Device and method for detecting radioactive activity concentration of tritium in air

Abstract

The invention relates to the technical field of radiation environment monitoring, and discloses a device and method for detecting the radioactive activity concentration of tritium in air, and the device comprises a sampling unit, a first waste liquid unit, an ion exchange unit, a detection unit, a scintillation liquid unit, a second waste liquid unit and a cleaning unit; the rear end of the sampling unit is respectively connected with the front end of the ion exchange unit and the first waste liquid unit through a first three-way valve, and the rear end of the ion exchange unit is respectively connected with the front end of the detection unit and the first waste liquid unit through a second three-way valve; the front end of the detection unit is connected with the scintillation liquid unit through a first solenoid valve and connected with the cleaning unit through a third solenoid valve, and the rear end of the detection unit is connected with the second waste liquid unit through a second solenoid valve. The device provided by the invention realizes full-automatic acquisition, processing and measurement of tritium in air monitoring, unmanned operation is performed in the monitoring process, possible interference caused by manpower is avoided, and occupational hazards of field high-radiation operation to workers are avoided.

Description

Technical Field

[0001] The present application relates to the technical field of radiation environment monitoring, and in particular to a device and method for detecting the radioactivity concentration of tritium in the air. Background Art

[0002] A large amount of tritium is generated during the operation of nuclear facilities such as reactors, some of which is discharged into the atmosphere through ventilation systems, resulting in an increase in the radioactive concentration of tritium in the surrounding environment. In special circumstances such as emergency response to nuclear accidents, the radioactive concentration of tritium in the air in a local area is more likely to increase significantly. Workers and the public may ingest tritium through various channels, which may cause a certain degree of internal exposure. Therefore, it is necessary to pay great attention to the monitoring of tritium in the air.

[0003] Tritium in the environment is usually distributed in the atmosphere in the form of bound water. At present, for the monitoring of tritium in the air, sampling is generally carried out in the field first, and the samples are collected and transferred to the laboratory for processing, and then measured in a low-background liquid scintillation meter. However, the existing monitoring methods not only increase the risk of sample damage or cross-contamination during transportation and handling, but also cannot achieve continuous sampling and measurement.

[0004] Therefore, there is an urgent need to provide a monitoring device and method for tritium in the air that can operate automatically and continuously. Summary of the invention

[0005] To solve the above problems, the present application provides a device and method for detecting the radioactive activity concentration of tritium in the air, which can improve monitoring efficiency and accuracy while saving labor costs.

[0006] This application adopts the following technical solutions:

[0007] On one hand, the present application provides a device for detecting the radioactivity concentration of tritium in the air, the device comprising: a sampling unit, a first waste liquid unit, an ion exchange unit, a detection unit, a scintillation liquid unit, a second waste liquid unit and a cleaning unit;

[0008] The rear end of the sampling unit is connected to the front end of the ion exchange unit and the first waste liquid unit respectively through the first three-way valve, the rear end of the ion exchange unit is connected to the front end of the detection unit and the first waste liquid unit respectively through the second three-way valve, the front end of the detection unit is also connected to the scintillation liquid unit through the first solenoid valve and the cleaning unit through the third solenoid valve, and the rear end of the detection unit is connected to the second waste liquid unit through the second solenoid valve;

[0009] A sampling unit, for collecting tritiated water vapor in the air as condensed water within the preset sampling time after determining the preset sampling time and determining the average temperature and average humidity of the preset sampling time, and determining the water vapor content in the air during the preset sampling time according to the average temperature and average humidity of the preset sampling time;

[0010] The sampling unit is further used to determine whether the first mass of the condensed water exceeds a first preset value;

[0011] a first waste liquid unit, used to be connected to the sampling unit when the first mass of the condensed water exceeds a first preset value, collect excess condensed water so that the first mass of the condensed water reaches the first preset value, and then disconnect the connection with the sampling unit;

[0012] an ion exchange unit, used to connect with the sampling unit when the first mass of the condensed water does not exceed a first preset value, remove cations and anions in the condensed water to obtain a sample solution, and then disconnect from the sampling unit;

[0013] The ion exchange unit is also used to determine whether the conductivity of the sample liquid exceeds a second preset value;

[0014] The first waste liquid unit is further used to connect with the ion exchange unit when the conductivity of the sample liquid exceeds a second preset value, and disconnect the connection with the ion exchange unit after collecting the sample liquid;

[0015] A detection unit, used to connect to the ion exchange unit when the conductivity of the sample liquid does not exceed a second preset value, and disconnect the connection with the ion exchange unit after collecting a first quantitative amount of the sample liquid;

[0016] The first waste liquid unit is further used to connect with the ion exchange unit after the detection unit collects a first quantitative sample liquid, and disconnect from the ion exchange unit after the remaining sample liquid is collected;

[0017] The detection unit is used to connect with the scintillation liquid unit after collecting a first quantitative sample liquid, and disconnect from the scintillation liquid unit after collecting a second quantitative scintillation liquid;

[0018] The detection unit is further used to mix the sample liquid with the scintillation liquid to form a detection liquid, detect the detection efficiency and the counting rate of the detection liquid, and determine the radioactive activity concentration of tritium in the air according to the water vapor content in the air at a preset sampling time, the first quantitative value, the detection efficiency, and the counting rate of the detection liquid;

[0019] A second waste liquid unit is used to be connected to the detection unit after detection, collect the detected detection liquid, and then disconnect from the detection unit;

[0020] A cleaning unit, which is used to connect with the detection unit after the second waste liquid unit collects the detected detection liquid, so that the cleaning agent flows into the detection unit to clean the detection unit, and then disconnects the connection with the detection unit;

[0021] The second waste liquid unit is also used to be connected with the detection unit after cleaning, and to be disconnected from the detection unit after collecting the cleaning agent.

[0022] Optionally, a sampling unit, including: an air filter, a dehumidifier, a weighing cup, a first balance, an intermediate bottle, a first metering pump, a sample storage bottle and a second balance;

[0023] The air filter is located at the front end of the dehumidifier to remove pollutants from the air;

[0024] A dehumidifier, for collecting the air from which pollutants have been removed for the preset sampling period at a preset power after determining a plurality of preset sampling periods included in the preset sampling duration, to obtain condensed water; wherein the dehumidifier comprises: a water tank, a thermometer and a hygrometer, the water tank being used to store the condensed water, the thermometer being used to determine an average temperature of the preset sampling period, and the hygrometer being used to determine an average humidity of the preset sampling period;

[0025] The front end of the weighing cup is connected to the rear end of the dehumidifier through the fourth solenoid valve; the first balance is set under the weighing cup; the weighing cup is used to connect with the dehumidifier for a connection time after each preset sampling period to collect condensed water, and disconnect from the dehumidifier outside each connection time; the first balance is used to weigh the second mass of condensed water in the weighing cup after each connection time; if the second mass is greater than a third preset value, the preset power of the dehumidifier is reduced; if the second mass is less than the third preset value, the preset power of the dehumidifier is increased;

[0026] The front end of the intermediate bottle is connected to the rear end of the weighing cup through the fifth solenoid valve; the intermediate bottle is used to connect with the weighing cup after the first balance weighs the second mass of the condensed water in the weighing cup after each connection time, so as to collect the condensed water in the weighing cup;

[0027] The front end of the sample storage bottle is connected to the rear end of the intermediate bottle through the first metering pump and the sixth solenoid valve in turn, and the sample storage bottle is respectively connected to the front end of the ion exchange unit and the first waste liquid unit through the first three-way valve; the second balance is arranged under the sample storage bottle; the sample storage bottle is used to connect with the intermediate bottle after all the condensed water of the preset sampling time has flowed into the intermediate bottle, and disconnect the connection with the intermediate bottle after the condensed water is collected by the first metering pump; the second balance is used to weigh the first mass of the condensed water in the sample storage bottle to determine whether the first mass exceeds the first preset value.

[0028] Optionally, an ion exchange unit, including: a vacuum pump, a negative pressure box, an exchange column, a collection cup, a third balance and a conductivity sensor;

[0029] The vacuum pump is connected to the negative pressure box; the vacuum pump is used to keep the negative pressure box in a negative pressure state after it is turned on;

[0030] The front end of the exchange column is connected to the rear end of the sampling unit through a first three-way valve, and the rear end of the exchange column extends deep into the collection cup in the negative pressure box; the exchange column is used to communicate with the sampling unit when the first mass of the condensed water does not exceed the first preset value, so that the condensed water flows in and the cations and anions in the condensed water are removed to obtain the sample liquid, and the sample liquid flows out to the collection cup;

[0031] The rear end of the collection cup is connected to the front end of the detection unit and the first waste liquid unit respectively through the second three-way valve; the third balance is arranged under the collection cup; the collection cup is used to collect the sample liquid; the third balance is used to continuously weigh the third mass of the sample liquid in the collection cup during the process of the sample liquid flowing into the collection cup;

[0032] The conductivity sensor is inserted deep into the collection cup; the conductivity sensor is used to measure the conductivity of the sample liquid when the third mass exceeds the fourth preset value, and determine whether the conductivity of the sample liquid exceeds the second preset value.

[0033] Optionally, the detection unit includes: a second metering pump, a sample bottle with a driving magnet, a magnetic stirring heater and a liquid scintillation measuring instrument; the scintillation liquid unit includes: a third metering pump, a scintillation liquid reserve barrel and a fourth balance;

[0034] The front end of the sample bottle is connected to the rear end of the ion exchange unit through the second metering pump and the second three-way valve in sequence; the magnetic stirring heater is arranged under the sample bottle; the sample bottle and the magnetic stirring heater are arranged in the liquid scintillation measuring instrument; the front end of the sample bottle is also connected to the scintillation liquid reserve barrel through the first electromagnetic valve and the third metering pump in sequence; the fourth balance is arranged under the scintillation liquid reserve barrel;

[0035] The sample bottle is used to connect to the ion exchange unit when the conductivity of the sample liquid does not exceed the second preset value, and disconnect the connection with the ion exchange unit after collecting a first fixed amount of sample liquid through the second metering pump;

[0036] The first waste liquid unit is further used to connect with the ion exchange unit after the sample bottle collects a first quantitative sample liquid, and disconnect with the ion exchange unit after the remaining sample liquid is collected;

[0037] The sample bottle is also used to be connected to the scintillation liquid reserve barrel after collecting a first fixed amount of sample liquid, and to be disconnected from the scintillation liquid reserve barrel after collecting a second fixed amount of scintillation liquid through the third metering pump;

[0038] The magnetic stirring heater is used to start the preset time and drive the driving magnet to heat the sample liquid and the scintillation liquid to mix into the detection liquid;

[0039] Liquid scintillation meter, used to measure the detection efficiency and count rate of the detection liquid after the detection liquid is allowed to stand and dark-processed;

[0040] The fourth balance is used to weigh the fourth mass of the scintillation liquid reserve barrel and to issue a first alarm when the fourth mass is lower than a fifth preset value.

[0041] Optionally, the first waste liquid unit comprises: a first waste liquid bucket and a fifth balance;

[0042] The first waste liquid barrel is connected to the sampling unit through a first three-way valve and is connected to the ion exchange unit through a second three-way valve; a fifth balance is arranged under the first waste liquid barrel;

[0043] A first waste liquid bucket, used for collecting condensed water or sample liquid;

[0044] The fifth balance is used to weigh the fifth mass of the first waste liquid barrel and to issue a second alarm when the fifth mass exceeds a sixth preset value.

[0045] Optionally, the second waste liquid unit includes: a second waste liquid bucket and a sixth balance.

[0046] The second waste liquid barrel is connected to the detection unit through a second solenoid valve; the sixth balance is arranged under the second waste liquid barrel;

[0047] The second waste liquid bucket is used to collect the test liquid, sample liquid or cleaning agent;

[0048] The sixth balance is used to weigh the sixth mass of the second waste liquid bucket and to issue a third alarm when the sixth mass exceeds a seventh preset value.

[0049] Optionally, a cleaning unit comprises: a fourth metering pump, a cleaning agent reserve tank and a seventh balance;

[0050] The cleaning agent reserve barrel is connected to the detection unit through the fourth dosage pump and the third solenoid valve in sequence; the seventh balance is arranged under the cleaning agent reserve barrel;

[0051] a cleaning agent reserve barrel, used to be connected to the detection unit after the detected detection liquid flows into the second waste liquid unit, and disconnected from the detection unit after the cleaning agent is provided to the detection unit through the fourth metering pump;

[0052] The seventh balance is used to weigh the seventh mass of the cleaning agent reserve barrel and to issue a fourth alarm when the seventh mass is lower than an eighth preset value.

[0053] Optionally, the detection unit is further used to connect with the ion exchange unit when the conductivity of the sample liquid does not exceed a second preset value, and after collecting the rinse amount of sample liquid, disconnect the connection with the ion exchange unit;

[0054] The second waste liquid unit is also used to be connected with the detection unit after the detection unit collects the sample liquid of the rinsing amount, and to be disconnected from the detection unit after the detection unit collects the sample liquid of the rinsing amount.

[0055] Optionally, the third balance is further used to weigh the eighth mass of the sample liquid in the collection cup when the conductivity of the sample liquid does not exceed the second preset value, and determine whether the eighth mass exceeds the ninth preset value;

[0056] The first waste liquid unit is further used to connect with the ion exchange unit when the eighth mass exceeds a ninth preset value, collect excess sample liquid so that the eighth mass does not exceed the ninth preset value, and then disconnect from the ion exchange unit;

[0057] The detection unit is further used to connect with the ion exchange unit when the eighth mass does not exceed a ninth preset value, and disconnect the connection with the ion exchange unit after collecting a first quantitative sample liquid.

[0058] On the other hand, the present application provides a method for detecting the radioactivity concentration of tritium in the air, the method comprising:

[0059] Determine a preset sampling time, collect tritiated water vapor in the air as condensed water using a sampling unit within the preset sampling time, and determine an average temperature and an average humidity of the preset sampling time;

[0060] Then the water vapor content ρ in the air at the preset sampling time is:

[0061] ρ = R(T) × RH;

[0062] The unit of ρ is g / m 3 , T represents the average temperature of the preset sampling time, RH represents the average humidity of the preset sampling time, r(T) represents the saturated mass of water vapor in the air corresponding to the average temperature T of the preset sampling time, and the unit of R(T) is g / m 3 ;

[0063] Determining whether a first mass of condensed water exceeds a first preset value;

[0064] If the first mass of the condensed water exceeds the first preset value, the sampling unit is connected to the first waste liquid unit, and the first waste liquid unit is used to collect excess condensed water so that the first mass of the condensed water reaches the first preset value, and then the connection between the sampling unit and the first waste liquid unit is disconnected;

[0065] If the first mass of the condensed water does not exceed the first preset value, the sampling unit is connected to the ion exchange unit; after removing the cations and anions in the condensed water by the ion exchange unit to obtain the sample liquid, the connection between the sampling unit and the ion exchange unit is disconnected;

[0066] Determining whether the conductivity of the sample liquid exceeds a second preset value;

[0067] If the conductivity of the sample liquid exceeds a second preset value, the ion exchange unit is connected to the first waste liquid unit, and after the sample liquid is collected by the first waste liquid unit, the connection between the ion exchange unit and the waste liquid collection unit is disconnected;

[0068] If the conductivity of the sample liquid does not exceed the second preset value, the ion exchange unit is connected to the detection unit, and after the detection unit collects a first quantitative amount of the sample liquid, the connection between the ion exchange unit and the detection unit is disconnected;

[0069] After the detection unit collects a first quantitative sample liquid, the ion exchange unit is connected to the first waste liquid unit, and after the first waste liquid unit collects the remaining sample liquid, the connection between the ion exchange unit and the first waste liquid unit is disconnected;

[0070] After collecting a first quantitative sample liquid, the detection unit is connected to the scintillation liquid unit, and after collecting a second quantitative scintillation liquid by using the detection unit, the connection between the detection unit and the scintillation liquid unit is disconnected;

[0071] Using the detection unit, the sample liquid and the scintillation liquid are mixed into the detection liquid, and the detection efficiency and the counting rate of the detection liquid are detected;

[0072] Then the radioactivity concentration A of tritium in the air is:

[0073]

[0074] The unit of A is Bq / m 3 , n 1 represents the count rate of the test fluid, n 1 The unit is min -1 , n 0 Represents the background count rate of the liquid scintillation meter of the detection unit, n 0 The unit is min -1 , n 0 It is determined by debugging the liquid scintillation meter, e represents the detection efficiency, m represents the first quantity, and the unit of m is g.

[0075] After the detection, the detection unit is connected to the second waste liquid unit, and after the detected detection liquid is collected by the second waste liquid unit, the connection between the detection unit and the second waste liquid unit is disconnected;

[0076] After the second waste liquid unit collects the detected test liquid, the test unit is connected to the cleaning unit, and the cleaning agent is flowed into the test unit by the cleaning unit to clean the test unit, and then the connection between the test unit and the cleaning unit is disconnected;

[0077] After cleaning, the second waste liquid unit is connected to the detection unit, and after the cleaning agent is collected by the second waste liquid unit, the connection between the second waste liquid unit and the detection unit is disconnected.

[0078] The above technical solution adopted in this application can achieve the following beneficial effects:

[0079] The device and method of the present application realize the fully automatic collection, processing and measurement of tritium in the air. It realizes the automatic collection of condensed water, the automatic measurement and judgment of the conductivity of the sample liquid, the automatic feeding and mixing of the sample liquid and the scintillation liquid, the automatic liquid scintillation measurement of the detection liquid, and the automatic cleaning of the detection unit. During the monitoring process, there is no human operation, which avoids the possible interference caused by manual work and makes the measurement results more accurate. It avoids the risk of sample damage or cross contamination during transportation and handling, and at the same time greatly saves labor costs and avoids the occupational hazards of high-radiation operations in the field to workers. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0081] Figure 1 A schematic diagram showing the connection relationship of a device for detecting the radioactivity concentration of tritium in air according to an embodiment of the present application;

[0082] Figure 2 A schematic structural diagram of a device for detecting the radioactivity concentration of tritium in the air according to an embodiment of the present application is shown.

[0083] In the figure: 1, sampling unit, 2, first waste liquid unit, 3, ion exchange unit, 4, detection unit, 5, scintillation liquid unit, 6, second waste liquid unit, 7, cleaning unit, 8, first three-way valve, 9, second three-way valve, 10, first solenoid valve, 11, second solenoid valve, 12, third solenoid valve, 101, air filter, 102, dehumidifier, 103, weighing cup, 104, first balance, 105, intermediate bottle, 106, first metering pump, 107, sample storage bottle, 108, second balance, 109, fourth solenoid valve, 110, fifth solenoid valve, 111, sixth solenoid valve, 1021, water tank, 102 2. Thermometer, 1023. Hygrometer, 201. First waste liquid barrel, 202. Fifth balance, 301. Vacuum pump, 302. Negative pressure box, 303. Exchange column, 304. Collection cup, 305. Third balance, 306. Conductivity sensor, 401. Second metering pump, 402. Sample bottle, 403. Magnetic stirring heater, 404. Liquid scintillation meter, 405. Driving magnet, 501. Third metering pump, 502. Scintillation liquid reserve barrel, 503. Fourth balance, 601. Second waste liquid barrel, 602. Sixth balance, 701. Fourth metering pump, 702. Cleaning agent reserve barrel, 703. Seventh balance. DETAILED DESCRIPTION

[0084] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution of the present application will be clearly and completely described below in combination with the specific embodiments of the present application and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present application.

[0085] The technical solutions provided by various embodiments of the present application are described in detail below in conjunction with the accompanying drawings.

[0086] Figure 1 A schematic diagram showing the connection relationship of a device for detecting the radioactivity concentration of tritium in the air according to an embodiment of the present application is shown. Figure 1 The device for detecting the radioactive activity concentration of tritium in the air of this embodiment comprises: a sampling unit (1), a first waste liquid unit (2), an ion exchange unit (3), a detection unit (4), a scintillation liquid unit (5), a second waste liquid unit (6) and a cleaning unit (7).

[0087] The rear end of the sampling unit (1) is connected to the front end of the ion exchange unit (3) and the first waste liquid unit (2) respectively through a first three-way valve (8); the rear end of the ion exchange unit (3) is connected to the front end of the detection unit (4) and the first waste liquid unit (2) respectively through a second three-way valve (9); the front end of the detection unit (4) is also connected to the scintillation liquid unit (5) through a first electromagnetic valve (10) and to the cleaning unit (7) through a third electromagnetic valve (12); and the rear end of the detection unit (4) is connected to the second waste liquid unit (6) through a second electromagnetic valve (11).

[0088] In this embodiment, the units are connected via pipelines, and the valves between the units are all closed when the device is not in operation.

[0089] The "front end" here is used to indicate the feed end of the unit, and the "rear end" here is used to indicate the outflow end of the unit. For example: the front end of the sampling unit (1) is used to indicate the feed end for air, and the rear end of the sampling unit (1) is used to indicate the outflow end for condensed water; the front end of the ion exchange unit (3) is used to indicate the feed end for condensed water, and the rear end of the ion exchange unit (3) is used to indicate the outflow end for sample liquid; the front end of the detection unit (4) is used to indicate the feed end for sample liquid, the feed end for scintillation liquid, and the feed end for cleaning agent, and the rear end of the detection unit (4) is used to indicate the outflow end for sample liquid, detection liquid or cleaning agent.

[0090] The first waste liquid unit (2) and the second waste liquid unit (6) only involve inflow, and the scintillation liquid unit (5) and the cleaning unit (7) only involve outflow, and therefore are no longer limited by "front end" and "rear end".

[0091] The sampling unit (1) is used to collect tritiated water vapor in the air as condensed water within the preset sampling time after determining the preset sampling time and to determine the average temperature and average humidity of the preset sampling time.

[0092] The preset sampling time may be a sampling time that is manually set in advance. Within the preset sampling time, the sampling unit (1) continuously collects tritiated water vapor in the air as condensed water, and determines the average temperature T and average humidity rH within the preset sampling time.

[0093] Then, through the sampling unit (1), the water vapor content ρ in the air of the preset sampling time can be determined as:

[0094] ρ = R(T) × RH;

[0095] The unit of ρ is g / m 3 , T represents the average temperature of the preset sampling time, RH represents the average humidity of the preset sampling time, R(T) represents the saturated mass of water vapor in the air corresponding to the average temperature T of the preset sampling time, and the unit of R(T) is g / m 3 .

[0096] Due to the processing capacity limitations of the ion exchange unit (3), the detection unit (4) and other units, it is necessary to prevent the sampling unit (1) from collecting excessive condensed water. Therefore, the sampling unit (1) is also used to determine whether the first mass of the condensed water exceeds a first preset value.

[0097] The first preset value may be a value artificially set in advance according to the carrying capacity of each unit and the like.

[0098] If the first mass of the condensed water exceeds the first preset value, it means that the collected condensed water is excessive. At this time, the left side of the first three-way valve (8) is opened to connect the first waste liquid unit (2) with the sampling unit (1).

[0099] The first waste liquid unit (2) is used to collect excess condensed water so that the first mass of the condensed water reaches a first preset value. Afterwards, the left side of the first three-way valve (8) is closed to disconnect the first waste liquid unit (2) from the sampling unit (1).

[0100] If the first mass of the condensed water does not exceed the first preset value, it means that the collected condensed water is not excessive. At this time, the right side of the first three-way valve (8) is opened to connect the ion exchange unit (3) with the sampling unit (1).

[0101] The ion exchange unit (3) is used to remove cations and anions in the condensed water to obtain a sample solution. Afterwards, the right side of the first three-way valve (8) is closed to disconnect the ion exchange unit (3) from the sampling unit (1).

[0102] In order to verify whether the treatment of condensed water by the ion exchange unit (3) meets the requirements, it is necessary to determine whether the conductivity of the sample liquid exceeds a second preset value.

[0103] The second preset value may be a value artificially set in advance according to the requirements of the detection accuracy for the sample liquid, etc.

[0104] If the conductivity of the sample liquid exceeds the second preset value, it means that the treatment of the condensed water by the ion exchange unit (3) does not meet the requirements, and the sample liquid cannot be used for subsequent detection. At this time, the left side of the second three-way valve (9) is opened to connect the first waste liquid unit (2) with the ion exchange unit (3).

[0105] The first waste liquid unit (2) is also used to collect sample liquid that does not meet the requirements. Afterwards, the left side of the second three-way valve (9) is closed to disconnect the first waste liquid unit (2) from the ion exchange unit (3).

[0106] If the conductivity of the sample liquid does not exceed the second preset value, it means that the treatment of the condensed water by the ion exchange unit (3) meets the requirements, and the sample liquid can be used for subsequent detection. At this time, the right side of the second three-way valve (9) is opened to connect the detection unit (4) with the ion exchange unit (3).

[0107] The detection unit (4) is used to collect a first quantitative sample liquid m. Afterwards, the right side of the second three-way valve (9) is closed to disconnect the detection unit (4) from the ion exchange unit (3).

[0108] The first quantitative value m may be a value artificially set in advance according to the detection capability of the detection unit (4).

[0109] After the first quantitative sample solution m flows into the detection unit (4), the sample solution remaining in the ion exchange unit (3) is no longer needed. At this time, the left side of the second three-way valve (9) is opened to connect the first waste liquid unit (2) with the ion exchange unit (3).

[0110] The first waste liquid unit (2) is also used to collect the remaining sample liquid. Afterwards, the left side of the second three-way valve (9) is closed to disconnect the first waste liquid unit (2) from the ion exchange unit (3).

[0111] During the detection, in addition to the sample liquid, a scintillation liquid is also required. Therefore, after the detection unit (4) collects a first quantitative amount m of the sample liquid, the first electromagnetic valve (10) is opened to connect the detection unit (4) with the scintillation liquid unit (5).

[0112] The detection unit (4) is used to collect a second fixed amount of scintillation liquid. Afterwards, the first electromagnetic valve (10) is closed to disconnect the detection unit (4) from the scintillation liquid unit (5).

[0113] The second quantitative value may be a value artificially set in advance based on the first quantitative value m and the detection capability of the detection unit (4).

[0114] The detection unit (4) is also used to mix the sample liquid with the scintillation liquid to form a detection liquid, and to adjust the detection efficiency E and the counting rate n of the detection liquid. 1 Conduct testing.

[0115] Then, through the detection unit (4), the radioactivity concentration A of tritium in the air can be determined as:

[0116]

[0117] The unit of A is Bq / m 3 , n 1 represents the count rate of the test fluid, n 1 The unit is min -1 , n 0 Indicates the background count rate of the liquid scintillation meter, n 0 The unit is min -1 , n 0 It is determined by debugging the liquid scintillation meter, e represents the detection efficiency, m represents the first quantity, and the unit of m is g.

[0118] After the test, the tested test liquid needs to be discharged as waste liquid. Therefore, the second solenoid valve (11) is opened to connect the second waste liquid unit (6) with the test unit (4).

[0119] The second waste liquid unit (6) is used to collect the detected test liquid. Afterwards, the second electromagnetic valve (11) is closed to disconnect the second waste liquid unit (6) from the detection unit (4).

[0120] After the above process is completed, in order to meet the continuous cycle detection requirements of the device, the detection unit (4) needs to be automatically cleaned, and the cleaning process can be cycled several times. Therefore, the third solenoid valve (12) is opened to connect the cleaning unit (7) with the detection unit (4).

[0121] The cleaning unit (7) is used to allow the cleaning agent to flow into the detection unit (4) to clean the detection unit (4). Afterwards, the third electromagnetic valve (12) is closed to disconnect the cleaning unit (7) from the detection unit (4).

[0122] The cleaning agent after cleaning still needs to be discharged. Therefore, the second electromagnetic valve (11) is opened to connect the second waste liquid unit (6) with the detection unit (4).

[0123] The second waste liquid unit (6) is also used to collect the cleaning agent. Afterwards, the second solenoid valve (11) is closed to disconnect the second waste liquid unit (6) from the detection unit (4).

[0124] Figure 2 The schematic diagram of the structure of a device for detecting the radioactivity concentration of tritium in the air according to one embodiment of the present application is shown. Figure 2 , the device proposed in this application is described in detail.

[0125] When monitoring the radioactivity concentration of tritium in the air at a certain sampling point for a preset sampling time, in order to meet the requirements of sampling representativeness and calculation of average temperature and humidity, the preset sampling time can be divided into multiple preset sampling periods.

[0126] The sampling unit (1) comprises: an air filter (101), a dehumidifier (102), a weighing cup (103), a first balance (104), an intermediate bottle (105), a first metering pump (106), a sample storage bottle (107) and a second balance (108).

[0127] The air filter (101) is arranged at the front end of the dehumidifier (102); the front end of the weighing cup (103) is connected to the rear end of the dehumidifier (102) through a fourth electromagnetic valve (109); the first balance (104) is arranged under the weighing cup (103); the front end of the intermediate bottle (105) is connected to the rear end of the weighing cup (103) through a fifth electromagnetic valve (110); the front end of the sample storage bottle (107) is connected to the rear end of the intermediate bottle (105) through a first metering pump (106) and a sixth electromagnetic valve (111) in sequence, and the sample storage bottle (107) is connected to the front end of the ion exchange unit (3) and the first waste liquid unit (2) respectively through a first three-way valve (8); and the second balance (108) is arranged under the sample storage bottle (107).

[0128] The air filter (101) is used to remove pollutants in the air and avoid contamination of condensed water.

[0129] The dehumidifier (102) comprises: a water tank (1021), a thermometer (1022) and a hygrometer (1023). The dehumidifier (102) is used to collect the air after decontamination at a preset power for a preset sampling period to obtain condensed water. The water tank (1021) is used to store the condensed water, the thermometer (1022) is used to determine the average temperature of the preset sampling period, and the hygrometer (1023) is used to determine the average humidity of the preset sampling period.

[0130] The preset power may be a value artificially set in advance based on historical experience or the like.

[0131] After the dehumidifier (102) collects a preset sampling cycle, the fourth electromagnetic valve (109) is opened for a connection time, so that the weighing cup (103) is connected to the dehumidifier (102).

[0132] The weighing cup (103) is used to collect the condensed water of the preset sampling cycle. After the connection time is reached, the fourth solenoid valve (109) is closed to disconnect the weighing cup (103) from the dehumidifier (102). (At this time, the dehumidifier (102) may have started or is ready to start the next preset sampling cycle)

[0133] The first balance (104) is used to weigh the second mass of the condensed water in the preset sampling period and determine whether the second mass is greater than a third preset value.

[0134] The third preset value may be a value manually set in advance according to the carrying capacity of the weighing cup (103) and the like.

[0135] If the second mass is greater than the third preset value, it means that the dehumidifier (102) collects too much condensed water too quickly, and the preset power of the dehumidifier (102) is reduced. If the second mass is less than the third preset value, it means that the dehumidifier (102) collects too little condensed water too slowly, and the preset power of the dehumidifier (102) is increased.

[0136] By adjusting the operating power of the dehumidifier (102) through the second quality feedback of the first balance (104), the collection rate of condensed water can be kept stable.

[0137] After the dehumidifier (102) collects the next preset sampling cycle, the fourth electromagnetic valve (109) opens for a connection time, so that the weighing cup (103) is connected to the dehumidifier (102); the weighing cup (103) collects the condensed water of the next preset sampling cycle; after the connection time is reached, the fourth electromagnetic valve (109) is closed to disconnect the weighing cup (103) from the dehumidifier (102); the first balance (104) weighs the second mass of the condensed water of the next preset sampling cycle, and feeds back the second mass to adjust the operating power of the dehumidifier (102). And so on.

[0138] After the first balance (104) weighs the second mass of condensed water in a preset sampling period each time, the fifth solenoid valve (110) is opened to connect the weighing cup (103) with the intermediate bottle (105).

[0139] The middle bottle (105) is used to collect condensed water in the weighing cup (103).

[0140] That is, the weighing cup (103) only collects condensed water of each preset sampling period, and after being weighed by the first balance (104), it flows into the middle bottle (105). The middle bottle (105) continues to accumulate until the condensed water of the preset sampling time is collected.

[0141] After all the condensed water of the preset sampling time has flowed into the intermediate bottle (105), the sixth solenoid valve (111) is opened to connect the sample storage bottle (107) with the intermediate bottle (105).

[0142] The sample storage bottle (107) is used to collect condensed water through the first metering pump. Afterwards, the sixth solenoid valve (111) is closed to disconnect the sample storage bottle (107) from the intermediate bottle (105).

[0143] The second balance (108) is used to weigh the first mass of condensed water in the sample storage bottle (107) and determine whether the first mass exceeds a first preset value.

[0144] If the first mass exceeds the first preset value, the left side of the first three-way valve (8) is opened to connect the first waste liquid unit (2) with the sample storage bottle (107).

[0145] The first waste liquid unit (2) is also used to collect excess condensed water so that the first mass of the condensed water is a first preset value. Afterwards, the left side of the first three-way valve (8) is closed to disconnect the first waste liquid unit (2) from the sample storage bottle (107). Afterwards, the right side of the first three-way valve (8) is opened to connect the ion exchange unit (3) to the sample storage bottle (107).

[0146] If the first mass does not exceed the first preset value, the right side of the first three-way valve (8) is opened to connect the ion exchange unit (3) with the sample storage bottle (107).

[0147] When the left side of the first three-way valve (8) is opened to discharge excess condensed water, feedback can be given in real time through the second balance (108) as to whether the first mass exceeds the first preset value.

[0148] In addition, since the masses of the condensed water in the intermediate bottle (105) and the sample storage bottle (107) are equal, the second balance (108) can also be set under the intermediate bottle (105), and the first mass of the condensed water in the intermediate bottle (105) is measured to determine whether the first mass exceeds the first preset value. In this case, when the first mass exceeds the first preset value, the first balance (105) calculates the first difference between the first preset value and the first mass. Afterwards, the sixth solenoid valve (111) is opened to connect the sample storage bottle (107) with the intermediate bottle (105). The first metering pump (106) is used to allow the condensed water of the first difference to flow into the sample storage bottle (107). Afterwards, the sixth solenoid valve (111) is closed to disconnect the sample storage bottle (107) from the intermediate bottle (105). Afterwards, the left side of the first three-way valve (8) is opened to connect the first waste liquid unit (2) with the sample storage bottle (107). The first waste liquid unit (2) is used to collect the condensed water of the first difference. Afterwards, the left side of the first three-way valve (8) is closed to disconnect the first waste liquid unit (2) from the sample storage bottle (107). Afterwards, the sixth solenoid valve (111) is opened to connect the sample storage bottle (107) to the intermediate bottle (105). The first metering pump (106) is used to allow the remaining condensed water to flow into the sample storage bottle (107). Afterwards, the sixth solenoid valve (111) is closed to disconnect the sample storage bottle (107) from the intermediate bottle (105). Afterwards, the right side of the first three-way valve (8) is opened to connect the ion exchange unit (3) to the sample storage bottle (107).

[0149] When the preset sampling duration includes n preset sampling periods, the water vapor content ρ in the air during the preset sampling duration is:

[0150]

[0151] Among them, T i Represents the average temperature of the i-th preset sampling period, RH i represents the average humidity of the i-th preset sampling period, R(T i ) represents the average temperature T of the i-th preset sampling period i The corresponding saturated mass of water vapor in the air.

[0152] The ion exchange unit (3) comprises: a vacuum pump (301), a negative pressure box (302), an exchange column (303), a collection cup (304), a third balance (305) and a conductivity sensor (306).

[0153] The vacuum pump (301) is connected to the negative pressure box (302); the front end of the exchange column (303) is connected to the rear end of the sampling unit (1) through a first three-way valve (8), and the rear end of the exchange column (303) extends deep into the collection cup (304) in the negative pressure box (302); the rear end of the collection cup (304) is respectively connected to the front end of the detection unit (4) and the first waste liquid unit (2) through a second three-way valve (9); the third balance (305) is arranged under the collection cup (304); and the conductivity sensor (306) extends deep into the collection cup (304).

[0154] The vacuum pump (301) is used to keep the negative pressure box (302) in a negative pressure state after being turned on. The negative pressure state can speed up the flow rate of condensed water in the exchange column (303).

[0155] When the first mass does not exceed the first preset value, the right side of the first three-way valve (8) is opened to connect the sample storage bottle (107) with the exchange column (303).

[0156] The exchange column (303) is used to allow condensed water to flow in and remove cations and anions in the condensed water to obtain a sample liquid, and then allow the sample liquid to flow out into a collection cup (304).

[0157] The main body of the exchange column (303) is a chromatography column, in which a sand core plate, resin and end plug are placed from bottom to top. A microporous sand core plate made of ceramic is placed at the bottom of the chromatography column, and the fine pores inside the microporous sand core plate can ensure that the resin will not be lost with the condensed water. The chromatography column is filled with resin, and the resin is used to remove impurities in the condensed water. An end plug is placed above the chromatography column to facilitate connection with the sample storage bottle (107) through a pipeline.

[0158] The collection cup (304) is used to collect the sample liquid.

[0159] The third balance (305) is used to continuously weigh the third mass of the sample liquid in the collection cup (304) while the sample liquid flows into the collection cup (304).

[0160] Since the conductivity measurement requires that the third mass of the sample liquid reaches the fourth preset value, when the third mass weighed by the third balance (305) exceeds the fourth preset value, the conductivity sensor (306) is used to measure the conductivity of the sample liquid.

[0161] If the conductivity of the sample liquid exceeds the second preset value, it means that the treatment effect of the exchange column (303) does not meet the requirements. At this time, the left side of the second three-way valve (9) is opened to connect the collection cup (304) with the first waste liquid unit (6).

[0162] The first waste liquid unit (6) is used to collect sample liquid that does not meet the requirements. Afterwards, the left side of the second three-way valve (9) is closed to disconnect the collection cup (304) from the first waste liquid unit (6).

[0163] If the conductivity of the sample solution does not exceed the second preset value, it means that the treatment effect of the exchange column (303) meets the requirements. At this time, the right side of the second three-way valve (9) is opened to connect the collection cup (304) with the detection unit (4).

[0164] The detection unit (4) comprises: a second metering pump (401), a sample bottle with a driving magnet (402), a magnetic stirring heater (403) and a liquid scintillation measuring instrument (404). The scintillation liquid unit (5) comprises: a third metering pump (501), a scintillation liquid reserve barrel (502) and a fourth balance (503).

[0165] The front end of the sample bottle (402) is connected to the rear end of the ion exchange unit (3) through a second metering pump (401) and a second three-way valve (9) in sequence; a magnetic stirring heater (403) is arranged under the sample bottle (402); the sample bottle (402) and the magnetic stirring heater (403) are arranged in a liquid scintillation measuring instrument (404); the front end of the sample bottle (402) is also connected to a scintillation liquid reserve barrel (502) through a first electromagnetic valve (10) and a third metering pump (501) in sequence; and a fourth balance (503) is arranged under the scintillation liquid reserve barrel (502).

[0166] When the conductivity of the sample liquid does not exceed the second preset value, the right side of the second three-way valve (9) is opened to connect the collection cup (304) with the sample bottle (402).

[0167] The sample bottle (402) is used to collect a first fixed amount of sample liquid through the second metering pump (401). Afterwards, the right side of the second three-way valve (9) is closed to disconnect the collection cup (304) from the sample bottle (402).

[0168] After the sample bottle (402) collects a first fixed amount of sample liquid, the left side of the second three-way valve (9) is opened to connect the collection cup (304) with the first waste liquid unit (6).

[0169] The first waste liquid unit (6) is used to collect the remaining sample liquid. Afterwards, the left side of the second three-way valve (9) is closed to disconnect the collection cup (304) from the first waste liquid unit (6).

[0170] After the sample bottle (402) collects a first fixed amount of sample liquid, the first electromagnetic valve (10) is opened to connect the scintillation liquid reserve barrel (502) with the sample bottle (402).

[0171] The sample bottle (402) is also used to collect a second fixed amount of scintillation liquid through the third metering pump (501). Afterwards, the first electromagnetic valve (10) is closed to disconnect the scintillation liquid reserve barrel (502) from the sample bottle (402).

[0172] After the above steps are completed, the magnetic stirring heater (403) is turned on for a preset time, driving the driving magnet (405) to heat and mix the sample liquid and the scintillation liquid into a detection liquid.

[0173] The liquid scintillation measuring instrument (404) is used to measure the detection efficiency and the counting rate of the detection liquid after the detection liquid is allowed to stand and dark-treated.

[0174] The fourth balance (503) is used to weigh the fourth mass of the scintillation liquid reserve barrel (502). If the fourth mass is lower than the fifth preset value, it means that the scintillation liquid reserve is insufficient. At this time, the fourth balance (503) can issue a first alarm.

[0175] The fifth preset value may be a value pre-set manually according to the demand for scintillation liquid, etc. The first alarm may be a liquid shortage alarm.

[0176] In addition, the first waste liquid unit (2) comprises: a first waste liquid barrel (201) and a fifth balance (202).

[0177] The first waste liquid barrel (201) is connected to the sampling unit (1) via a first three-way valve (8) and is connected to the ion exchange unit (3) via a second three-way valve (9); and the fifth balance (202) is arranged under the first waste liquid barrel (201).

[0178] The first waste liquid bucket (201) is used to collect condensed water or sample liquid.

[0179] The fifth balance (202) is used to weigh the fifth weight of the first waste liquid barrel (201) and to issue a first alarm when the fifth weight exceeds a sixth preset value.

[0180] The sixth preset value may be a value artificially set in advance according to the carrying capacity of the first waste liquid barrel (201), etc. The second alarm may be an overflow alarm.

[0181] In addition, the second waste liquid unit (6) includes: a second waste liquid barrel (601) and a sixth balance (602).

[0182] The second waste liquid barrel (601) is connected to the detection unit (4) via a second electromagnetic valve (11); and the sixth balance (602) is arranged under the second waste liquid barrel (601).

[0183] The second waste liquid bucket (202) is used to collect detection liquid, sample liquid or cleaning agent.

[0184] The sixth balance (602) is used to weigh the sixth weight of the second waste liquid bucket (601) and issue a third alarm when the sixth weight exceeds a seventh preset value.

[0185] The seventh preset value may be a value pre-set manually according to the carrying capacity of the second waste liquid barrel (601), etc. The third alarm may be an overflow alarm.

[0186] In addition, the cleaning unit (7) includes: a fourth metering pump (701), a cleaning agent reserve barrel (702) and a seventh balance (703).

[0187] The cleaning agent reserve barrel (702) is connected to the detection unit (4) via the fourth dosage pump (701) and the third solenoid valve (12) in sequence; the seventh balance (703) is arranged under the cleaning agent reserve barrel (702).

[0188] After the tested test liquid flows into the second waste liquid unit (6), the third solenoid valve (12) is opened to connect the cleaning agent reserve barrel (702) with the sample bottle (402);

[0189] The cleaning agent reserve barrel (702) is used to supply cleaning agent to the sample bottle (402) through the fourth metering pump (701). Afterwards, the third solenoid valve (12) is closed to disconnect the cleaning agent reserve barrel (702) from the sample bottle (402).

[0190] The seventh balance (703) is used to weigh the seventh mass of the cleaning agent reserve barrel (702), and to issue a fourth alarm when the seventh mass is lower than an eighth preset value.

[0191] The eighth preset value may be a value pre-set manually according to the demand for cleaning agent, etc. The fourth alarm may be a liquid shortage alarm.

[0192] In order to improve the accuracy of the detection, before the conductivity of the sample liquid does not exceed the second preset value and the sample bottle (402) collects the first quantitative sample liquid, the sample bottle (402) may be rinsed. The rinsing may be repeated several times.

[0193] That is, when the conductivity of the sample liquid does not exceed the second preset value, the right side of the second three-way valve (9) is opened to connect the sample bottle (402) with the collection cup (304).

[0194] The sample bottle (402) is used to collect the rinse amount of sample liquid through the second metering pump (401). Afterwards, the right side of the second three-way valve (9) is closed to disconnect the sample bottle (402) from the collection cup (304).

[0195] After the sample bottle (402) collects the rinse volume of sample liquid, the second solenoid valve (11) is opened to connect the sample bottle (402) with the second waste liquid unit (6).

[0196] The second waste liquid unit (6) is also used to collect the sample liquid of the rinsing volume. Afterwards, the second electromagnetic valve (11) is closed to disconnect the sample bottle (402) from the second waste liquid unit (6).

[0197] In order to ensure that the sample liquid in the collection cup (304) is not excessive, the conductivity of the sample liquid does not exceed the second preset value, the sample bottle (402) collects the first quantitative sample liquid or the sample bottle (402) is rinsed, the eighth mass of the sample liquid can be determined.

[0198] The third balance (305) is also used to weigh the eighth mass of the sample liquid in the collection cup (304) when the conductivity of the sample liquid does not exceed the second preset value, and to determine whether the eighth mass exceeds the ninth preset value.

[0199] If the eighth mass exceeds the ninth preset value, the left side of the second three-way valve (9) is opened to connect the ion exchange unit (3) with the first waste liquid unit (2).

[0200] The first waste liquid unit (2) is also used to collect excess sample liquid so that the eighth mass does not exceed a ninth preset value. Afterwards, the left side of the second three-way valve (9) is closed to disconnect the ion exchange unit (3) from the first waste liquid unit (2). Afterwards, the right side of the second three-way valve (9) is opened to connect the ion exchange unit (3) to the detection unit (4).

[0201] If the eighth mass does not exceed the ninth preset value, the right side of the second three-way valve (9) is opened to connect the ion exchange unit (3) with the detection unit (4).

[0202] The detection unit (4) is also used to collect a first quantitative sample liquid. Afterwards, the right side of the second three-way valve (9) is closed to disconnect the ion exchange unit (3) from the detection unit (4).

[0203] By using the device provided in the present application, a round of detection of the radioactive activity concentration of tritium in the air is achieved.

[0204] In some cases, the preset sampling duration may be 24 hours. In 24 hours, the preset sampling period may be 30 minutes, and the connection duration may be 1 minute. That is, the average temperature and average humidity are recorded every 30 minutes, and the weighing cup (103) is used to collect 1 minute of condensed water every 30 minutes, and the second mass is weighed using the first balance. The second preset value may be 20g, and if the second mass exceeds 20g, the preset power of the dehumidifier (102) is lowered, and if the second mass does not exceed 20g, the preset power of the dehumidifier (102) is increased. After the first balance weighing, the fifth solenoid valve (110) may be opened for 30 seconds to allow condensed water to flow into the middle bottle (105). After the 24-hour preset sampling duration ends, the sixth solenoid valve (111) may be opened for 10 minutes to allow condensed water to flow into the sample storage bottle (107). In the above process, the dehumidifier (102) samples continuously.

[0205] The fourth preset value may be 20 g. If the third mass exceeds 20 g, the conductivity sensor (306) measures the conductivity of the sample liquid. The second preset value may be 5 μS / cm. If the conductivity of the sample liquid exceeds 5 μS / cm, the first waste liquid unit (2) and the ion exchange unit (3) are connected. If the conductivity of the sample liquid does not exceed 5 μS / cm, the detection unit (4) and the ion exchange unit (3) are connected.

[0206] The first quantitative amount can be 8 g, the second quantitative amount can be 12 ml, the mixing time of the sample liquid and the scintillation liquid can be 1 minute, the detection liquid can be left standing and dark-treated for 5 hours, and the measurement time of the liquid scintillation meter can be 12 hours.

[0207] When cleaning the detection unit, 20 ml of cleaning agent can be injected through the fourth metering pump (701) each time, and the magnetic stirring heater (402) is started at 60°C for 30 seconds for cleaning.

[0208] The ninth preset value may be 200 g. When the eighth mass exceeds 200 g, the excess sample liquid needs to be discharged to the first waste liquid unit (2).

[0209] In addition, the preset sampling time can be longer than the total time of the coordinated operation of the ion exchange unit, the first waste liquid unit, the cleaning unit, the scintillation liquid unit, the detection unit and the second waste liquid unit. That is to say, the total time from the opening time point of the right side of the first three-way valve (8) to the time when the condensed water starts to enter the ion exchange unit (3) through the second three-way valve (8) until all the liquid enters the first waste liquid unit or the second waste liquid unit and the cleaning of the detection unit is completed is shorter than the preset sampling time. In this way, it can be ensured that the device can automatically cycle to detect the radioactivity concentration of tritium in the air.

[0210] The device provided by the present invention can realize the fully automatic sampling, processing and measurement functions of monitoring tritium in the air, including fully automatic condensate collection and collection speed control, automatic processing of sample liquid, automatic measurement and judgment of conductivity, automatic feeding and mixing of sample liquid and scintillation liquid, automatic liquid scintillation measurement, and automatic cleaning of the detection unit, and finally realizes the continuous automatic monitoring of tritium in the air. The device provided by the present invention can realize the accurate measurement and recording of information such as condensate collection time, temperature and humidity during the collection process, condensate quality, conductivity of sample liquid, liquid scintillation measurement results, and alarm information, and realize remote monitoring and operation through the network, avoiding possible interference and errors caused by manual measurement. During the whole monitoring process, it can be operated at close range without human intervention, avoiding occupational hazards to workers caused by high-radiation operations in the field.

[0211] Accordingly, the present application also proposes a method for detecting the radioactivity concentration of tritium in the air. The method comprises:

[0212] Determine a preset sampling time, collect tritiated water vapor in the air as condensed water using a sampling unit within the preset sampling time, and determine an average temperature and an average humidity of the preset sampling time;

[0213] Then the water vapor content ρ in the air at the preset sampling time is:

[0214] ρ = R(T) × RH;

[0215] The unit of ρ is g / m 3 , T represents the average temperature of the preset sampling time, RH represents the average humidity of the preset sampling time, R(T) represents the saturated mass of water vapor in the air corresponding to the average temperature T of the preset sampling time, and the unit of R(T) is g / m 3 ;

[0216] Determining whether a first mass of condensed water exceeds a first preset value;

[0217] If the first mass of the condensed water exceeds the first preset value, the sampling unit is connected to the first waste liquid unit, and the first waste liquid unit is used to collect excess condensed water so that the first mass of the condensed water reaches the first preset value, and then the connection between the sampling unit and the first waste liquid unit is disconnected;

[0218] If the first mass of the condensed water does not exceed the first preset value, the sampling unit is connected to the ion exchange unit; after removing the cations and anions in the condensed water by the ion exchange unit to obtain the sample liquid, the connection between the sampling unit and the ion exchange unit is disconnected;

[0219] Determining whether the conductivity of the sample liquid exceeds a second preset value;

[0220] If the conductivity of the sample liquid exceeds a second preset value, the ion exchange unit is connected to the first waste liquid unit, and after the sample liquid is collected by the first waste liquid unit, the connection between the ion exchange unit and the waste liquid collection unit is disconnected;

[0221] If the conductivity of the sample liquid does not exceed the second preset value, the ion exchange unit is connected to the detection unit, and after the detection unit collects a first quantitative amount of the sample liquid, the connection between the ion exchange unit and the detection unit is disconnected;

[0222] After the detection unit collects a first quantitative sample liquid, the ion exchange unit is connected to the first waste liquid unit, and after the first waste liquid unit collects the remaining sample liquid, the connection between the ion exchange unit and the first waste liquid unit is disconnected;

[0223] After collecting a first quantitative sample liquid, the detection unit is connected to the scintillation liquid unit, and after collecting a second quantitative scintillation liquid by using the detection unit, the connection between the detection unit and the scintillation liquid unit is disconnected;

[0224] Using the detection unit, the sample liquid and the scintillation liquid are mixed into the detection liquid, and the detection efficiency and the counting rate of the detection liquid are detected;

[0225] Then the radioactivity concentration A of tritium in the air is:

[0226]

[0227] The unit of A is Bq / m 3 , n 1 represents the count rate of the test fluid, n 1 The unit is min -1 , n 0 Represents the background count rate of the liquid scintillation meter of the detection unit, n 0 The unit is min -1 , n 0 It is determined by debugging the liquid scintillation meter. E represents the detection efficiency, m represents the first quantity, and the unit of m is f.

[0228] After the detection, the detection unit is connected to the second waste liquid unit, and after the detected detection liquid is collected by the second waste liquid unit, the connection between the detection unit and the second waste liquid unit is disconnected;

[0229] After the second waste liquid unit collects the detected test liquid, the test unit is connected to the cleaning unit, and the cleaning agent is flowed into the test unit by the cleaning unit to clean the test unit, and then the connection between the test unit and the cleaning unit is disconnected;

[0230] After cleaning, the second waste liquid unit is connected to the detection unit, and after the cleaning agent is collected by the second waste liquid unit, the connection between the second waste liquid unit and the detection unit is disconnected.

[0231] The present application also provides a method for detecting the radioactivity concentration of tritium in the air. The method includes:

[0232] sampling:

[0233] Determine multiple preset sampling periods included in the preset sampling duration; use an air filter to remove pollutants in the air, use a dehumidifier to collect the air from which pollutants have been removed at a preset power for a preset sampling period to obtain condensed water; wherein, use a water tank to store the condensed water, use a thermometer to determine the average temperature of the preset sampling period, and use a hygrometer to determine the average humidity of the preset sampling period.

[0234] The fourth solenoid valve is opened for a connection time after each preset sampling period to allow the condensed water to flow into the weighing cup, and then the fourth solenoid valve is closed, and the second mass of the condensed water is weighed using the first balance; if the second mass is greater than the third preset value, the preset power of the dehumidifier is reduced; if the second mass is less than the third preset value, the preset power of the dehumidifier is increased.

[0235] After the first day of weighing, open the fifth solenoid valve to allow the condensed water to flow into the middle bottle, then close the fifth solenoid valve; cycle until all the condensed water of the preset sampling time flows into the middle bottle.

[0236] When the preset sampling duration includes n preset sampling periods, the water vapor content ρ in the air during the preset sampling duration is:

[0237]

[0238] Among them, T i Represents the average temperature of the i-th preset sampling period, RH i represents the average humidity of the i-th preset sampling period, R(T i ) represents the average temperature T of the i-th preset sampling period i The corresponding saturated mass of water vapor in the air.

[0239] Open the sixth solenoid valve to allow the condensed water in the middle bottle to flow into the sample storage bottle through the first metering pump, and use the second balance to weigh the first mass of the condensed water in the sample storage bottle; if the first mass exceeds the first preset value, open the left side of the first three-way valve to allow excess condensed water to flow into the first waste liquid barrel and then close the left side of the first three-way valve; if the first mass does not exceed the first preset value, open the right side of the first three-way valve to allow the condensed water to flow into the exchange column.

[0240] deal with:

[0241] When the vacuum pump is turned on to keep the negative pressure box in a negative pressure state, the sample liquid is obtained by removing cations and anions in the condensed water using an exchange column and flows into a collection cup; the third mass of the sample liquid is weighed using a third balance.

[0242] If the third mass exceeds the fourth preset value, the conductivity of the sample liquid is measured using a conductivity sensor; if the conductivity of the sample liquid exceeds the second preset value, the left side of the second three-way valve is opened to allow the sample liquid to flow into the first waste liquid barrel and then the left side of the second three-way valve is closed.

[0243] If the conductivity of the sample liquid does not exceed the second preset value, the eighth mass of the sample liquid is weighed using a third balance.

[0244] If the eighth mass exceeds the ninth preset value, the left side of the second three-way valve is opened to allow the excess sample liquid to flow into the first waste liquid barrel, and then the left side of the second three-way valve is closed.

[0245] If the eighth mass does not exceed the ninth preset value, the right side of the second three-way valve is opened to allow the rinsing amount of sample liquid to flow into the sample bottle through the second metering pump, and then the right side of the second three-way valve is closed. After starting the magnetic stirring heater to rinse the sample bottle, the second solenoid valve is opened to allow the rinsing amount of sample liquid to flow into the second waste liquid bucket, and then the second solenoid valve is closed. Repeat this step several times.

[0246] Measurement:

[0247] Open the right side of the second three-way valve, let the first quantitative sample liquid flow into the sample bottle through the second metering pump, and then close the right side of the second three-way valve; open the first solenoid valve, let the second quantitative scintillation liquid flow into the sample bottle through the third metering pump, and then close the first solenoid valve.

[0248] The magnetic stirring heater was started to mix the sample liquid and the scintillation liquid evenly. After standing and dark treatment, the detection efficiency and the count rate of the detection liquid were measured using a liquid scintillation meter.

[0249] Then, through the detection unit (4), the radioactivity concentration A of tritium in the air can be determined as:

[0250]

[0251] The unit of A is Bq / m 3 , n 1 represents the count rate of the test fluid, n 1 The unit is min -1 , n 0 Indicates the background count rate of the liquid scintillation meter, n 0 The unit is min -1 , n 0 It is determined by debugging the liquid scintillation meter. E represents the detection efficiency, m represents the first quantity, and the unit of m is g.

[0252] The second solenoid valve is opened to allow the detected test liquid to flow into the second waste liquid barrel, and then the second solenoid valve is closed.

[0253] Cleaning:

[0254] Open the third solenoid valve to allow the cleaning agent to flow into the sample bottle through the fourth metering pump, then close the third solenoid valve and start the magnetic stirring heater to clean the sample bottle. After cleaning, open the second solenoid valve to allow the cleaning agent to flow into the second waste liquid bucket, then close the second solenoid valve. Repeat this step several times.

[0255] The above-mentioned method for detecting the radioactivity concentration of tritium in the air corresponds one-to-one to the above-mentioned device for detecting the radioactivity concentration of tritium in the air.

[0256] The above is only the embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the present application.

Claims

1. A device for detecting the radioactivity concentration of tritium in the air, characterized in that: The device comprises: a sampling unit, a first waste liquid unit, an ion exchange unit, a detection unit, a scintillation liquid unit, a second waste liquid unit and a cleaning unit; The rear end of the sampling unit is connected to the front end of the ion exchange unit and the first waste liquid unit respectively through a first three-way valve, the rear end of the ion exchange unit is connected to the front end of the detection unit and the first waste liquid unit respectively through a second three-way valve, the front end of the detection unit is also connected to the scintillation liquid unit through a first solenoid valve and to the cleaning unit through a third solenoid valve, and the rear end of the detection unit is connected to the second waste liquid unit through a second solenoid valve; The sampling unit is used to collect tritiated water vapor in the air as condensed water within the preset sampling time after determining the preset sampling time and determine the average temperature and average humidity of the preset sampling time, and determine the water vapor content in the air for the preset sampling time according to the average temperature and average humidity of the preset sampling time; The sampling unit is further used to determine whether the first mass of the condensed water exceeds a first preset value; The first waste liquid unit is used to connect with the sampling unit when the first mass of the condensed water exceeds the first preset value, collect excess condensed water so that the first mass of the condensed water reaches the first preset value, and then disconnect from the sampling unit; The ion exchange unit is used to connect with the sampling unit when the first mass of the condensed water does not exceed the first preset value, and disconnect from the sampling unit after removing the cations and anions in the condensed water to obtain the sample liquid; The ion exchange unit is further used to determine whether the conductivity of the sample liquid exceeds a second preset value; The first waste liquid unit is further used to connect with the ion exchange unit when the conductivity of the sample liquid exceeds a second preset value, and disconnect the connection with the ion exchange unit after collecting the sample liquid; The detection unit is used to connect with the ion exchange unit when the conductivity of the sample liquid does not exceed a second preset value, and disconnect the connection with the ion exchange unit after collecting a first quantitative amount of the sample liquid; The first waste liquid unit is further used to connect with the ion exchange unit after the detection unit collects a first quantitative sample liquid, and disconnect from the ion exchange unit after the remaining sample liquid is collected; The detection unit is used to communicate with the scintillation liquid unit after collecting a first quantitative sample liquid, and to disconnect from the scintillation liquid unit after collecting a second quantitative scintillation liquid; The detection unit is further used to mix the sample liquid with the scintillation liquid to form a detection liquid, detect the detection efficiency and the counting rate of the detection liquid, and determine the radioactivity concentration of tritium in the air according to the water vapor content in the air at a preset sampling time, the first quantitative value, the detection efficiency, and the counting rate of the detection liquid; The second waste liquid unit is used to be connected to the detection unit after detection, collect the detected detection liquid, and then disconnect from the detection unit; The cleaning unit is used to connect with the detection unit after the second waste liquid unit collects the detected detection liquid, so that the cleaning agent flows into the detection unit to clean the detection unit, and then disconnect the connection with the detection unit; The second waste liquid unit is also used to be connected to the detection unit after cleaning, and to be disconnected from the detection unit after collecting the cleaning agent.

2. The device for detecting the radioactivity concentration of tritium in the air according to claim 1, characterized in that: The sampling unit comprises: an air filter, a dehumidifier, a weighing cup, a first balance, an intermediate bottle, a first metering pump, a sample storage bottle and a second balance; The air filter is arranged at the front end of the dehumidifier and is used to remove pollutants in the air; The dehumidifier is used to collect the air from which pollutants have been removed for the preset sampling period at a preset power after determining a plurality of preset sampling periods included in the preset sampling duration, to obtain condensed water; wherein the dehumidifier comprises: a water tank, a thermometer and a hygrometer, the water tank being used to store condensed water, the thermometer being used to determine the average temperature of the preset sampling period, and the hygrometer being used to determine the average humidity of the preset sampling period; The front end of the weighing cup is connected to the rear end of the dehumidifier through a fourth solenoid valve; the first balance is arranged under the weighing cup; the weighing cup is used to connect with the dehumidifier for a connection time after each preset sampling period to collect condensed water, and disconnect from the dehumidifier outside each connection time; the first balance is used to weigh the second mass of the condensed water in the weighing cup after each connection time; if the second mass is greater than a third preset value, the preset power of the dehumidifier is reduced; if the second mass is less than the third preset value, the preset power of the dehumidifier is increased; The front end of the intermediate bottle is connected to the rear end of the weighing cup through a fifth solenoid valve; the intermediate bottle is used to be connected to the weighing cup after the first balance weighs the second mass of the condensed water in the weighing cup after each connection time, so as to collect the condensed water in the weighing cup; The front end of the sample storage bottle is connected to the rear end of the intermediate bottle through the first metering pump and the sixth solenoid valve in sequence, and the sample storage bottle is respectively connected to the front end of the ion exchange unit and the first waste liquid unit through the first three-way valve; the second balance is arranged under the sample storage bottle; the sample storage bottle is used to connect with the intermediate bottle after all the condensed water of a preset sampling time has flowed into the intermediate bottle, and disconnect the connection with the intermediate bottle after the condensed water is collected by the first metering pump; the second balance is used to weigh the first mass of the condensed water in the sample storage bottle to determine whether the first mass exceeds a first preset value.

3. The device for detecting the radioactivity concentration of tritium in the air according to claim 1, characterized in that: The ion exchange unit comprises: a vacuum pump, a negative pressure box, an exchange column, a collection cup, a third balance and a conductivity sensor; The vacuum pump is connected to the negative pressure box; the vacuum pump is used to keep the negative pressure box in a negative pressure state after being turned on; The front end of the exchange column is connected to the rear end of the sampling unit through the first three-way valve, and the rear end of the exchange column penetrates into the collection cup in the negative pressure box; the exchange column is used to communicate with the sampling unit when the first mass of the condensed water does not exceed the first preset value, so that the condensed water flows in and the cations and anions in the condensed water are removed to obtain the sample liquid, and the sample liquid flows out to the collection cup; The rear end of the collection cup is connected to the front end of the detection unit and the first waste liquid unit respectively through the second three-way valve; the third balance is arranged under the collection cup; the collection cup is used to collect the sample liquid; the third balance is used to continuously weigh the third mass of the sample liquid in the collection cup during the process of the sample liquid flowing into the collection cup; The conductivity sensor is inserted into the collection cup; the conductivity sensor is used to measure the conductivity of the sample liquid when the third mass exceeds the fourth preset value, and determine whether the conductivity of the sample liquid exceeds the second preset value.

4. The device for detecting the radioactivity concentration of tritium in the air according to claim 1, characterized in that: The detection unit comprises: a second metering pump, a sample bottle with a driving magnet, a magnetic stirring heater and a liquid scintillation measuring instrument; the scintillation liquid unit comprises: a third metering pump, a scintillation liquid reserve barrel and a fourth balance; The front end of the sample bottle is connected to the rear end of the ion exchange unit through the second metering pump and the second three-way valve in sequence; the magnetic stirring heater is arranged under the sample bottle; the sample bottle and the magnetic stirring heater are arranged in the liquid scintillation measuring instrument; the front end of the sample bottle is also connected to the scintillation liquid reserve barrel through the first electromagnetic valve and the third metering pump in sequence; the fourth balance is arranged under the scintillation liquid reserve barrel; The sample bottle is used to connect with the ion exchange unit when the conductivity of the sample liquid does not exceed the second preset value, and disconnect from the ion exchange unit after collecting the first quantitative sample liquid through the second metering pump; The first waste liquid unit is further used to connect with the ion exchange unit after the sample bottle collects a first quantitative sample liquid, and disconnect from the ion exchange unit after the remaining sample liquid is collected; The sample bottle is further used to be connected to the scintillation liquid reserve barrel after collecting a first quantitative amount of sample liquid, and to be disconnected from the scintillation liquid reserve barrel after collecting a second quantitative amount of scintillation liquid through the third metering pump; The magnetic stirring heater is used to start for a preset time, driving the driving magnet to heat and mix the sample liquid and the scintillation liquid into a detection liquid; The liquid scintillation measuring instrument is used to measure the detection efficiency and the counting rate of the detection liquid after the detection liquid is allowed to stand and dark-treated; The fourth balance is used to weigh the fourth mass of the scintillation liquid reserve barrel, and to issue a first alarm when the fourth mass is lower than a fifth preset value.

5. The device for detecting the radioactivity concentration of tritium in the air according to claim 1, characterized in that: The first waste liquid unit comprises: a first waste liquid bucket and a fifth balance; The first waste liquid barrel is connected to the sampling unit through the first three-way valve and is connected to the ion exchange unit through the second three-way valve; the fifth balance is arranged under the first waste liquid barrel; The first waste liquid bucket is used to collect condensed water or sample liquid; The fifth balance is used to weigh the fifth mass of the first waste liquid barrel and to issue a second alarm when the fifth mass exceeds a sixth preset value.

6. The device for detecting the radioactivity concentration of tritium in the air according to claim 1, characterized in that: The second waste liquid unit includes: a second waste liquid bucket and a sixth balance. The second waste liquid barrel is connected to the detection unit through the second solenoid valve; the sixth balance is arranged under the second waste liquid barrel; The second waste liquid bucket is used to collect detection liquid, sample liquid or cleaning agent; The sixth balance is used to weigh the sixth mass of the second waste liquid barrel and to issue a third alarm when the sixth mass exceeds a seventh preset value.

7. The device for detecting the radioactivity concentration of tritium in the air according to claim 1, characterized in that: The cleaning unit comprises: a fourth metering pump, a cleaning agent reserve barrel and a seventh balance; The cleaning agent reserve barrel is connected to the detection unit through the fourth dosage pump and the third solenoid valve in sequence; the seventh balance is arranged under the cleaning agent reserve barrel; The cleaning agent reserve barrel is used to be connected with the detection unit after the detected detection liquid flows into the second waste liquid unit, and disconnected from the detection unit after the cleaning agent is provided to the detection unit by the fourth metering pump; The seventh balance is used to weigh the seventh mass of the cleaning agent reserve barrel, and to issue a fourth alarm when the seventh mass is lower than an eighth preset value.

8. The device for detecting the radioactivity concentration of tritium in the air according to claim 1, characterized in that: The detection unit is further used to connect with the ion exchange unit when the conductivity of the sample liquid does not exceed a second preset value, and disconnect the connection with the ion exchange unit after collecting the rinse amount of sample liquid; The second waste liquid unit is further used to be connected with the detection unit after the detection unit collects the sample liquid of the rinsing amount, and to be disconnected from the detection unit after the sample liquid of the rinsing amount is collected.

9. The device for detecting the radioactivity concentration of tritium in the air according to claim 3, characterized in that: The third balance is further used to weigh the eighth mass of the sample liquid in the collection cup when the conductivity of the sample liquid does not exceed the second preset value, and to determine whether the eighth mass exceeds the ninth preset value; The first waste liquid unit is further used to connect with the ion exchange unit when the eighth mass exceeds a ninth preset value, collect excess sample liquid so that the eighth mass does not exceed the ninth preset value, and then disconnect from the ion exchange unit; The detection unit is further used to connect with the ion exchange unit when the eighth mass does not exceed a ninth preset value, and disconnect from the ion exchange unit after collecting a first quantitative sample liquid.

10. A method for detecting the radioactivity concentration of tritium in the air, characterized in that: The method comprises: Determine a preset sampling time, collect tritiated water vapor in the air as condensed water using a sampling unit within the preset sampling time, and determine an average temperature and an average humidity of the preset sampling time; Then the water vapor content ρ in the air at the preset sampling time is: ρ = R(T) × RH; The unit of ρ is g / m 3 , T represents the average temperature of the preset sampling time, RH represents the average humidity of the preset sampling time, R(T) represents the saturated mass of water vapor in the air corresponding to the average temperature T of the preset sampling time, and the unit of R(T) is g / m 3 ; Determining whether a first mass of condensed water exceeds a first preset value; If the first mass of the condensed water exceeds a first preset value, the sampling unit is connected to the first waste liquid unit, and the first waste liquid unit is used to collect excess condensed water so that the first mass of the condensed water reaches the first preset value, and then the connection between the sampling unit and the first waste liquid unit is disconnected; If the first mass of the condensed water does not exceed the first preset value, the sampling unit is connected to the ion exchange unit; after removing the cations and anions in the condensed water by the ion exchange unit to obtain the sample liquid, the connection between the sampling unit and the ion exchange unit is disconnected; Determining whether the conductivity of the sample liquid exceeds a second preset value; If the conductivity of the sample liquid exceeds a second preset value, the ion exchange unit is connected to the first waste liquid unit, and after the sample liquid is collected by the first waste liquid unit, the connection between the ion exchange unit and the waste liquid collection unit is disconnected; If the conductivity of the sample liquid does not exceed a second preset value, the ion exchange unit is connected to the detection unit, and after the detection unit collects a first quantitative amount of the sample liquid, the connection between the ion exchange unit and the detection unit is disconnected; After the detection unit collects a first quantitative sample liquid, the ion exchange unit is connected to the first waste liquid unit, and after the first waste liquid unit collects the remaining sample liquid, the connection between the ion exchange unit and the first waste liquid unit is disconnected; After collecting a first quantitative sample liquid, the detection unit is connected to the scintillation liquid unit, and after collecting a second quantitative scintillation liquid by using the detection unit, the connection between the detection unit and the scintillation liquid unit is disconnected; Using the detection unit, the sample liquid and the scintillation liquid are mixed into a detection liquid, and the detection efficiency and the counting rate of the detection liquid are detected; Then the radioactivity concentration A of tritium in the air is: The unit of A is Bq / m 3 , n1 represents the counting rate of the detection liquid, and the unit of n1 is min -1 , n0 represents the background count rate of the liquid scintillation meter of the detection unit, and the unit of n0 is min -1 , n0 is determined by debugging the liquid scintillation meter, E represents the detection efficiency, m represents the first quantity, and the unit of m is g. After the detection, the detection unit is connected to the second waste liquid unit, and after the detected detection liquid is collected by the second waste liquid unit, the connection between the detection unit and the second waste liquid unit is disconnected; After the second waste liquid unit collects the detected detection liquid, the detection unit is connected with the cleaning unit, and the cleaning agent is flowed into the detection unit by the cleaning unit to clean the detection unit, and then the connection between the detection unit and the cleaning unit is disconnected; After cleaning, the second waste liquid unit is connected to the detection unit, and after the cleaning agent is collected by the second waste liquid unit, the connection between the second waste liquid unit and the detection unit is disconnected.

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