CN210604996U

CN210604996U - Detector assembly for continuously discriminating activity of radioactive contamination material

Info

Publication number: CN210604996U
Application number: CN201920908409.1U
Authority: CN
Inventors: 何铮; 陈钢; 朱双华; 张永旺
Original assignee: Bosi Innor Technology Beijing Co ltd
Current assignee: Bosi Innor Technology Beijing Co ltd
Priority date: 2019-06-17
Filing date: 2019-06-17
Publication date: 2020-05-22
Anticipated expiration: 2029-06-17

Abstract

The application discloses a detector assembly for continuously discriminating activity of radioactive contamination materials, and relates to the field of radiation detection. The detector assembly is disposed at a first conveyor and a second conveyor, with an inlet hopper disposed above the first conveyor. The detector assembly includes first to third detectors. The first detector and the second detector are correspondingly arranged on two sides of the inlet hopper. The first detector is used to measure the activity of the radioactivity upstream of the inlet hopper. The second detector is used for measuring the activity of the material to be sorted and measuring the total count rate of all radioactivity. A third detector is arranged above a local area of the second conveyor for measuring the activity of the material to be sorted. The utility model provides an utilize first and second detector to realize quick measurement, utilize the third detector to select the region of interest, realize the discernment and the analysis of specific radionuclide and can effectively reduce the detection lower limit, raise the efficiency to realize high-efficient, continuous, discriminate reliably.

Description

Detector assembly for continuously discriminating activity of radioactive contamination material

Technical Field

The application relates to the field of radiation detection, in particular to a detector assembly for continuously discriminating the activity of radioactive contamination materials.

Background

Radioactive surface activity measurements are not only commonly encountered in the fields of nuclear science, radiation protection, and the like. But also in research and application in the fields of industry, agriculture, biology, medicine, environmental science, etc. The activity measurement is the determination of the amount of radionuclide contained in the substance.

The solid material to be sorted is contaminated with artificial or natural radionuclides. The contaminated solid material, which may or may not be homogeneous in physical and radioactive properties, is typically mixed with other uncontaminated solid materials of various types, such as soil, rocks, gravel, sand, concrete, crushed metal or small volume fractions, and the like. Due to the mixed existence of the 'non-pollution' and radioactive element polluted solid materials, the discrimination efficiency of the radioactive materials is not high, and the reduction of the volume of the polluted mixed materials is not easy to realize, so that the purposes of reducing the transportation and disposal costs of the polluted materials are achieved. The prior internationally leading soil sorting equipment adopts two plastic scintillation detectors to screen and sort the soil polluted by radioactivity, has higher measurement efficiency, but cannot carry out in-situ identification on nuclides in the soil and screen the soil polluted by natural nuclides and interfering nuclides, so that the equipment is not good enough in the aspects of accuracy and reliability. Therefore, how to automatically, efficiently, continuously and reliably screen and sort radioactive contamination solid materials existing in large quantities in situ is a technical problem to be solved urgently.

SUMMERY OF THE UTILITY MODEL

It is an object of the present application to overcome the above problems or to at least partially solve or mitigate the above problems.

The application provides a detector assembly for radioactive contamination material activity is screened in succession sets up in conveyer department for the continuous screening of radioactive contamination material activity, conveyer includes first conveyer and second conveyer, and they just set gradually along radioactive contamination material direction of delivery, all are used for carrying and wait to sort the material, the entry hopper has been arranged to the top of first conveyer local area for through waiting to sort the material, detector assembly includes:

the device comprises a first detector, a second detector, a third detector, a fourth detector, a fifth detector and a sixth detector, wherein the first detector and the second detector are correspondingly arranged on two sides of the inlet hopper, the first detector is used for measuring the activity of the radioactivity positioned at the upstream of the inlet hopper and is used for measuring the residual activity of conveyer belts without materials to be sorted, the conveyer belts are different in cosmic radiation and terrestrial radiation, the second detector is used for measuring the activity of the materials to be sorted and is used for measuring the total counting rate of all radioactivity, and the third detector is arranged at a conveying device behind the second sensor and before the recovery sorting device and is used for identifying the types of radioactive elements contained in the materials to be sorted and measuring the activity.

Optionally, the detector assembly discriminates and sorts continuous material flows by using a continuous difference method, the measurement value of the first detector is deducted from the total count or specific activity of the second detector by measuring the first to third detectors, the count rate or specific activity of the interfering radioactive element given by the third detector is deducted to obtain the net count or specific activity of the radioactive specific nuclide in the contaminated material, and threshold discrimination is performed to realize a solid material processing speed of 10 to 150 tons/hour, wherein the lower detection limit can reach 0.05 Bq/g.

Optionally, all inactive surfaces in each detector are provided with a shield guard for attenuating ambient background noise, the detector assembly further comprising a radiation shielding baffle correspondingly disposed below the conveyor to which each detector corresponds, the radiation shielding baffle being parallel to the corresponding conveyor, the radiation shielding baffle for attenuating the earth background noise.

Optionally, the first detector and the second detector are both gamma radiation detectors, and the third detector is a gamma spectrum detector.

Optionally, the first and second detectors are mounted at the same distance from both sides of the inlet hopper and at the same height from the first conveyor. Optionally, the third detector is arranged above a local area of the second conveyor.

Optionally, the third detector is arranged at the first conveyor after the second sensor.

Optionally, the third detector is a gamma spectrum detector, and the gamma radiation energy interval is from 50KeV to several 3MeV of radioactive elements, so that the detection interval is wide, and the third detector is configured to have an adjustable support structure to avoid counting saturation, and has a low detection lower limit.

Optionally, the detector assembly is applied to equipment for continuously screening and automatically sorting radioactive contamination material activity, and the equipment comprises an industrial personal computer which is configured to automatically identify the second detector and the first detector after replacement.

Optionally, both the second detector and the first detector may be configured as detectors with low sensitivity to gamma radiation, so as to obtain a higher measurement range, so as to achieve measurement of gamma in a natural background noise environment of up to 1 mSv/h.

The detector assembly for continuously discriminating the activity of the radioactive contamination material utilizes the advantages of high detection efficiency of the two counters in the first detector and the second detector to realize rapid measurement. The accuracy of the third detector, namely the spectrum detector, is utilized to select a region of interest (ROI), so that the identification and analysis of specific radioactive nuclides are realized, the detection lower limit can be effectively reduced, and the efficiency is improved. This application realizes carrying out automation, quick measurement to a large amount of polluting materials through the detector subassembly to realize high-efficient, continuous, reliably discriminating. And further, the continuous screening and automatic sorting equipment with the detector assembly can automatically, efficiently, continuously and reliably screen and sort in situ.

The above and other objects, advantages and features of the present application will become more apparent to those skilled in the art from the following detailed description of specific embodiments thereof, taken in conjunction with the accompanying drawings.

Drawings

Some specific embodiments of the present application will be described in detail hereinafter by way of illustration and not limitation with reference to the accompanying drawings. The same reference numbers in the drawings identify the same or similar elements or components. Those skilled in the art will appreciate that the drawings are not necessarily drawn to scale. In the drawings:

FIG. 1 is a schematic top view of an apparatus for continuous activity screening automated sorting of radioactive contamination materials according to one embodiment of the present application;

FIG. 2 is a schematic side view of the apparatus for continuous activity-discriminating automatic sorting of the radioactive contamination material shown in FIG. 1;

fig. 3 is a schematic control schematic diagram of the apparatus for continuously discriminating the activity of the radioactive contamination material for automatic sorting.

The symbols in the drawings represent the following meanings:

100 the automatic sorting equipment for continuously screening the activity of the radioactive contamination material,

a is an inlet hopper, and the inlet hopper,

b a first transporting device, B1 a second transporting device, B1X a third transporting device, B11 a first third transporting device, B12 a second third transporting device, B13 a third transporting device,

b2 recovering the sorting device and,

a first detector, a second detector, an E third detector,

1 shield guard, 2 radiation shield baffle, 3 fixed angle,

10 industrial personal computer.

Detailed Description

Fig. 1 is a schematic top view of an apparatus for continuous activity screening automated sorting of radioactive contamination materials according to one embodiment of the present application. Fig. 2 is a schematic side view of the apparatus for continuous activity screening and automatic sorting of radioactive contamination materials shown in fig. 1. Fig. 3 is a schematic control schematic diagram of the apparatus for continuously discriminating the activity of the radioactive contamination material for automatic sorting.

Referring also to fig. 2-3, as shown in fig. 1, the present embodiment provides an apparatus 100 for continuously screening and automatically sorting radioactive contamination materials, comprising: a first conveyor B, a second conveyor B1, a third conveyor B1X, an inlet hopper a, a detector assembly, a recovery and sorting device B2, and an industrial personal computer 10. The detector assembly includes a first detector D, a second detector C, and a third detector E. The first conveyor B, the second conveyor B1, and the third conveyor B1X are disposed in this order along the direction of conveyance of the radioactive contamination material. The first conveying device B and the second conveying device B1 are used for conveying materials to be sorted so as to realize continuous screening of the activity of the materials to be sorted. The third conveyor B1X is used to convey the sorted material. An inlet hopper a is arranged above a partial area of the first conveyor B for passing the material to be sorted. The first detector D and the second detector C are correspondingly arranged on two sides of the inlet hopper A. The first detector D is intended to measure the activity of radioactivity upstream of the inlet hopper a, for measuring the residual activity of different cosmic, earth and conveyor belts free of material to be sorted. The residual activity of the conveyor belt without the material to be sorted is referred to herein as the residual activity of the "clean" conveyor belt. The first detector instrument is referred to as a "guard detector". The second detector C is used to measure the activity of the material to be sorted, and its physical characteristics are the same as those of the "guard detector", i.e. the first detector D, and is used to measure the total count rate of all radioactivity. Said third detector E is arranged at the conveyor after said second sensor C and before the recovery sorting device B2 for identifying the radioactive element species contained in the material to be sorted and measuring the activity thereof. The third detector E may be arranged above a local area of the second conveyor B1. The third detector E may also be arranged at the first conveyor B after the second sensor C. A recovery sorting device B2 is arranged at the end of the second conveyor B1 for receiving the material to be sorted and outputting the sorted material. The industrial personal computer 10 is configured to receive signals from the first detector D to the third detector E, and control the recycling and sorting device B2 to sort materials and selectively output the materials to the third conveyor B1X according to the received detector signals, the configuration of each transmission device and the preset radioactive material threshold. The industrial personal computer 10 is configured to preset two radioactivity thresholds to discriminate three materials with different radioactivity, and the number of the third transfer devices B1X is three, namely, the first third transfer device B11, the second third transfer device B12 and the third transfer device B13, so as to output three materials with different radioactivity correspondingly.

Experiments prove that the solid material processing speed of 10-150 tons/hour can be achieved.

The solid material to be sorted is contaminated with artificial or natural radionuclides. The contaminated solid material, which may or may not be homogeneous in physical and radioactive properties, is typically mixed with other uncontaminated solid materials of various types, such as soil, rocks, gravel, sand, concrete, crushed metal or small volume fractions, and the like.

The apparatus 100 of the present application is applicable to the treatment of any organic or inorganic material that can be transported by any conveyor, the physical characteristics of which allow the formation of a continuous stream through an intermediary called "conveyor". The heterogeneity of radioactivity is caused by the presence of materials containing artificial and/or natural radioactive elements mixed with materials called "non-radioactive". The process allows the sorting of non-contaminating materials due to their lack of radioactive elements or their associated low specific activity.

The equipment 100 for continuously screening the radioactive contamination material activity and automatically sorting the radioactive contamination material activity utilizes the advantage of high detection efficiency of the two counters in the first detector D and the second detector C to realize rapid measurement. And selecting a region of interest (ROI) by utilizing the accuracy of the third detector E, namely the spectrum detector, so as to realize the identification and analysis of the specific radionuclide. Therefore, the solid material containing the radionuclide is rapidly and continuously screened by using the first detector D, the second detector C and the third detector E. The industrial personal computer 10 is configured to preset two radioactivity threshold values, can discriminate three materials with different radioactivity, and outputs the three materials with different radioactivity from the corresponding third conveying devices B1X through the recovery sorting device B2. The method and the device can realize continuous discrimination of the radioactivity of the solid materials polluted by radioactive elements, and continuously and automatically sort the polluted materials according to the predefined sorting criterion value. Therefore, the lower detection limit can be effectively reduced, the efficiency is improved, and the rapid measurement and sorting of a large amount of pollution materials are realized. Therefore, the technical problem that 'the radioactive contamination solid materials existing in large batch are automatically, efficiently, continuously and reliably screened and sorted in situ' in the prior art is solved.

More specifically, in this embodiment, the industrial personal computer 10 is configured to perform screening and sorting on continuous material flows by using a continuous difference method, and through measurement of the first detector D, the second detector C and the third detector E, the measured value of the first detector D is subtracted from the total count or specific activity of the second detector C, and then the count rate or specific activity of the interfering radioactive element given by the third detector E is subtracted, so as to obtain the net count or specific activity of the radioactive specific nuclide in the contaminated material, and the value is compared with a preset radioactive material threshold value to perform threshold value discrimination, so as to perform screening and sorting on the material to be sorted, so as to achieve a solid material processing speed of 10 tons to 150 tons per hour, and a detection lower limit can reach 0.05 Bq/g.

More specifically, in the present embodiment, as shown in fig. 2, all inactive surfaces in each detector, i.e., the first detector D, the second detector C, and the third detector E, are equipped with a shielding guard 1 for attenuating ambient background noise. The apparatus 100 further comprises a radiation shielding baffle 2, the radiation shielding baffle 2 is correspondingly arranged below the corresponding conveying device of each detector, the radiation shielding baffle 2 is parallel to the corresponding conveying device, and the radiation shielding baffle 2 is used for attenuating the ground background noise.

Preferably, as shown in fig. 2, the first detector D and the second detector C are both high-throughput detectors, which are both equipped with high-speed electronics, and preferably, the first detector D and the second detector C are both gamma radiation detectors. The first detector D and the second detector C are radiation shielded on what is called "inactive" surfaces, i.e. the first detector D and the second detector C are equipped with shield shields 1 on all "inactive" surfaces. Shield guard 1 may attenuate environmental background noise that may be caused by cosmic radiation, material to be sorted present in or near the process line. Two radiation shielding baffles 2 are located below the first conveyor B and correspond to the first detector D and the second detector C to attenuate the earth background noise. And calculating and confirming the thickness of the shielding baffle according to the optimal attenuation coefficient of the main radionuclide. For higher levels of environmental radioactivity or the presence of more active contaminating materials or large radiation effects, the thickness of the shielding baffles can be easily adjusted to compensate for the additional thickness.

Only the "active" surfaces of the first detector D and the second detector C are not shielded, otherwise the radiation present in the material being measured cannot be detected. The shielding shutter is located below the first conveyor B and corresponds to the positions of the first detector D and the second detector C. These shielding baffles have a size large enough for effective attenuation of the earth radiation and form a closed fixed detection angle with the corresponding first and second detectors D, C.

The first detector D and the second detector C are identical in characteristics. The first detector D and the second detector C are distributed on two sides of the inlet hopper A and are arranged at the same distance from the two sides of the inlet hopper A. The arrangement in which the first detector D and the second detector C are mounted at the same height from the first conveyor B, i.e. they have the same height with respect to the first conveyor B, facilitates the first detector D and the second detector C receiving the same interference radiation, i.e. radiation from the material in the inlet hopper a, geodetic radiation and cosmic radiation. The configuration and physical characteristics of the collimation and attenuation shields of the first and second detectors D, C are also identical. By using this method, in the operating mode, the measured value of the second detector C can be directly subtracted from the measured value of the "guard detector", i.e. the first detector D, thereby avoiding introducing any correction factor that may cause errors. During the start-up phase of the apparatus 100, this method simplifies the calibration procedure for normal operation of the detector, and only requires comparing the values of the first detector D and the second detector C. The values of the first detector D and the second detector C should be identical or close in statistical counting error. If the variance of the measurements from the first detector D and the second detector C exceeds the adjustable range of uncertainty, this indicates the presence of a radioactive source in the vicinity of the first conveyor B and/or the detector with the higher reading value. In this case, corrective action is taken to return the apparatus 100 to the normal operating mode.

Furthermore, the electronic components of the first detector D and the second detector C can make the counting capacity more than 10 times of that of the conventional electronic components.

In other embodiments, where materials of high radioactivity levels are sorted, the apparatus 100 requires modularity and high durability. The first detector D and the second detector C may be replaced by detector modules that are not sensitive to gamma radiation, but have a very high counting capacity and a wider measurement range. For example, the first detector D and the second detector C may be conveniently replaced by less sensitive gamma detectors to obtain a higher count range for sorting higher radioactive materials. So that the first detector D and the second detector C can measure gamma in a natural background noise environment of up to 1 mSv/h. This modular functionality allows the device 100 to be quickly started and operated regardless of the type of material and activity.

The device 100 of the present application is designed with the interchangeable function of the probe in mind: from a physical point of view, an upgrade space is reserved at the positions of the existing first detector D and the second detector C. From the software perspective, the human-machine interface can quickly identify the new detector after the new detector is connected, and automatically provide the new proper detection criterion value for the operator.

Based on this, the first detector D and the second detector C of the present application may employ a modular design. The modularization enables the replacement of the detectors to be completed within 2 hours, and the modules of the first detector D and the second detector C are skillfully placed on the sliding rails and fixed on the rubber protective layer through screws so as to avoid the influence of any harmful vibration on the operation of the instrument. The assembly mode can avoid accidental alarm and effectively prolong the service life of the detector.

More specifically, the industrial personal computer 10 is configured such that the second detector C and the first detector D replace the automatic identification function, and after the new second detector C and the new first detector D are connected to the device 100, the software of the industrial personal computer 10 can quickly and automatically identify the new second detector C and the new first detector D.

In this embodiment, as shown in fig. 2, the third detector E preferably employs a gamma spectrum detector. The radioactive elements with gamma radiation energy interval from 50KeV to several 3MeV are detected, the detection interval range is wide, the supporting structure is adjustable, the counting saturation can be avoided, and the lower detection limit can reach 0.05 Bq/g.

Description of the structure of the third detector E: in general, radioactive element contaminated materials are difficult to quickly and efficiently screen and sort, which requires the use of large-area, high-sensitivity gamma detectors and has an excellent lower limit for the detection of artificial radionuclides; it is also desirable to have a gamma spectrum detector suitable for radioelement identification and a longer measurement time. This application combines above-mentioned two kinds of modes, through using first detector D and second detector C, introduces the third detector E simultaneously, and it is the bulky detector that is used for discerning the radioactive element to ensure radioactive contamination material and examine the accuracy and the high efficiency of sorting. In order to maintain high efficiency, a gamma spectrum detector using a sodium iodide crystal is preferably used in the present embodiment. Of course, such crystals may be replaced by any other type of crystal having radioactive element recognition capability. The third detector E is provided with electronic components, so that the counting capacity can reach more than 10 times that of the conventional electronic components.

The third detector E and the gamma spectrum detector are used to count a complete absorption peak (characteristic of a radionuclide) over a sufficiently long period of time (T), such as during the lifting of the material on the second conveyor B1, in order to analyze its activity. This number is divided by the time (T) and the mass of the material within the coverage of the fixed angle 3 of the third detector E, the gamma-spectral detector, the value thus obtained represents the specific activity of the (interfering) radionuclide (including the natural radioactive elements) analyzed by means of a corresponding data table stored in the hard disk of the industrial control computer 10 to which the human-computer interface is connected. This specific activity value will be subtracted from the value of the second detector C.

All inactive surfaces of the third detector E, the gamma spectrum detector, are provided with shield guards 1 and are adjustable in position to control the collimation angle and distance of the detectors relative to the second conveyor B1. The positioning is based on the optimal distance and collimation angle to ensure that it provides the most appropriate detection limit without saturating the count. This function may allow a greater range of settings to enable it to detect radionuclides with gamma radiation energies in the range of tens of KeV to several MeV. In addition, a radiation shielding baffle 2 corresponding to the third detector gas is located below and parallel to the second conveyor B1, perpendicular to the sensitive "active" surface of the third detector E.

Description of measurement mode of the third detector E: the third detector E delivers information in the form of an energy spectrum, each energy spectrum line or identified peak in the energy spectrum corresponding to a characteristic of a radionuclide. The net integral measured under each peak represents the radioactivity characteristic of a particular nuclide.

The third detector E has a fixed position and geometry in the apparatus 100 and therefore allows the transfer function to be used and corrected by the actual volume of material covered by the third detector E at a fixed angle 3. The specific activity of a particular radionuclide (including naturally occurring radioactive elements) in the material is thus obtained.

By gamma spectrometry, specific radionuclides (including naturally occurring radioactive elements) can be known and quantified. In addition, the first detector D and the second detector C, i.e., the detectors sensitive to two gamma radiations, are subjected to counting simulation, and a correction factor (efficiency factor) K of a specific radionuclide (including a natural radioactive element) is determined, recorded as a table, and stored in the industrial personal computer 10.

For the identified interfering natural nuclides and/or artificial nuclides, the software of the industrial personal computer 10 will automatically obtain the corresponding correction factor K and operate it with the measured value of the third detector E. The sum of the calculated value and the value of the background noise given by the first detector D will be subtracted from the measured value of the second detector C.

By the method and the device, the sorting equipment 100 can be guaranteed to have very low detection lower limit and sorting threshold, and the net counting rate and the actual specific activity of the radioactive nuclide of interest can be rapidly obtained within a very short measuring time.

In this embodiment, as shown in fig. 2, the first conveyor B, the second conveyor B1 and the third conveyor B1X are all conveyor belts. More specifically, in the present embodiment, the first conveying device B is a horizontal conveying belt. In view of the compactness and modularization of the whole apparatus 100, the second conveyor B1 and the third conveyor B1X are climbing conveyors inclined upward relative to the horizontal plane, and the second conveyor B1 and the first conveyor B and the third conveyor B1X are stacked on each other in position, so that the height of the whole apparatus 100 is increased by the inclined angle, and the total length of the apparatus 100 is reduced. This angle of inclination lifts and dumps the material on the second conveyor B1 into the volume of the recovery sizer B2, which then guides the material again by the second conveyor B1 to the different post-sizer outputs, namely the first third conveyor B11, the second third conveyor B12 and the third conveyor B13.

The first conveying device B can adjust the material conveying speed by selecting the speed of the motor, meanwhile, the thickness of the material above the first conveying device B can also be continuously adjusted, the set height depends on the physical state of the material and the source item of the material, and the two parameters can be controlled by the industrial personal computer 10 and can also be manually configured by a process line operator.

In this embodiment, the apparatus 100 has three exit output transfer modes with dual discrimination thresholds. The third conveyor B1X is in particular a first third conveyor B11, a second third conveyor B12 and a third conveyor B13, all of which are three climbing belts that output the material in particular according to the definition of the activity threshold.

In other embodiments, the apparatus 100 can also be a dual output sort output transfer mode with a single fixed discrimination threshold. Only two positions of the third conveyor B1X need to be maintained, for example the third conveyor B1X, in particular the first third conveyor B11 and the second third conveyor B12, i.e. the two climbing conveyors, in particular to deliver the material according to the definition of the activity threshold.

As shown in fig. 3, the material receiving recovery sorting apparatus B2 of the present application may be controlled by the industrial personal computer 10 to direct material to two or three locations. The recycling and sorting device B2 is a conventional device, for example, the recycling and sorting device B2 is a swingable hopper, and the structure of the recycling and sorting device B2 is not described in detail in this embodiment.

The material to be measured, sorted is measured for all total radioactive count rates (CPSGross) at the second detector C, and the values of the specific radionuclides (including natural radioactive elements) analyzed, deduced back (after CPS E) by subtracting all Background rates (CPS Background) given by the first detector D and the third detector E) of the environmental Background rates (CPS Background) given by the first detector D, the resulting continuous differential net count rates or specific activities are compared with the values of the defined sorting criteria or activity thresholds set in the human-machine interface, in order to trigger the directional positioning of the recovery sorter B2 towards one of the final three conveyors, namely the first third conveyor B11, the second third conveyor B12 and the third conveyor B13. Only the lower portion of the recovery sorter B2 is motorized to reduce response time while reducing motion inertia for optimal high frequency, high efficiency sorting performance. The speed and position of all the conveyor belts are known at all times, which allows the motorized portion below the reclaim sorter B2 to be easily controlled to ensure that the measured, screened material is directed onto the correct output conveyor.

By selecting one or two sorting criterion values or activity thresholds, respectively, the guiding devices in the recovery sorting device B2 can be correspondingly effectively adapted to two or three secondary climbing conveyors, namely the first third conveyor B11, the second third conveyor B12 and the third conveyor B13.

More specifically, in this embodiment, the inlet hopper a is configured such that the material is fed by gravity alone. The inlet hopper a transfers the material in the inlet hopper a to the first conveyor B without mechanical intervention. In particular, the inlet hopper a is typically a volume in the form of a funnel bin. The geometry of the volume is such that the material can be fed by gravity alone without mechanical intervention. After the material has reached the first conveyor B, the material flow can be adjusted by:

the vertical position of the metal baffle can be adjusted through a human-computer interface or manually so as to control the thickness and the volume of the material passing under the second detector C. Or

The speed of movement of the first conveyor B is adjusted by means of a human-machine interface, so as to control the speed of passage of the material flow under the probe.

In particular, the inlet hopper a may be fed by an excavator or any known material transfer means. Above the inlet hopper a there is provided a device with screening function and configured for gravity screening or vibratory screening of the material to be sorted for size screening. The device may size the feed material by gravity or vibration.

More specifically, the apparatus 100 of the present application may be integrated into a 40 foot international standard container. The regulator cubicle passes through the single power interface power supply of 400 volts, and field operation is simple need not electrician's personnel and intervenes. All functions of the apparatus 100 are automatically coordinated with each other after start-up. Device 100 may be powered using a regional power source or by a generator set with stable output. The device 100 may have a human-machine interface that can be remotely controlled and set up, which makes control and operation maintenance work easier without requiring experienced technicians to stay on site for extended periods of time. Specifically, the industrial personal computer 10 and the human-machine interface HMI can be used for local operation or remote control to collect all data of different detectors, motors and radioactive detectors.

According to the diffusion requirement, the sealing grade of the container can be improved or a ventilator set can be assembled, so that the diffusion of the radioactive substances can be controlled. The third conveyor B1X, the sort output conveyor, may be integrated into a soft or rigid dust cover and connected to a trash can or bag. The environment of the entire apparatus 100 is set to a negative pressure state.

Referring to fig. 2, the present application further provides a detection method for continuously screening and automatically sorting the activity of radioactive contamination materials by using the apparatus 100, which is operated according to the following steps:

step 101, in the starting stage of the equipment 100, comparing the numerical values of the first detector D and the second detector C, and if the numerical values of the first detector D and the second detector C are completely the same or the counting statistical errors are similar, the detectors normally operate; if the variance of the measured values exceeds the uncertainty adjustable range, it is checked whether a radioactive source is present in the vicinity of the first conveyor B and/or the detector with the higher reading value and excluded to restore the normal operation of the apparatus 100.

At step 102, radioactive contaminated solid materials to be sorted, (e.g., contaminated soil and mixed materials) are loaded into an inlet hopper A through an excavator or conveyor, through a screening device, and into an inlet hopper A.

In step 103, the material to be sorted is transferred from the inlet hopper a to the first conveyor belt. In the process of implementing the process, the accurate position of the first conveying device B can be determined by accurately controlling the speed of the motor and feeding back information of the detectors at different positions. The apparatus 100 can identify the position of the first conveyor B at any time to ensure that the value measured by the "guard detector", i.e. the first detector D, corresponds to the value given by the second detector C when the first conveyor B is located directly below the second detector C.

104, recording the gamma counting rate or the radioactivity ratio of the upstream of the inlet hopper A measured by the first detector D by the industrial personal computer 10; which represent the residual count rates or specific activity count rates of different cosmic, earth and so-called "clean" (no material to be sorted) conveyor belts.

105, the industrial personal computer 10 records all the total radioactive counting rates or specific activities of the materials to be sorted, which are measured by the second detector C;

106, continuously identifying radionuclides in the material flow by using the third detector E and the lifting time of the material to be sorted on the second conveying device B1, and analyzing and reversely deducing the counting rate or the radioactivity ratio of specific radionuclides (including natural radioactive elements) through the data of the third detector E and the industrial personal computer 10 for the identified interfering natural nuclides and/or artificial nuclides;

step 107, subtracting the measurement value of the first detector D from the measurement value of the second detector C, and then subtracting the count rate or radioactivity ratio of the specific (interfering) radioactive element (such as natural radioactive element) from the measurement value of the third detector E, so as to realize continuous differential count measurement, wherein the differential count result is used for the screening and sorting of the contaminated materials;

at the same time, the material to be sorted is transferred by the first conveyor B to the second conveyor B1, which second conveyor B1 carries the material to the recovery sorting device B2;

in step 108, the industrial personal computer 10 controls the recycling and sorting apparatus B2 to guide the sorted materials to the third transfer apparatus B1X, i.e., the first third transfer apparatus B11, the second third transfer apparatus B12 and the third transfer apparatus B13, according to the analysis result.

The detection method for continuously screening and automatically sorting the activity of the radioactive contamination material utilizes the advantage of high detection efficiency of the two counters in the first detector D and the second detector C to realize rapid measurement. And selecting a region of interest (ROI) by utilizing the accuracy of the third detector E, namely the spectrum detector, so as to realize the identification and analysis of the specific radionuclide. The method and the device can realize continuous discrimination of the radioactivity of the solid materials polluted by radioactive elements, and continuously and automatically sort the polluted materials according to the predefined sorting criterion value. Therefore, the lower detection limit can be effectively reduced, the efficiency is improved, and the rapid measurement and sorting of a large amount of pollution materials are realized.

It is to be noted that, unless otherwise specified, technical or scientific terms used herein shall have the ordinary meaning as understood by those skilled in the art to which this application belongs.

In the description of the present application, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present application.

Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. In the description of the present application, "a plurality" means two or more unless specifically defined otherwise.

In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

The above description is only for the preferred embodiment of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present application should be covered within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. Detector assembly for the continuous activity screening of radioactive contamination materials, characterized in that it is arranged at a conveyor for the continuous activity screening of radioactive contamination materials, said conveyor comprising a first conveyor (B) and a second conveyor (B1) which are arranged in sequence along the direction of transport of the radioactive contamination materials, both for the transport of the materials to be sorted, an inlet hopper (a) being arranged above a local area of the first conveyor (B) for the passage of the materials to be sorted, said detector assembly comprising:

-first to third detectors (D, C, E), wherein a first detector (D) for measuring the activity of radioactivity upstream of the inlet hopper (a) for measuring the residual activity of the conveyor belt of different cosmic radiation, ground radiation and no material to be sorted and a second detector (C) for measuring the activity of radioactivity of the material to be sorted for measuring the total count rate of all radioactivity are arranged on both sides of the inlet hopper (a) and a third detector (E) for identifying the type of radioactive element contained in the material to be sorted and measuring the activity thereof is arranged at the conveyor after the second detector (C) and before the recovery sorting device (B2).

2. A detector assembly according to claim 1, characterized in that all inactive surfaces in each detector are provided with a shield guard (1) for attenuating ambient background noise, the detector assembly further comprising a radiation shielding baffle (2), the radiation shielding baffle (2) being correspondingly arranged below the corresponding conveyor of each detector, the radiation shielding baffle (2) being parallel to the corresponding conveyor, the radiation shielding baffle (2) being for attenuating earth background noise.

3. The detector assembly of claim 1, wherein the first detector (D) and the second detector (C) are each gamma radiation detectors and the third detector (E) is a gamma spectrum detector.

4. The detector assembly according to claim 1, characterized in that said first detector (D) and said second detector (C) are mounted at the same distance from both sides of said inlet hopper (a) and at the same height from said first conveyor (B).

5. The detector assembly according to claim 1, characterized in that the third detector (E) is arranged above a local area of the second conveyor (B1).

6. The detector assembly according to claim 1, characterized in that the third detector (E) is arranged at the first conveyor (B) after the second detector (C).

7. The detector assembly of claim 1, wherein the third detector (E) is a gamma spectrum detector, and the gamma radiation energy range is wide by detecting radioactive elements from 50KeV to several 3MeV, and the third detector (E) is configured with an adjustable support structure to avoid saturation of counts, while having a low lower detection limit.

8. Detector assembly according to any one of claims 1 to 7, characterised by being applied to a device for the continuous screening automatic sorting of the activity of radioactive contaminated materials, comprising an industrial control computer (10), the industrial control computer (10) being configured to automatically identify the second detector (C) and the first detector (D) after replacement.

9. The detector assembly of claim 1, wherein the second detector (C) and the first detector (D) are each configured as detectors with low sensitivity to gamma radiation, thereby allowing a higher measurement range for measuring gamma in natural background noise environments of up to 1 mSv/h.