Soil heavy metal sample collection and in-situ detection analysis system and method thereof

Abstract

The invention discloses a soil heavy metal sample collection and in-situ detection analysis system and method, and the system comprises an in-situ sampling device which comprises a driving mechanism and a mechanical arm, the driving mechanism and the mechanical arm are installed at a sampling point on the ground, the driving mechanism is provided with a sampling drill bit, and the mechanical arm is provided with a sampling pipe; a screening device; the weighing device is arranged below the discharging opening of the screening device, and the weighing device is provided with a soil moisture measuring device; the stirring device is connected with a water conveying pipe, and the water conveying pipe is provided with a flowmeter; the mold is mounted at the discharge port of the stirring device; an X-ray analysis device; the controller is in signal connection with the driving device, the mechanical arm, the screening device, the first conveying device, the weighing device, the sensor, the stirring device, the water conveying pipe, the flow meter, the pressurizing device, the third conveying device and the X-ray analysis device. The invention solves the problem that the existing soil heavy metal detection method is tedious in sample treatment.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of soil heavy metal detection devices, in particular to a soil heavy metal sample collection and in-situ detection and analysis system and method thereof. BACKGROUND

[0002] Soil is an important basis for human survival and provides food sources and living space for human survival and development. At the same time, soil has the function of water storage and water retention, and can regulate surface runoff. Therefore, the health of soil directly affects the survival and development of human beings. However, with the increasing intensity of human activities and the development of industry and agriculture, a large amount of pollutants are generated in the process, which migrate to the soil through different channels and cause soil pollution. These pollutants include organic pollutants, metal pollutants, and non-metal pollutants. Heavy metal pollutants can migrate greatly in soil and plants due to their easy migration characteristics. Soil heavy metal pollution can cause the content of heavy metals in soil to exceed the standard. With the migration of heavy metals, heavy metals can accumulate in plants, thereby affecting human health. At the same time, soil heavy metal pollution can migrate to water sources, causing water source heavy metal pollution. Some pollutants in the soil enter the air through dust, which is harmful to human health. Therefore, soil heavy metal pollution has attracted much attention. Analyzing the content of heavy metals in soil is an important means to understand soil pollution. Current methods for analyzing heavy metals in soil include atomic fluorescence method (AFS), atomic absorption method (AAS), inductively coupled plasma mass spectrometry (ICP / MS), inductively coupled plasma method (ICP), X-ray fluorescence spectrometer (XRF) method, and flame spectrophotometer method. Before testing the sample, the sample needs to be collected from the field, transported to the laboratory, dried, ground, sieved, digested with multiple acids, and then analyzed. These methods have complex sample pretreatment and consume a large amount of acid during the digestion process, which is harmful to the human body and the environment. Although the XRF method does not require sample digestion, it is often used for on-site rapid screening and semi-quantitative analysis of heavy metals in soil. For accurate quantification, the sample needs to be dried and then pressed into a tablet, which is a tedious sample analysis process. SUMMARY

[0003] To overcome the defects of the prior art, a soil heavy metal sample collection and in-situ detection and analysis system and method thereof are provided to solve the problem of complex sample processing in the existing soil heavy metal detection method.

[0004] To achieve the above-mentioned purpose, a soil heavy metal sample collection and in-situ detection and analysis system is provided, which comprises: The in-situ sampling device comprises a driving mechanism and a mechanical arm, the driving mechanism and the mechanical arm are installed at a sampling point on the ground, the driving mechanism is provided with a sampling drill bit for drilling into the ground, and the mechanical arm is provided with a sampling tube for collecting soil to be tested in the sampling drill bit; A screening device is arranged between the mechanical arm and the screening device, and a first conveying device is arranged between the mechanical arm and the screening device, and the first conveying device is used for inputting the soil to be tested into the screening device. A weighing device is arranged below the discharge port of the screening device, and the weighing device is used for weighing the screened soil sample. A soil moisture measuring device is arranged in the weighing device, and the soil moisture measuring device is used for measuring the water content of the soil. A second conveying device is arranged on the weighing device, and the second conveying device is used for inputting the weighed soil to be tested into the stirring device. A mold is arranged at the discharge port of the stirring device, and the mold is provided with a pressing device for extruding the soil to be tested in the mold to form a sample block. An X-ray analysis device is arranged on the mold, and a third conveying device is arranged on the mold, and the third conveying device is used for conveying the sample block into a sample cell of the X-ray analysis device. A controller is signal-connected to the driving device, the mechanical arm, the screening device, the first conveying device, the weighing device, the sensor, the stirring device, the water conveying pipe, the flow meter, the pressing device, the third conveying device and the X-ray analysis device.

[0005] Further, the sampling tube has a closed upper end and an open lower end, a push rod is slidably arranged in the open lower end, a length-adjustable driving member is connected between the push rod and the closed upper end, the lower end of the push rod extends to the outside of the open lower end and is magnetically adsorbed to a supporting plate, the supporting plate is connected to a containing cone through a hanging plate, and after the length of the driving member is contracted, the open lower end is pressed against the supporting plate, so that the supporting plate is separated from the push rod.

[0006] Further, the sampling drill bit comprises: A drill bit body in the shape of an inverted circular truncated cone, and a vertical hole is formed in the drill bit body; A sleeve coaxially connected to the upper end of the drill bit body, and the hole is communicated with the sleeve.

[0007] Further, the discharge port is connected to the mold through an auger conveying device.

[0008] The present application provides a soil heavy metal sample collection and in-situ detection and analysis system and a soil heavy metal sample collection and in-situ detection and analysis method. The controller activates the in-situ sampling device, the drive mechanism drives the sampling drill bit to drill into the sampling point on the ground, and the robotic arm drives the sampling tube to collect the soil to be tested inside the sampling drill bit; The controller activates the first conveying device to input the soil to be tested into the screening device; The controller activates the screening device, which screens the soil to be tested. The screened soil then falls into the weighing device through the discharge port of the screening device. The weighing device collects the weight of the soil to be tested after sieving and feeds the weighed soil to be tested into the mixing device through the second conveying device. At the same time, the sensor collects the moisture content of the soil to be tested after sieving. The controller acquires the weight and moisture content of the soil to be tested, and calculates the amount of water to be added based on the preset soil moisture content and the moisture content of the soil to be tested after sieving. The controller opens the water supply pipe to allow the water supply pipe to add the specified amount of water to the stirring device; The controller activates the mixing device to mix the soil to be tested evenly and discharges it into the mold through the discharge port. The controller activates the pressurization device to compress the soil to be tested inside the mold to form a sample block; The controller activates the third conveying device to transport the sample block into the sample cell of the X-ray analysis device; The controller activates the X-ray analysis device, which detects the heavy metal content in the sample block.

[0009] Furthermore, the preset soil moisture content is 30%.

[0010] The beneficial effect of this invention lies in the fact that the soil heavy metal sample collection and in-situ detection and analysis system of this invention collects soil samples at a depth of more than 20 meters underground at the sampling point using a sampling drill bit and sampling tube. Traditional soil sampling first requires drilling to remove the original soil from underground to the surface, then cutting open the sample tube, sampling, sieving, grinding, and finally analyzing the sample. This process requires 6 to 8 people. Compared to traditional analytical methods, the soil heavy metal sample collection and in-situ detection and analysis system of this invention, through integrated design, combines sampling, sieving, weighing, sample shaping, and analysis into one in-situ analysis and detection, requiring only 3 people to complete the above work. Therefore, it can save more than 50% of labor costs. Attached Figure Description

[0011] Other features, objects, and advantages of this application will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of the soil heavy metal sample collection and in-situ detection and analysis system according to an embodiment of the present invention.

[0012] Figure 2 This is a schematic diagram of the sampling tube according to an embodiment of the present invention.

[0013] Figure 3 for Figure 2 The sectional view at point AA.

[0014] Figure 4 This is a modular schematic diagram of the soil heavy metal sample collection and in-situ detection and analysis system according to an embodiment of the present invention.

[0015] Figure label: Drive mechanism 11, robotic arm 12, sampling drill bit 13, drill bit body 131, casing 132, sampling tube 14, push rod 141, drive component 142, support plate 143, accommodating cone 144, bolt 145, lifting plate 146; Screening device 2, first conveying device 21; Weighing device 3, sensor 31, second conveying device 32; 4. Mixing device; 41. Water supply pipe; 42. Flow meter; 43. Screw conveyor device; Mold 5, pressurizing device 51; X-ray analysis device 6, third conveying device 61; Controller 7; Sample block 8. Detailed Implementation

[0016] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0017] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0018] Reference Figures 1 to 4 As shown, the present invention provides a system for collecting and in-situ detecting heavy metal samples in soil, including: an in-situ sampling device, a sieving device 2, a weighing device 3, a stirring device 4, a mold 5, an X-ray analysis device 6, and a controller 7.

[0019] The in-situ sampling device includes a drive mechanism 11 and a robotic arm 12. The drive mechanism 11 and the robotic arm 12 are installed at the sampling point on the ground. The drive mechanism 11 is equipped with a sampling drill bit 13. The sampling drill bit 13 is used to drill into the ground. A sampling tube 14 is installed on the robotic arm 12 to collect the soil sample to be tested from inside the sampling drill bit 13.

[0020] See Figure 1 The sampling drill bit 13 includes a drill bit body 131 and a casing 132.

[0021] The drill bit body 131 is generally shaped like an inverted frustum. A vertically arranged channel is formed within the drill bit body 131. A casing 132 is coaxially connected to the upper end of the drill bit body 131. The channel communicates with the casing 132.

[0022] The drive mechanism uses a hydraulic cylinder. The drive mechanism is mounted on the ground via a bracket. It is vertically positioned above the sampling point. The sampling drill bit is mounted on the telescopic end of the hydraulic cylinder. After the hydraulic cylinder extends, it presses the sampling drill bit into the soil, and the soil enters the casing through the channel.

[0023] See Figure 2 and Figure 3 The sampling tube 14 has a closed upper end and an open lower end. A push rod 141 is slidably mounted inside the open lower end. A drive member 142 is connected between the push rod 141 and the closed upper end. The length of the drive member 142 is adjustable. In some embodiments, the drive member 142 is an electro-hydraulic push rod. The lower end of the push rod 141 extends outside the lower end of the opening. A support plate 143 is magnetically attracted to the lower end of the push rod. In this embodiment, the support plate is a magnetic metal plate. A magnet is mounted on the lower end of the push rod. The magnet is magnetically attracted to the support plate. A receiving cone 144 is connected to the support plate 143 via a hanging plate 146. The opening of the receiving cone faces upward. The hanging plate is connected to the opening of the receiving cone. After the drive mechanism extends to drill the sampling drill bit into the sampling point on the ground, the robotic arm presses the sampling tube down into the casing still underground. At this time, because the receiving cone is narrower at the bottom and wider at the top, the receiving cone can enter the casing. After the cone reaches the preset depth, the robotic arm extracts the sample tube, at which point the soil inside the casing is hooked in. As the robotic arm lifts the sample tube to the ground and the length of the drive unit 142 retracts, the push rod is lifted, and the lower end of the sample tube opening presses against the support plate 143, causing the support plate 143 to separate from the push rod 141.

[0024] In this embodiment, a first conveying device 21 for inputting the soil to be tested into the screening device 2 is provided between the robotic arm 12 and the screening device 2. After the support plate separates from the push rod, the receiving cone falls onto the first conveying device. The first conveying device is a belt conveyor. The receiving cone falls onto the input end of the first conveying device and is input into the screening device via the output end of the first conveying device. The screening device is equipped with a vibrator, which uses vibration to remove the soil to be tested from the receiving cone and screen it. Through screening, soil particles larger than 20 mesh and other impurities will remain above the screen of the screening device, while soil particles smaller than 20 mesh will flow into the next process for weighing.

[0025] The weighing device 3 is located below the discharge port of the screening device 2. The weighing device is used to weigh the screened soil sample.

[0026] A soil moisture measuring device is installed inside the weighing device. The soil moisture measuring device is used to measure the moisture content of the soil. In this embodiment, the soil moisture measuring device is sensor 31. Sensor 31 is used to collect the moisture content of the soil to be tested after sieving.

[0027] A second conveying device 32 is installed on the weighing device 3. The second conveying device 32 is used to input the weighed soil to be tested into the mixing device 4. The second conveying device can be a robotic arm. In some embodiments, the weighing device is an electronic scale. A push plate is installed on the tray of the electronic scale via an electro-hydraulic push rod. After weighing, the electro-hydraulic push rod on the tray extends, and the push plate pushes the soil to be tested on the tray into the mixing device. The mixing device 4 is connected to a water supply pipe 41. A flow meter 42 is installed on the water supply pipe 41.

[0028] In this embodiment, the preset moisture content of the soil to be tested is 30%. When the soil moisture content collected by the sensor is lower than 30%, the amount of water to be added is calculated based on the moisture content collected by the sensor and the weight of the soil to be tested. The water supply pipe then inputs the required amount of water into the mixing device. The mixing device mixes the soil to be tested with the water evenly. The mold 5 is installed at the discharge port of the mixing device 4. The evenly mixed soil to be tested is discharged into the mold. A pressure device 51 is installed on the mold 5. The pressure device 51 is used to compress the soil to be tested inside the mold 5 to form a sample block 8, making the surface of the sample block smooth for subsequent testing.

[0029] In a preferred embodiment, the discharge port is connected to the mold 5 via an auger conveyor 43. The well-mixed soil to be tested enters the auger conveyor and is discharged into the mold under the compression of the auger.

[0030] In this embodiment, a third conveying device 61 is installed on the mold 5. The third conveying device 61 is used to transport the sample block 8 into the sample cell of the X-ray analysis device 6. In some embodiments, the third conveying device 61 is a belt conveyor or a robotic arm. In the X-ray analysis device, under the irradiation of X-rays, the heavy metal atoms in the sample block are excited, generating characteristic photons. These characteristic photons pass through a grating, which separates the mixed photons of different wavelengths. The characteristic photons are then received by the photon receiver in the X-ray analysis device, amplified, and then processed by the data processing system. The X-ray analysis device analyzes the content of the sample according to different slope lengths and intensities.

[0031] The X-ray analysis device is an X-ray fluorescence spectrometer.

[0032] The controller 7 is connected to the drive device, robotic arm 12, screening device 2, first conveying device 21, weighing device 3, sensor 31, stirring device 4, water pipe 41, flow meter 42, pressurizing device 51, third conveying device 61 and X-ray analysis device 6.

[0033] In this embodiment, the controller links and controls the drive device, robotic arm 12, screening device 2, first conveying device 21, weighing device 3, sensor 31, stirring device 4, water pipe 41, flow meter 42, pressurizing device 51, third conveying device 61 and X-ray analysis device 6.

[0034] Before X-ray analysis, the X-ray analyzer needs to be calibrated. In this embodiment, a certified heavy metal standard material (soil) is used and placed in a weighing device. Since the standard material is dry, its moisture content is not measured at this stage. Based on the weight of the standard material, the controller calculates how many liters of water should be added to the soil standard material when its moisture content is 30%. The pump on the delivery pipe then starts, adding a certain amount of water to the soil standard material in the mixing device, bringing its moisture content to 35%. The standard material is then thoroughly mixed in the mixing device and conveyed through a auger into a mold for extrusion, forming a smooth and compact standard sample block. The standard sample block then enters the sample cell for content determination. The X-ray analyzer automatically calibrates based on the standard material content. The X-ray analyzer is designed with three standard material calibration values. Calibration for different concentrations of standard material is completed following the above steps.

[0035] This invention provides a method for collecting and analyzing heavy metal samples in soil using a soil heavy metal sample collection and in-situ detection and analysis system, comprising the following steps: S1, Controller 7 activates the in-situ sampling device, Drive mechanism 11 drives sampling drill bit 13 to drill into the sampling point on the ground, and robotic arm 12 drives sampling tube 14 to collect the soil to be tested inside sampling drill bit 13.

[0036] S2, Controller 7 activates the first conveying device 21 to input the soil to be tested into the screening device 2.

[0037] S3, Controller 7 starts the screening device 2, the screening device 2 screens the soil to be tested, and the screened soil to be tested falls into the weighing device 3 through the discharge port of the screening device 2.

[0038] S4. The weighing device 3 collects the weight of the soil to be tested after sieving and inputs the weighed soil to be tested into the mixing device 4 through the second conveying device. At the same time, the sensor 31 collects the moisture content of the soil to be tested after sieving.

[0039] S5 and controller 7 acquire the weight and moisture content of the soil to be tested, and calculate the amount of water to be added based on the preset soil moisture content and the moisture content of the soil to be tested after sieving.

[0040] The preset soil moisture content is 30%.

[0041] S6, Controller 7 opens water supply pipe 41 so that water supply pipe 41 adds the required amount of water to stirring device 4.

[0042] S7, Controller 7 turns on the mixing device 4 to mix the soil to be tested evenly and discharge it into the mold 5 through the discharge port.

[0043] S8, Controller 7 activates the pressurization device 51 to compress the soil to be tested in the mold 5 to form a sample block 8.

[0044] S9, Controller 7 activates the third conveying device 61 to convey the sample block 8 into the sample cell of the X-ray analysis device 6.

[0045] S10, Controller 7 turns on X-ray analysis device 6, X-ray analysis device 6 detects the heavy metal content in sample block 8.

[0046] In this embodiment, after the analysis is complete, the controller starts the pump on the water supply pipe and another water supply pipe to rinse the stirring device and sample cell. After rinsing, the waste liquid is discharged into the waste liquid tank.

[0047] The soil heavy metal sampling and in-situ detection and analysis system of this invention collects soil samples at a depth of more than 20 meters at the sampling point using a sampling drill and sampling tube. Traditional soil sampling requires drilling to extract the original soil from underground to the surface, then cutting open the sample tube for sampling, sieving, grinding, and analysis. This process requires 6 to 8 people. Compared to traditional methods, the soil heavy metal sampling and in-situ detection and analysis system of this invention, through integrated design, combines sampling, sieving, weighing, sample shaping, and analysis into one in-situ process, requiring only 3 people to complete the work, thus saving more than 50% of labor costs.

[0048] The sampling tube of the soil heavy metal sample collection and in-situ detection and analysis system of the present invention adopts an inverted hook design, which makes the container cone easy to disassemble and assemble, and convenient for sampling. In order to ensure that the sample is not contaminated by the external environment of the system, all parts of the system that come into contact with the soil sample are designed with PVC lining to protect the heavy metals in the soil sample from external contamination.

[0049] The soil heavy metal sample collection and in-situ detection and analysis system of this invention calibrates the soil standard material under a moisture content of 35%, avoiding the influence of soil moisture content on the accuracy of the analysis. To ensure that the soil sample has good plasticity, resulting in a smooth surface and a compact structure, the system uses sample weighing and soil moisture content collection to mold the soil under a 35% moisture content condition, ensuring the accuracy and reproducibility of the sample measurement results.

[0050] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A system for collecting and in-situ detecting heavy metal samples in soil, characterized in that, include: An in-situ sampling device includes a drive mechanism and a robotic arm. The drive mechanism and the robotic arm are installed at a sampling point on the ground. The drive mechanism is equipped with a sampling drill bit for drilling into the ground, and the robotic arm is equipped with a sampling tube to collect the soil to be tested inside the sampling drill bit. A screening device, wherein a first conveying device for inputting the soil to be tested into the screening device is provided between the robotic arm and the screening device; A weighing device is installed below the discharge port of the screening device for weighing the screened soil sample. A soil moisture measuring device is installed inside the weighing device and is used to measure the soil moisture content. A mixing device, wherein the weighing device is equipped with a second conveying device for inputting the weighed soil to be tested into the mixing device, the mixing device is connected to a water supply pipe, and the water supply pipe is equipped with a flow meter; A mold is installed at the discharge port of the mixing device, and a pressure device is installed on the mold for squeezing the soil to be tested inside the mold to form a sample block; An X-ray analysis apparatus, wherein a third conveying device is installed on the mold for conveying the sample block into the sample cell of the X-ray analysis apparatus; The controller is connected to the drive device, the robotic arm, the screening device, the first conveying device, the weighing device, the sensor, the stirring device, the water supply pipe, the flow meter, the pressurizing device, the third conveying device, and the X-ray analysis device.

2. The soil heavy metal sample collection and in-situ detection and analysis system according to claim 1, characterized in that, The sampling tube has a closed upper end and an open lower end. A push rod is slidably disposed inside the open lower end. An adjustable-length drive is connected between the push rod and the closed upper end. The lower end of the push rod extends to the outside of the open lower end and is magnetically attached to a support plate. The support plate is connected to a accommodating cone via a hanging plate. After the length of the drive is retracted, the open lower end presses against the support plate, causing the support plate to separate from the push rod.

3. The soil heavy metal sample collection and in-situ detection and analysis system according to claim 1, characterized in that, The sampling drill bit includes: The drill bit body is in the shape of an inverted frustum, and vertically arranged channels are formed within the drill bit body. The casing is coaxially connected to the upper end of the drill bit body, and the channel communicates with the casing.

4. The soil heavy metal sample collection and in-situ detection and analysis system according to claim 1, characterized in that, The discharge port is connected to the mold via an auger conveyor.

5. A method for collecting and analyzing heavy metal samples in soil using the soil heavy metal sample collection and in-situ detection and analysis system as described in any one of claims 1 to 4, characterized in that, Includes the following steps: The controller activates the in-situ sampling device, the drive mechanism drives the sampling drill bit to drill into the sampling point on the ground, and the robotic arm drives the sampling tube to collect the soil to be tested inside the sampling drill bit; The controller activates the first conveying device to input the soil to be tested into the screening device; The controller activates the screening device, which screens the soil to be tested. The screened soil then falls into the weighing device through the discharge port of the screening device. The weighing device collects the weight of the soil to be tested after sieving and feeds the weighed soil to be tested into the mixing device through the second conveying device. At the same time, the sensor collects the moisture content of the soil to be tested after sieving. The controller acquires the weight and moisture content of the soil to be tested, and calculates the amount of water to be added based on the preset soil moisture content and the moisture content of the soil to be tested after sieving. The controller opens the water supply pipe to allow the water supply pipe to add the specified amount of water to the stirring device; The controller activates the mixing device to mix the soil to be tested evenly and discharges it into the mold through the discharge port. The controller activates the pressurization device to compress the soil to be tested inside the mold to form a sample block; The controller activates the third conveying device to transport the sample block into the sample cell of the X-ray analysis device; The controller activates the X-ray analysis device, which detects the heavy metal content in the sample block.

6. The method for collecting and in-situ detecting heavy metal samples in soil according to claim 5, characterized in that, The preset soil moisture content is 30%.

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