阅读说明：本技术 一种高湿度惰性气体活度监测系统及监测方法 (High-humidity inert gas activity monitoring system and monitoring method ) 是由 陈禹轩 曲广卫 马兴杰 刘朋波 胡卓 聂世宾 杨中中 石建伟 于 2021-06-25 设计创作，主要内容包括：本发明公开了一种高湿度惰性气体活度监测系统及监测方法,系统包括惰性气体取样组件和测控组件,惰性气体取样组件包括取样管路,取样管路上随进气方向依次设置有汽水分离机构、气溶胶与碘过滤机构、气体流量计、惰性气体取样室和气体取样泵,测控组件包括惰性气体探测器和就地辐射处理单元,以及与就地辐射处理单元相接的电气控制箱,惰性气体探测器设置在惰性气体取样室上侧,且与就地辐射处理单元的输入端连接。本发明系统结构简单,设计合理,能够有效应用在高湿度惰性气体活度监测中,结合监测方法,实现对惰性气体中～(85)Kr、～(133)Xe核素的β总活度浓度探测,进而判断蒸汽发生器的泄漏情况,性能稳定,效率高,效果显著,便于推广。(The invention discloses a high-humidity inert gas activity monitoring system and a monitoring method, wherein the system comprises an inert gas sampling assembly and a measurement and control assembly, the inert gas sampling assembly comprises a sampling pipeline, a steam-water separation mechanism, an aerosol and iodine filtering mechanism, a gas flowmeter, an inert gas sampling chamber and a gas sampling pump are sequentially arranged on the sampling pipeline along the air inlet direction, the measurement and control assembly comprises an inert gas detector, an in-situ radiation processing unit and an electric control box connected with the in-situ radiation processing unit, and the inert gas detector is arranged on the upper side of the inert gas sampling chamber and connected with the input end of the in-situ radiation processing unit. The system has simple structure and reasonable design, can be effectively applied to the activity monitoring of the high-humidity inert gas, and is combined with the monitoring method to realize the purpose of monitoring the activity of the inert gas 85 Kr、 133 The beta total activity concentration of Xe nuclide is detected, so that the leakage condition of the steam generator is judged, and the performance is stableHigh efficiency, obvious effect and convenient popularization.)

1. A high humidity inert gas activity monitoring system characterized in that: including inert gas sampling subassembly and observing and controling subassembly, inert gas sampling subassembly includes sampling pipeline, set gradually vapour-water separation mechanism (1), aerosol and iodine filtering mechanism (2), gas flowmeter (3), inert gas sampling chamber (4) and gas sampling pump (5) along with the direction of admitting air on the sampling pipeline, observe and control the subassembly and include inert gas detector (6) and radiation processing unit (7) on the spot to and electric control box (8) that meet with radiation processing unit (7) on the spot, inert gas detector (6) set up at inert gas sampling chamber (4) upside, and are connected with the input of radiation processing unit (7) on the spot, gas sampling pump (5) are connected with the output of electric control box (8).

2. A high humidity inert gas activity monitoring system according to claim 1, wherein: the steam-water separation mechanism (1) comprises a support (1-1), a dehumidification tank (1-2), a liquid storage tank (1-3), a refrigerator (1-4), a circulating pump (1-16) and a controller (1-5) are arranged on the support (1-1), an air inlet pipe (1-6) and an air outlet pipe (1-7) are connected to the dehumidification tank (1-2), and a low-temperature water temperature sensor (1-8) and a spiral coil pipe extending into the low-temperature water are arranged in the dehumidification tank (1-2); the spiral coil is connected with a refrigerator (1-4), cooling liquid is arranged in the spiral coil, the cooling liquid circulates between the spiral coil and the refrigerator (1-4) through a circulating pump (1-16) and is refrigerated through the refrigerator (1-4), a gas outlet of the gas inlet pipe (1-6) is arranged at the bottom of low-temperature water, an electric heating belt is wound on the gas outlet pipe (1-7), an overflow pipe (1-9) is connected between the dehumidification tank (1-2) and the liquid storage tank (1-3), a first electromagnetic valve (1-10) is arranged on the overflow pipe (1-9), a vent pipe (1-11) is connected on the liquid storage tank (1-3), and a second electromagnetic valve (1-12) is arranged on the vent pipe (1-11), the refrigerator is characterized in that liquid level sensors (1-13) are arranged in the liquid storage tanks (1-3), liquid discharge pipes (1-14) are arranged at the bottoms of the liquid storage tanks (1-3), third electromagnetic valves (1-15) are arranged on the liquid discharge pipes (1-14), the temperature sensors (1-8) and the liquid level sensors (1-13) are connected with the input ends of controllers (1-5), and the refrigerators (1-4), the first electromagnetic valves (1-10), the second electromagnetic valves (1-12) and the third electromagnetic valves (1-15) are connected with the output ends of the controllers (1-5).

3. A high humidity inert gas activity monitoring system according to claim 1, wherein: the aerosol and iodine filtering mechanism (2) comprises a first aerosol and iodine filtering pipeline and a second aerosol and iodine filtering pipeline, the first aerosol and iodine filtering pipeline comprises a first valve (2-1), a first aerosol and iodine filter (2-2) and a second valve (2-3) which are sequentially arranged along the air inlet direction, the second aerosol and iodine filtering pipeline comprises a third valve (2-4), a second aerosol and iodine filter (2-5) and a fourth valve (2-6) which are sequentially arranged along the air inlet direction, and the first aerosol and iodine filtering pipeline and the second aerosol and iodine filtering pipeline are identical in structure and redundant mutually.

4. A high humidity inert gas activity monitoring system according to claim 1, wherein: the inert gas sampling chamber (4) is a sealed chamber with the volume of 3L-4L.

5. A high humidity inert gas activity monitoring system according to claim 1, wherein: the gas sampling pump (5) provides sampling power for the inert gas sampling assembly.

6. A high humidity inert gas activity monitoring system according to claim 1, wherein: inert gas detector (6) set up the upside in inert gas sampling room (4), inert gas detector (6) include plastic scintillator (6-1), organic glass light guide (6-2) and photomultiplier (6-3) that set gradually from bottom to top, photomultiplier (6-3)'s output is connected with signal processing circuit module (6-4), signal processing circuit module (6-4) are connected with the input of radiation processing unit (7) on the spot.

7. A high humidity inert gas activity monitoring system according to claim 1, wherein: and the inert gas sampling chamber (4) and the inert gas detector (6) are both arranged in the lead shielding chamber.

8. A high humidity inert gas activity monitoring system according to claim 1, wherein: the local radiation processing unit (7) comprises a microcontroller module (7-1), an RS485 interface (7-2) and an Ethernet interface (7-3), wherein the RS485 interface and the Ethernet interface are connected with the microcontroller module (7-1), the input end of the microcontroller module (7-1) is connected with a key input module (7-4), and the output end of the microcontroller module (7-1) is connected with a display module (7-5) and an acousto-optic alarm module (7-6).

9. A high humidity inert gas activity monitoring system according to claim 1, wherein: the electrical control box (8) provides power to the gas sampling pump (5) and the in situ radiation processing unit (7), as well as input and output terminals.

10. A method for high humidity inert gas activity monitoring using the system of claim 1, comprising the steps of:

step one, the electrical control box (8) controls the power supply of the gas sampling pump (5) to be electrified;

step two, the gas sampling pump (5) works to provide sampling power for the inert gas sampling assembly;

step three, the steam-water separation mechanism (1) performs steam-water separation and dehumidification treatment on the sampled gas;

fourthly, the aerosol and iodine filtering mechanism (2) filters aerosol, iodine and particulate matters in the sampling gas;

fifthly, the inert gas detector (6) samples the inert gas entering the inert gas sampling chamber (4)⁸⁵Kr and¹³³detecting the total activity concentration of the Xe species and transmitting the detection result to an in-situ radiation processing unit (7);

and step six, the local radiation processing unit (7) processes and displays the detection result, and sends out a corresponding alarm signal when the detection result exceeds a preset threshold value.

Technical Field

The invention belongs to the technical field of nuclear radiation monitoring, and particularly relates to a high-humidity inert gas activity monitoring system and a monitoring method.

Background

In order to protect the personnel and public places of the nuclear power plant from radioactive emissions, the nuclear power plant is provided with a radiation monitoring system (abbreviated as KRT system) for continuously monitoring the nuclear power plant area and airborne suspended matter, as well as the nuclear power plant process and the radioactivity of effluents.

A nuclear power plant of a pressurized water reactor nuclear power plant is generally composed of two closed circulation loops, called a primary loop and a secondary loop, the primary loop includes a nuclear reactor (sealed in a pressure vessel), a main coolant pump, a pressurizer and other devices, the secondary loop includes a steam generator, a condenser, a main coolant pump and other devices, and the primary loop is connected to the reactor core and the steam generator in the secondary loop. After absorbing the heat energy of the cooling water in the first loop, the cooling water in the second loop is heated to boiling (the temperature is about 260 ℃) to form steam, and the steam is filtered to remove mixed liquid water and then is sent to a steam turbine to push a turbine engine to operate to generate electricity. The cooling water of the two loops flowing out from the steam turbine is condensed into liquid water by the condenser and then flows back to the steam generator.

Inert gas activity monitor for monitoring inert gas in non-condensed extract extracted from condenser⁸⁵Kr、¹³³The total activity concentration of beta activity of Xe is used to determine the leak condition of the steam generator.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide a high humidity inert gas activity monitoring system for overcoming the above disadvantages in the prior artThe system has simple structure, reasonable design and convenient realization, can be effectively applied to the activity monitoring of the high-humidity inert gas, and is combined with the monitoring method to realize the monitoring of the activity of the inert gas⁸⁵Kr、¹³³The beta total activity concentration of the Xe nuclide is detected, so that the leakage condition of the steam generator is judged, and the method has the advantages of stable performance, high efficiency, obvious effect and convenience in popularization.

In order to solve the technical problems, the invention adopts the technical scheme that: the utility model provides a high humidity inert gas activity monitoring system, includes inert gas sampling subassembly and observes and controls the subassembly, inert gas sampling subassembly includes the sampling pipeline, steam-water separation mechanism, aerosol and iodine filtering mechanism, gas flowmeter, inert gas sampling chamber and gas sampling pump have set gradually along with the direction of admitting air on the sampling pipeline, observe and control the subassembly and include inert gas detector and radiation processing unit on the spot to and the electric control box that meets with radiation processing unit on the spot, inert gas detector sets up at inert gas sampling chamber upside, and is connected with radiation processing unit on the spot's input, gas sampling pump is connected with electric control box's output.

The system for monitoring the activity of the high-humidity inert gas comprises a support, wherein a dehumidification tank, a liquid storage tank, a refrigerator, a circulating pump and a controller are arranged on the support, an air inlet pipe and an air outlet pipe are connected to the dehumidification tank, and a temperature sensor for detecting the temperature of low-temperature water and a spiral coil pipe extending into the low-temperature water are arranged in the dehumidification tank; the spiral coil is connected with the refrigerator, cooling liquid is arranged in the spiral coil and circulates between the spiral coil and the refrigerator through a circulating pump, and is refrigerated by a refrigerator, the gas outlet of the gas inlet pipe is arranged at the bottom of the low-temperature water, the gas outlet pipe is wound with an electric heating belt, an overflow pipe is connected between the dehumidification tank and the liquid storage tank, a first electromagnetic valve is arranged on the overflow pipe, the liquid storage tank is connected with a breather pipe, the breather pipe is provided with a second electromagnetic valve, the liquid storage tank is internally provided with a liquid level sensor, a liquid discharge pipe is arranged at the bottom of the liquid storage tank, a third electromagnetic valve is arranged on the liquid discharge pipe, the temperature sensor and the liquid level sensor are both connected with the input end of the controller, the refrigerator, the first electromagnetic valve, the second electromagnetic valve and the third electromagnetic valve are all connected with the output end of the controller.

Foretell high humidity inert gas activity monitoring system, aerosol and iodine filtering mechanism include first aerosol and iodine filtering line and second aerosol and iodine filtering line, first aerosol and iodine filtering line include first valve, first aerosol and iodine filter and the second valve that sets gradually along with the direction of admitting air, second aerosol and iodine filter and fourth valve that second aerosol and iodine filtering line include the third valve, second aerosol and iodine filter and the fourth valve that set gradually along with the direction of admitting air, first aerosol and iodine filtering line are the same with second aerosol and iodine filtering line structure and are each other redundant.

In the high-humidity inert gas activity monitoring system, the inert gas sampling chamber is a sealed chamber with a volume of 3L-4L.

In the above high-humidity inert gas activity monitoring system, the gas sampling pump provides sampling power for the inert gas sampling assembly.

Foretell high humidity inert gas activity monitoring system, the inert gas detector sets up the upside at inert gas sampling chamber, the inert gas detector includes plastics scintillator, organic glass light guide and the photomultiplier that from bottom to top sets gradually, photomultiplier's output is connected with signal processing circuit module, signal processing circuit module is connected with the input of radiation processing unit on the spot.

According to the high-humidity inert gas activity monitoring system, the inert gas sampling chamber and the inert gas detector are both arranged in the lead shielding chamber.

Foretell high humidity inert gas activity monitoring system, the processing unit that radiates on spot includes microcontroller module to and RS485 interface and the ethernet interface that meets with microcontroller module, microcontroller module's input termination has button input module, microcontroller module's output termination has display module and acousto-optic warning module.

In the high-humidity inert gas activity monitoring system, the electrical control box provides power for the gas sampling pump and the in-situ radiation processing unit, and provides an input wiring terminal and an output wiring terminal.

The invention also discloses a method for monitoring the activity of the high-humidity inert gas by adopting the system, which comprises the following steps:

step one, the electrical control box controls a power supply of the gas sampling pump to be electrified;

step two, the gas sampling pump works to provide sampling power for the inert gas sampling assembly;

step three, the steam-water separation mechanism performs steam-water separation and dehumidification treatment on the sampled gas;

fourthly, filtering aerosol, iodine and particulate matters in the sampling gas by the aerosol and iodine filtering mechanism;

step five, the inert gas detector is used for detecting the inert gas entering the inert gas sampling chamber⁸⁵Kr and¹³³detecting the total activity concentration of the Xe nuclide and transmitting the detection result to the in-situ radiation processing unit;

and step six, the local radiation processing unit processes and displays the detection result, and sends out a corresponding alarm signal when the detection result exceeds a preset threshold value.

Compared with the prior art, the invention has the following advantages:

1. the system of the invention has simple structure, reasonable design and convenient realization.

2. The invention designs a steam-water separation mechanism to dehumidify the high-humidity inert gas before entering the monitoring system, so that the phenomenon that when the high-humidity inert gas to be measured enters the monitoring system, because the temperature in the monitoring system is equal to the ambient temperature and is mostly on the surface of stainless steel metal, water in the high-humidity inert gas to be measured condenses when meeting cold, water in the monitoring system is accumulated, and the measurement result is influenced is avoided.

3. The invention designs an aerosol and iodine filtering mechanism, wherein the dehumidified inert gas firstly filters aerosol and particulate matters through aerosol and iodine filtering paper in the aerosol and iodine filtering mechanism, and then an active carbon box is adopted to adsorb radioactive iodine in the inert gas, so that the situation that the aerosol and the gaseous radioactive iodine enter an inert gas sampling chamber to influence a detection result is avoided.

4. The first aerosol and iodine filtering pipeline and the second aerosol and iodine filtering pipeline which are the same in aerosol and iodine filtering mechanism design structure are redundant and work separately, one pipeline is completely closed when the other pipeline works, and the filter paper and the iodine box can be replaced when the other pipeline is closed, so that the whole system can be ensured to operate uninterruptedly, and the efficiency is improved.

5. The invention can be effectively applied to the activity monitoring of the high-humidity inert gas and realizes the monitoring of the activity of the inert gas in the inert gas by combining the monitoring method⁸⁵Kr、¹³³The beta total activity concentration of the Xe nuclide is detected, so that the leakage condition of the steam generator is judged, and the method has the advantages of stable performance, high efficiency, obvious effect and convenience in popularization.

In conclusion, the system disclosed by the invention is simple in structure, reasonable in design and convenient to realize, can be effectively applied to the activity monitoring of the high-humidity inert gas, and is combined with a monitoring method to realize the monitoring of the activity of the inert gas in the inert gas⁸⁵Kr、¹³³The beta total activity concentration of the Xe nuclide is detected, so that the leakage condition of the steam generator is judged, and the method has the advantages of stable performance, high efficiency, obvious effect and convenience in popularization.

The technical solution of the present invention is further described in detail by the accompanying drawings and embodiments.

Drawings

FIG. 1 is a schematic block diagram of the system of the present invention;

FIG. 2 is a schematic structural view of a steam-water separation mechanism according to the present invention;

FIG. 3 is a functional block diagram of the aerosol and iodine filter mechanism of the present invention;

FIG. 4 is a schematic block diagram of an inert gas detector of the present invention;

FIG. 5 is a schematic block diagram of an in situ radiation processing unit of the present invention;

FIG. 6 is a flow chart of a method of the present invention.

Description of reference numerals:

1-steam-water separation mechanism; 1-scaffold; 1-2-a dehumidification tank;

1-3-a liquid storage tank; 1-4-refrigerator; 1-5-a controller;

1-6 parts of an air inlet pipe; 1-7-air outlet pipe; 1-8-temperature sensor;

1-9-overflow pipe; 1-10-a first solenoid valve; 1-11-a vent pipe;

1-12-second electromagnetic valve; 1-13-level sensor; 1-14-drain;

1-15-third electromagnetic valve; 1-16-circulation pump; 2-aerosol and iodine filtering mechanism;

2-1 — a first valve; 2-2 — a first aerosol and iodine filter; 2-3 — a second valve;

2-4-a third valve; 2-5-second aerosol and iodine filter; 2-6-fourth valve;

3-a gas flow meter; 4-inert gas sampling chamber; 5-a gas sampling pump;

6-inert gas detector; 6-1-plastic scintillator; 6-2-plexiglas lightguide;

6-3-photomultiplier tube; 6-4-signal processing circuit module; 7-in-situ radiation treatment unit;

7-1 — a microcontroller module; 7-2-RS 485 interface; 7-3-ethernet interface;

7-4-key input module; 7-5-a display module; 7-6, a sound and light alarm module;

8, an electric control box.

Detailed Description

As shown in fig. 1, the high-humidity inert gas activity monitoring system comprises an inert gas sampling assembly and a measurement and control assembly, wherein the inert gas sampling assembly comprises a sampling pipeline, a steam-water separation mechanism 1, an aerosol and iodine filtering mechanism 2, a gas flowmeter 3, an inert gas sampling chamber 4 and a gas sampling pump 5 are sequentially arranged on the sampling pipeline along the air inlet direction, the measurement and control assembly comprises an inert gas detector 6, an in-situ radiation processing unit 7 and an electric control box 8 connected with the in-situ radiation processing unit 7, the inert gas detector 6 is arranged on the upper side of the inert gas sampling chamber 4 and is connected with the input end of the in-situ radiation processing unit 7, and the gas sampling pump 5 is connected with the output end of the electric control box 8.

In this embodiment, as shown in fig. 2, the steam-water separation mechanism 1 includes a support 1-1, a dehumidification tank 1-2, a liquid storage tank 1-3, a refrigerator 1-4, a circulation pump 1-16 and a controller 1-5 are disposed on the support 1-1, an air inlet pipe 1-6 and an air outlet pipe 1-7 are connected to the dehumidification tank 1-2, and a low-temperature water temperature sensor 1-8 and a spiral coil pipe extending into the low-temperature water are disposed in the dehumidification tank 1-2; the spiral coil is connected with a refrigerator 1-4, cooling liquid is arranged in the spiral coil, the cooling liquid circulates between the spiral coil and the refrigerator 1-4 through a circulating pump 1-16 and is refrigerated through the refrigerator 1-4, a gas outlet of the gas inlet pipe 1-6 is arranged at the bottom of low-temperature water, an electric heating belt is wound on the gas outlet pipe 1-7, an overflow pipe 1-9 is connected between the dehumidification tank 1-2 and the liquid storage tank 1-3, a first electromagnetic valve 1-10 is arranged on the overflow pipe 1-9, a vent pipe 1-11 is connected on the liquid storage tank 1-3, a second electromagnetic valve 1-12 is arranged on the vent pipe 1-11, a liquid level sensor 1-13 is arranged in the liquid storage tank 1-3, a liquid discharge pipe 1-14 is arranged at the bottom of the liquid storage tank 1-3, the liquid discharge pipe 1-14 is provided with a third electromagnetic valve 1-15, the temperature sensor 1-8 and the liquid level sensor 1-13 are connected with the input end of the controller 1-5, and the refrigerator 1-4, the first electromagnetic valve 1-10, the second electromagnetic valve 1-12 and the third electromagnetic valve 1-15 are connected with the output end of the controller 1-5.

In specific implementation, the temperature sensors 1-8 detect the temperature of the low-temperature water in the dehumidification tanks 1-2 in real time, when the temperature of the low-temperature water is higher than 10 ℃, the controller 1-5 controls the circulating pumps 1-16 to start, the chilled cooling liquid in the refrigerators 1-4 is circulated to the spiral coil pipe, and the low-temperature water is cooled; when the temperature of the low-temperature water is lower than 5 ℃, the controller 1-5 controls the circulating pump 1-16 to stop working.

High-humidity inert gas enters the bottom of the dehumidifying tank 1-2 through the gas inlet pipe 1-6 and is fully mixed with the low-temperature water in the dehumidifying tank 1-2, water in the high-humidity inert gas is mixed in the low-temperature water, the inert gas is discharged through the gas outlet pipe 1-7 after being cooled to be low-temperature gas at about 5 ℃, in the discharging process, the inert gas is heated to about 35 ℃ under the action of an electric heating belt on the gas outlet pipe 1-7, the humidity of the inert gas is reduced at the moment, and the steam-water separation is realized.

During the working process of the steam-water separation mechanism 1, the liquid level in the dehumidification tank 1-2 gradually rises, when the liquid level reaches the set height of the overflow pipe 1-9, the liquid flows into the liquid storage tank 1-3 through the overflow pipe 1-9, at the moment, the first electromagnetic valve 1-10 is in an open state, the liquid level sensor 1-13 in the liquid storage tank 1-3 detects the liquid level height in the liquid storage tank 1-3 in real time, when the preset value is reached, the controller 1-5 controls the second electromagnetic valve 1-12 and the third electromagnetic valve 1-15 to be opened, and controls the first electromagnetic valve 1-10 to be closed, so that the liquid in the liquid storage tank 1-3 is discharged through the liquid discharge pipe 1-14.

In this embodiment, as shown in fig. 3, the aerosol and iodine filtering mechanism 2 includes a first aerosol and iodine filtering pipeline and a second aerosol and iodine filtering pipeline, the first aerosol and iodine filtering pipeline includes a first valve 2-1, a first aerosol and iodine filter 2-2, and a second valve 2-3 that are sequentially arranged along an air intake direction, the second aerosol and iodine filtering pipeline includes a third valve 2-4, a second aerosol and iodine filter 2-5, and a fourth valve 2-6 that are sequentially arranged along the air intake direction, and the first aerosol and iodine filtering pipeline and the second aerosol and iodine filtering pipeline have the same structure and are redundant to each other.

During specific implementation, the first valve 2-1, the second valve 2-3, the third valve 2-4 and the fourth valve 2-6 are manual valves, the first aerosol and iodine filtering pipeline and the second aerosol and iodine filtering pipeline work separately, one pipeline works, the other pipeline is completely closed, the other pipeline in the closing process can be completely closed, filter paper replacement and iodine box replacement can be carried out on the closed pipeline, therefore, the whole system can be ensured to operate uninterruptedly, and the two pipelines are switched through the manual valves.

In this embodiment, the inert gas sampling chamber 4 is a sealed chamber having a volume of 3L to 4L.

In practice, the volume of the inert gas sampling chamber 4 is about 3.47L.

In this embodiment, the gas sampling pump 5 provides sampling power for the inert gas sampling assembly.

In this embodiment, the inert gas detector 6 is disposed on the upper side of the inert gas sampling chamber 4, as shown in fig. 4, the inert gas detector 6 includes a plastic scintillator 6-1, an organic glass light guide 6-2, and a photomultiplier tube 6-3, which are sequentially disposed from bottom to top, an output end of the photomultiplier tube 6-3 is connected to a signal processing circuit module 6-4, and the signal processing circuit module 6-4 is connected to an input end of the local radiation processing unit 7.

In specific implementation, the plastic scintillator 6-1 adopts a beta plastic scintillator, the thickness of the beta plastic scintillator is 0.5 mm-1 mm, and the detection area is about 300cm²The large-area plastic scintillator is adopted, so that the counting rate of beta rays can be increased, the detection efficiency is improved, and the detection lower limit is reduced; in order to improve the strength and the light absorption efficiency of the beta plastic scintillator, an organic glass light guide 6-2 with the thickness of 10mm is tightly attached to the back of the beta plastic scintillator; the photomultiplier 6-3 is arranged at the central position of the organic glass light guide 6-2; the signal processing circuit module 6-4 comprises two circuit boards, one of which is used for carrying out pre-amplification, discrimination and formed current integration and voltage-frequency conversion on the signal of the photomultiplier tube 6-3, and the other is used for pulse counting, data acquisition and external communication.

In this embodiment, the inert gas sampling chamber 4 and the inert gas detector 6 are both disposed in a lead shielding chamber.

In specific implementation, in order to reduce the influence of external gamma rays, reduce background counting and improve low-radioactivity detection capability, the inert gas sampling chamber 4 and the inert gas detector 6 are both arranged in a 4 pi lead shielding chamber.

In this embodiment, as shown in fig. 5, the local radiation processing unit 7 includes a microcontroller module 7-1, and an RS485 interface 7-2 and an ethernet interface 7-3 connected to the microcontroller module 7-1, an input end of the microcontroller module 7-1 is connected to a key input module 7-4, and an output end of the microcontroller module 7-1 is connected to a display module 7-5 and an audible and visual alarm module 7-6.

During specific implementation, the in-situ radiation processing unit 7 is connected with and communicates with the inert gas detector 6 through the RS485 interface 7-2, data processing of the activity concentration of the inert gas is completed through the microcontroller module 7-1, display is performed through the display module 7-5, when the activity concentration exceeds an alarm threshold value, an acousto-optic alarm signal is sent out through the acousto-optic alarm module 7-6, and the alarm signal is transmitted to the main control room through the Ethernet interface 7-3 or the RS485 interface 7-2.

In this embodiment, the electrical control box 8 provides power to the gas sampling pump 5 and the in situ radiation processing unit 7, as well as input and output terminals.

During specific implementation, the input wiring terminal comprises 4-20 mA analog input (external flow signal and temperature), and the output wiring terminal comprises 4-20 mA output (measurement result) and switch output (fault/failure, test/source detection, high-value alarm and high-value alarm) and RS485 communication (measurement result and control).

As shown in fig. 6, the method for monitoring activity of high humidity inert gas of the present invention comprises the following steps:

step one, the electrical control box 8 controls the power supply of the gas sampling pump 5 to be electrified;

step two, the gas sampling pump 5 works to provide sampling power for the inert gas sampling assembly;

step three, the steam-water separation mechanism 1 carries out steam-water separation and dehumidification treatment on the sampled gas;

in specific implementation, when the high-humidity inert gas to be detected enters the monitoring system, because the temperature in the monitoring system is equal to the ambient temperature and is mostly on the surface of stainless steel metal, water in the high-humidity inert gas to be detected is easy to condense when meeting cold, so that water is accumulated in the monitoring system and the measurement is influenced, and therefore, the high-humidity inert gas needs to be subjected to dehumidification before entering the monitoring system; introducing high-humidity inert gas into water in cold trap, separating water from gas, cooling to 5 deg.C, and adding 6.79g/m water when relative humidity is 100% at 5 deg.C³The gas, when heated to 35 ℃ at the rear end, contained 6.79g/m of water³The relative humidity is less than 20%.

Fourthly, the aerosol and iodine filtering mechanism 2 filters aerosol, iodine and particulate matters in the sampling gas;

in specific implementation, the dehumidified inert gas firstly passes through the aerosol and iodine filter paper in the aerosol and iodine filter mechanism 2 to filter aerosol and particulate matters, and then the active carbon box is adopted to adsorb radioactive iodine (methyl iodide and elemental iodine) in the inert gas; so as to prevent the aerosol and the gaseous radioactive iodine from entering the inert gas sampling chamber to influence the detection result;

step five, the inert gas detector 6 is used for detecting the inert gas entering the inert gas sampling chamber 4⁸⁵Kr and¹³³the beta total activity concentration of the Xe species is detected and the detection result is transmitted to the in-situ radiation processing unit 7;

and step six, the local radiation processing unit 7 processes and displays the detection result, and sends out a corresponding alarm signal when the detection result exceeds a preset threshold value.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and all simple modifications, changes and equivalent structural changes made to the above embodiment according to the technical spirit of the present invention still fall within the protection scope of the technical solution of the present invention.