production, nuclear facility decommissioning, fusion energy research and other places.

[0025] In a preferred embodiment, the catalytic collection unit is provided with a valve III5 and a storage and measurement unit which are sequentially connected to one side of the exhaust end of the cooler 3. The storage and measurement unit is introduced into the tritium tail gas collection and treatment device of the present invention to measure the tritium concentration in the tritium-containing tail gas in real time, so as to determine whether to perform secondary treatment of the tritium-containing tail gas or discharge it up to standard. The opening of the valve III5 allows the remaining gas that is not completely catalytically oxidized to enter the storage and measurement unit.

[0026] Furthermore, the storage and measurement unit comprises an exhaust gas storage tank 7 and an exhaust gas measurement unit 11 which are connected in sequence.

[0027] The present invention specifically collects the remaining gas that is not completely catalytically oxidized by the catalytic oxidation bed through the exhaust gas storage tank 7 and measures the concentration through the exhaust gas measurement unit 11.

[0028] Furthermore, in order to increase the collection speed of tritium tail gas, the storage and measurement unit further includes a pump 6 connected to one side of the air inlet end of the exhaust gas storage tank 7 .

[0029] Furthermore, the storage and measurement unit further includes a pressure sensor 8 connected to one side of the exhaust end of the exhaust gas storage tank 7 to monitor the gas pressure in the exhaust gas storage tank 7 in real time.

[0030] Furthermore, a valve IV10 is provided between the waste gas storage tank 7 and the tail gas measurement unit 11, and a valve V12 and a valve VI13 are provided in sequence on one side of the exhaust end of the tail gas measurement unit 11. The present invention controls the opening of the valve IV10 to allow the gas to flow from the waste gas storage tank 7 to the tail gas measurement unit 11; when the tritium concentration result of the tritium tail gas measured by the measurement unit 11 shows that it meets the emission standard, the valve V12 and the valve VI13 are opened for emission; when the tritium concentration result shows that it does not meet the emission standard, the valve V12 and the valve 1 are opened for secondary catalytic oxidation treatment until the emission meets the standard.

[0031] Furthermore, a valve II9 is ​​provided at one side of the air inlet end of the storage and measurement unit. The present invention can directly sample the tritium tail gas sample to be processed to measure the tritium concentration, and judge whether the tritium tail gas meets the standard through the tritium concentration value to decide whether to perform catalytic oxidation treatment.

[0032] Furthermore, the connecting pipe is an EP grade stainless steel pipe.

[0033] Furthermore, the catalytic oxidation bed 2 is filled with a room temperature catalyst or a high temperature catalyst to carry out room temperature catalytic oxidation of tritium or high temperature catalytic oxidation treatment of the tritium tail gas.

[0034] Furthermore, the pump 6 is a vacuum pump or a vacuum booster pump.

[0035] Furthermore, the exhaust gas measurement unit 11 is a tritium ionization chamber or a proportional counter.

[0036] Furthermore, the cooler 3 is a low temperature cold trap or a strong air convection chamber.

[0037] Furthermore, the valve I1, valve II9, valve III5, valve IV10, valve V12, and valve VI13 are pneumatic valves or manual valves.

[0038] The present invention provides an efficient, rapid, safe and reliable tritium tail gas treatment device, which reduces the tritium concentration in the exhaust gas and reduces the solid waste content in the process of treating the tritium-containing exhaust gas.

[0039] The present invention is not limited to the above-mentioned specific implementation modes. Various changes made by technicians in the relevant technical field based on the above-mentioned conception without creative work all fall within the protection scope of the present invention.

[0040] Example 1

[0041] Open valve II, turn on the pump, and draw the tritium-containing exhaust gas generated by a tritium-related operation from the connecting pipe to the exhaust gas storage tank. Then open valve IV and turn on the exhaust gas measurement unit to measure the tritium concentration in the exhaust gas. The results show that the tritium concentration exceeds the standard and requires further treatment. Open valve V, valve I, and the catalytic oxidation bed in turn to carry out catalytic oxidation treatment of the exhaust gas. Then, open the cooler and the tritium water collection tank to collect the oxidized HTO. After the HTO collection is completed, open valve III, the pump, the exhaust gas storage tank, valve IV, and the exhaust gas measurement unit in turn to measure the tritium concentration. The detection value shows that the tritium concentration value is 5.4×10 5 Bq / L, which is lower than the emission standard and is discharged directly into the atmosphere.

[0042] The pump in this embodiment is a vacuum booster pump;

[0043] The cooler in this embodiment is a strong air convection chamber;

[0044] The valve I1, valve II9, valve III5, valve IV10, valve V12 and valve VI13 in this embodiment are all manual valves.

Claims

1. A tritium tail gas rapid collection and processing device, characterized in that: The tritium tail gas rapid processing device comprises a catalytic collection unit, which comprises a connecting pipe provided with a valve I (1), a catalytic oxidation bed (2), a cooler (3), and a tritium water collection tank (4), wherein the catalytic oxidation bed (2), the cooler (3), and the tritium water collection tank (4) are connected in sequence; The catalytic collection unit is provided with a valve III (5) and a storage and measurement unit which are sequentially connected to one side of the exhaust end of the cooler (3); The storage and measurement unit comprises an exhaust gas storage tank (7) and an exhaust gas measurement unit (11) which are connected in sequence; The storage and measurement unit further comprises a pump (6) connected to one side of the air inlet end of the exhaust gas storage tank (7); The storage and measurement unit further comprises a pressure sensor (8) connected to one side of the exhaust end of the exhaust gas storage tank (7); A valve IV (10) is provided between the exhaust gas storage tank (7) and the exhaust gas measurement unit (11), and a valve V (12) and a valve VI (13) are provided in sequence on one side of the exhaust end of the exhaust gas measurement unit (11); A valve II (9) is provided on one side of the air inlet end of the storage and measurement unit.

2. The tritium tail gas rapid collection and processing device according to claim 1 is characterized in that: The connecting pipe is an EP grade stainless steel pipe.

3. The tritium tail gas rapid collection and processing device according to claim 1 is characterized in that: The catalytic oxidation bed (2) contains a room temperature catalyst or a high temperature catalyst.

4. The tritium tail gas rapid collection and processing device according to claim 1 is characterized in that: The pump (6) is a vacuum pump or a vacuum booster pump.

5. The tritium tail gas rapid collection and processing device according to claim 1 is characterized in that: The tail gas measurement unit (11) is a tritium ionization chamber or a proportional counter.

6. The tritium tail gas rapid collection and processing device according to claim 1 is characterized in that: The cooler (3) is a low-temperature cold trap or a strong air convection chamber.

7. The tritium tail gas rapid collection and processing device according to claim 1 is characterized in that: The valve I (1), valve II (9), valve III (5), valve IV (10), valve V (12), and valve VI (13) are pneumatic valves or manual valves.

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