CN219039369U - Radioactive gaseous iodine monitoring device - Google Patents

Abstract

The utility model discloses a radioactive gaseous iodine monitoring device, which belongs to the technical field of radioactive gas monitoring and comprises a vent pipe, wherein the vent pipe is sequentially communicated with a monitor, a flowmeter and an air pump, the monitor is electrically connected with a display device, the flowmeter, the air pump and the display device are electrically connected with an electric box. The utility model uses the self-carried gamma-radioactive lanthanum bromide scintillator as the radioactive iodine gamma-ray detection medium, which can solve the drift problem of peak position detected by the probe to a great extent.

Description

Radioactive gaseous iodine monitoring device

Technical Field

The utility model belongs to the technical field of radioactive gas monitoring, and particularly relates to a radioactive gaseous iodine monitoring device.

Background

The radioactive gaseous iodine continuous monitoring device is generally used for continuous monitoring of radioactive iodine activity concentration (Bq/m 3) in a nuclear facility, an isotopic iodine production or a gaseous effluent stream of a use site. The measuring principle of the monitoring device is as follows: the activity of the radioactive iodine is known by detecting gamma rays emitted by the radioactive iodine through a probe. The probe as a radioactive iodine detecting element mainly comprises two parts: sodium iodide scintillators and multipass. The existing continuous monitor for radioactive gaseous iodine generally uses a scintillator of a sodium iodide type as a detection medium of radioactive iodine gamma rays and uses a plurality of channels as a signal processing unit. The probe is influenced by factors such as temperature and circuit stability, radioactive iodine gamma rays are on a plurality of channels, and drift occurs at peak positions, so that analysis of the radioactive iodine signals by the plurality of channels is influenced. At this time, alpha rays emitted by an embedded reference source Am-241 are required to be used as energy references for peak position drift correction detected by a probe, and finally, gamma ray peak positions of iodine are stabilized on a plurality of specific channel addresses for convenient analysis.

The traditional method uses sodium iodide as a ray detection medium inside the probe, and uses an embedded Am-241 source as a peak stabilizing reference source. The embedded Am-241 source is influenced by an embedding process and environmental temperature in the sodium iodide crystal, so that the emitted alpha rays are different in the amplitude of the light pulse finally generated in the crystal, and after the light pulse is converted into an electric signal, the amplitude of the pulse obtained on a plurality of channels is changed, so-called peak position change occurs, and the change is peak position drift. Peak position drift can seriously affect the accuracy of the measurement.

Disclosure of Invention

The utility model aims to solve the technical problems in the prior art, and provides a radioactive gaseous iodine monitoring device which is provided with a vent pipe, wherein the vent pipe is sequentially communicated with a monitor, a flowmeter and an air pump, the monitor is electrically connected with a display device, and the flowmeter, the air pump and the display device are electrically connected with an electric box, and the radioactive gaseous iodine monitoring device is characterized in that the monitor comprises:

an iodine box communicated with the vent pipe;

the probe is arranged at the top of the iodine box, a lanthanum bromide scintillator is used as a detection medium of radioactive iodine gamma rays in the probe, and a lanthanum isotope La-133 in the lanthanum bromide scintillator is used as a peak stabilizing source for calibrating the peak position detected by the probe;

the multichannel energy spectrum analyzer is arranged at the top of the probe and is electrically connected with the display device.

Further, the method further comprises the following steps:

the filter is arranged on the breather pipe and is positioned between the air inlet and the iodine box.

Further, the method further comprises the following steps:

and the first stop valve is arranged on the vent pipe and is positioned between the air inlet and the filter.

Further, the method further comprises the following steps:

and one end of the purge pipe is connected with a vent pipe positioned between the air inlet and the first stop valve.

Further, the method further comprises the following steps:

the flow regulating valve is arranged on the vent pipe and is positioned between the air pump and the flowmeter.

Further, the method further comprises the following steps:

the second stop valve is arranged on the vent pipe and is positioned between the air outlet and the flow regulating valve.

Further, the method further comprises the following steps:

the fixing frame is used for fixing the vent pipe, the purging pipe, the monitor, the flowmeter, the air pump, the electric box and the display device.

Compared with the prior art, the utility model has the following advantages:

the probe of the utility model uses the self-carried gamma-radioactive lanthanum bromide scintillator as a radioactive iodine gamma-ray detection medium, thereby solving the peak position drift problem detected by the probe to a great extent.

The technical scheme of the utility model is further described in detail through the drawings and the embodiments.

Drawings

FIG. 1 is a perspective view of a radioactive gaseous iodine monitoring device provided by the utility model;

fig. 2 is a schematic diagram of a probe structure of a radioactive gaseous iodine monitoring device provided by the utility model.

Reference numerals illustrate:

a 1-L-shaped plate; 2-a vent pipe; 3-a first shut-off valve;

4-a filter; 5-monitoring; 6-flushing pipe;

7-a flow meter; 8-a flow regulating valve; 9-an air pump;

10-an electrical box; 11-a display device; 12-a second shut-off valve;

501-iodine box; 502-a probe; 503-multichannel analyzer;

5021-MgO reflective layer; 5022-scintillator; 5023-optocoupler silicone oil;

5024-photomultiplier tubes; 5025-preamplifiers; 5026-signal output connection;

5027-probe housing.

Detailed Description

As shown in fig. 1 and 2, the present utility model provides a radioactive gaseous iodine monitoring device, which is provided with a ventilation pipe 2, wherein the ventilation pipe 2 is sequentially communicated with a monitor 5, a flowmeter 7 and an air pump 9, the monitor 5 is electrically connected with a display device 11, and the flowmeter 7, the air pump 9 and the display device 11 are electrically connected with an electrical box 10, and the radioactive gaseous iodine monitoring device is characterized in that the monitor comprises: an iodine box 501 communicating with the ventilation pipe 2; the probe 502 is arranged at the top of the iodine box 501, a lanthanum bromide scintillator is used as a detection medium of radioactive iodine gamma rays in the probe, and a lanthanum isotope La-133 in the lanthanum bromide scintillator is used as a peak stabilizing source for calibrating the peak position detected by the probe; a multi-channel spectrum analyzer 503, which is disposed on the top of the probe and electrically connected to the display device.

In this embodiment, after the radioactive gaseous iodine passes through the inlet of the breather pipe 2, the radioactive gaseous iodine sequentially flows through the monitor 5, the flowmeter 7, the air pump 9 and finally flows out of the outlet of the breather pipe to the place exhaust pipe, the monitor 5 is electrically connected with the display device 11, and the flowmeter 7, the air pump 9 and the display device 11 are electrically connected with the electric box 10.

Specifically, the monitor 5 includes: an iodine box 501, a probe 502 and a multi-channel energy spectrum analyzer 503. The probe 502 is arranged above the iodine box 501, and the probe 502 uses a lanthanum bromide scintillator with gamma radioactivity as a radioactive iodine gamma-ray detection medium, so that the peak position drift problem detected by the probe can be solved to a great extent; the lanthanum isotope La-133 of the lanthanum bromide scintillator can emit gamma rays with the energy of 1468KeV, the peak position of the gamma rays 364KeV of iodine is calibrated or stabilized and the region of interest is measured by using the gamma rays with the energy as reference energy, the influence caused by the drift of the peak position detected by a probe can be eliminated, and the equipment has better use performance; measuring the region of interest more accurately, which results in a more stable and accurate measurement result; the lanthanum isotope La-133 of the lanthanum bromide scintillator is used as a peak stabilizing source, so that the use of an embedded peak stabilizing source is avoided, and the performance advantage is achieved; the probe does not contain an embedded source, so that qualification requirements of production and use units of the iodine continuous monitor equipment are reduced; after the equipment is retired, as the probe does not contain a source, the probe does not need special treatment; the lanthanum bromide scintillator is used as a radioactive iodine gamma-ray detection medium, so that the influence of temperature on measurement is avoided or reduced, the equipment can work at a wider environment temperature, and the equipment has better temperature adaptability; the iodine box 501 is an active carbon component iodine box, has higher adsorption efficiency, can adsorb atomic iodine, is communicated with the breather pipe 2, and is provided with a lead box 504 outside the iodine box 501 and the probe 502; the concentration activity of iodine can be measured by arranging the multi-channel energy spectrum analyzer 503, the model of the multi-channel energy spectrum analyzer 503 is NPT-750-ZX1, and the multi-channel energy spectrum analyzer 503 is directly used in the prior art and is not described herein.

Specifically, the flow meter 7 is a mass flow meter, and obtains flow parameters during operation of the device, and after the collected flow parameters are sent to the electrical box 10, the electrical box 10 forwards the flow parameters to the display device 11 for display.

Specifically, the air pump 9 is electrically connected to the electric box 10 for controlling the flow of the gas.

Specifically, the electrical box 10 is mainly responsible for power supply access, power supply switching, power supply and manual control of the equipment, the flowmeter, the display device and the air pump.

More specifically, the probe includes: mgO reflective layer 5021, lanthanum bromide scintillator 5022, photo coupler silicone oil 5023, photomultiplier tube 5024, preamplifier 5025, multichannel signal output connector 5026, and probe housing 5027. The reflecting layer 5021 is used for reflecting gamma rays and photons generated by the lanthanum bromide scintillator 5022, magnesium oxide is generally used, silicone oil is used for filling gaps between the lanthanum bromide scintillator and the photomultiplier tube, the optical conductivity is improved, the photomultiplier tube 5024 is used for converting light generated by the lanthanum bromide scintillator 5022 into electric signals, and the preamplifier 5025 is used for amplifying the electric signals with weak front ends so as to be beneficial to transmission and subsequent processing.

It should be noted that the method further comprises:

a filter 4 is provided on the ventilation pipe 2 and is located between the air inlet and the iodine box 501.

In this embodiment, the filter 4 is mainly used for filtering out dust particles and aerosols with smaller particle sizes, so that the apparatus can be suitable for trace dust-containing air, and the service life of the iodine box is prolonged.

It should be noted that the method further comprises:

a first shut-off valve 3 is provided on the ventilation pipe 2 and is located between the air inlet and the filter 4.

In this embodiment, the first shut-off valve 3 is used to control the inflow of radioactive gaseous iodine and to prevent the communication of the pipes before and after the first shut-off valve 3.

It should be noted that the method further comprises:

a purge pipe 6 provided on the breather pipe 2 and located between the intake port and the first shut-off valve 3.

In this embodiment, the purge port is connected to high-pressure air, so as to purge the pipeline in front of the first stop valve 6 of the device, remove the dust deposited in the pipeline, and avoid the problem that the flow is affected by increasing the pipeline resistance due to the deposition of the dust or the valve and the filter 4 are blocked by the dust plaque which is accidentally dropped.

It should be noted that the method further comprises:

a flow regulating valve 8 provided on the breather pipe 2 and located between the air pump 9 and the flow meter 7.

In this embodiment, a flow rate regulating valve 8 is located behind the flow meter 7 for regulating the flow rate to be within a proper range.

It should be noted that the method further comprises:

a second stop valve 12 is provided on the vent pipe 2 and is located between the air outlet and the flow regulating valve 8.

In this embodiment, the second stop valve 12 is located at the end of the vent pipe 2, and closing this valve can isolate the equipment air path from the site vent pipe.

It should be noted that the method further comprises:

the fixing frame is used for fixing the vent pipe 2, the purge pipe 6, the monitor 5, the flowmeter 7, the air pump 9, the electric box 10 and the display device 11.

In this embodiment, the fixing frame is an L-shaped plate 1, the vent pipe 2, the purge pipe 6, the flowmeter 7 and the display device 11 are fixed on the vertical plate of the L-shaped plate 1, and the air pump 9, the monitor 5 and the electric box 10 are fixed on the horizontal plate of the L-shaped plate.

The foregoing description is only a preferred embodiment of the present utility model, and is not intended to limit the present utility model, and any simple modification, variation and equivalent structural changes made to the above embodiment according to the technical substance of the present utility model still fall within the scope of the technical solution of the present utility model.

Claims (7)

1. The utility model provides a radioactive gaseous iodine monitoring devices, its includes the breather pipe, be equipped with monitor, flowmeter, air pump on the breather pipe in series in proper order, the monitor is connected with the display device electricity, flowmeter, air pump and display device are connected with the electric box electricity, its characterized in that, the monitor includes:

an iodine box in communication with the vent tube;

the probe is arranged at the top of the iodine box, a lanthanum bromide scintillator is used as a detection medium of radioactive iodine gamma rays in the probe, and a lanthanum isotope La-133 in the lanthanum bromide scintillator is used as a peak stabilizing source for calibrating the peak position detected by the probe;

the multichannel energy spectrum analyzer is arranged at the top of the probe and is electrically connected with the display device.

2. A radioactive gaseous iodine monitoring apparatus according to claim 1, further comprising:

the filter is arranged on the breather pipe and is positioned between the air inlet of the breather pipe and the iodine box.

3. A radioactive gaseous iodine monitoring apparatus according to claim 2, further comprising:

and the first stop valve is arranged on the vent pipe and is positioned between the air inlet of the vent pipe and the filter.

4. A radioactive gaseous iodine monitoring apparatus according to claim 3, further comprising:

and one end of the purging pipe is connected with the vent pipe between the air inlet of the vent pipe and the first stop valve.

5. The radioactive gaseous iodine monitoring apparatus according to claim 4, further comprising:

and the flow regulating valve is arranged on the vent pipe and is positioned between the air pump and the flowmeter.

6. The radioactive gaseous iodine monitoring apparatus according to claim 5, further comprising:

the second stop valve is arranged on the vent pipe and is positioned between the air outlet of the vent pipe and the flow regulating valve.

7. The radioactive gaseous iodine monitoring apparatus according to claim 6, further comprising:

the fixing frame is used for fixing the vent pipe, the purging pipe, the monitor, the flowmeter, the air pump, the electric box and the display device.

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