A soil radon emanation rate measuring device and a sandstone type uranium ore prospecting method

Abstract

The present application relates to radioactive gas detection and sandstone type uranium exploration technical field, especially a soil radon emission rate measuring device and its sandstone type uranium ore prospecting method, including gas collecting mechanism, including PVC gas collecting cylinder, the top of PVC gas collecting cylinder is provided with sealing cover, the top of sealing cover is provided with atmospheric temperature and humidity pressure sensor and internet of things antenna respectively, the bottom of PVC gas collecting cylinder is installed with soil temperature and humidity sensor;Detection mechanism, it is cylindrical sealing mechanism, including chip storage module, photon counter.The present application realizes the underground in-situ stable measurement of soil radon emission rate by vertically burying PVC gas collecting cylinder in a certain depth under the ground, makes radon diffuse and accumulate naturally in the relatively closed and stable space from bottom to top, avoids the sealing problem and wind field interference under the open environment condition of the ground.In addition, cooperating with internet of things remote transmission technology, long-term continuous automatic observation and unattended can be realized, which significantly improves the field exploration efficiency.

Description

Technical Field

[0001] This invention relates to the field of radioactive gas detection and sandstone-type uranium deposit exploration technology, and in particular to a soil radon release rate measuring device and its sandstone-type uranium deposit prospecting method. Background Technology

[0002] Radon release rate is a physical parameter characterizing the amount of radon released per unit time and per unit area. It is an important indicator for assessing the ability of radon to be released from the surface of radium-containing porous media such as rocks and soil into the air. From the perspective of radioactive decay mechanisms, uranium decays to produce radium, and radium further decays to produce radon gas (radon gas). 222 Radon (Rn) has a half-life of approximately 3.825 days. It is continuously produced in the uranium-radium-radon radioactive equilibrium system and migrates upwards through diffusion and convection in soil pores. As metallic uranium is an important strategic energy mineral, when uranium-rich deposits exist underground, relatively stable radon release anomaly zones often form in the overlying soil. Therefore, soil radon release rate is considered an important indirect indicator of the presence of deep uranium deposits and has significant application value in sandstone-type uranium deposit exploration.

[0003] Currently, radon emission rate measurement methods mainly fall into two categories: active measurement and passive accumulation measurement. Active measurement methods primarily include the closed-loop method and the flow-gas method, which involve covering the ground surface with a gas collection hood and extracting gas to measure changes in radon concentration to invert the emission rate. Passive methods include activated carbon accumulation and solid nuclear track detection methods. Although these methods have been applied in environmental monitoring and mineral exploration, they still have significant shortcomings: the closed-loop method, with its long-term closed operation, is prone to excessive radon accumulation, leading to leakage and back-diffusion effects, resulting in lower measurement results; the negative pressure generated during the extraction process in the flow-gas method can cause mixing with low-concentration external air, resulting in an overestimation of the emission rate; the activated carbon method and the nuclear track method have long measurement cycles, making real-time dynamic monitoring difficult, and are greatly affected by environmental conditions.

[0004] Furthermore, existing measuring devices typically employ surface gas collection hoods, which require sealing around the hood and are susceptible to interference from external environmental factors such as air pressure, temperature, humidity, and wind speed, making it difficult to stably reflect the radon release characteristics of deep geological bodies. Moreover, the exploration of deep, concealed mineral deposits is quite challenging. Therefore, this paper proposes a soil radon release rate measuring device and its application method for sandstone-type uranium deposit exploration. Summary of the Invention

[0005] In view of the problems of negative pressure during air extraction or leakage error of the gas collection hood in the above or existing technologies, and the inability to achieve real-time remote monitoring of radon exhalation rate measurement, the present invention is proposed.

[0006] Therefore, the purpose of this invention is to provide a soil radon exhalation rate measuring device.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: including, The gas collection mechanism includes a PVC gas collection cylinder, the top of which is provided with a sealing cover. An ambient temperature, humidity and pressure sensor and an Internet of Things antenna are respectively installed on the top of the sealing cover. A soil temperature and humidity sensor is installed at the bottom of the PVC gas collection cylinder. The testing mechanism is a cylindrical sealed structure, including a chip storage module, a photon counter, a ZnS(Ag) scintillation chamber, and a gas diffusion port; It also includes a battery for powering the gas collection and detection mechanisms.

[0008] As a preferred embodiment of the soil radon exhalation rate measuring device of the present invention, wherein: the PVC gas collecting cylinder is a hollow cylindrical structure; The PVC gas collecting cylinder has an external thread structure at the top, which allows for a detachable and sealed connection with the top sealing cap of the gas collecting cylinder through the threaded interface.

[0009] In a preferred embodiment of the soil radon exhalation rate measuring device of the present invention, the ambient temperature, humidity and pressure sensor, the Internet of Things antenna and the measuring mechanism are all electrically connected to the battery via cables.

[0010] As a preferred embodiment of the soil radon exhalation rate measuring device of the present invention, the PVC gas collecting cylinder is made of PVC material with a wall thickness of 5mm, and a fluororubber sealing ring is installed at the threaded connection between the PVC gas collecting cylinder and the sealing cap at the top of the gas collecting cylinder.

[0011] In a preferred embodiment of the soil radon exhalation rate measuring device of the present invention, the gas diffuser is disposed on the lower end face of the detection mechanism, and a hydrophobic filter membrane is disposed inside the gas diffuser.

[0012] In a preferred embodiment of the soil radon exhalation rate measuring device of the present invention, the ZnS(Ag) scintillation chamber is connected to the internal space of the PVC gas collecting cylinder through a gas diffusion port.

[0013] As a preferred embodiment of the soil radon exhalation rate measuring device of the present invention, wherein: the inner wall of the ZnS(Ag) scintillation chamber is uniformly sprayed with a ZnS(Ag) scintillator coating, which is used to convert α particles generated by the decay of radon and its progeny into visible light photons.

[0014] In a preferred embodiment of the soil radon exhalation rate measuring device of the present invention, the photon counter is arranged correspondingly to the ZnS(Ag) scintillation chamber, and is used to convert visible light photons into electrical pulse signals and transmit them to the chip storage module.

[0015] As a preferred embodiment of the soil radon exhalation rate measuring device of the present invention, the chip storage module is used to set measurement parameters, convert pulse signals into radon activity concentration, synchronously store measurement data and environmental parameters, in-situ invert the soil radon exhalation rate based on a preset nonlinear cumulative inversion model, and realize remote data transmission through an Internet of Things antenna.

[0016] A method for measuring soil radon exhalation rate in sandstone-type uranium deposit prospecting, characterized by comprising the following steps: S1: Collect and organize geological data of the area to be explored, combine ground geophysical data, well logging data and existing mineralization information, conduct a comprehensive evaluation of the mineralization prospect, and select sandstone-type uranium mineralization prospect areas as key target areas; S2: Within the selected target area, based on the orientation of the ore-bearing sand body and the distribution characteristics of the ore-controlling structures, measuring points are set up according to the preset spacing between measuring points and measuring lines to form a soil radon exhalation rate observation network covering the target area. S3: Drill vertical holes at each measuring point that match the outer diameter of the PVC gas collecting cylinder, and vertically and stably bury the PVC gas collecting cylinder in the borehole, ensuring that its bottom opening is in full and seamless contact with the original soil at the bottom of the hole, and that the soil temperature and humidity sensor probe is fully inserted into the soil at the bottom of the hole. Use the original soil taken out from the borehole to backfill the annular gap between the outer wall of the gas collecting cylinder and the hole wall and compact it in layers. S4: Complete the electrical connection between the radon gas measuring device and the soil temperature and humidity sensor, atmospheric temperature, humidity and pressure sensor, IoT antenna and external battery. Fix the radon gas measuring device inside the PVC gas collecting cylinder, tighten the top sealing cap of the gas collecting cylinder to form a sealed cavity. After the device is powered on, continuously measure and record the radon activity concentration according to the preset measurement parameters. S5: Complete the deployment and debugging of devices at all measuring points within the target area, and collect the time series dataset of radon activity concentration at each measuring point in real time through IoT wireless transmission, and simultaneously collect and store the atmospheric and soil temperature, humidity, and air pressure environmental parameters of the corresponding measuring points. S6: The nonlinear cumulative inversion model is used to fit and analyze the time series data of radon concentration at each measuring point, and the soil radon release rate parameters at each measuring point are obtained by inversion. The spatial distribution characteristics, anomalous amplitude and continuity of radon release rate in the target area are comprehensively analyzed to identify the abnormal area of ​​soil radon release rate, so as to realize the identification and prediction of the potential distribution range of deep concealed sandstone-type uranium ore bodies.

[0017] The beneficial effects of the soil radon exhalation rate measuring device of the present invention are as follows: By vertically burying a PVC gas collection cylinder at a certain depth below the ground surface, the present invention achieves stable in-situ underground measurement of soil radon exhalation rate, allowing radon gas to naturally diffuse and accumulate from bottom to top in a relatively closed and stable space, avoiding the sealing problems and wind interference under open surface environment conditions. Furthermore, combined with IoT remote transmission technology, it enables long-term continuous automated observation and unattended operation, significantly improving the efficiency of field exploration. This invention employs in-situ diffusion-based soil radon exhalation rate measurement, continuously monitoring the dynamic changes of radon concentration over a specific time scale. A nonlinear cumulative inversion model is used to fit and calculate the time-series data, yielding the radon exhalation rate parameter. This radon exhalation rate reflects the continuous radon input flux per unit time and unit area, providing a comprehensive characterization of the cumulative change process over a period, and is more stable and representative than instantaneous concentration values. By comparing and analyzing the radon exhalation rates at various spatial measurement points, anomalous enhancement zones can be identified more reliably, thus providing a basis for the identification and prediction of concealed sandstone-type uranium deposits. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of the soil radon exhalation rate measuring device.

[0020] Figure 2 This is a schematic diagram of the internal structure of a soil radon exhalation rate measuring device.

[0021] Figure 3 This is a time series plot of radon surface precipitation rate obtained by nonlinear fitting of radon activity concentration at measuring point H2-01 in a known sandstone-type uranium deposit.

[0022] Figure 4 This is a distribution map of radon activity concentration and radon surface precipitation rate at various measuring points along a single measuring line in a known sandstone-type uranium deposit.

[0023] In the diagram: 100, gas collection mechanism; 101, PVC gas collection cylinder; 102, sealing cover; 103, ambient temperature, humidity and pressure sensor; 104, IoT antenna; 105, soil temperature and humidity sensor; 200, detection mechanism; 201, chip storage module; 202, photon counter; 203, ZnS(Ag) scintillation chamber; 204, gas diffuser; 300, battery. Detailed Implementation

[0024] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0025] Reference Figure 1 and Figure 2This is the first embodiment of the present invention, which provides a soil radon exhalation rate measuring device, which includes a gas collection mechanism 100, a detection mechanism 200 and a storage battery 300.

[0026] Specifically, the gas collection mechanism 100 includes a PVC gas collection cylinder 101. A sealing cover 102 is provided on the top of the PVC gas collection cylinder 101. An ambient temperature, humidity and pressure sensor 103 and an Internet of Things antenna 104 are respectively provided on the top of the sealing cover 102. A soil temperature and humidity sensor 105 is installed at the bottom of the PVC gas collection cylinder 101. The detection mechanism 200 is a cylindrical sealed mechanism, including a chip storage module 201, a photon counter 202, a ZnS(Ag) scintillation chamber 203, and a gas diffusion port 204; It also includes a battery 300 for supplying power to the gas collection mechanism 100 and the detection mechanism 200.

[0027] Furthermore, the PVC gas collecting cylinder 101 is made of PVC material with a wall thickness of 5mm, and has a hollow cylindrical structure with an inner diameter of 100mm and a length of 50~150cm, which can be adjusted according to the thickness of the soil cover layer in the test area. During measurement, it is vertically buried at a depth of 30~100cm below the ground surface. Its cylinder wall has a sealed structure, and the bottom is designed to be open for direct communication with the soil below, so that the radon gas released from the soil can only enter through the bottom opening of the PVC gas collecting cylinder 101, avoiding lateral radon gas interference from the soil. A soil temperature and humidity sensor 105 is fixedly installed at the bottom of the PVC gas collecting cylinder 101, with a measurement range of -30~60℃ and 0~100%RH, and a measurement accuracy of ±0.2℃ and ±2%RH, for synchronously collecting in-situ soil temperature and volumetric moisture content at the measurement point.

[0028] Furthermore, the PVC gas collecting cylinder 101 has an external thread structure at the top, which allows for a detachable and sealed connection with the top sealing cap 102 of the gas collecting cylinder through the threaded interface. A fluororubber sealing ring is installed at the thread to isolate the interference of external atmospheric fluctuations on the interior of the cavity. The inner diameter of the PVC gas collecting cylinder 101 matches the outer diameter of the radon gas measuring device, forming a tight fit structure. The radon gas measuring device is fixed at the bottom of the gas collecting cylinder to prevent radon gas from leaking along the side wall gaps and to ensure measurement accuracy.

[0029] Furthermore, the ambient temperature, humidity, and pressure sensor 103 has a measurement range of -40~85℃, 0~100%RH, and 300~1100hPa, with a measurement accuracy of ±0.2℃, ±2%RH, and ±0.5hPa. It synchronously collects external environmental parameters, and the data is connected to the detection mechanism 200 via a cable. A 4G / NB-IoT dual-mode IoT antenna 104 is fixedly installed in the center of the sealing cover 102 and is connected to the detection mechanism 200 via a cable to achieve remote real-time data transmission. Furthermore, all openings of the top sealing cover 102 of the PVC gas collecting cylinder 101 are equipped with waterproof sealing gaskets with an IP67 protection rating to prevent rainwater and outside air from entering the cavity and ensure the stability of radon gas accumulation measurement.

[0030] Preferably, the gas diffuser 204 is located on the lower end face of the detection mechanism 200 and is a porous structure with a hydrophobic filter membrane. It is connected to the internal space of the PVC gas collection cylinder 101, so that radon gas can enter the ZnS(Ag) scintillation chamber 203 without obstruction, while blocking soil moisture. The inner wall of the ZnS(Ag) scintillation chamber 203 is uniformly coated with a ZnS(Ag) scintillator coating. Alpha particles generated from the decay of radon and its progeny interact with the scintillator, releasing visible light photons. These photons are converted into electrical pulse signals by a photon counter 202. After counting the pulses, the chip storage module 201 calculates the radon activity concentration using a calibrated scale coefficient. The measurement range is 0.2~1000000 Bq / m³. 3 This meets the requirements for measuring cumulative soil radon concentration. The chip storage module 201 uses a low-power STM32 microcontroller as the main controller and has a built-in large-capacity storage chip that can store no less than 2 years of continuous measurement data. It is used to set the measurement period of the photon counter 202 to 10 min to 2 h, the sampling time to 1 to 20 min, and the pulse resolution time to 20 ns. It synchronously stores and manages the radon concentration time series data and environmental parameters, and transmits them to the remote monitoring platform in real time through the Internet of Things antenna 104. Furthermore, the chip storage module 201 has a built-in nonlinear cumulative inversion model that can directly analyze and calculate time-series data to obtain the soil radon release rate in situ.

[0031] The construction and calculation methods of the nonlinear cumulative inversion model are as follows: Radon is collected from the surface of the test medium in a sealed container. Ideally, radon gas leakage is not considered. The change of radon concentration (C) in the container over time is as follows: (1) In the formula, E is the radon surface release rate. S is the area of ​​the gas ejection medium covered by the container; V is the volume of the container; t is the accumulation time, in seconds. The decay constant of radon is 2.1 × 10⁻⁶. -6 λ1 is the anti-diffusion coefficient, s -1 ;λ b Let s be the leakage coefficient. -1 .

[0032] When the initial condition is C| t When =0=C0, equation (1) has the following solution: (2) Transforming equation (2) yields: (3) Nonlinear fitting, the fitting equation is shown in equation (4): (4) in: (5) (6) Here, parameter E represents the radon input flux per unit area per unit time entering the gas collection space, i.e., the radon release rate; parameter b represents the comprehensive loss term, including the attenuation effect caused by radon free decay, device leakage effect, and back-diffusion factors. If the radon release rate obtained by fitting in certain areas is significantly higher than the background value, it usually indicates that there may be uranium-rich geological bodies or uranium mineralization anomalies underground. The reason is that uranium-series nuclides (mainly...) 226 Ra) continues to be generated during the decay process. 222 Ore bodies or mineralizations with high uranium (Rn) content can provide a stronger radon source term, enhancing radon recharge in the overlying soil and resulting in a higher surface radon release rate. Therefore, areas with anomalies in radon release rate can serve as indicators of concealed uranium deposits or favorable mineralization sites, providing a basis for subsequent geological verification.

[0033] Example 2, refer to Figure 1 and Figure 2 This is the second embodiment of the present invention. Unlike the previous embodiment, this embodiment provides a method for measuring soil radon exhalation rate in sandstone-type uranium deposits.

[0034] Includes the following steps: S1: Collect and organize geological data of the area to be explored, combine ground geophysical data, well logging data and existing mineralization information, conduct a comprehensive evaluation of the mineralization prospect, and select sandstone-type uranium mineralization prospect areas as key target areas; S2: Within the selected target area, based on the orientation of the ore-bearing sand body and the distribution characteristics of the ore-controlling structures, a soil radon exhalation rate measurement profile line perpendicular to the orientation of the sand body is laid out. The total length of the line is 1900m, and 20 effective measuring points are laid out along the line at a spacing of 100m to form a soil radon exhalation rate observation network covering the target area. S3: At each measuring point along the survey line, a portable soil drilling machine was used to drill vertical circular holes. The hole diameter matched the outer diameter of the PVC gas collecting cylinder 101, and the drilling depth was controlled at 60cm, consistent with the height of the PVC gas collecting cylinder 101 used in this study. The PVC gas collecting cylinder 101 was vertically and stably buried in the drilled hole, ensuring full and gapless contact between the fully open cavity at the bottom of the gas collecting cylinder and the in-situ soil at the bottom of the hole. At the same time, the soil temperature and humidity sensor 105 probe pre-installed at the bottom of the gas collecting cylinder was fully inserted into the in-situ soil at the bottom of the hole to achieve in-situ synchronous measurement of soil parameters and radon concentration and activity. Subsequently, the undisturbed soil extracted from the drilled hole was used to backfill the annular gap between the outer wall of the gas collecting cylinder and the hole wall, and the soil was compacted in layers to eliminate pore disturbance caused by drilling, prevent outside air from forming a leakage channel along the gap, and ensure the stability of the radon accumulation process in the chamber. S4: After the PVC gas collection cylinder 101 is installed, the radon gas measuring device is electrically connected to the soil temperature and humidity sensor 105, the ambient temperature, humidity and pressure sensor 103 pre-installed on the sealing cover of the gas collection cylinder, and the Internet of Things data transmission antenna 104 via cables. The soil radon observation device is then stably fixed inside the bottom of the PVC gas collection cylinder 101. The top sealing cover 102 of the gas collection cylinder is then screwed onto the PVC gas collection cylinder 101 via a threaded interface. The device power interface is connected to the 12V external battery 300 via a cable through the waterproof aviation interface reserved on the sealing cover 102 to complete the power supply. After the device is powered on and started, it is configured according to the preset parameters: the measurement cycle is set to 20 minutes, the single effective measurement duration is set to 5 minutes, and the pulse resolution time is set to 20 ns. After the device is started, it measures the radon gas that diffuses into the ZnS(Ag) scintillation chamber 203 through natural diffusion and records the radon activity concentration data in real time. S5: Repeat steps three to four to complete the deployment and debugging of radon exhalation rate measurement devices at all 20 measurement points within the measurement line; after all measurement point devices are started normally, continuous cumulative measurement is carried out, with a total cumulative measurement time of 24 hours. During this period, each measurement point device completes continuous automatic measurement according to the preset cycle. Through 4G IoT wireless transmission, the radon activity concentration observation data in the ZnS(Ag) scintillation chamber 203 of each measurement point, as well as the synchronously collected environmental parameters such as soil temperature and humidity, ambient temperature, humidity, and air pressure, are transmitted to the remote monitoring platform in real time, ultimately forming a complete time series continuous radon concentration time series dataset for each measurement point; S6: The nonlinear cumulative inversion model was used to analyze the radon concentration variation curves over time at each measuring point. Least squares fitting analysis was performed on the radon concentration time series datasets at each measuring point to calculate the soil radon exhalation rate parameters at 20 measuring points within the measuring line. A soil radon exhalation rate profile curve of the measuring line was plotted, and the spatial distribution characteristics, anomaly amplitude, and continuity of the radon exhalation rate within the measuring line were comprehensively analyzed. Based on the comprehensive identification of regional geological and geophysical data, the potential distribution range of deep concealed sandstone-type uranium ore bodies was identified and predicted.

[0035] Furthermore, the surface conditions in the field survey area are complex and varied. The surface may be covered by different types of vegetation or have differences in root development, as well as differences in surface soil structure caused by different crop topsoil thicknesses and landform types. To reduce the influence of surface environmental factors on the soil radon exhalation rate measurement results, the height of the PVC gas collection cylinder 101 can be uniformly adjusted according to the actual field conditions. By appropriately increasing the burial depth of the gas collection cylinder, the gas diffusion space at its bottom avoids the vegetation root development layer and the disturbed surface soil layer, thereby minimizing the interference of different crop types, surface cover conditions, and micro-topographical differences on the radon exhalation rate measurement, and improving the representativeness and comparability of the measurement results.

[0036] Based on the principle of local static method for measuring surface radon exhalation rate, this method assumes that the radon exhalation rate per unit area remains constant within the observation timescale under closed gas collection conditions, and the radon surface exhalation rate does not change with time. By measuring the cumulative change of radon concentration in the gas collection space over a certain period of time, and combining this with known volume and cover area parameters, the soil radon surface exhalation rate at the corresponding measuring point is calculated. This method is suitable for measuring surface radon flux under short-term stable observation conditions and can more accurately reflect the actual radon exhalation level at the measuring point.

[0037] Example 3, referring to Figures 3-4 This is the third embodiment of the present invention. Unlike the previous embodiment, this embodiment discloses a time series diagram of radon activity concentration nonlinear fitting of radon surface precipitation rate at measuring point H2-01 on a known sandstone-type uranium deposit, and a distribution diagram of radon activity concentration and radon surface precipitation rate at each measuring point along this measuring line.

[0038] like Figure 3 As shown, the radon activity concentration-time series data obtained from the H2-01 measuring point were fitted and analyzed using a nonlinear cumulative radon exhalation rate model. A fitting equation was established based on the kinetics of radon generation, accumulation, and loss within a finite-volume cavity. The parameters of the measured data were optimized using the nonlinear least squares method. The coefficient of determination R after model adjustment was... 2 The coefficient of performance (COP) reached 0.96309, and the fitted curve showed good agreement with the measured data, indicating that the model could accurately reflect the radon accumulation process at this measuring point. The radon surface emission rate at measuring point H2-01 was obtained from the inversion of the fitted parameters as 0.10481 Bq. . m -2. s -1 .

[0039] like Figure 4The figure shows the spatial distribution of radon activity concentration and corresponding radon surface leaching rate at each measuring point along the survey line. Analysis of the available borehole geological data reveals that: measuring points 6–15 have numerous highly mineralized or mineralized boreholes, indicating a high degree of underground uranium mineralization in the corresponding area. The measured radon surface leaching rates at these points are significantly higher, forming a distinct anomaly zone. Measuring points 3–4 correspond to non-mineralized boreholes, showing no obvious mineralization, and their radon activity concentration and radon leaching rate values ​​are relatively low, exhibiting characteristics of a background area. Furthermore, measuring points 17–19 contain one mineralized borehole, indicating a certain degree of mineralization in this area. The radon leaching rate at this point is significantly higher than that at measuring point 20, which is controlled by a non-mineralized borehole, showing a clear spatial response relationship. Overall, the radon leaching rate parameters obtained through nonlinear inversion can effectively characterize the differences in underground uranium source intensity, verifying the feasibility and effectiveness of using radon leaching rate for sandstone-type uranium deposit prospecting.

[0040] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A soil radon exhalation rate measuring device, characterized in that: include, The gas collection mechanism (100) includes a PVC gas collection cylinder (101), the top of which is provided with a sealing cover (102), the top of which is provided with an ambient temperature and humidity pressure sensor (103) and an Internet of Things antenna (104), and the bottom of which is provided with a soil temperature and humidity sensor (105). The detection mechanism (200) is a cylindrical sealed mechanism, including a chip storage module (201), a photon counter (202), a ZnS(Ag) scintillation chamber (203), and a gas diffusion port (204). It also includes a battery (300) for powering the gas collection mechanism (100) and the detection mechanism (200).

2. The soil radon exhalation rate measuring device as described in claim 1, characterized in that: The PVC gas collecting cylinder (101) has a hollow cylindrical structure; The PVC gas collecting cylinder (101) has an external thread structure at the top, and a detachable sealed connection is achieved with the top sealing cap (102) of the gas collecting cylinder through the threaded interface.

3. The soil radon exhalation rate measuring device as described in claim 2, characterized in that: The ambient temperature and humidity pressure sensor (103), IoT antenna (104), soil temperature and humidity sensor (105), and measuring mechanism (200) are all electrically connected to the battery (300).

4. The soil radon exhalation rate measuring device as described in claim 3, characterized in that: The PVC gas collecting cylinder (101) is made of PVC material with a wall thickness of 5mm. A fluororubber sealing ring is installed at the threaded connection between the PVC gas collecting cylinder (101) and the top sealing cap (102) of the gas collecting cylinder.

5. The soil radon exhalation rate measuring device as described in claim 4, characterized in that: The gas diffuser (204) is located on the lower end face of the detection mechanism (200), and a hydrophobic filter membrane is provided inside the gas diffuser (204).

6. The soil radon exhalation rate measuring device as described in claim 5, characterized in that: The ZnS(Ag) scintillation chamber (203) is connected to the internal space of the PVC gas collection cylinder (101) through a gas diffuser (204).

7. The soil radon exhalation rate measuring device as described in claim 6, characterized in that: The inner wall of the ZnS(Ag) scintillation chamber (203) is uniformly coated with a ZnS(Ag) scintillator coating to convert alpha particles generated by the decay of radon and its progeny into visible light photons.

8. The soil radon exhalation rate measuring device as described in claim 7, characterized in that: The photon counter (202) is arranged in relation to the ZnS(Ag) scintillation chamber (203) to convert visible light photons into electrical pulse signals and transmit them to the chip storage module (201).

9. The soil radon exhalation rate measuring device as described in claim 8, characterized in that: The chip storage module (201) is used to set measurement parameters, convert pulse signals into radon activity concentration, synchronously store measurement data and environmental parameters, in-situ invert soil radon release rate based on a preset nonlinear cumulative inversion model, and realize remote data transmission through an Internet of Things antenna (104).

10. A method for measuring soil radon exhalation rate in sandstone-type uranium deposit prospecting, characterized in that: The method comprising the soil radon exhalation rate measuring device according to any one of claims 1 to 9 includes the following steps: S1: Collect and organize geological data of the area to be explored, combine ground geophysical data, well logging data and existing mineralization information, conduct a comprehensive evaluation of the mineralization prospect, and select sandstone-type uranium mineralization prospect areas as key target areas; S2: Within the selected target area, based on the orientation of the ore-bearing sand body and the distribution characteristics of the ore-controlling structures, measuring points are set up according to the preset spacing between measuring points and measuring lines to form a soil radon exhalation rate observation network covering the target area. S3: Drill vertical holes at each measuring point that match the outer diameter of the PVC gas collecting cylinder (101), and vertically and stably bury the PVC gas collecting cylinder (101) in the borehole, ensuring that its bottom opening is in full contact with the original soil at the bottom of the hole without gaps, and the probe of the soil temperature and humidity sensor (105) is completely inserted into the soil at the bottom of the hole. Use the original soil taken out of the borehole to backfill the annular gap between the outer wall of the gas collecting cylinder and the hole wall and compact it in layers. S4: Complete the electrical connection between the radon gas measuring device and the soil temperature and humidity sensor (105), the ambient temperature, humidity and pressure sensor (103), the Internet of Things antenna (104), and the external battery (300). Fix the radon gas measuring device inside the PVC gas collecting cylinder (101), tighten the sealing cap (102) on the top of the gas collecting cylinder to form a sealed cavity. After the device is powered on, continuously measure and record the radon activity concentration according to the preset measurement parameters. S5: Complete the deployment and debugging of devices at all measuring points within the target area, and collect the time series dataset of radon activity concentration at each measuring point in real time through IoT wireless transmission, and simultaneously collect and store the atmospheric and soil temperature, humidity, and air pressure environmental parameters of the corresponding measuring points. S6: The nonlinear cumulative inversion model is used to fit and analyze the time series data of radon concentration at each measuring point, and the soil radon release rate parameters at each measuring point are obtained by inversion. The spatial distribution characteristics, anomalous amplitude and continuity of radon release rate in the target area are comprehensively analyzed to identify the abnormal area of ​​soil radon release rate, so as to realize the identification and prediction of the potential distribution range of deep concealed sandstone-type uranium ore bodies.

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