An on-line monitoring device and method for tritium concentration in liquid effluent of nuclear facilities

Abstract

The application discloses a device and method for online monitoring of tritium concentration in liquid effluent of a nuclear facility. The device comprises a bypass monitoring pipeline, a tritiated water vapor generator connected to the bypass monitoring pipeline, and an output end of a gaseous tritium concentration measuring instrument communicated with a nuclear facility effluent discharge pipeline through an exhaust pipe. The method comprises the following steps: 1) collecting liquid effluent of the nuclear facility; 2) starting a gas pump to start bubbling; 3) measuring the temperature of the liquid in the bubbler; 4) obtaining the liquid tritiated water concentration in a first temperature value range; 5) obtaining the liquid tritiated water concentration in a second temperature value range; 6) obtaining the liquid tritiated water concentration in a next temperature value range; 7) obtaining the final liquid tritiated water concentration under N different temperature data; and 8) calculating the tritium concentration value in the liquid effluent of the nuclear facility. The application converts the monitoring of liquid tritium in the liquid effluent into the monitoring of gaseous tritium, and then obtains the liquid tritium concentration through back calculation, so that the real-time online monitoring target is achieved, and the monitoring is safe and accurate.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of ionizing radiation metrology and environmental radioactivity monitoring, and particularly relates to a device and method for online monitoring of tritium concentration in liquid effluent of a nuclear facility. BACKGROUND

[0002] In a nuclear facility, tritium is mainly produced by the interaction of light water or heavy water with neutrons, and is one of the important by-products in the operation process of a nuclear power plant. Since tritium can exist in gaseous or liquid form and easily enter the environment through various channels, monitoring tritium in the liquid effluent of a nuclear facility is of great significance to ensure the safe operation of a nuclear power plant and environmental protection.

[0003] In the liquid effluent of a nuclear facility, monitoring of tritium is an important part of environmental radiation protection and safety assessment. According to GB6249-2011 "Regulations for Environmental Radiation Protection of Nuclear Power Plants" and HJT 61-2021 "Technical Specifications for Radiation Environmental Monitoring", monitoring of tritium concentration in liquid effluent must be carried out regularly to ensure the safety of nuclear facility operation and environmental protection. Currently, the monitoring of tritium concentration in liquid effluent mainly uses offline sampling method. Although this method can accurately detect the concentration of tritium, it has the disadvantages of manual operation, time-consuming and labor-intensive, inability to achieve continuous monitoring, large manual task, limited frequency of offline sampling, low monitoring efficiency, slow emergency response, inability to monitor the reactor operation state in real time, and difficulty in timely detection of abnormal conditions. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a device for online monitoring of tritium concentration in liquid effluent of a nuclear facility, which is novel and reasonable in design, converts the monitoring of liquid tritium in liquid effluent into the monitoring of gaseous tritium, and then calculates the liquid tritium concentration by back calculation, thereby achieving the goal of real-time online monitoring of tritium concentration in liquid effluent of a nuclear facility, improving the monitoring efficiency and accuracy, eliminating the need for frequent manual sampling, ensuring the safety of employees and the public, avoiding the risk of exposure during sampling by operators, helping to real-time monitor the radiation level in liquid water around the nuclear facility, ensuring the safety of the public, and facilitating popularization and use.

[0005] To solve the above technical problems, the technical solution adopted by the present application is: a device for online monitoring of tritium concentration in liquid effluent of a nuclear facility, characterized in that: a bypass monitoring pipeline is arranged beside a nuclear facility effluent discharge pipeline, both ends of the bypass monitoring pipeline are in communication with the nuclear facility effluent discharge pipeline, a tritiated water vapor generator is connected to the bypass monitoring pipeline, an output end of the tritiated water vapor generator is connected to a gaseous tritium concentration measuring instrument through a gas conveying pipe, an output end of the gaseous tritium concentration measuring instrument is in communication with the nuclear facility effluent discharge pipeline through an exhaust pipe, and a signal output end of the gaseous tritium concentration measuring instrument is in communication with a monitoring terminal.

[0006] The online monitoring device for tritium concentration in liquid effluent of a nuclear facility has the feature that first valves are installed at both ends of the bypass monitoring pipeline.

[0007] The online monitoring device for tritium concentration in liquid effluent of a nuclear facility has the feature that the tritiated water vapor generator comprises a bubbler in communication with the bypass monitoring pipeline, the bubbler is wrapped with and in physical contact with cold hydrazine, a thermometer for measuring the temperature of the liquid effluent of the nuclear facility is installed on the bubbler, a temperature regulator for adjusting the temperature in the cold hydrazine is installed on the cold hydrazine, an air inlet pipe is installed at the input end of the bubbler, a drying bottle, a third valve, an air pump and a gas flow meter are sequentially installed on the air inlet pipe, an air taking pipe is connected to the input end of the drying bottle, and a second valve is installed on the air taking pipe.

[0008] The online monitoring device for tritium concentration in liquid effluent of a nuclear facility has the feature that the air inlet end of the air feeding pipe is in communication with the output end of the bubbler, and a fourth valve is installed on the air feeding pipe.

[0009] The online monitoring device for tritium concentration in liquid effluent of a nuclear facility has the feature that a fifth valve is installed on the air outlet pipe.

[0010] The online monitoring device for tritium concentration in liquid effluent of a nuclear facility has the feature that the installation height of the gaseous tritium concentration measuring instrument is higher than the effluent discharge pipeline of the nuclear facility, so as to prevent the liquid effluent of the nuclear facility from entering the gaseous tritium concentration measuring instrument.

[0011] Meanwhile, the application also discloses a method for online monitoring of tritium concentration in liquid effluent of a nuclear facility, which has the following steps:

[0012] Step one: collecting the liquid effluent of the nuclear facility, adjusting the opening degree of the first valve to control the flow speed of the liquid effluent of the nuclear facility, opening the cold trap and setting the temperature of the cold trap to a first temperature value T1 through the temperature regulator, and then making the liquid effluent of the nuclear facility enter the inside of the bubbler along the bypass monitoring pipeline;

[0013] Step two: starting the air pump to begin bubbling, opening the second valve, the third valve, the fourth valve and the fifth valve installed on the air outlet pipe, and starting the air pump to begin bubbling, and adjusting the opening degrees of the second valve, the third valve, the fourth valve and the fifth valve to leave a set volume of gas above the liquid surface in the bubbler, and the air outlet end of the air inlet pipe is extended to below the liquid surface in the bubbler;

[0014] Step three: measuring the temperature of the liquid in the bubbler, and measuring the temperature of the liquid in the bubbler in real time through the thermometer;

[0015] Step 4: Obtain the liquid tritium concentration within the first temperature range: Observe the real-time thermometer reading T1'. When |T1-T1'| < 0.1, begin recording the temperature reading of the gaseous tritium concentration measuring instrument within the first temperature range T1. According to the reading of the gaseous tritium concentration measuring instrument Back-calculation of liquid tritium water concentration within the first temperature range T1

[0016] Record the readings of the gaseous tritium concentration measuring instrument multiple times within the range of the first temperature value T1. And respectively, the concentration of liquid tritium water within multiple first temperature values ​​T1 ranges was calculated. Using multiple reverse deductions The average value is taken as the final liquid tritium water concentration within the first temperature range T1.

[0017] Step 5: Obtain the liquid tritium concentration within the second temperature range: Set the cold trap temperature to the second temperature value T2 using the temperature regulator, where the second temperature value T2 is higher than the first temperature value T1. Observe the real-time reading T2' of the thermometer. When |T2-T2'| < 0.1, begin recording the temperature reading of the gaseous tritium concentration measuring instrument within the second temperature range T2. According to the readings of the gaseous tritium concentration measuring instrument Back-calculation of liquid tritium water concentration within the range of the second temperature value T2

[0018] The readings of the gaseous tritium concentration measuring instrument were recorded multiple times within the range of the second temperature value T2. And respectively, the concentration of liquid tritium water within multiple second temperature values ​​T2 ranges was calculated. Using multiple reverse deductions The average value is taken as the final liquid tritium concentration within the second temperature range T2.

[0019] Step 6: Obtain the liquid tritium water concentration within the next temperature range: Set the cold trap temperature to the nth temperature value T using a temperature regulator. n Wherein, the nth temperature value T n Higher than the (n-1)th temperature value T n-1 n is a positive integer greater than 2, and the real-time reading T of the thermometer is observed. n ',When|T n -T n After | < 0.1, start recording the nth temperature value T. n The readings of the gaseous tritium concentration measuring instrument within the range According to the readings of the gaseous tritium concentration measuring instrument Back-calculation of the nth temperature value T n Liquid tritium concentration within the range

[0020] The nth temperature value T n The degree of the gaseous tritium concentration measuring instrument in the range And respectively back to the nth temperature value T n The liquid tritium water concentration in the range The average value of the plurality of back-propagated The average value of the plurality of back-propagated n The final liquid tritium water concentration in the range

[0021] Step seven, repeatedly step six until the sampling is completed, and the final liquid tritium water concentration under N different temperature data is obtained, wherein N is the total number of temperature times set by the temperature regulator;

[0022] Step eight, according to the formula The tritium concentration value A in the liquid effluent of the nuclear facility is calculated G .

[0023] The online monitoring method for the tritium concentration in the liquid effluent of the nuclear facility has the characteristics that the nth temperature value T n The temperature difference between the nth-1 temperature value T n-1 Is 1-3 DEG C.

[0024] Compared with the prior art, the present application has the following advantages:

[0025] 1. The present application is based on the principle of a communicating vessel, and the liquid effluent is extracted from the original nuclear facility liquid effluent discharge in real time, and then converted into a gas, and the tritium concentration in the converted gas is read in real time based on a gaseous tritium concentration measuring instrument, and then the tritium concentration in the liquid effluent of the nuclear facility is quickly calculated, the monitoring of tritium in the liquid effluent is converted into the monitoring of gaseous tritium, and the real-time monitoring goal is achieved. By continuously sampling from the liquid effluent of the nuclear facility and converting it into a gas in real time, the volume activity of tritium in the gas is monitored in real time using a tritium concentration online measuring instrument, and the concentration of tritiated water vapor and liquid tritiated water at different temperatures is used to quickly obtain the tritium concentration in the liquid effluent.

[0026] 2. The present application improves the monitoring efficiency and accuracy, and the online continuous monitoring method can detect the tritium concentration in the liquid effluent in real time and continuously, without frequent manual sampling. Not only does it improve the efficiency of monitoring, but it also reduces the errors caused by human operation, thereby improving the accuracy of the data.

[0027] 3、The present application can timely find abnormal conditions, through the online monitoring system, the tritium concentration change in the nuclear facility operation process can be continuously tracked, once the abnormal condition is found, such as the sudden increase of tritium concentration, the early warning information can be sent in the shortest time, remind to take corresponding emergency measures immediately, avoid the expansion of the situation, enhance the emergency response ability, in the case of nuclear accident, the leakage of radioactive substances needs long time continuous monitoring, the online monitoring system can provide long time data record and analysis, help the decision maker better understand the accident development process, and formulate effective countermeasures; Ensure the safety of employees and the public, the application of online continuous monitoring method avoids the exposure risk existing in the sampling process of the operator, helps to master the radiation level of liquid water around the nuclear facility in real time, and ensures the safety of the public.

[0028] To sum up, the present application is novel and reasonable, and the monitoring of liquid tritium in liquid effluent is converted into gaseous tritium monitoring, and then the liquid tritium concentration is obtained through back calculation, so that the real-time online monitoring of tritium concentration in nuclear facility liquid effluent is realized, the monitoring efficiency and accuracy are improved, frequent manual sampling is not required, the safety of employees and the public is ensured, the exposure risk existing in the sampling process of the operator is avoided, the radiation level of liquid water around the nuclear facility is mastered in real time, the safety of the public is ensured, and the present application is convenient to popularize and use.

[0029] The technical solutions of the present application are further described in detail below with reference to the drawings and examples. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The structure connection diagram of the device used in the present application.

[0031] Figure 2 The flowchart of the method of the present application.

[0032] BRIEF DESCRIPTION OF DRAWINGS:

[0033] 1 - nuclear facility effluent discharge pipeline; 2 - first valve;

[0034] 3 - bypass monitoring pipeline; 4 - cold trap; 5 - bubbler;

[0035] 6 - temperature regulator; 7 - air inlet pipe; 8 - air outlet pipe;

[0036] 9 - drying bottle; 10 - gas conveying pipe; 11 - gas pump;

[0037] 12 - gas flow meter; 13-1 - second valve; 13-2 - third valve;

[0038] 13-3 - fourth valve; 13-4 - fifth valve; 14 - thermometer;

[0039] 15—Gastric tritium concentration measuring instrument; 16—Exhaust pipe. Detailed Implementation

[0040] like Figure 1 As shown, the present invention discloses an online monitoring device for tritium concentration in liquid effluents of a nuclear facility, comprising a bypass monitoring pipe 3 disposed beside a nuclear facility effluent discharge pipe 1. Both ends of the bypass monitoring pipe 3 are connected to the nuclear facility effluent discharge pipe 1. A tritized water vapor generator is connected to the bypass monitoring pipe 3. The output end of the tritized water vapor generator is connected to a gaseous tritium concentration measuring instrument 15 through a gas supply pipe 10. The output end of the gaseous tritium concentration measuring instrument 15 is connected to the nuclear facility effluent discharge pipe 1 through an exhaust pipe 16. The signal output end of the gaseous tritium concentration measuring instrument 15 communicates with a monitoring terminal.

[0041] In this embodiment, a first valve 2 is installed at both ends of the bypass monitoring pipeline 3.

[0042] In this embodiment, the tritium vapor generator includes a bubbler 5 connected to the bypass monitoring pipeline 3. The bubbler 5 is wrapped with a cold hydrazine 4 and is in physical contact with the cold hydrazine 4. A thermometer 14 for measuring the temperature of liquid effluent from the nuclear facility is installed on the bubbler 5. A temperature regulator 6 for adjusting the temperature inside the cold hydrazine 4 is installed on the cold hydrazine 4. An inlet pipe 7 is installed at the input end of the bubbler 5. A drying bottle 9, a third valve 13-2, a gas pump 11 and a gas flow meter 12 are installed sequentially on the inlet pipe 7. A gas take-up pipe 8 is connected to the input end of the drying bottle 9. A second valve 13-1 is installed on the gas take-up pipe 8.

[0043] In this embodiment, the air inlet of the air supply pipe 10 is connected to the output of the bubbler 5, and a fourth valve 13-3 is installed on the air supply pipe 10.

[0044] In this embodiment, a fifth valve 13-4 is installed on the exhaust pipe 16.

[0045] In this embodiment, the gaseous tritium concentration measuring instrument 15 is installed at a height higher than the nuclear facility effluent discharge pipe 1 to prevent liquid effluent from the nuclear facility from entering the gaseous tritium concentration measuring instrument 15.

[0046] It should be noted that the first valve 2 refers to a valve that controls liquid flow by physically blocking or adjusting the cross-sectional area of ​​the flow channel, including ball valves, gate valves, globe valves, butterfly valves, and needle valves; the bypass monitoring pipeline 3 is a pipeline capable of transporting liquid, preferably made of metal materials such as stainless steel or copper, but can also be made of inorganic glass; the cold trap 4 includes semiconductor thermostatic cold traps and compressor thermostatic cold traps; the drying bottle 9 is made of stainless steel or glass and contains a moisture-absorbing dryer, such as silica or activated carbon; the air inlet pipe 7 is for gas extraction. Pipe 8, gas supply pipe 10, and exhaust pipe 16 are preferably made of stainless steel or copper. The second valve 13-1, the third valve 13-2, the fourth valve 13-3, and the fifth valve 13-4 include ball valves, solenoid valves, butterfly valves, and plug valves. The gaseous tritium concentration measuring instrument 15 is usually based on the principle of a proportional counter or ionization chamber, which can realize the effective direct measurement of gaseous tritium activity and can display the measurement results online in real time. The horizontal position should be much higher than the nuclear facility effluent discharge pipe 1 to prevent liquid effluent from entering the ionization chamber cavity.

[0047] In practical applications, based on the principle of communicating vessels, liquid effluents from existing nuclear facilities are extracted in real time and rapidly converted into gaseous state. Then, the tritium concentration in the converted gas is read online in real time by a gaseous tritium concentration measuring instrument, thereby quickly calculating the tritium concentration in the liquid effluents of the nuclear facilities. This transforms the monitoring of tritium in liquid effluents into the monitoring of gaseous tritium, thus achieving the goal of real-time monitoring. By continuously sampling from the liquid effluents of nuclear facilities and converting them into gas in real time, the volume activity of tritium in the gas is monitored in real time using an online tritium concentration measuring instrument. By utilizing the correlation between the concentrations of tritized water vapor and liquid tritized water at different temperatures, the tritium concentration in the liquid effluents can be quickly obtained.

[0048] like Figure 2 A method for online monitoring of tritium concentration in liquid effluent from a nuclear facility, as shown, includes the following steps:

[0049] Step 1: Collecting liquid effluent from nuclear facilities: Adjust the opening of the first valve 2 to control the flow rate of liquid effluent from nuclear facilities, open the cold trap 4 and set the cold trap temperature to the first temperature value T1 through the temperature regulator 6, and the liquid effluent from nuclear facilities enters the interior of the bubbler 5 along the bypass monitoring pipe 3.

[0050] Step 2: Start the air pump to begin bubbling: Open the second valve 13-1, the third valve 13-2, the fourth valve 13-3 and the fifth valve 13-4 installed on the exhaust pipe 16, and start the air pump 11 to begin bubbling. Adjust the opening of the second valve 13-1, the third valve 13-2, the fourth valve 13-3 and the fifth valve 13-4 respectively so that a set volume of gas remains above the liquid surface in the bubbler 5, and the outlet end of the air inlet pipe 7 extends below the liquid surface in the bubbler 5.

[0051] Step 3: Measure the liquid temperature inside the bubbler: Use thermometer 14 to measure the liquid temperature inside the bubbler 5 in real time;

[0052] Step 4: Obtain the liquid tritium concentration within the first temperature range: Observe the real-time reading T1' of thermometer 14. When |T1-T1'| < 0.1, start recording the temperature of gaseous tritium concentration measuring instrument 15 within the first temperature range T1. According to the readings of the gaseous tritium concentration measuring instrument 15 Back-calculation of liquid tritium water concentration within the first temperature range T1

[0053] The temperature readings of the gaseous tritium concentration measuring instrument 15 were recorded multiple times within the range of the first temperature value T1. And respectively, the concentration of liquid tritium water within multiple first temperature values ​​T1 ranges was calculated. Using multiple reverse deductions The average value is taken as the final liquid tritium water concentration within the first temperature range T1.

[0054] Step 5: Obtain the liquid tritium concentration within the second temperature range: Set the cold trap temperature to the second temperature value T2 using the temperature regulator 6. The second temperature value T2 is higher than the first temperature value T1. Observe the real-time reading T2' of the thermometer 14. When |T2-T2'| < 0.1, begin recording the temperature reading of the gaseous tritium concentration measuring instrument 15 within the second temperature range T2. According to the readings of the gaseous tritium concentration measuring instrument 15 Back-calculation of liquid tritium water concentration within the range of the second temperature value T2

[0055] The temperature readings of the gaseous tritium concentration measuring instrument 15 were recorded multiple times within the range of the second temperature value T2. And respectively, the concentration of liquid tritium water within multiple second temperature values ​​T2 ranges was calculated. Using multiple reverse deductions The average value is taken as the final liquid tritium concentration within the second temperature range T2.

[0056] Step 6: Obtain the liquid tritium water concentration within the next temperature range: Set the cold trap temperature to the nth temperature value T using temperature regulator 6. n Wherein, the nth temperature value T n Higher than the (n-1)th temperature value T n-1 n is a positive integer greater than 2. Observe the real-time reading T of thermometer 14. n ',When|T n -T n After | < 0.1, start recording the nth temperature value T. nThe reading of the gaseous tritium concentration measuring instrument 15 within the range According to the readings of the gaseous tritium concentration measuring instrument 15 Back-calculation of the nth temperature value T n Liquid tritium concentration within the range

[0057] Record the nth temperature value T multiple times n The reading of the gaseous tritium concentration measuring instrument 15 within the range And respectively deduce multiple nth temperature values ​​T n Liquid tritium concentration within the range Using multiple reverse deductions The average value is taken as the nth temperature value T. n The final concentration of liquid tritium water within the range

[0058] Step 7: Repeat Step 6 multiple times until sampling is completed, and obtain the final liquid tritium concentration at N different temperatures, where N is the total number of temperature cycles set by temperature regulator 6.

[0059] Step 8: According to the formula Calculate the tritium concentration value A in the liquid effluent of the nuclear facility. G .

[0060] In this embodiment, the nth temperature value T n With the (n-1)th temperature value T n-1 The temperature difference between them is 1℃ to 3℃.

[0061] It should be noted that, based on the readings of the gaseous tritium concentration measuring instrument 15... Back-calculation of the nth temperature value T n Liquid tritium concentration within the range Using formula Conversely, m(T) represents the saturated water content per unit volume of gas produced by bubbling when the standard tritium water temperature in the bubbler 5 is T, expressed in g·m³. -3 As shown in Table 1; S is the saturation coefficient, reflecting the degree of saturation of standard tritium water vapor produced by the bubbler, and is dimensionless; V G Total volume of air entering the bubbler, in liters (L). The volume of tritium water entering the bubbler during the bubbling process is expressed in mL.

[0062] Table 1

[0063]

[0064] In this invention, the monitoring of liquid tritium in liquid effluents is transformed into the monitoring of gaseous tritium. The liquid tritium concentration is then calculated through reverse deduction, thereby achieving the goal of real-time online monitoring of tritium concentration in liquid effluents from nuclear facilities. This improves monitoring efficiency and accuracy. The online continuous monitoring method can detect tritium concentration in liquid effluents in real time and continuously, eliminating the need for frequent manual sampling. This not only improves monitoring efficiency but also reduces errors caused by human operation, thus improving data accuracy. It can also promptly detect anomalies. Through the online monitoring system, changes in tritium concentration during the operation of nuclear facilities can be continuously tracked, and any anomalies detected can be detected immediately. In the event of a sudden increase in tritium concentration, an early warning can be issued in the shortest possible time, reminding the user to take immediate emergency measures to prevent the situation from escalating and enhancing emergency response capabilities. In the event of a nuclear accident, it is necessary to continuously monitor the leakage of radioactive materials for a long period of time. Online monitoring systems can provide long-term data recording and analysis, helping decision-makers to better understand the development of the accident and formulate effective response strategies. To ensure the safety of employees and the public, the application of online continuous monitoring methods avoids the risk of leakage during sampling by operators and helps to monitor the radiation levels in liquid water around nuclear facilities in real time, ensuring public safety.

[0065] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A method for online monitoring of tritium concentration in liquid effluents of nuclear facilities, comprising using an online monitoring device for tritium concentration in liquid effluents of nuclear facilities, characterized in that: The online monitoring device for tritium concentration in liquid effluent of the nuclear facility includes a bypass monitoring pipe (3) installed beside the effluent discharge pipe (1) of the nuclear facility. Both ends of the bypass monitoring pipe (3) are connected to the effluent discharge pipe (1) of the nuclear facility. A tritized water vapor generator is connected to the bypass monitoring pipe (3). The output end of the tritized water vapor generator is connected to a gaseous tritium concentration measuring instrument (15) through a gas supply pipe (10). The output end of the gaseous tritium concentration measuring instrument (15) is connected to the effluent discharge pipe (1) of the nuclear facility through an exhaust pipe (16). The signal output end of the gaseous tritium concentration measuring instrument (15) communicates with the monitoring terminal. The tritium vapor generator includes a bubbler (5) connected to a bypass monitoring pipe (3). The bubbler (5) is wrapped with a cold trap (4) and is in physical contact with the cold trap (4). A thermometer (14) for measuring the temperature of liquid effluent from the nuclear facility is installed on the bubbler (5). A temperature regulator (6) for adjusting the temperature inside the cold trap (4) is installed on the cold trap (4). An inlet pipe (7) is installed at the input end of the bubbler (5). A drying bottle (9), a third valve (13-2), a gas pump (11), and a gas flow meter (12) are installed sequentially on the inlet pipe (7). A gas take-up pipe (8) is connected to the input end of the drying bottle (9). A second valve (13-1) is installed on the gas take-up pipe (8). The inlet end of the gas supply pipe (10) is connected to the output end of the bubbler (5), and a fourth valve (13-3) is installed on the gas supply pipe (10). The method includes the following steps: Step 1: Collect liquid effluent from the nuclear facility: Adjust the opening of the first valve (2) to control the flow rate of the liquid effluent from the nuclear facility, open the cold trap (4), and set the cold trap temperature to the first temperature value through the temperature regulator (6). Liquid effluent from the nuclear facility enters the interior of the bubbler (5) along the bypass monitoring pipe (3); Step 2: Start the air pump to begin bubbling: Open the second valve (13-1), the third valve (13-2), the fourth valve (13-3), and the fifth valve (13-4) installed on the exhaust pipe (16), and start the air pump (11) to begin bubbling. Adjust the opening of the second valve (13-1), the third valve (13-2), the fourth valve (13-3), and the fifth valve (13-4) respectively so that a set volume of gas remains above the liquid surface in the bubbler (5), and the outlet end of the air inlet pipe (7) extends below the liquid surface in the bubbler (5); Step 3: Measure the liquid temperature inside the bubbler: Use a thermometer (14) to measure the liquid temperature inside the bubbler (5) in real time; Step 4: Obtain the concentration of liquid tritium water within the first temperature range: Observe the real-time reading of the thermometer (14). ,when Then, the first temperature value was recorded. The reading of the gaseous tritium concentration measuring instrument (15) within the range According to the reading of the gaseous tritium concentration measuring instrument (15) Back-derive the first temperature value Liquid tritium concentration within the range ; Record the first temperature value multiple times The reading of the gaseous tritium concentration measuring instrument (15) within the range And respectively, reverse-engineer multiple first temperature values. Liquid tritium concentration within the range Using multiple reverse deductions The average value is used as the first temperature value. The final concentration of liquid tritium water within the range ; Step 5: Obtain the concentration of liquid tritium water within the second temperature range: Set the cold trap temperature to the second temperature value using the temperature regulator (6). Among them, the second temperature value Higher than the first temperature value Observe the real-time reading of the thermometer (14). ,when Then, the second temperature value was recorded. The reading of the gaseous tritium concentration measuring instrument (15) within the range According to the reading of the gaseous tritium concentration measuring instrument (15) Reverse calculation of the second temperature value Liquid tritium concentration within the range ; Record the second temperature value multiple times The reading of the gaseous tritium concentration measuring instrument (15) within the range And respectively, multiple second temperature values ​​were deduced. Liquid tritium concentration within the range Using multiple reverse deductions The average value is used as the second temperature value. The final concentration of liquid tritium water within the range ; Step 6: Obtain the liquid tritium concentration within the next temperature range: Set the cold trap temperature to the nth temperature value using the temperature regulator (6). , where the nth temperature value Higher than the (n-1)th temperature value n is a positive integer greater than 2. Observe the real-time reading of the thermometer (14). ,when Then, begin recording the nth temperature value. The reading of the gaseous tritium concentration measuring instrument (15) within the range According to the reading of the gaseous tritium concentration measuring instrument (15) Back-calculation of the nth temperature value Liquid tritium concentration within the range ; Record the nth temperature value multiple times The reading of the gaseous tritium concentration measuring instrument (15) within the range And respectively deduce multiple nth temperature values. Liquid tritium concentration within the range Using multiple reverse deductions The average value is used as the nth temperature value. The final concentration of liquid tritium water within the range ; Step 7: Repeat Step 6 multiple times until sampling is completed, and obtain the final liquid tritium concentration at N different temperatures, where N is the total number of temperature cycles set by the temperature regulator (6). Step 8: According to the formula Calculate the tritium concentration in liquid effluent from a nuclear facility. .

2. The method for online monitoring of tritium concentration in liquid effluents from a nuclear facility according to claim 1, characterized in that: Both ends of the bypass monitoring pipeline (3) are equipped with a first valve (2).

3. A method for online monitoring of tritium concentration in liquid effluent from a nuclear facility according to claim 1, characterized in that: The exhaust pipe (16) is equipped with a fifth valve (13-4).

4. A method for online monitoring of tritium concentration in liquid effluent from a nuclear facility according to claim 1, characterized in that: The gaseous tritium concentration measuring instrument (15) is installed at a height higher than the nuclear facility effluent discharge pipe (1) to prevent liquid effluent from the nuclear facility from entering the gaseous tritium concentration measuring instrument (15).

5. A method for online monitoring of tritium concentration in liquid effluent from a nuclear facility according to claim 1, characterized in that: The nth temperature value With the (n-1)th temperature value The temperature difference between them is 1℃ to 3℃.

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