An air tritium-carbon sampler with strong environmental adaptability

Abstract

The present invention provides a tritium-carbon sampler in air with strong environmental adaptability, which includes a sampling gas path, a cooling branch and a heating branch. The sampling gas path is used to transport the gas to be measured and collect substances containing tritium and carbon-14 nuclides. The cooling branch is used to cool the gas to be measured and the solution in the collection bottle. The heating branch heats the coolant when the ambient temperature is lower than 0°C to prevent the solution from freezing. The present invention introduces a primary-effect condenser tube and a condensation bottle to condense the extracted gas, effectively preventing the risk that the first collection bottle will be filled with condensed water. At the same time, the condensed water is regularly pumped away by a water pump, enabling the sampler to meet the requirements of long-term sampling in a high-humidity environment. By setting up the heating branch, the sampler can sample in a low-temperature environment without additional cost investment such as an air-conditioned room or an air-conditioned cabinet, greatly increasing the applicability of the sampler under low-temperature conditions.

Description

Technical Field

[0001] The present invention belongs to the technical field of tritium and carbon nuclide sampling, and particularly relates to an air tritium and carbon sampler with strong environmental adaptability. Background Art

[0002] Nuclear facilities such as nuclear power plants will generate substances containing two radioactive nuclides, 3H and 14C, in different forms. These substances will cause varying degrees of pollution to the environment and pose hazards to the human body. In view of the requirements of the development of national nuclear power technology and the uncertainties of international nuclear radiation safety, it is urgent to strengthen the monitoring construction, strengthen the capacity building of radiation environmental quality, and strengthen the emergency response capacity building. At present, the collection equipment for these two nuclides mostly adopts the bubbling method design, that is, the air flow to be measured is passed through a bubbler, so that tritium or carbon-14 in the air is collected into the corresponding solvent. This method is simple and efficient, so it is widely used in the market. However, the existing sampling equipment on the market cannot meet some complex working conditions due to design problems, mainly manifested in that it cannot be used alone in high-humidity and low-temperature environments and outdoor sub-zero environments, and special air-conditioning cabinets or station houses need to be equipped, and the use of the equipment has great limitations. Summary of the Invention

[0003] In view of the technical problem that the existing tritium and carbon nuclide sampling equipment cannot be used in high-humidity and sub-zero temperature environments, the present invention provides an air tritium and carbon sampler with strong environmental adaptability for a refrigeration and heating pipeline.

[0004] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] An air tritium and carbon sampler with strong environmental adaptability includes a sampling gas path, a cooling branch, and a heating branch. The sampling gas path includes a primary condensation tube, a condensation bottle, a temperature and humidity sensor, a first collection bottle, a second collection bottle, a catalytic furnace, a third collection bottle, and a fourth collection bottle, which are sequentially connected by an air pipe;

[0006] The primary condensation tube includes an inner tube and an outer tube. Spiral refrigeration tubes are installed in all four collection bottles. The catalytic furnace includes a catalytic tube filled with a catalyst and a heating device. A coolant heat exchange tube is arranged at the bottom of the heating device; the cooling branch includes a water tank and water pump integrated machine filled with coolant. The water tank and water pump integrated machine includes a first water outlet, a first water return port, a second water outlet, and a second water return port. The first water outlet is sequentially connected to a heat exchanger, the spiral refrigeration tubes of the four collection bottles, the outer tube of the primary condensation tube, and the first water return port through a water pipe;

[0007] The heating branch includes a second water outlet, a coolant heat exchange tube, a coolant circulation pump, and a second water return port, which are sequentially connected by a water pipe.

[0008] Preferably, an anti-backflow air path is further included. The anti-backflow air path includes a first two-way electromagnetic valve connected between the first collection bottle and the second collection bottle, and a second two-way electromagnetic valve connected between the third collection bottle and the fourth collection bottle. The other ends of the two two-way electromagnetic valves are connected to the atmosphere.

[0009] Preferably, the catalytic tube includes a catalytic inner tube and a catalytic outer tube. The inner tube communicates with the catalytic tube air inlet, and side holes are provided on the side wall of the inner tube. The outer tube communicates with the catalytic tube air outlet.

[0010] Preferably, filter meshes are provided at the tops of both the catalytic inner tube and the catalytic outer tube.

[0011] Preferably, a drainage pump is connected to the condensation bottle.

[0012] Preferably, after the fourth collection bottle, a drying cylinder, a one-way valve, a flow meter, and an air extraction pump are connected via an air pipe.

[0013] Preferably, a fixing plate is further included. Four collection bottle fixing members are provided on the fixing plate, and the collection bottles are screwed onto the collection bottle fixing members.

[0014] Preferably, sealing members are provided between the fixing plate and the collection bottle fixing members, and between the collection bottle fixing members and the collection bottles.

[0015] Preferably, a water receiving plate is further included and installed below the four collection bottles.

[0016] Preferably, foaming devices are provided in all four collection bottles. The foaming device includes an air inlet pipe and a foaming member connected to the lower end of the air inlet pipe. The foaming member is of a hollow structure, and upper and lower layers of air outlet holes are provided on the side wall of the foaming member.

[0017] Compared with the prior art, the advantages and positive effects of the present invention are as follows:

[0018] 1. The tritium carbon sampler in the air of the present invention introduces a primary effect condensation tube and a condensation bottle to condense the extracted gas, effectively preventing the risk that the first collection bottle will be filled with condensed water. At the same time, the condensed water is regularly pumped away by a water extraction pump, enabling the sampler to meet the requirements of long-term sampling in a high-humidity environment.

[0019] 2. A heating branch is provided to heat up the coolant using the waste heat of the catalytic furnace, without generating additional power consumption. Then, the heated coolant is used to heat the solution in the collection bottle, so that it will not solidify even at 0°C. The sampler can sample in a low-temperature environment without additional cost investment such as an air-conditioned room or an air-conditioned cabinet, and can still operate under the condition of minus 10°C, greatly increasing the applicability of the sampler under low-temperature conditions.

[0020] 3. Set up an anti-backflow air path to effectively prevent the solution from flowing back and avoid liquid backflow during shutdown, which may affect the test results and damage the device.

[0021] 4. Adopt a stainless-steel cavity porous foam part, which can better play the role of bubbling, with a large amount of foaming, small foaming pore diameter, high solution absorption rate, and low instrument load.

[0022] 5. The catalytic tube is small and compact, and the catalyst is filled in both the inner and outer tubes. When the overall length of the catalytic furnace is fixed, the gas passing through the catalytic furnace has a doubled path, ensuring sufficient catalytic oxidation time. Description of the Drawings

[0023] Figure 1 It is the schematic diagram of the pipeline connection of the tritium carbon sampler in the air of the present invention;

[0024] Figure 2 It is the schematic diagram of the internal structure of the tritium carbon sampler in the air of the present invention;

[0025] Figure 3 It is the schematic diagram of the structure of the tritium carbon sampler in the air of the present invention;

[0026] Figure 4 It is the cross-sectional view of the primary effect condensation tube of the tritium carbon sampler in the air of the present invention;

[0027] Figure 5 It is the cross-sectional view of the catalytic tube of the tritium carbon sampler in the air of the present invention;

[0028] Figure 6 It is the schematic diagram of the structure of the collection module of the tritium carbon sampler in the air of the present invention;

[0029] Figure 7 It is the cross-sectional view of the collection module of the tritium carbon sampler in the air of the present invention;

[0030] Figure 8 It is another cross-sectional view of the collection module of the tritium carbon sampler in the air of the present invention;

[0031] Figure 9 It is the schematic diagram of the structure of the foam part of the tritium carbon sampler in the air of the present invention;

[0032] In the above figures: 1. Intake port; 2. Primary condensation tube; 3. Inner tube; 4. Outer tube; 5. Condensation bottle; 6. Drainage pump; 7. Temperature and humidity sensor; 8. First collection bottle; 9. Second collection bottle; 10. Spiral refrigeration tube; 11. Inlet pipe; 12. Foaming part; 13. Air outlet hole; 14. Catalytic furnace; 15. Catalytic tube; 16. Heating device; 17. Catalytic outer tube; 18. Catalytic inner tube; 19. Side hole; 20. Filter screen; 21. First one-way valve; 22. Third collection bottle; 23. Fourth collection bottle; 24. Drying cylinder; 25. Filter; 26. Temperature sensor; 27. Flowmeter; 28. Air capacitance; 29. Exhaust port; 30. Integrated water tank and water pump; 31. Heat exchanger; 32. Heat exchange tube; 33. Refrigerator; 34. Coolant circulation pump; 35. First two-way solenoid valve; 36. Second two-way solenoid valve; 37. Collection bottle fixing plate; 38. Collection bottle fixing part; 39. Sealing gasket; 40. Water receiving plate; 41. Air extraction pump; 42. O-ring. Detailed implementation manner

[0033] To better understand the present invention, specific descriptions will be made below in conjunction with the drawings and embodiments.

[0034] Embodiment: As Figures 1 - 3 shown, a tritium-carbon sampler in the air with strong environmental adaptability includes a sampling gas path, a cooling branch, and a heating branch. The sampling gas path is used to transport the gas to be measured and collect substances containing tritium and carbon-14 nuclides. The cooling branch is used to cool the gas to be measured and the solution in the collection bottle. The heating branch heats the coolant when the environmental temperature is lower than 0°C to prevent the solution from freezing.

[0035] The sampling gas path includes an intake port 1. The intake port 1 is sequentially connected to a primary condensation tube 2, a condensation bottle 5, a temperature and humidity sensor 7, a first collection bottle 8, a second collection bottle 9, a catalytic furnace 14, a first one-way valve 21, a third collection bottle 22, a fourth collection bottle 23, a drying cylinder 24, a filter 25, a temperature sensor 26, a flowmeter 27, an air capacitance 28, and an air extraction pump 41 through a trachea. The air outlet end of the air extraction pump 41 is connected to an exhaust port 29 to discharge the gas. The first one-way valve 21 can prevent the air flow from flowing back and avoid affecting the experimental results. The drying cylinder 24 can remove the moisture in the air flow, the filter 25 can filter the impurities in the gas, the temperature sensor 26 is installed near the flowmeter 27 to detect the gas temperature here, and an air capacitance 28 is arranged downstream of the flowmeter 27 to make the air flow stable. The four cooperate to ensure that the flowmeter 27 accurately detects the gas flow rate, thereby accurately measuring the volume of the sampled gas and improving the accuracy of the sampling device.

[0036] The primary condensation tube 2 can preliminarily cool the sampling gas, such as Figure 4As shown, its structure includes an inner tube 3 and an outer tube 4 sleeved on the outer layer of the inner tube 3. The inner tube 3 is used to accommodate the gas to be measured flowing in through the air inlet 1; the outer tube 4 is provided with an inlet and an outlet, and the outer tube 4 is used to accommodate the coolant. Preferably, the inner diameter of the inner tube 3 is 2-5 times the inner diameter of the gas pipe. The increase in the volume of the inner tube 3 can be used as an air capacitance to stabilize the air flow and can increase the residence time of the gas in the inner tube 3, increasing the cooling effect. The downstream of the primary condensation tube 2 is connected to a condensation bottle 5, and the condensation bottle 5 cools and reduces the temperature of the gas to be measured again. The double cooling measures can effectively remove the water vapor carried in the gas and effectively prevent the risk that the first collection bottle 8 will be filled with condensed water. In a high-humidity environment, the collection bottle will be quickly filled with water, which is also the main reason why the existing equipment on the market cannot sample for a long time in a high-humidity environment.

[0037] At the same time, a drainage pump 6 is connected to the condensation bottle 5, and the drainage pump 6 timely pumps away the condensed water, enabling the sampler to meet the requirements of long-term sampling in a high-humidity environment.

[0038] Spiral refrigeration tubes 10 are installed in all four collection bottles. The catalytic furnace 14 includes a catalytic tube 15 filled with a catalyst and a heating device 16. A coolant heat exchange tube is arranged at the bottom of the heating device 16. The cooling branch includes a water tank water pump integrated machine 30 filled with coolant. The water tank water pump integrated machine 30 includes a first water outlet, a first water return port, a second water outlet, and a second water return port. The first water outlet is connected to the heat exchanger 31, the spiral refrigeration tubes 10 of the four collection bottles, the outer tube 4 of the primary condensation tube 2, and the first water return port in sequence through a water pipe to form a circulation loop. The heat exchanger 31 includes a heat exchange tube 32 and a refrigerator 33 that provides a cold source for the heat exchange tube 32. The gas after condensation enters the first collection bottle 8 and the second collection bottle 9. Different solvents can be placed in the two collection bottles to absorb different gases. When collecting 14 CO2, NaOH solutions are filled in both the first collection bottle 8 and the second collection bottle 9. When collecting tritiated water, distilled water is filled in both the first collection bottle 8 and the second collection bottle 9. Then the gas undergoes high-temperature catalysis in the catalytic furnace 14. The catalytic furnace 14 can oxidize gases such as CO and CH4 into CO2, and oxidize hydrogen and CH4 into tritiated water. The catalyzed gas is then completely absorbed by the third collection bottle 22 and the fourth collection bottle 23. Similarly, when collecting 14 CO2, NaOH solutions are filled in both the third collection bottle 22 and the fourth collection bottle 23. When collecting tritiated water, distilled water is filled in both the third collection bottle 22 and the fourth collection bottle 23. The cooling branch can keep the temperature of the solution in the collection bottle at 5-8 °C, preventing the solution in the collection bottle from being vaporized and pumped away due to too high a temperature, resulting in errors in test data.

[0039] Such as Figure 5As shown, the catalytic tube 15 of the catalytic furnace 14 includes a catalytic outer tube 17 and a catalytic inner tube 18. The upper end of the catalytic outer tube 17 is connected to the catalytic tube air inlet, and a plurality of side holes 19 are arranged on the side wall of the lower end of the inner tube. The upper end of the catalytic inner tube 18 is connected to the catalytic tube air outlet. The catalytic outer tube 17 and the catalytic inner tube 18 are both filled with alumina-supported platinum or alumina-supported palladium catalysts. The heating device 16 includes a heating wire for high-temperature heating of the catalytic tube, which can oxidize gases such as CO and CH4 into CO2, and oxidize gases such as hydrogen and CH4 into tritiated water. The inside of the catalytic outer tube 17 and the catalytic inner tube 18 are both filled with catalysts. When the overall length of the catalytic furnace 14 is constant, the distance of the gas passing through the catalytic furnace 14 is doubled, ensuring sufficient catalytic oxidation time. The tops of the catalytic outer tube 17 and the catalytic inner tube 18 are both provided with filter screens 20 to prevent the catalyst from being carried out by the airflow.

[0040] The heating branch includes a second water outlet, a coolant heat exchange tube, a coolant circulation pump 34 and a second water return port which are connected in sequence through a water pipe. When the ambient temperature is lower than 0°C, the heating branch starts to operate, and the coolant circulation pump 34 transports the coolant in the water tank and water pump integrated machine 30 to the coolant heat exchange tube of the catalytic furnace 14. Since the temperature in the catalytic furnace 14 is above 400°C, the surface temperature is about 60°C-100°C after adding the heat insulation device, which can just heat the coolant in the coolant heat exchange tube, and make full use of the waste heat of the catalytic furnace 14 to heat the coolant. The heated coolant flows into the spiral refrigeration tube 10 in the four collection bottles, so that the solution in the collection bottle can be heated, effectively preventing the solution from solidifying, and at the same time, no additional power consumption is generated, which greatly increases the applicability of the sampler under low temperature conditions.

[0041] In order to prevent the solution from flowing back and being sucked back due to the pressure difference in the four collection bottles, the tritium carbon sampler described in this embodiment is provided with an anti-backflow gas circuit. The anti-backflow gas circuit includes a first two-way solenoid valve 35 connected between the first collection bottle 8 and the second collection bottle 9, and a second two-way solenoid valve 36 connected between the third collection bottle 22 and the fourth collection bottle 23, and the other ends of the two two-way solenoid valves are connected to the atmosphere. Both two-way solenoid valves are normally closed solenoid valves. When the sampling is completed and the vacuum pump 41 is closed, the two solenoid valves are opened to connect the gas circuit to the atmosphere, which can effectively prevent the solution from flowing back.

[0042] To facilitate the replacement of the collection bottle, Figures 6 - 8 As shown, the tritium carbon sampler described in this embodiment also includes a collecting bottle fixing plate 37, on which four collecting bottle fixing parts 38 are arranged, and the collecting bottles are screwed on the collecting bottle fixing parts 38 by threads to form a collecting module. An O-ring 42 is arranged between the fixing plate 37 and the collecting bottle fixing parts 38, and a sealing gasket 39 is arranged between the collecting bottle fixing parts 38 and the collecting bottle to ensure a good sealing of the gas path. A water receiving plate 40 is installed under the four collecting bottles to receive the liquid dripping from the four collecting bottles.

[0043] To enable the solution in the collection bottle to fully absorb the gas, a foaming device is provided in each of the four collection bottles. The foaming device includes an air inlet pipe 11 and a foaming member 12 connected to the lower end of the air inlet pipe 11.

[0044] The foaming member 12 can be of three types: a PTFE material part, a stainless steel sintered filter element, and a stainless steel cavity porous foaming member 12. In this embodiment, a cavity porous foaming member 12 made of stainless steel or PTFE material is used, and its specific structure is as Figure 9 shown. It is hollow inside, and there are two upper and lower layers of air outlet holes 13 provided on the side wall. Compared with the foaming devices on the market, this foaming member has more foaming holes, smaller pore diameters, and uniform foaming, which can improve the solution absorption rate; compared with the stainless steel sintered filter element, it can reduce the instrument load.

[0045] The tritium carbon sampler for air in this embodiment introduces a primary efficient condensing tube 2 and a condensing bottle 5 to condense the extracted gas, effectively preventing the risk that the first collection bottle 8 will be filled with condensed water. At the same time, the condensed water is regularly pumped away by a water pump, enabling the sampler to meet the requirements of long-term sampling in a high-humidity environment.

[0046] A heating branch is set up to use the waste heat of the catalytic furnace 14 to heat up the coolant. Then, the heated coolant is used to heat the solution in the collection bottle so that it will not solidify even at 0 °C. Without the need to invest in additional costs such as an air-conditioned room or an air-conditioned cabinet, the sampler can sample in a low-temperature environment and can still operate under the condition of -10 °C, greatly increasing the applicability of the sampler under low-temperature conditions.

[0047] The above is only a preferred embodiment of the present invention, and it is not a limitation of the present invention in other forms. Any person skilled in the art may use the disclosed technical content to make changes or modifications into equivalent embodiments with equivalent changes and apply them to other fields. However, as long as it does not depart from the technical solution content of the present invention, any simple modification, equivalent change, and modification made to the above embodiments based on the technical essence of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. An air tritium-carbon sampler with strong environmental adaptability, characterized in that: It includes a sampling gas path, a cooling branch and a heating branch. The sampling gas path includes a primary condensation tube, a condensation bottle, a temperature and humidity sensor, a first collection bottle, a second collection bottle, a catalytic furnace, a third collection bottle and a fourth collection bottle that are sequentially connected via a gas pipe. The primary condensation tube includes an inner tube and an outer tube. Spiral refrigeration tubes are installed in all four collection bottles. The catalytic furnace includes a catalytic tube filled with a catalyst and a heating device. A coolant heat exchange tube is provided at the bottom of the heating device. The cooling branch includes a water tank and water pump integrated machine filled with coolant. The water tank and water pump integrated machine includes a first water outlet, a first water return port, a second water outlet and a second water return port. The first water outlet is sequentially connected to a heat exchanger, the spiral refrigeration tubes of the four collection bottles, the outer tube of the primary condensation tube and the first water return port via a water pipe. The heating branch includes a second water outlet, a coolant heat exchange tube, a coolant circulation pump and a second water return port that are sequentially connected via a water pipe. The catalytic tube includes a catalytic inner tube and a catalytic outer tube. The inner tube communicates with the catalytic tube inlet. Side holes are provided on the side wall of the inner tube. The outer tube communicates with the catalytic tube outlet. Filter meshes are provided at the tops of both the catalytic inner tube and the catalytic outer tube. Foaming devices are provided in all four collection bottles. The foaming device includes an air inlet pipe and a foaming member connected to the lower end of the air inlet pipe. The foaming member is of a hollow structure, and upper and lower layers of air outlet holes are provided on the side wall of the foaming member.

2. The air tritium and carbon sampler with strong environmental adaptability according to claim 1, wherein: It also includes an anti-backflow gas path. The anti-backflow gas path includes a first two-way solenoid valve connected between the first collection bottle and the second collection bottle, and a second two-way solenoid valve connected between the third collection bottle and the fourth collection bottle. The other ends of the two two-way solenoid valves are connected to the atmosphere.

3. The tritium carbon sampler in air with strong environmental adaptability according to claim 1, wherein: A drainage pump is connected to the condensation bottle.

4. The air tritium carbon sampler with strong environmental adaptability according to claim 1, characterized in that: After the fourth collection bottle, a drying cylinder, a one-way valve and a flow meter are connected via a gas pipe.

5. The tritium carbon sampler in air with strong environmental adaptability according to claim 1, wherein: It also includes a fixing plate. Four collection bottle fixing members are provided on the fixing plate. The collection bottles are screwed onto the collection bottle fixing members.

6. The air tritium carbon sampler with strong environmental adaptability according to claim 5, characterized in that: Sealing members are provided between the fixing plate and the collection bottle fixing members, and between the collection bottle fixing members and the collection bottles.

7. The air tritium carbon sampler with strong environmental adaptability according to claim 5, characterized in that: It also includes a water receiving plate installed below the four collection bottles.

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