A tritium measuring device with radon compensation function

Abstract

The present invention relates to the field of nuclear radiation detection technology, and provides a tritium measurement device with a radon compensation function. The device comprises a measurement unit, a pulse amplification circuit, a current amplification circuit, and a signal processing and display unit. The measurement unit has two paths: one path is connected to the pulse amplification circuit to measure radon pulse signals, thereby achieving radon compensation measurement; the other path is connected to the current amplification circuit to measure current signals including tritium and radon. The device utilizes the pulse signals generated by radon for compensation measurement, thereby avoiding the influence of tritium signals on radon measurement. It does not require detritium treatment and does not have complex drying and oxidation structures. It is easy to implement, simple, and efficient.

Description

Technical Field

[0001] The present invention relates to the technical field of nuclear radiation detection, in particular to a tritium measuring device with a radon compensation function. Background Art

[0002] Tritium is an isotope of hydrogen, typically existing in gaseous form (HT or T2) and as an oxide (HTO or T2O). It is a low-energy beta radionuclide, with a maximum beta particle energy of 18.6 keV. Excessive tritium concentration in the environment can pose a radiation hazard to personnel, necessitating real-time measurement of tritium concentration in the air to ensure personnel safety. Tritium beta particles have a maximum range of 5 mm in air, making them difficult to detect with conventional beta detectors. Instead, a flow-type ionization chamber is typically used for measurement.

[0003] However, in some applications, radon gas may be present in the air and enter the ionization chamber along with the sampled air. Radon is a radioactive gas that decays and emits alpha particles with an energy of 5.49 MeV. These alpha particles also ionize within the ionization chamber, interfering with tritium measurements. Therefore, it is necessary to identify and compensate for alpha particles of radon gas in the air.

[0004] The compensation principle is realized through two-way measurement. The tritium measurement channel measures the signal generated by both tritium and radon, while the radon compensation channel only measures the radon signal. The difference between the two measurement results is calculated to achieve compensation measurement of radon gas.

[0005] In order to remove the tritium signal, common radon compensation devices use two methods: one is to install a very thin film in the radon compensation device. Since the maximum energy of tritium beta particles is only 18.6keV, they cannot penetrate the film and thus cannot enter the radon compensation device. However, the energy of radon alpha particles is as high as 5.49MeV, which can penetrate the film and enter the radon compensation device, thereby generating a current signal in the radon compensation device. The magnitude of this current signal is related to the radon concentration, thereby realizing radon compensation measurement. However, due to the use of a thin film, this method will result in low radon detection efficiency, thereby reducing the sensitivity of radon measurement. At the same time, the mechanical strength of the film is low. Secondly, the gas to be measured is first subjected to tritium removal treatment before entering the radon compensation device. Tritium removal is divided into three steps. In the first step, the gas passes through a desiccant to remove tritiated water in the gas. In the second step, the gas passes through a high-temperature oxidation device to oxidize tritiated hydrogen and tritiated methane in the gas to oxidize them into tritiated water. In the third step, the gas passes through a desiccant again to remove tritiated water. After these three steps, the gas in the radon compensation device is free of tritium particles, and its output signal is a current signal generated by radon particles, thereby realizing radon compensation measurement. This method has an additional tritium removal system, which not only includes a desiccant that needs to be replaced regularly, but also a high-temperature and high-power consumption oxidation device, making the system inconvenient to use and maintain. Summary of the Invention

[0006] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a tritium measurement device with radon compensation function. The structure is easy to implement and can measure radon gas alpha particles in the test environment in real time. It has higher detection efficiency and sensitivity, and the equipment has higher mechanical strength.

[0007] The objective of the present invention is achieved through the following technical measures: a tritium measuring device with radon compensation function, comprising a measuring unit, a pulse amplifying circuit, a current amplifying circuit, and a signal processing and display unit. The measuring unit has two paths, one of which is connected to the pulse amplifying circuit to measure the pulse signal of radon to achieve radon compensation measurement, and the other is connected to the current amplifying circuit to measure the current signal including tritium and radon.

[0008] In this technical solution, the measurement unit includes two chambers. The collector of one chamber is connected to a pulse amplification circuit to measure the pulse signal generated by radon alpha particles. Since tritium β particles have low energy, the influence of tritium particles can be removed by setting a threshold, and the radon activity concentration in the gas to be measured can be obtained by the pulse counting rate; the collector of the other chamber is connected to a current amplification circuit to amplify and measure the current signal in the gas flow ionization chamber. The measurement signal contains the current signals of tritium β particles and radon alpha particles. The pulse counting rate of the radon signal is used to correct the current signal, which can achieve radon compensation for tritium measurement.

[0009] In this technical solution, the measuring unit is a series structure, including chamber A and chamber B. The gas to be measured enters chamber A from the air inlet, then enters chamber B from the air vent, and is finally discharged from the air outlet. Both chamber A and chamber B contain flat-plate high-voltage electrodes and collecting electrodes. The collecting electrode of chamber A is connected to a current amplifying circuit to measure the current signals of tritium and radon. The collecting electrode of chamber B is connected to a pulse amplifying circuit to measure the pulse signal of radon. The result of chamber A is corrected according to the measurement result of chamber B to complete the compensation of radon background.

[0010] In the present technical solution, the measuring unit is a parallel structure, including chamber A and chamber B. Both chamber A and chamber B include an air inlet and an air outlet. The gas to be measured enters the two chambers in parallel. Both chamber A and chamber B include a flat high-voltage electrode and a collecting electrode. The collecting electrode of chamber A is connected to a current amplifying circuit to measure the current signals of tritium and radon. The collecting electrode of chamber B is connected to a pulse amplifying circuit to measure the pulse signal of radon. The result of chamber A is corrected according to the measurement result of chamber B to complete the compensation of radon background.

[0011] The compensation algorithm is as follows:

[0012] Chamber A can be calibrated to obtain the conversion coefficient for tritium measurement: C:\Users\Administrator\AppData\Roaming\Tencent\Users\70533132\QQ\WinTemp\RichOle\OBL~1]PP@LZ3967%XI]6HLS.png , that is, the tritium concentration in the gas to be measured corresponding to the unit current output by chamber A;

[0013] Chamber A and Chamber B can be calibrated separately to obtain the conversion coefficient of radon concentration and , is the radon concentration in the gas to be measured corresponding to the unit current output by chamber A, is the radon concentration in the gas to be measured corresponding to the unit pulse count rate output by chamber B.

[0014] When the current measured in chamber A is The pulse count rate measured in chamber B is as follows: C:\Users\Administrator\AppData\Roaming\Tencent\Users\70533132\QQ\WinTemp\RichOle\8G_1XD$GPRJ2ES7@P87]Q`D.png , then the tritium concentration of the gas to be measured is: .

[0015] The tritium measurement device with radon compensation function adopts a novel radon compensation method, utilizing pulse signals generated by radon for compensation measurement, thereby avoiding the influence of tritium signals on radon measurement. This solution does not require tritium removal treatment and does not require complex drying and oxidation structures, making it easy to implement, simple, and efficient. Furthermore, the radon measurement chamber has a larger volume, resulting in higher radon detection efficiency and sensitivity, avoiding the use of thin films, and providing improved mechanical strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a structural diagram of a series tritium measurement device with radon compensation function.

[0017] Figure 2 This is a structural diagram of a parallel tritium measurement device with radon compensation function.

[0018] Figure 3 Schematic diagram of the structure of the series measurement unit.

[0019] Figure 4 This is a schematic diagram of the parallel measurement unit structure.

[0020] Among them: 1. Shell, 2. High voltage electrode, 3. Air inlet, 4. Air outlet, 5. Vent, 6. Collecting electrode of chamber A, 7. Collecting electrode of chamber B. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are intended only to illustrate the invention and are not intended to limit the invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0022] Example 1

[0023] like Figure 1 and Figure 3 As shown, this embodiment provides a tritium measuring device with a radon compensation function, which mainly includes a measuring unit, a pulse amplifying circuit, a current amplifying circuit, a signal processing and display unit, an electrical junction box, an air pump, a gas sampling port, a manual valve, a filter, a flow meter, a regulating valve, and a gas exhaust port. The gas sampling port is connected to the air inlet of the measuring unit via the manual valve and the filter, and the air outlet of the measuring unit is connected to the gas exhaust port via the flow meter, the regulating valve, and the air pump. The collector of chamber A in the measuring unit is connected to the current amplifying circuit, and the collector of chamber B is connected to the pulse amplifying circuit. The output ends of the current amplifying circuit and the pulse amplifying circuit are connected to the signal processing and display unit, and the signal processing and display unit is connected to the electrical junction box.

[0024] Figure 3 This is a schematic diagram of the tandem measurement unit structure. The gas to be measured enters chamber A through inlet 3, then enters chamber B through vent 5, and finally exits through outlet 4. Both chambers A and B contain a flat high-voltage electrode 2 and a collector. The difference is that the collector 6 in chamber A is connected to a current amplifier circuit to measure the current signals of tritium and radon, while the collector 7 in chamber B is connected to a pulse amplifier circuit to measure the pulse signal of radon. The measurement results of chamber A are corrected based on the measurement results of chamber B to compensate for the radon background. To reduce memory effects, the high-voltage electrode and collector can be made of wire-walled material.

[0025] Example 2

[0026] like Figure 2 and Figure 4As shown, this embodiment provides a tritium measuring device with a radon compensation function, which mainly includes a measuring unit, a pulse amplifying circuit, a current amplifying circuit, a signal processing and display unit, an electrical junction box, an air pump, a gas sampling port, a solenoid valve, a manual valve, a filter, a flow meter, a regulating valve, and a gas exhaust port. The gas sampling port is connected to the air inlets of chamber A and chamber B in the measuring unit via a manual valve, a filter, and two solenoid valves, respectively. The air outlets of chamber A and chamber B are connected to the gas exhaust port via a flow meter, a regulating valve, and an air pump. The collector of chamber A in the measuring unit is connected to the current amplifying circuit, and the collector of chamber B is connected to the pulse amplifying circuit. The output ends of the current amplifying circuit and the pulse amplifying circuit are connected to the signal processing and display unit, and the signal processing and display unit is connected to the electrical junction box.

[0027] Figure 4 This is a schematic diagram of the parallel measurement unit structure. Both chambers A and B include an inlet 3 and an outlet 4, allowing the gas to enter the two chambers in parallel. Each chamber contains a flat high-voltage electrode 2 and a collector. Similar to the series structure, the collector 6 of chamber A is connected to a current measurement circuit to measure the current signals of tritium and radon; the collector 7 of chamber B is connected to a pulse measurement circuit to measure the pulse signal of radon. The measurement results of chamber A are corrected based on the measurement results of chamber B to compensate for the radon background. To reduce memory effects, the high-voltage electrode and collector can be made of wire-walled material.

[0028] The contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0029] The above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A tritium measuring device with radon compensation function, characterized in that: The device includes a measuring unit, a pulse amplifying circuit, a current amplifying circuit, and a signal processing and display unit. The measuring unit has two paths, one of which is connected to the pulse amplifying circuit to measure the pulse signal of radon to achieve radon compensation measurement, and the other is connected to the current amplifying circuit to measure the current signal including tritium and radon.

2. The tritium measuring device with radon compensation function according to claim 1, characterized in that: The measuring unit is a series structure, including chamber A and chamber B. The gas to be measured enters chamber A from the air inlet, then enters chamber B from the air vent, and is finally discharged from the air outlet. Both chambers A and B contain flat high-voltage electrodes and collecting electrodes. The collecting electrode of chamber A is connected to a current amplification circuit to measure the current signals of tritium and radon. The collecting electrode of chamber B is connected to a pulse amplification circuit to measure the pulse signal of radon. The results of chamber A are corrected according to the measurement results of chamber B to complete the compensation of radon background.

3. The tritium measuring device with radon compensation function according to claim 1, wherein: The measuring unit is a parallel structure, including chamber A and chamber B. Both chamber A and chamber B include an air inlet and an air outlet. The gas to be measured enters the two chambers in parallel. Both chamber A and chamber B include a flat high-voltage electrode and a collecting electrode. The collecting electrode of chamber A is connected to a current amplification circuit to measure the current signals of tritium and radon. The collecting electrode of chamber B is connected to a pulse amplification circuit to measure the pulse signal of radon. The result of chamber A is corrected according to the measurement result of chamber B to complete the compensation of radon background.

4. The tritium measuring device with radon compensation function according to claim 2 or 3, characterized in that: The high voltage electrode and the collecting electrode are in the form of wire walls.

5. The tritium measuring device with radon compensation function according to claim 2, characterized in that: It also includes an electrical junction box, an air pump, a gas sampling port, a manual valve, a filter, a flow meter, a regulating valve, and a gas exhaust port. The gas sampling port is connected to the air inlet of the measuring unit via the manual valve and the filter, and the air outlet of the measuring unit is connected to the gas exhaust port via the flow meter, the regulating valve, and the air pump. The collector of chamber A in the measuring unit is connected to the current amplification circuit, and the collector of chamber B is connected to the pulse amplification circuit. The output ends of the current amplification circuit and the pulse amplification circuit are connected to the signal processing display unit, and the signal processing display unit is connected to the electrical junction box.

6. The tritium measuring device with radon compensation function according to claim 3, characterized in that: It also includes an electrical junction box, an air pump, a gas sampling port, a solenoid valve, a manual valve, a filter, a flow meter, a regulating valve, and a gas exhaust port. The gas sampling port is connected to the air inlets of chamber A and chamber B in the measuring unit via a manual valve, a filter, and two solenoid valves respectively. The air outlets of chamber A and chamber B are connected to the gas exhaust port via a flow meter, a regulating valve, and an air pump. The collector of chamber A in the measuring unit is connected to a current amplifying circuit, and the collector of chamber B is connected to a pulse amplifying circuit. The output ends of the current amplifying circuit and the pulse amplifying circuit are connected to a signal processing and display unit, and the signal processing and display unit is connected to the electrical junction box.

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