Small-flow discontinuous underground water radon concentration real-time monitoring system and method

Abstract

The invention provides a small-flow discontinuous underground water radon concentration real-time monitoring system and method, and the system comprises a cabinet body, a radon concentration measurement device, and a drainage convergence device which comprises a drainage pipe, a water catchment cavity, and a water valve. The integrated measuring device comprises a central cylinder which is connected with a third air inlet pipe, a third air outlet pipe and a third water drainage pipe, and the horizontal included angle between every two adjacent air inlet pipes and the third water drainage pipe is 90 degrees. A disc cylinder; a first water inlet pipe, a first air outlet pipe, a first air inlet pipe, a fourth water drainage pipe and an exhaust mechanism are arranged on each water collection bottle; when the disc cylinder rotates, the four water collecting bottles are in different states, and only the first water inlet pipe of the water collecting bottles in the water collecting state is located under the water outlet pipe. The first air outlet pipe and the third air outlet pipe of the water collecting bottle in the measuring state are communicated, and the first air inlet pipe and the third air inlet pipe are communicated; the fourth drainage pipe of the water collection bottle in the drainage state is communicated with the third drainage pipe. According to the application, small-flow discontinuous water samples can be converged, collected and detected.

Description

Technical Field

[0001] The present application relates to the field of nuclear radiation detection technology, and in particular to a real-time monitoring system and method for small-flow discontinuous groundwater radon concentration. Background Art

[0002] radon( 222 Rn) is a radioactive isotope that is widely distributed in the air, rock, soil and water in the environment. It is a colorless, odorless, water-soluble inert gas.

[0003] Geological disasters such as landslides, earthquakes, cavern collapses, etc. caused by artificial or natural factors pose a great threat to the safety of human life and property. In these geological disasters, water (such as rainfall, periodic changes in reservoir water levels, fault excess pore water pressure, etc.) often plays a key inducing role; at the same time, groundwater is the main carrier of rock and soil material transmission, and the physical and chemical parameters of groundwater are important indicators of rock and soil evolution. In particular, abnormal changes in radon concentration in groundwater often indicate the evolution of the internal structure of the rock and soil, and can be used as an important early warning indicator of geological disasters.

[0004] In addition, with the further development of my country's infrastructure and excavation technology, the scale and number of tunnels and underground caverns have increased exponentially. Since such underground structures are highly airtight and have poor ventilation conditions, they will face the problem of radon gas enrichment during the excavation and use stages. High concentrations of radon gas seriously endanger the health of personnel, so the concentration of radon in tunnel groundwater is an important safety indicator. Whether it is a landslide, an earthquake process, or the excavation of an underground cavern, the rock or soil will be deformed, damaged, or even destroyed. The radon gas stored will be released into the surrounding groundwater as the rock and soil are deformed and destroyed, causing significant changes in the radon concentration in the water flowing through the rock and soil. However, due to the different permeabilities of different rock and soil bodies and the seasonal differences in atmospheric precipitation, the flow of water samples will have temporal and spatial differences. Therefore, long-term monitoring of radon in water needs to face this situation of small discontinuous flows.

[0005] On the one hand, water samples exposed in some dense rock and soil bodies often show dripping. In order to prevent the radon gas in the water from escaping due to dripping, water samples need to be collected near the water outcropping point. Generally, such water sample collection needs to be done manually. For the collection and measurement work that lasts for several years, the labor cost is extremely high. Moreover, the water body monitoring points are often in the field. Due to the non-uniformity of groundwater flow in time, it is often difficult to ensure the timeliness of water sample collection and the real-time measurement manually. In addition, the data collection density of long-term monitoring is low, which is very unfavorable for the long-term monitoring of radon.

[0006] On the other hand, the existing long-term monitoring methods of radon concentration in water bodies, in addition to the above-mentioned manual collection and monitoring, often use continuous water as the monitoring object, release the water sample through the nozzle by pumping, and release the radon gas from the water body for measurement. This has certain requirements for the flow rate of the water sample, and often requires a continuous flow rate to meet the real-time and uninterrupted monitoring of radon gas in groundwater. Another method of monitoring radon concentration by considering the concentration balance of radon in water and radon in the air can ignore the continuity of water flow, but this monitoring method also has certain flow requirements, and it is necessary to completely update the water body in the device once within a period of time, and the response time to the change of radon concentration is long, so there may be a lag in the sudden change of radon concentration, which is very unfavorable for the prediction and early warning of earthquakes and landslides. Summary of the invention

[0007] In order to improve the problem that radon concentration in small-flow groundwater is difficult to detect efficiently, the present application provides a real-time monitoring system and method for radon concentration in small-flow discontinuous groundwater.

[0008] In the first aspect, the present application provides a small flow discontinuous groundwater radon concentration real-time monitoring system, which adopts the following technical solutions: A real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate, comprising a cabinet and a radon concentration measuring device, and also comprising: A drainage and converging device, comprising: A drainage tube, including a trumpet-shaped opening and a drainage tube; A water collection chamber is provided at the top of the cabinet and is used to receive water falling from the drainage pipe; and A water valve, comprising a movable ball valve and a water outlet pipe connected to the water collection chamber; The integrated measuring device comprises: A central cylinder, on which are connected a third air inlet pipe, a third air outlet pipe and a third drain pipe, the horizontal angle between which is 90° between the adjacent two pipes, the bottom end of the third air inlet pipe is connected to the output end of the radon concentration measuring device, and the bottom end of the third air outlet pipe is connected to the input end of the radon concentration measuring device; A disc cylinder, rotatably disposed on the circumference of the central cylinder; and There are four water collecting bottles, which are evenly spaced on the disc cylinder, and the water collecting bottles are provided with a first water inlet pipe, a first air outlet pipe, a first air inlet pipe, a fourth water discharge pipe and an exhaust mechanism; When the disc cylinder rotates, the four water collecting bottles are in different states. The water collecting bottle in the water collecting state has only its first water inlet pipe located directly below the water outlet pipe; the first air outlet pipe of the water collecting bottle in the measuring state is connected with the third air outlet pipe, and the first air inlet pipe is connected with the third air inlet pipe; the fourth drain pipe of the water collecting bottle in the draining state is connected with the third drain pipe.

[0009] Furthermore, four second air inlet pipes, a second air outlet pipe and a second drain pipe are arranged on the disc cylinder, the four second air inlet pipes are respectively connected to the four first air outlet pipes in a one-to-one correspondence, the four second air outlet pipes are respectively connected to the four first air inlet pipes in a one-to-one correspondence, and the four second drain pipes are respectively connected to the four fourth drain pipes in a one-to-one correspondence; The horizontal angle between the second air inlet pipe, the second air outlet pipe and the second drain pipe is 90°; The second air inlet pipe has the same horizontal height as the top end of the third air outlet pipe, the second air outlet pipe has the same horizontal height as the top end of the third air inlet pipe, and the second drain pipe has the same horizontal height as the top end of the third drain pipe.

[0010] Furthermore, the outer peripheral wall of the central cylinder is wrapped with a sealing waterproof layer, and the sealing waterproof layer is provided with a first opening connected to the top end of the third air outlet pipe, and the aperture of the first opening is smaller than the diameter of the second air inlet pipe; The sealing waterproof layer is provided with a second opening connected to the top end of the third air inlet pipe, and the diameter of the second opening is smaller than the diameter of the second air outlet pipe; The sealing waterproof layer is provided with a third opening connected to the top end of the third drainage pipe, and the diameter of the third opening is smaller than the diameter of the second drainage pipe.

[0011] Furthermore, the first water inlet pipe, the first air inlet pipe, the first air outlet pipe and the fourth drain pipe are all provided with a one-way valve; The one-way valve on the first water inlet pipe has a passage direction from top to bottom, the one-way valve outside the first air inlet pipe has a passage direction from outside the bottle to inside the bottle, the one-way valve on the first air outlet pipe has a passage direction from inside the bottle to outside the bottle, and the one-way valve on the fourth drain pipe has a passage direction from inside the bottle to outside the bottle.

[0012] Furthermore, the exhaust mechanism includes an exhaust movable valve arranged on the top of the water collecting bottle, the exhaust movable valve is provided with at least two outwardly protruding exhaust holes on the top, a rubber cylinder is slidably arranged inside, and an intermediate opening is opened in the middle of the rubber cylinder, which is staggered with the multiple outwardly protruding exhaust holes.

[0013] Furthermore, one end of the first air inlet pipe extending into the water collecting bottle is connected to a porous glass rod.

[0014] Furthermore, a second stepper motor and a water collection full load signal processing device are arranged in the cabinet, and an output end of the second stepper motor is transmission-connected to the disc cylinder; The water collection full load signal processing device comprises: A measuring cylinder, wherein an extension port is provided on a side of the top end close to the disc cylinder, an overflow port is provided on a side of the top end of the first water inlet pipe away from the central cylinder, and the extension port is located below the overflow port on the water collecting bottle in a water collecting state; a first pressure sensor, mounted on the inner wall of the measuring cylinder and control-connected to the second stepping motor; and The first drainage pipe is connected to the side wall of the bottom end of the measuring cylinder, and the maximum drainage flow rate of the first drainage pipe is 0.045 ml / min.

[0015] Furthermore, the radon concentration measuring device includes a cylindrical drying tube and a radon monitor, the air inlet of the cylindrical drying tube is connected to the third air outlet, the air outlet is connected to the air inlet of the radon monitor, and the air outlet of the radon monitor is connected to the third air inlet.

[0016] Furthermore, the cabinet is connected with a drain port on one side of the top of the water collecting chamber.

[0017] In a second aspect, the present application provides a method for real-time monitoring of radon concentration in discontinuous groundwater with a small flow rate, based on the above-mentioned real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate, comprising the following steps: S1. The trumpet-shaped opening of the drainage tube is fixed directly below the exposed water sample, and the lower end of the drainage tube is placed in the water collection cavity; S2. The water sample flows through the water valve to the first water inlet pipe of the water collecting bottle in the water collecting state, and is stored in the water collecting bottle; at this time, the first air outlet pipe, the first air inlet pipe and the fourth water discharge pipe on the water collecting bottle do not form a passage with the central cylinder, the gas in the water collecting bottle is discharged through the exhaust mechanism, and the water level in the bottle continues to rise; S3. When the water level in the water collecting bottle in step S2 reaches the set value, the disc cylinder is driven to rotate 90 degrees, the water collecting bottle enters the measuring state, the first air outlet pipe is connected with the third air outlet pipe, the first air inlet pipe is connected with the third air inlet pipe, the radon gas escaped from the water collecting bottle enters the radon concentration measuring device for radon concentration detection, and the gas after the detection is completed flows back to the water collecting bottle through the third air inlet pipe and the first air inlet pipe; S4. When the radon concentration detection in the water collection bottle in step S3 is completed, the disc cylinder is driven to continue to rotate 90° in the same direction, the water collection bottle enters the drainage state, and the fourth drain pipe is connected to the third drain pipe, and the water level in the bottle continues to drop; S5. Continue to drive the disc cylinder to rotate 90° in the same direction each time, so that each water collecting bottle on the disc cylinder undergoes steps S2 to S4 in sequence, thereby achieving real-time monitoring of radon concentration in small-flow discontinuous water samples.

[0018] In summary, the present application includes at least one of the following beneficial technical effects: 1. The present application uses multiple drainage tubes on the drainage and convergence device to converge and collect small-flow discontinuous water samples, while also reducing the radon gas emission caused by dripping; 2. The present application sequentially rotates the disc and cylinder in the integrated collection and measurement device by 90°, so that each water collection bottle can sequentially experience the water collection state, measurement state, drainage state and idle state, and repeat the cycle, so as to realize automatic water sample collection, monitoring and discharge, thereby reducing labor costs and effectively improving the timeliness of water sample collection and monitoring; 3. This application can realize the radon concentration monitoring of discontinuous groundwater with small flow rate. The flow rate required for continuous radon measurement in general water bodies is 2-3L / min. The water flow rate used in this application only needs to meet the collection of full water bottles before radon decay, that is, greater than 0.045 ml / min, which significantly expands the flow range of measured water samples; 4. This application uses an integrated device to automatically collect water for radon measurement. Compared with the discontinuous water sample measurement method using water vapor balance, the response time is significantly improved. Generally, the fastest radon water vapor balance time is about 2 hours, while the fastest time to complete a set of measurements in this application is about 30 minutes; 5. This application can realize the remote transmission and real-time analysis of radon concentration data by setting up control and data collection devices, and can also remotely control the operation of the entire system, and can promptly detect and stop monitoring when the instrument fails; 6. This application is a modular system. The detachable power supply can realize long-term water sample radon concentration monitoring in the field. At the same time, some batteries can be replaced without power outage without affecting the normal operation of the system. The detachable and replaceable radon monitor is easy to maintain and can also reduce system downtime through direct replacement. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application; Figure 2 is a front cross-sectional structural schematic diagram of the integrated measurement device of an embodiment of the present application; Figure 3 is a schematic side cross-sectional view of the integrated measurement device according to an embodiment of the present application; Figure 4 yes Figure 3The top view of the integrated measuring device, the cross-sectional top view along line ⅠⅠ', the cross-sectional top view along line ⅡⅡ', and the cross-sectional top view along line ⅢⅢ'; Figure 5 It is a schematic diagram of the structure of the water collecting bottle of the embodiment of the present application.

[0021] Reference numerals: 1. Drainage and convergence device; 11. Drainage pipe; 111. Trumpet-shaped opening; 112. Drainage pipe; 12. Water collection chamber; 121. Drainage outlet; 122. Concave basin; 13. Water valve; 131. Movable ball valve; 132. Water outlet pipe; 14. Steel crawler track; 2. Integrated measurement device; 21. Water collection full load signal processing device; 211. First drainage pipe; 212. First pressure sensor; 213. Measuring cylinder; 22, disc cylinder; 221, second air inlet pipe; 222, second air outlet pipe; 223, second drain pipe; 23, central cylinder; 231, sealing waterproof layer; 232, third air inlet pipe; 233, third air outlet pipe; 234, third drainage pipe; 235, third opening; 236, first opening; 237, second opening; 24, water collecting bottle; 241, first water inlet pipe; 242, exhaust movable valve; 2421, external convex exhaust hole; 2422, rubber cylinder; 243, first air outlet pipe; 244, first air inlet pipe; 2441, porous glass rod; 245, one-way valve; 246, fourth drain pipe; 3. Radon concentration measuring device; 31. Cylindrical drying tube; 32. Radon monitoring instrument; 4. Control and data collection device; 41. Wireless signal receiving and transmitting device; 42. Wireless data acquisition device; 43. Host; 44. Display; 5. First stepper motor; 6. Power supply; 7. Second stepper motor; 8. Cabinet. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] Reference Figure 1 and Figure 2The embodiment of the present application discloses a real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate, which includes a cabinet 8 and a radon concentration measuring device 3. The cabinet 8 is made of a transparent sealing material as a whole and has good sealing performance and structural strength.

[0024] Also includes: The drainage and converging device 1 comprises: The drainage tube 112 includes a trumpet-shaped opening 111 and a drainage tube 112; The water collecting chamber 12 is provided at the top of the cabinet 8 and is used to receive the water falling from the drainage pipe 112. The water collecting chamber 12 includes a concave basin 122 provided on the top of the cabinet 8 and a drain port 121 connected to one side of the top of the concave basin 122. When the water flow in the water collecting chamber 12 is too large, the water will be discharged from the drain port 121; and The water valve 13 includes a movable ball valve 131 and a water outlet pipe 132 connected to the water collecting chamber 12. A first stepper motor 5 is also provided in the cabinet 8. The movable ball valve 131 is connected to the output end of the first stepper motor 5 through a stainless steel track, and the first stepper motor 5 can control the rotation of the movable ball valve 131 to realize the opening and closing of the water valve 13.

[0025] Integrated measuring device 2, refer to Figure 2 and Figure 3 , which includes: The central cylinder 23 is connected with a third air inlet pipe 232, a third air outlet pipe 233 and a third drain pipe 234, the bottom end of the third air inlet pipe 232 is connected to the output end of the radon concentration measuring device 3, and the bottom end of the third air outlet pipe 233 is connected to the input end of the radon concentration measuring device 3; The disc cylinder 22 is rotatably disposed on the circumference of the central cylinder 23. Specifically, the disc cylinder 22 is separated from the central cylinder 23, and the upper and lower ends of the central cylinder 23 and the disc cylinder 22 are fixed by bearings; and There are four water collecting bottles 24 fixedly mounted on the disc cylinder 22 at equal intervals. The water collecting bottles 24 are provided with a first water inlet pipe 241, a first air outlet pipe 243, a first air inlet pipe 244, a fourth drain pipe 246 and an exhaust mechanism.

[0026] Reference Figure 3 and Figure 4 When the disc cylinder 22 rotates, the four water collecting bottles 24 are in different states. The water collecting bottle 24 in the water collecting state has only its first water inlet pipe 241 located directly below the water outlet pipe 132; the first air outlet pipe 243 of the water collecting bottle 24 in the measuring state is connected with the third air outlet pipe 233, and the first air inlet pipe 244 is connected with the third air inlet pipe 232; the fourth drain pipe 246 of the water collecting bottle 24 in the draining state is connected with the third drain pipe 234; the water collecting bottle 24 in the idle state is not connected with the water outlet pipe 132 and the central cylinder 23.

[0027] The four water collecting bottles 24 are all connected to the disc cylinder 22 and their positions are relatively fixed. Specifically, the disc cylinder 22 is provided with four second air inlet pipes 221, second air outlet pipes 222 and second drainage pipes 223. The four second air inlet pipes 221 are respectively connected to the four first air outlet pipes 243 in a one-to-one correspondence, the four second air outlet pipes 222 are respectively connected to the four first air inlet pipes 244 in a one-to-one correspondence, and the four second drainage pipes 223 are respectively connected to the four fourth drainage pipes 246 in a one-to-one correspondence. The horizontal angle between the second air inlet pipe 221, the second air outlet pipe 222 and the second drain pipe 223 is 90°; The second air inlet pipe 221 and the third air outlet pipe 233 have the same top level, the second air outlet pipe 222 and the third air inlet pipe 232 have the same top level, and the second drain pipe 223 and the third drain pipe 234 have the same top level.

[0028] In addition, the outer wall of the central cylinder 23 is wrapped with a sealing waterproof layer 231, and the position of the sealing waterproof layer 231 and the central cylinder 23 are relatively fixed. The second air inlet pipe 221, the second air outlet pipe 222 and the second drain pipe 223 on the disc cylinder 22 are close to the end of the central cylinder 23 and are tightly fitted with the outer wall of the sealing waterproof layer 231, and can slide relative to the sealing waterproof layer 231. The sealing waterproof layer 231 is an elastic sealing material with good airtightness and wear resistance, such as butyl rubber or polyurethane rubber.

[0029] The sealing waterproof layer 231 is provided with a first opening 236 communicating with the top end of the third air outlet pipe 233 , and the diameter of the first opening 236 is smaller than the diameter of the second air inlet pipe 221 ; The sealing waterproof layer 231 is provided with a second opening 237 communicating with the top end of the third air inlet pipe 232, and the diameter of the second opening 237 is smaller than the diameter of the second air outlet pipe 222; The sealing waterproof layer 231 is provided with a third opening 235 which is connected with the top end of the third drainage pipe 234 . The diameter of the third opening 235 is smaller than the diameter of the second drainage pipe 223 .

[0030] Among them, the first opening 236, the second opening 237 and the third opening 235 are respectively aligned with the second air inlet pipe 221, the second air outlet pipe 222 and the second drainage pipe 223 in vertical height, and the adjacent openings are spaced 90° apart in horizontal distribution, and are respectively aligned with the horizontal distribution positions of the four water collecting bottles 24 on the disc cylinder 22.

[0031] In addition, a check valve 245 is provided on the first water inlet pipe 241, the first air inlet pipe 244, the first air outlet pipe 243 and the fourth drain pipe 246; The one-way valve 245 on the first water inlet pipe 241 has a passage direction from top to bottom, the one-way valve 245 outside the first air inlet pipe 244 has a passage direction from outside the bottle to inside the bottle, the one-way valve 245 on the first air outlet pipe 243 has a passage direction from inside the bottle to outside the bottle, and the one-way valve 245 on the fourth drain pipe 246 has a passage direction from inside the bottle to outside the bottle.

[0032] Further, see Figure 1 The radon concentration measuring device 3 includes a cylindrical drying tube 31 and a radon monitor 32. The cylindrical drying tube 31 is made of transparent acrylic material. The desiccant in the cylindrical drying tube 31 is anhydrous copper sulfate with an indication function. The air inlet of the cylindrical drying tube 31 is connected to the third air outlet pipe 233, and the air outlet is connected to the air inlet of the radon monitor 32. The air outlet of the radon monitor 32 is connected to the third air inlet pipe 232 to form a closed loop. The radon monitor 32 contains a micro pump, and the radon monitor 32 can receive wireless signals to control the micro pump switch and measurement.

[0033] In addition, refer to Figure 5 The exhaust mechanism includes an exhaust movable valve 242 disposed on the top of the water collection bottle 24, the top of the exhaust movable valve 242 is provided with at least two convex exhaust holes 2421, a rubber cylinder 2422 is slidably disposed inside, and a middle opening is opened in the middle of the rubber cylinder 2422, which is staggered with the multiple convex exhaust holes 2421; wherein the diameter of the rubber cylinder 2422 is slightly smaller than the inner diameter of the shell of the exhaust movable valve 242, the diameter of the middle opening of the rubber cylinder 2422 is smaller than the net distance between the two convex exhaust holes 2421, the density of the rubber cylinder 2422 is smaller than that of water, and the rubber cylinder 2422 can move up and down in the exhaust movable valve 242 due to the buoyancy of water. And one end of the first air inlet pipe 244 extending into the water collection bottle 24 is connected to a porous glass rod 2441, and the setting of the porous glass rod 2441 can increase the contact between the gas pumped into the radon monitor 32 and the water in the water collection bottle 24.

[0034] And, for automatic measurement, refer to Figure 1 and Figure 2 A second stepper motor 7 and a water collection full load signal processing device 21 are arranged in the cabinet 8. The output end of the second stepper motor 7 is connected to the disc cylinder 22 by transmission. Specifically, the output end of the second stepper motor 7 is connected to the disc cylinder 22 by a steel track 14, and the rotation angle of the disc cylinder 22 can be controlled by the second stepper motor 7.

[0035] The water collection full load signal processing device 21 comprises: The measuring cylinder 213 has an extension opening at its top end near the disc cylinder 22, and an overflow opening is provided at the top end of the first water inlet pipe 241 away from the central cylinder 23, and the extension opening is located below the overflow opening on the water collecting bottle 24 in the water collecting state; A first pressure sensor 212 is mounted on the inner wall of the measuring cylinder 213 and is control-connected to both the second stepping motor 7 and the first stepping motor 5; and The first drain pipe 211 is connected to the side wall of the bottom end of the measuring cylinder 213, and the maximum drainage flow rate of the first drain pipe 211 is 0.045 ml / min. The purpose of setting the first drain pipe 211 as a small flow pipeline is to appropriately prolong the time that the water collecting bottle 24 in the water collecting state is in this state, so as to be close to the time spent by the water collecting bottle 24 in the measuring state and the drainage state, so as to avoid the situation where the water collecting bottle 24 in the water collecting state is full, while the water collecting bottle 24 in the measuring state and the drainage state has not completed the measurement and drainage process, and the second stepper motor 7 controls the disc cylinder 22 to rotate to switch the state, which affects the detection quality and subsequent processes.

[0036] Specifically, refer to Figure 1 A control and data collection device 4 is arranged in the cabinet 8, and the control and data collection device 4 includes a wireless data collector, a wireless signal receiving and transmitting device 41, a host 43, a display 44 and a power supply 6; the power supply 6 supplies power to the integrated measurement device 2, the radon concentration measuring device 3, and the control and data collection device 4 respectively; the power supply 6 is a plurality of batteries, which are arranged to be detachable batteries, and a single battery can be replaced without power outage.

[0037] Thus, the central cylinder 23 and the disc cylinder 22 are connected in such a way that after the disc cylinder 22 rotates, the water collecting bottles 24 at different positions are in different passages, as shown in FIG. Figure 4 .by Figure 2 Taking the arrangement of the middle water collection bottle 24 as an example, the first air outlet pipe 243, the first air inlet pipe 244 and the fourth water discharge pipe 246 of the water collection bottle 24 on the left side of the disc cylinder 22 do not form a passage with the central cylinder 23. At this time, the water sample flows into the water collection bottle 24 from the first water inlet pipe 241 through the water outlet pipe 132, and it is in a state of collecting water samples, which is called the water collection state; while the water collection bottle 24 at the rear end of the disc cylinder 22 (such as Figure 3 The first air outlet pipe 243 and the first air inlet pipe 244 of the water collecting bottle 24 on the left side of the middle (as shown in the figure) form a passage with the central cylinder 23 through the first opening 236 and the second opening 237 respectively, and are connected to the radon concentration measuring device 3, and the first drain pipe 211 does not form a passage and is in a radon gas measurement state, which is called the measurement state; while the first air outlet pipe 243 and the first air inlet pipe 244 of the water collecting bottle 24 at the right end of the disc cylinder 22 do not form a passage with the central cylinder 23, but the first drain pipe 211 forms a passage with the third opening 235 and is in a drainage state.

[0038] In specific operation, when the first pressure sensor 212 sends a signal to the water collecting bottle 24 in the water collecting state, it means that the water sample collection is completed; when the radon concentration measuring device 3 sends radon concentration data to the water collecting bottle 24 in the measuring state, it means that the measurement is completed, and the general time setting is not more than 30 minutes; the water collecting bottle 24 in the drainage state sets the minimum drainage flow rate by controlling the aperture size of the third drainage pipe 234, the third opening 235 and the second drainage pipe 223 to ensure that the drainage is completed within 25 minutes. When and only when the water collecting bottle 24 in the water collecting state and the water collecting bottle 24 in the measuring state are completed, the control and data collection device 4 will send a rotation signal to the second stepping motor 7 to drive the disc cylinder 22 to rotate to switch the state of the water collecting bottle 24. At the same time, during the rotation of the disc cylinder 22, the control and data collection device 4 will also send a rotation signal to the first stepper motor 5, so that the first stepper motor 5 drives the movable ball valve 131 to rotate to close the water valve 13; when the disc cylinder 22 is rotated to the right position, the control and data collection device 4 will send a rotation signal to the first stepper motor 5 again, so that the first stepper motor 5 drives the movable ball valve 131 to rotate in the opposite direction to open the water valve 13.

[0039] Since the sealing waterproof layer 231 has holes only at specific positions, when each water collecting bottle 24 switches its state, a passage is formed only when it reaches the water collecting bottle 24 at the corresponding hole. During the switching process, the first air outlet pipe 243, the first air inlet pipe 244 and the fourth drain pipe 246 of the water collecting bottle 24 remain sealed at all times; the sealing waterproof layer 231 is tightly filled between the disc cylinder 22 and the central cylinder 23 to ensure the sealing of the sealing waterproof layer 231 at the position without holes.

[0040] Furthermore, the disc cylinder 22 rotates clockwise under the drive of the second stepper motor 7, and each water collecting bottle 24 sequentially undergoes four processes of collecting water samples, measuring radon concentration, draining and idling, and the cycle repeats; among them, the third drain pipe 234, the third opening 235, the second drain pipe 223 and the pipeline connecting the three must meet the minimum drainage flow rate of 25 ml / min.

[0041] The embodiment of the present application also discloses a method for real-time monitoring of radon concentration in discontinuous groundwater with a small flow rate. Based on the above-mentioned real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate, the following technical solution is adopted: A method for real-time monitoring of radon concentration in discontinuous groundwater with a small flow rate comprises the following steps: S1. Fix the trumpet-shaped opening 111 of the drainage tube 112 just below the exposed water sample, and place the lower end of the drainage tube 112 in the water collection chamber 12; if there are multiple exposed points in the same small area, multiple drainage tubes 112 can be used to collect all the water samples into the water collection chamber 12.

[0042] S2. The water sample flows through the water valve 13 to the first water inlet pipe 241 of the water collecting bottle 24 in the water collecting state, and is stored in the water collecting bottle 24; at this time, the first air outlet pipe 243, the first air inlet pipe 244 and the fourth water discharge pipe 246 on the water collecting bottle 24 do not form a passage with the central cylinder 23, and the gas in the water collecting bottle 24 is discharged through the exhaust mechanism, and the water level in the bottle continues to rise.

[0043] S3. When the water level in the water collecting bottle 24 in step S2 reaches the set value and is detected by the first pressure sensor 212, the second stepper motor 7 is controlled to drive the disc cylinder 22 to rotate 90°, and the water collecting bottle 24 enters the measuring state. The first air outlet pipe 243 is connected with the third air outlet pipe 233, and the first air inlet pipe 244 is connected with the third air inlet pipe 232. The radon gas escaped from the water collecting bottle 24 enters the radon concentration measuring device 3 for radon concentration detection. After the detection, the gas is pumped by the micro pump contained in the radon monitor 32 through the third air inlet pipe 232 and the first air inlet pipe 244 to return to the water collecting bottle 24 to maintain the air pressure balance in the water collecting bottle 24 and promote the precipitation of radon gas in the water. And during the radon concentration detection process, the wireless data collector records the date and time when the second stepper motor 7 completes rotation, the wireless signal receiving transmitter 41 sends a pump operation signal to the radon monitor 32, the radon monitor 32 pumps gas into the water collecting bottle 24, and carries the radon gas in the water body of the water collecting bottle 24 into the radon monitor 32, starts to measure the radon concentration, and records the measurement results. The monitoring time of the radon concentration in the water body takes 30 minutes.

[0044] S4. After the radon gas concentration detection in the water collection bottle 24 in step S3 is completed, the disc cylinder 22 is driven to continue to rotate 90° in the same direction, and the water collection bottle 24 enters the drainage state, and its fourth drainage pipe 246 is connected to the third drainage pipe 234, and the water level in the bottle continues to drop.

[0045] S5. Continue to drive the disc cylinder 22 to rotate 90° in the same direction each time in steps, so that each water collecting bottle 24 on the disc cylinder 22 undergoes steps S2 to S4 in sequence and repeats the cycle to achieve real-time monitoring of radon concentration in small-flow discontinuous water samples; wherein the starting mechanism for the disc cylinder 22 to rotate 90° each time is based on the fact that the water in the water collecting bottle 24 in each water collecting state is full and overflows into the measuring cylinder 213, which is controlled by the water collecting full load signal processing device 21, and the radon concentration measuring device 3 is also required to send a measurement completion signal, and the two are synchronously controlled; and, during the rotation of the disc cylinder 22, the first stepper motor 5 is also controlled to drive the movable ball valve 131 to rotate to close the water valve 13, and after the disc cylinder 22 rotates into place, the first stepper motor 5 is controlled to drive the movable ball valve 131 to rotate in the opposite direction to open the water valve 13.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate, comprising a cabinet and a radon concentration measuring device, characterized in that: Also includes: A drainage and converging device, comprising: A drainage tube, including a trumpet-shaped opening and a drainage tube; A water collection chamber is provided at the top of the cabinet and is used to receive water falling from the drainage pipe; and A water valve, comprising a movable ball valve and a water outlet pipe connected to the water collection chamber; The integrated measuring device comprises: A central cylinder, on which are connected a third air inlet pipe, a third air outlet pipe and a third drain pipe, the horizontal angle between which is 90° between the adjacent two pipes, the bottom end of the third air inlet pipe is connected to the output end of the radon concentration measuring device, and the bottom end of the third air outlet pipe is connected to the input end of the radon concentration measuring device; A disc cylinder, rotatably disposed on the circumference of the central cylinder; and There are four water collecting bottles, which are evenly spaced on the disc cylinder, and the water collecting bottles are provided with a first water inlet pipe, a first air outlet pipe, a first air inlet pipe, a fourth water discharge pipe and an exhaust mechanism; When the disc cylinder rotates, the four water collecting bottles are in different states. The water collecting bottle in the water collecting state has only its first water inlet pipe located directly below the water outlet pipe; the first air outlet pipe of the water collecting bottle in the measuring state is connected with the third air outlet pipe, and the first air inlet pipe is connected with the third air inlet pipe; the fourth drain pipe of the water collecting bottle in the draining state is connected with the third drain pipe.

2. A real-time monitoring system for low-flow discontinuous groundwater radon concentration according to claim 1, characterized in that: The disc cylinder is provided with four second air inlet pipes, a second air outlet pipe and a second drain pipe, the four second air inlet pipes are respectively connected to the four first air outlet pipes in a one-to-one correspondence, the four second air outlet pipes are respectively connected to the four first air inlet pipes in a one-to-one correspondence, and the four second drain pipes are respectively connected to the four fourth drain pipes in a one-to-one correspondence; The horizontal angle between the second air inlet pipe, the second air outlet pipe and the second drain pipe is 90°; The second air inlet pipe has the same horizontal height as the top end of the third air outlet pipe, the second air outlet pipe has the same horizontal height as the top end of the third air inlet pipe, and the second drain pipe has the same horizontal height as the top end of the third drain pipe.

3. A real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate according to claim 2, characterized in that: The outer peripheral wall of the central cylinder is wrapped with a sealing waterproof layer, and the sealing waterproof layer is provided with a first opening connected to the top end of the third air outlet pipe, and the aperture of the first opening is smaller than the diameter of the second air inlet pipe; The sealing waterproof layer is provided with a second opening connected to the top end of the third air inlet pipe, and the diameter of the second opening is smaller than the diameter of the second air outlet pipe; The sealing waterproof layer is provided with a third opening connected to the top end of the third drainage pipe, and the diameter of the third opening is smaller than the diameter of the second drainage pipe.

4. A small flow discontinuous groundwater radon concentration real-time monitoring system according to claim 1, characterized in that: The first water inlet pipe, the first air inlet pipe, the first air outlet pipe and the fourth drain pipe are all provided with a one-way valve; The one-way valve on the first water inlet pipe has a passage direction from top to bottom, the one-way valve outside the first air inlet pipe has a passage direction from outside the bottle to inside the bottle, the one-way valve on the first air outlet pipe has a passage direction from inside the bottle to outside the bottle, and the one-way valve on the fourth drain pipe has a passage direction from inside the bottle to outside the bottle.

5. A real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate according to claim 1, characterized in that: The exhaust mechanism includes an exhaust movable valve arranged on the top of the water collecting bottle, the top of the exhaust movable valve is provided with at least two outwardly protruding exhaust holes, a rubber cylinder is slidably arranged inside, and a middle opening is opened in the middle of the rubber cylinder and is staggered with multiple outwardly protruding exhaust holes.

6. A small flow discontinuous groundwater radon concentration real-time monitoring system according to claim 1, characterized in that: One end of the first air inlet pipe extending into the water collecting bottle is connected to a porous glass rod.

7. A real-time monitoring system for low-flow discontinuous groundwater radon concentration according to any one of claims 1 to 6, characterized in that: A second stepper motor and a water collection full load signal processing device are arranged in the cabinet, and an output end of the second stepper motor is transmission-connected to the disc cylinder; The water collection full load signal processing device comprises: A measuring cylinder, wherein an extension port is provided on a side of the top end close to the disc cylinder, an overflow port is provided on a side of the top end of the first water inlet pipe away from the central cylinder, and the extension port is located below the overflow port on the water collecting bottle in a water collecting state; a first pressure sensor, mounted on the inner wall of the measuring cylinder and control-connected to the second stepping motor; and The first drainage pipe is connected to the side wall of the bottom end of the measuring cylinder, and the maximum drainage flow rate of the first drainage pipe is 0.045 ml / min.

8. A small flow discontinuous groundwater radon concentration real-time monitoring system according to claim 1, characterized in that: The radon concentration measuring device comprises a cylindrical drying tube and a radon monitor, wherein the air inlet of the cylindrical drying tube is connected to the third air outlet, the air outlet is connected to the air inlet of the radon monitor, and the air outlet of the radon monitor is connected to the third air inlet.

9. A real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate according to claim 1, characterized in that: The cabinet is connected with a drain port at one side of the top of the water collection chamber.

10. A method for real-time monitoring of radon concentration in discontinuous groundwater with a small flow rate, based on a real-time monitoring system for radon concentration in discontinuous groundwater with a small flow rate as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1. The trumpet-shaped opening of the drainage tube is fixed directly below the exposed water sample, and the lower end of the drainage tube is placed in the water collection cavity; S2. The water sample flows through the water valve to the first water inlet pipe of the water collecting bottle in the water collecting state, and is stored in the water collecting bottle; at this time, the first air outlet pipe, the first air inlet pipe and the fourth water discharge pipe on the water collecting bottle do not form a passage with the central cylinder, the gas in the water collecting bottle is discharged through the exhaust mechanism, and the water level in the bottle continues to rise; S3. When the water level in the water collecting bottle in step S2 reaches the set value, the disc cylinder is driven to rotate 90 degrees, the water collecting bottle enters the measuring state, the first air outlet pipe is connected with the third air outlet pipe, the first air inlet pipe is connected with the third air inlet pipe, the radon gas escaped from the water collecting bottle enters the radon concentration measuring device for radon concentration detection, and the gas after the detection is completed flows back to the water collecting bottle through the third air inlet pipe and the first air inlet pipe; S4. When the radon concentration detection in the water collection bottle in step S3 is completed, the disc cylinder is driven to continue to rotate 90° in the same direction, the water collection bottle enters the drainage state, and the fourth drain pipe is connected to the third drain pipe, and the water level in the bottle continues to drop; S5. Continue to drive the disc cylinder to rotate 90° in the same direction each time, so that each water collecting bottle on the disc cylinder undergoes steps S2 to S4 in sequence, thereby achieving real-time monitoring of radon concentration in small-flow discontinuous water samples.

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