An in-situ monitoring device and method for VOC gases in soil

Abstract

The present invention relates to an in-situ monitoring device and method for VOC gases in soil, and relates to the technical field of treatment of soil and groundwater polluted by volatile organic compounds. The in-situ monitoring rod group includes a monitoring rod and a probe connected in sequence from top to bottom. The side wall of the monitoring rod has monitoring holes, and the side wall of the probe has air extraction holes; the monitoring holes are communicated with a monitoring pipeline, and an extraction influence range monitoring component is provided on the monitoring pipeline. The air extraction holes, a gas detection device and an air pump are sequentially communicated through an air extraction pipeline, and the outlet of the air pump is respectively communicated with an exhaust gas pipeline and a gas collection device; the control module is respectively in communication connection with the extraction influence range monitoring component, the gas detection device and the air pump. The purpose of the present invention is to conduct in-situ continuous monitoring of VOCs gases in soil, and at the same time, soil gas samples can be collected, and the gas collection device can also be connected to an external detection device to quantitatively measure the components in the soil gas. Through working condition conversion, the gas permeability test of soil layers can be carried out.

Description

Technical Field

[0001] The present invention relates to the technical field of treating polluted soil and groundwater by volatile organic compounds, and particularly relates to an in-situ monitoring device and method for VOC gases in soil. Background Art

[0002] With the continuous improvement of the degree of industrial modernization, a large number of polluted sites have been left in large and medium-sized cities, and the degree of soil and groundwater pollution has been increasingly taken seriously. VOCs (volatile organic compounds), volatile organic compounds are the most common and high-risk pollutants in polluted sites, which bring serious impacts on human health and ecological balance. Due to the high volatility and high biological toxicity of VOCs pollutants, and their long-term high-concentration accumulation in soil, once the soil is excavated and disturbed, it is extremely easy to generate many environmental risks and even accidents. In the investigation of VOCs (volatile organic compounds) polluted sites, the importance of soil gas has been increasingly taken seriously.

[0003] The soil gas concentration is an important indicator indicating the degree of soil VOCs pollution and environmental risks. Soil gas monitoring is easier to expose VOCs pollution in the strata than soil monitoring. Inhaling polluted gas is the main human exposure route of VOCs in polluted plots, and soil gas monitoring data is an important basis for VOCs risk assessment. Soil gas sampling and monitoring can better evaluate the degree of VOCs pollution in soil.

[0004] During the in-situ remediation process of VOCs polluted sites, by monitoring the concentration of VOCs in soil gas, the remediation effect can be evaluated more quickly, intuitively and effectively. Due to the trailing effect of in-situ remediation of VOCs polluted soil and the disturbance of the soil caused by the development and construction within the plot, the concentration of other VOCs in the soil will change. Through in-situ monitoring of soil gas, the health impact of the concentration of VOCs in soil gas after remediation and the change trend of VOCs in soil gas can be evaluated quickly and effectively. The potential environmental risks during the subsequent development and utilization of the plot can be reduced. With the introduction of the domestic soil gas sampling technical guidelines, soil gas monitoring will be gradually popularized.

[0005] At present, the domestic monitoring of soil gas is mainly to send the in-situ sampled soil gas to the laboratory for detecting the concentration of VOCs in soil gas, and there is little in-situ continuous monitoring, with low timeliness and economic benefits. Summary of the Invention

[0006] The technical problem to be solved by the present invention is how to perform in-situ soil monitoring.

[0007] The technical solution of the present invention for solving the above technical problem is as follows: An in-situ monitoring device for VOC gases in soil includes an in-situ monitoring rod group, an extraction influence range monitoring component, a gas detection device, an air pump and a control module.

[0008] The in-situ monitoring rod group includes a monitoring rod and a probe connected in sequence from top to bottom. The side wall of the monitoring rod has monitoring holes, and the side wall of the probe has air extraction holes;

[0009] The monitoring holes are communicated with a monitoring pipeline, and the extraction influence range monitoring component is arranged on the monitoring pipeline.

[0010] The air extraction holes, the gas detection device and the air pump are communicated in sequence through an air extraction pipeline, and the outlet of the air pump is communicated with an exhaust gas pipeline;

[0011] The control module is respectively in communication connection with the extraction influence range monitoring component, the gas detection device and the air pump.

[0012] The beneficial effects of the present invention are as follows: When conducting in-situ monitoring of soil gas, after hammering or drilling, the in-situ monitoring rod group is placed at a set depth, and then the drilling hole is sealed. The air pump extracts gas from the air extraction holes, and the gas detection device detects the concentration of the substance to be detected in the extracted gas, so as to monitor the soil gas at the set depth. The monitoring holes are at a certain distance above the air extraction holes. The extraction influence range monitoring component is designed to monitor whether the gas extraction influence range exceeds the set range, and can monitor the tightness of the extraction monitoring well. The control module can set the gas flow rate of the air pump, or adjust the gas flow rate of the air pump according to the influence range monitoring data measured by the extraction influence range monitoring component.

[0013] Based on the above technical solutions, the present invention can also be improved as follows.

[0014] Further, it further includes a gas collection device, and the outlet of the air pump is respectively communicated with the exhaust gas pipeline and the gas collection device.

[0015] The beneficial effect of adopting the above further solution is that the gas collection device can store the collected gas for subsequent experimental use.

[0016] Further, it further includes a first solenoid valve, a second solenoid valve, a third solenoid valve and a fourth solenoid valve respectively in communication connection with the control module.

[0017] The air extraction holes, the first end of the first solenoid valve, the second end of the first solenoid valve, the gas detection device, the first end of the second solenoid valve, the second end of the second solenoid valve, the air pump, the first end of the third solenoid valve, the third end of the third solenoid valve, the first end of the fourth solenoid valve, the third end of the fourth solenoid valve and the third end of the first solenoid valve are communicated in sequence.

[0018] The third end of the second solenoid valve is communicated with the intake pipe, the second end of the third solenoid valve is communicated with the tail gas pipe, and the second end of the fourth solenoid valve is communicated with the gas collection device.

[0019] The beneficial effect of adopting the above further solution is that when the control module controls the air extraction hole, the gas detection device, the air pump and the tail gas pipe to be communicated in sequence, it is the gas monitoring mode. The air pump extracts gas from the air extraction hole, and the gas detection device detects the concentration of the substance to be detected in the extracted gas, so as to monitor the soil gas at a set depth.

[0020] When the control module controls the air extraction hole, the gas detection device, the air pump and the gas collection device to be communicated in sequence, it is the sample collection mode. The air pump extracts gas from the air extraction hole, the gas detection device detects the concentration of the substance to be detected in the extracted gas, and stores the gas in the gas collection device, or the gas detection device does not detect, and the gas is directly stored in the gas collection device.

[0021] When the control module controls the intake pipe, the air pump and the air extraction hole to be communicated in sequence, it is the soil gas permeability test mode. At this time, the air pump blows air into the air extraction hole, and the soil gas permeability can be judged according to the gas flow and pressure on the air extraction pipe.

[0022] Further, a gas treatment component and an air extraction pipe monitoring component are sequentially arranged on the air extraction pipe between the air extraction hole and the gas detection device, and the air extraction pipe monitoring component is communicatively connected with the control module.

[0023] The beneficial effect of adopting the above further solution is that the gas treatment component treats the gas, such as drying and filtering, which is convenient for subsequent gas component detection. The air extraction pipe monitoring component is used to detect the pressure and flow of the air extraction pipe.

[0024] Further, the extraction influence range monitoring component includes a first pressure gauge and a first flow meter connected to the monitoring pipe;

[0025] The gas treatment component includes a filter and a dryer, and the filter and the dryer are connected in series on the air extraction pipe between the air extraction hole and the gas detection device;

[0026] The air extraction pipe monitoring component includes a second pressure gauge and a second flow meter, and the second pressure gauge and the second flow meter are respectively communicated with the air extraction pipe between the dryer and the gas detection device;

[0027] An air extraction filter is arranged inside the end of the air extraction pipe communicated with the air extraction hole.

[0028] The beneficial effects of adopting the above further solution are as follows: The first pressure gauge and the first flow meter are used to monitor the gas pressure and flow rate at the monitoring hole to determine whether the gas flow rate at the air extraction hole is appropriate. If the gas pressure and flow rate at the monitoring hole are not zero, the gas flow rate of the air pump needs to be reduced.

[0029] The filter and the dryer are designed to filter and dry the extracted gas to remove moisture and particulate matter in the gas.

[0030] The second pressure gauge and the second flow meter detect the gas pressure and flow rate data of the air extraction pipeline and transmit them to the control module in real time. According to specific requirements, the gas extraction pressure and flow rate are adjusted by adjusting the gas flow rate of the air pump.

[0031] The air extraction filter reduces the entry of soil or debris into the pipeline for preliminary filtration, and then the filter is used for filtration.

[0032] Furthermore, the outlet of the tail gas pipeline is also connected to a tail gas treatment device; the in-situ monitoring rod group further includes a drill rod, and the drill rod, the monitoring rod, and the probe are connected in sequence from top to bottom.

[0033] The beneficial effects of adopting the above further solution are as follows: The tail gas treatment device treats the discharged gas to make the gas meet the emission standards. The drill rod is provided to facilitate the monitoring rod and the probe to penetrate deep into the soil.

[0034] Furthermore, it further includes a display and storage module, and the control module is communicatively connected to the display and storage module.

[0035] The beneficial effects of adopting the above further solution are as follows: The display and storage module can display and store the system operation parameters, mainly including the date, time, gas pressure and flow rate in the pipeline, the detection results of soil gas, etc.

[0036] The present invention also provides a method for in-situ monitoring of VOC gas in soil. Using the in-situ monitoring equipment for VOC gas in soil, it includes the following steps:

[0037] The control module switches the in-situ monitoring equipment for VOC gas in soil to a preset mode.

[0038] In the preset mode, the control module adjusts the gas flow rate of the air pump according to the influence range monitoring data measured by the extraction influence range monitoring component, or sets the gas flow rate of the air pump according to experimental requirements, and the control module obtains the gas parameter data measured by the gas detection device.

[0039] The beneficial effects are as follows: The in-situ monitoring method for VOC gases in soil realizes real-time monitoring of VOC gases in soil, and the control module can adjust the gas flow rate of the air pump according to the monitoring data of the influence range, with high test accuracy and high automation degree.

[0040] Furthermore, the outlet of the air pump is respectively connected to the tail gas pipeline and the gas collection device, and the preset modes include a gas monitoring mode and a sample collection mode;

[0041] In the gas monitoring mode, the control module controls the outlet of the air pump to switch to be connected to the tail gas pipeline, and the control module controls the air extraction hole, the gas detection device, the air pump, and the tail gas pipeline to be connected in sequence;

[0042] In the sample collection mode, the control module controls the outlet of the air pump to switch to be connected to the gas collection device, and the control module controls the air extraction hole, the gas detection device, the air pump, and the gas collection device to be connected in sequence.

[0043] The beneficial effect of adopting the above further solution is that the switching between the gas monitoring mode and the sample collection mode can be realized, meeting the needs of multiple users.

[0044] Furthermore, an intake pipe is connected to the air extraction pipeline between the gas detection device and the air pump, and an air extraction pipe monitoring component communicatively connected to the control module is also provided on the air extraction pipeline between the air extraction hole and the gas detection device. The control module can also switch the in-situ monitoring device for VOC gases in soil to the soil gas permeability test mode;

[0045] In the soil gas permeability test mode, the control module controls the intake pipe, the air pump, and the air extraction hole to be connected in sequence. The control module adjusts the gas flow rate of the air pump according to the influence range monitoring data measured by the extraction influence range monitoring component, or sets the gas flow rate of the air pump according to experimental requirements, and the control module obtains the air extraction pipe monitoring data measured by the air extraction pipe monitoring component.

[0046] The beneficial effect of adopting the above further solution is that the switching between the gas monitoring mode, the sample collection mode, and the soil gas permeability test mode can be realized, achieving multiple functions.

[0047] The present invention aims to conduct in-situ continuous monitoring of VOCs gases in soil, and at the same time, can collect soil gas samples. The gas collection device can also be connected to an external detection device to quantitatively measure the components in the soil gas. Through working condition conversion, the gas permeability test of the soil layer can be carried out. Description of the Drawings

[0048] Figure 1This is the schematic diagram of the in-situ monitoring equipment for VOC gases in soil of the present invention.

[0049] In the attached drawings, the list of components represented by each reference numeral is as follows:

[0050] 1. Monitoring rod; 101. Monitoring hole; 2. Probe; 201. Air extraction hole; 3. Gas detection device; 4. Air pump; 5. Gas collection device;

[0051] 6. First solenoid valve; 6a. First end of valve one; 6b. Second end of valve one; 6c. Third end of valve one;

[0052] 7. Second solenoid valve; 7a. First end of valve two; 7b. Second end of valve two; 7c. Third end of valve two;

[0053] 8. Third solenoid valve; 8a. First end of valve three; 8b. Second end of valve three; 8c. Third end of valve three;

[0054] 9. Fourth solenoid valve; 9a. First end of valve four; 9b. Second end of valve four; 9c. Third end of valve four;

[0055] 10. Intake pipe; 11. First pressure gauge; 12. First flow meter; 13. Filter; 14. Dryer; 15. Second pressure gauge; 16. Second flow meter; 17. Air extraction filter; 18. Tail gas treatment device; 19. Control module; 20. Display and storage module; 21. Drill pipe. Detailed implementation manners

[0056] The principles and features of the present invention are described below. The examples given are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0057] As Figure 1 shown, this embodiment provides an in-situ monitoring equipment for VOC gases in soil, including an in-situ monitoring rod group, an extraction influence range monitoring component, a gas detection device 3, an air pump 4 and a control module 19.

[0058] The in-situ monitoring rod group includes a monitoring rod 1 and a probe 2 connected in sequence from top to bottom. The side wall of the monitoring rod 1 has a monitoring hole 101, and the side wall of the probe 2 has an air extraction hole 201.

[0059] The monitoring hole 101 is communicated with a monitoring pipeline, and the extraction influence range monitoring component is arranged on the monitoring pipeline.

[0060] The air extraction hole 201, the gas detection device 3 and the air pump 4 are sequentially communicated through an air extraction pipeline, and the outlet of the air pump 4 is communicated with a tail gas pipeline.

[0061] The control module 19 is respectively communicatively connected to the extraction influence range monitoring component, the gas detection device 3, and the air pump 4.

[0062] During in-situ soil gas monitoring, a soil VOC gas monitoring hole is formed by hammering or drilling. The in-situ monitoring rod group is placed at a set depth in the soil VOC gas monitoring hole, and then the drilling hole is sealed. The air pump 4 extracts gas from the extraction hole 201, and the gas detection device 3 detects the concentration of the substance to be detected in the extracted gas to monitor the soil gas at the set depth. The monitoring hole 101 is at a certain distance above the extraction hole 201. The extraction influence range monitoring component is designed to monitor whether the extraction influence range of the gas exceeds the set range and can monitor the tightness of the soil VOC gas monitoring hole. The control module 19 can set the gas flow rate of the air pump 4 or adjust the gas flow rate of the air pump 4 according to the influence range monitoring data measured by the extraction influence range monitoring component.

[0063] Specifically, the gas detection device 3 detects the concentration of the substance to be detected in the extracted gas. The substance to be detected specifically includes: VOCs in the extracted gas, and may also include oxygen, methane, carbon dioxide, etc.

[0064] Preferably, the probe 2 is of a hollow rod structure, with a conical head at the lower end. The extraction hole 201 is provided 10 - 30 cm above the conical head, and the upper end of the probe 2 has a threaded section for connection.

[0065] Preferably, the monitoring hole 101 is 50 cm - 200 cm above the extraction hole 201, and the lower end of the monitoring rod 1 is threadedly connected to the upper end of the probe 2. More preferably, the monitoring hole 101 is 100 cm above the extraction hole 201. Further optionally, at least one intermediate monitoring rod section can be added between the monitoring rod 1 and the probe 2. The monitoring rod 1, the intermediate monitoring rod section, and the probe 2 are connected in sequence, and by changing the length or number of the intermediate monitoring rod sections, the distance between the monitoring hole 101 and the extraction hole 201 can be adjusted.

[0066] Specifically, the middle parts of both the monitoring rod 1 and the probe 2 are hollow. The lower end of the monitoring pipeline passes through the monitoring rod 1 and is connected and communicated with the monitoring hole 101. The lower end of the air extraction pipeline passes through the monitoring rod 1 and the probe 2. The intermediate monitoring rod section is also a hollow rod body for the pipeline to pass through.

[0067] Preferably, the gas detection device 3 includes a PID gas detector, and the PID gas detector is communicatively connected to the control module 19. The control module can control the detection time period of the PID gas detector.

[0068] Based on any of the above solutions, a gas collection device 5 is further included. The outlet of the air pump 4 is respectively communicated with the tail gas pipeline and the gas collection device 5.

[0069] The gas collection device 5 can store the collected gas for subsequent experiments.

[0070] Based on any of the above solutions, it further includes a first solenoid valve 6, a second solenoid valve 7, a third solenoid valve 8, and a fourth solenoid valve 9 that are respectively communicatively connected to the control module 19.

[0071] The air extraction hole 201, the first end of the first solenoid valve 6, the second end of the first solenoid valve 6, the gas detection device 3, the first end of the second solenoid valve 7, the second end of the second solenoid valve 7, the air pump 4, the first end of the third solenoid valve 8, the third end of the third solenoid valve 8, the first end of the fourth solenoid valve 9, the third end of the fourth solenoid valve 9, and the third end of the first solenoid valve 6 are sequentially connected.

[0072] The third end of the second solenoid valve 7 is connected to the air inlet pipe 10, the second end of the third solenoid valve 8 is connected to the tail gas pipeline, and the second end of the fourth solenoid valve 9 is connected to the gas collection device 5.

[0073] Specifically, the first solenoid valve 6, the second solenoid valve 7, the third solenoid valve 8, and the fourth solenoid valve 9 are all three-way valves.

[0074] Among them, the first end of the first solenoid valve 6 is denoted as the first end of valve one 6a, the second end of the first solenoid valve 6 is denoted as the second end of valve one 6b, and the third end of the first solenoid valve 6 is denoted as the third end of valve one 6c.

[0075] Among them, the first end of the second solenoid valve 7 is denoted as the first end of valve two 7a, the second end of the second solenoid valve 7 is denoted as the second end of valve two 7b, and the third end of the second solenoid valve 7 is denoted as the third end of valve two 7c.

[0076] Among them, the first end of the third solenoid valve 8 is denoted as the first end of valve three 8a, the second end of the third solenoid valve 8 is denoted as the second end of valve three 8b, and the third end of the third solenoid valve 8 is denoted as the third end of valve three 8c.

[0077] Among them, the first end of the fourth solenoid valve 9 is denoted as the first end of valve four 9a, the second end of the fourth solenoid valve 9 is denoted as the second end of valve four 9b, and the third end of the fourth solenoid valve 9 is denoted as the third end of valve four 9c.

[0078] When the control module 19 controls the air extraction hole 201, the gas detection device 3, the air pump 4 and the tail gas pipeline to be connected in sequence, it is in the gas monitoring mode. The air pump 4 extracts gas from the air extraction hole 201, and the gas detection device 3 detects the concentration of the substance to be detected in the extracted gas, monitors the soil gas at a set depth, and then the gas is discharged from the tail gas pipeline. Specifically, in the gas monitoring mode, the air extraction hole 201, the first end 6a of valve one, the second end 6b of valve one, the gas detection device 3, the first end 7a of valve two, the second end 7b of valve two, the air pump 4, the first end 8a of valve three, the second end 8b of valve three and the tail gas pipeline are connected in sequence, and the other valve ports are closed.

[0079] When the control module 19 controls the air extraction hole 201, the gas detection device 3, the air pump 4 and the gas collection device 5 to be connected in sequence, it is in the sample collection mode. The air pump 4 extracts gas from the air extraction hole 201, and the gas detection device 3 detects the concentration of the substance to be detected in the extracted gas and stores the gas in the gas collection device 5, or the gas detection device 3 does not detect, and the gas is directly stored in the gas collection device 5. Specifically, in the sample collection mode, the air extraction hole 201, the first end 6a of valve one, the second end 6b of valve one, the gas detection device 3, the first end 7a of valve two, the second end 7b of valve two, the air pump 4, the first end 8a of valve three, the third end 8c of valve three, the first end 9a of valve four, the second end 9b of valve four and the gas collection device 5 are connected in sequence, and the other valve ports are closed.

[0080] When the control module 19 controls the air inlet pipe 10, the air pump 4 and the air extraction hole 201 to be connected in sequence, it is in the soil gas permeability test mode. At this time, the air pump 4 blows air into the air extraction hole 201, and the soil gas permeability can be judged according to the gas flow and pressure on the air extraction pipeline. Specifically, in the soil gas permeability test mode, the air inlet pipe 10, the third end 7c of valve two, the second end 7b of valve two, the air pump 4, the first end 8a of valve three, the third end 8c of valve three, the first end 9a of valve four, the third end 9c of valve four, the third end 6c of valve one, the first end 6a of valve one and the air extraction hole 201 are connected in sequence, and the other valve ports are closed.

[0081] On the basis of any of the above solutions, a gas treatment component and an air extraction pipe monitoring component are sequentially arranged on the air extraction pipeline between the air extraction hole 201 and the gas detection device 3, and the air extraction pipe monitoring component is communicatively connected with the control module 19.

[0082] The gas treatment component treats the gas, such as drying and filtering, to facilitate subsequent gas component detection. The air extraction pipe monitoring component is used to detect the pressure and flow of the air extraction pipeline, and can also be used to detect other gas parameters.

[0083] On the basis of any of the above solutions, the extraction influence range monitoring component includes a first pressure gauge 11 and a first flow meter 12 connected to the monitoring pipeline;

[0084] The gas treatment component includes a filter 13 and a dryer 14, and the filter 13 and the dryer 14 are connected in series on the air extraction pipeline between the air extraction hole 201 and the gas detection device 3;

[0085] The air extraction pipe monitoring component includes a second pressure gauge 15 and a second flow meter 16, and the second pressure gauge 15 and the second flow meter 16 are respectively communicated with the air extraction pipeline between the dryer 14 and the gas detection device 3;

[0086] An air extraction filter 17 is arranged inside one end of the air extraction pipeline communicating with the air extraction hole 201.

[0087] Among them, the first pressure gauge 11 and the first flow meter 12 are used to monitor the gas pressure and flow rate at the monitoring hole 101 to judge whether the gas flow rate of the air extraction hole 201 is appropriate. If the gas pressure and flow rate at the monitoring hole 101 are not zero, it is necessary to reduce the gas flow rate of the air pump 4.

[0088] The filter 13 and the dryer 14 are designed to filter and dry the extracted gas to remove moisture and particulate matter in the gas.

[0089] The second pressure gauge 15 and the second flow meter 16 detect the gas pressure and flow rate data of the air extraction pipeline and transmit them to the control module in real time. According to specific requirements, the gas extraction pressure and flow rate are adjusted by adjusting the gas flow rate of the air pump 4.

[0090] The air extraction filter 17 reduces the entry of soil or debris into the pipeline for preliminary filtration, and then the filter 13 conducts filtration.

[0091] On the basis of any of the above solutions, the outlet of the tail gas pipeline is also communicated with a tail gas treatment device 18; the in-situ monitoring rod group further includes a drill rod 21, and the drill rod 21, the monitoring rod 1 and the probe 2 are connected in sequence from top to bottom.

[0092] The tail gas treatment device 18 treats the discharged gas to make the gas meet the emission standards. The drill rod 21 is provided to facilitate the monitoring rod 1 and the probe 2 to penetrate deep into the soil.

[0093] The tail gas treatment device 18 can be realized by existing technologies. For example, the VOC waste gas can be treated by means such as thermal destruction method or activated carbon adsorption method.

[0094] On the basis of any of the above solutions, it further includes a display and storage module 20, and the control module 19 and the display and storage module 20 are communicatively connected.

[0095] The display and storage module 20 can display and store the system operation parameters, mainly including the date, time, pressure and flow rate of the gas in the pipeline, the detection results of the soil gas, etc.

[0096] On the basis of any of the above solutions, the specific process of inserting the in-situ monitoring rod group into the soil is as follows:

[0097] 1. After hammering or drilling, hammer the probe 2 to a relatively shallow depth.

[0098] 2. Connect the drill pipe 21, the monitoring rod 1 and the probe 2 according to the set measurement position.

[0099] 3. Then hammer the probe 2 to the set depth.

[0100] The present invention also provides an in-situ monitoring method for VOC gases in soil. Using the in-situ monitoring device for VOC gases in soil, it includes the following steps:

[0101] The control module 19 switches the in-situ monitoring device for VOC gases in soil to a preset mode.

[0102] In the preset mode, the control module 19 adjusts the gas flow rate of the air pump 4 according to the influence range monitoring data measured by the extraction influence range monitoring component, or sets the gas flow rate of the air pump 4 according to experimental requirements, and the control module 19 obtains the gas parameter data measured by the gas detection device 3.

[0103] The in-situ monitoring method for VOC gases in soil realizes the real-time monitoring of VOC gases in soil, and the control module can adjust the gas flow rate of the air pump 4 according to the influence range monitoring data, with high test accuracy and high automation degree.

[0104] Specifically, the control module 19 can also control the working time of the air pump 4.

[0105] Specifically, the influence range monitoring data includes the first pressure value measured by the first pressure gauge 11 and the first flow rate value measured by the first flow meter 12.

[0106] On the basis of any of the above solutions, the outlet of the air pump 4 is respectively communicated with the tail gas pipeline and the gas collection device 5, and the preset mode includes a gas monitoring mode and a sample collection mode;

[0107] In the gas monitoring mode, the control module 19 controls the air extraction hole 201, the gas detection device 3, the air pump 4 and the tail gas pipeline to be communicated in sequence, and the control module 19 controls the outlet of the air pump 4 to be switched to be communicated with the tail gas pipeline.

[0108] In the sample collection mode, the control module 19 controls the air extraction hole 201, the gas detection device 3, the air pump 4 and the gas collection device 5 to be connected in sequence, and the control module 19 controls the outlet of the air pump 4 to be switched to be connected to the gas collection device 5.

[0109] It can realize the switching between two modes of gas monitoring mode and sample collection mode, meeting the needs of various users.

[0110] On the basis of any of the above solutions, an intake pipe 10 is connected to the air extraction pipeline between the gas detection device 3 and the air pump 4. A suction pipe monitoring component communicatively connected to the control module 19 is also provided on the air extraction pipeline between the air extraction hole 201 and the gas detection device 3. The control module 19 can also switch the device to the soil gas permeability test mode;

[0111] In the soil gas permeability test mode, the control module 19 controls the intake pipe 10, the air pump 4 and the air extraction hole 201 to be connected in sequence. The control module 19 adjusts the gas flow rate of the air pump 4 according to the influence range monitoring data measured by the extraction influence range monitoring component, or sets the gas flow rate of the air pump 4 according to experimental requirements, and the control module 19 obtains the suction pipe monitoring data measured by the suction pipe monitoring component.

[0112] It can realize the switching among three modes of gas monitoring mode, sample collection mode and soil gas permeability test mode, realizing multiple functions.

[0113] In the gas monitoring mode, specifically:

[0114] 1. Install the in-situ monitoring rod group, and the control module 19 controls the air extraction hole 201, the gas detection device 3, the air pump 4 and the tail gas pipeline to be connected in sequence;

[0115] 2. Conduct a trial run. The control module 19 obtains the first pressure value measured by the first pressure gauge 11 and the first flow value measured by the first flow meter 12, judges whether both the first pressure value and the first flow value are zero, generates a judgment result. If the judgment result is yes, proceed to the subsequent steps. If the judgment result is no, reduce the gas flow rate of the air pump 4, or the control module 19 sets the gas flow rate of the air pump 4 according to experimental requirements;

[0116] 3. The control module 19 sets the operation time of the in-situ monitoring equipment for VOC gas in the soil;

[0117] 4. Operate the in-situ monitoring equipment for VOC gas in the soil. The control module 19 obtains the gas parameter data measured by the gas detection device 3, and records and monitors in real time the second pressure value measured by the second pressure gauge 15 and the second flow value measured by the second flow meter 16.

[0118] In the sample collection mode, specifically:

[0119] 1. Install the in-situ monitoring rod group, and the control module 19 controls the air extraction hole 201, the gas detection device 3, the air pump 4, and the gas collection device 5 to be connected in sequence;

[0120] 2. Conduct a trial run. The control module 19 obtains the first pressure value measured by the first pressure gauge 11 and the first flow value measured by the first flow meter 12, determines whether both the first pressure value and the first flow value are zero, generates a judgment result. If the judgment result is yes, proceed to the subsequent steps. If the judgment result is no, reduce the gas flow of the air pump 4, or the control module 19 sets the gas flow of the air pump 4 according to the experimental requirements;

[0121] 3. The control module 19 sets the operating time of the in-situ monitoring equipment for VOC gases in the soil;

[0122] 4. Operate the in-situ monitoring equipment for VOC gases in the soil. The control module 19 obtains the gas parameter data measured by the gas detection device 3, and simultaneously records and monitors the second pressure value measured by the second pressure gauge 15 and the second flow value measured by the second flow meter 16. The gas is stored in the gas collection device 5.

[0123] In the soil gas permeability test mode, specifically:

[0124] 1. Install the in-situ monitoring rod group, and the control module 19 controls the air inlet pipe 10, the air pump 4, and the air extraction hole 201 to be connected in sequence.

[0125] 2. Conduct a trial run. The control module 19 obtains the first pressure value measured by the first pressure gauge 11 and the first flow value measured by the first flow meter 12, determines whether both the first pressure value and the first flow value are zero, generates a judgment result. If the judgment result is yes, proceed to the subsequent steps. If the judgment result is no, reduce the gas flow of the air pump 4, or the control module 19 sets the gas flow of the air pump 4 according to the experimental requirements;

[0126] 3. The control module 19 sets the operating time of the in-situ monitoring equipment for VOC gases in the soil;

[0127] 4. Operate the in-situ monitoring equipment for VOC gases in the soil. The control module 19 simultaneously records and monitors the second pressure value measured by the second pressure gauge 15 and the second flow value measured by the second flow meter 16.

[0128] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0129] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0130] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0131] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0132] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0133] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. An in-situ monitoring device for VOC gases in soil, characterized in that, it includes an in-situ monitoring rod group, an extraction influence range monitoring component, a gas detection device (3), an air pump (4) and a control module (19), The in-situ monitoring rod group includes a monitoring rod (1) and a probe (2) connected in sequence from top to bottom. The side wall of the monitoring rod (1) has a monitoring hole (101), and the side wall of the probe (2) has an extraction hole (201); The monitoring hole (101) is communicated with a monitoring pipeline, and the extraction influence range monitoring component is arranged on the monitoring pipeline, The extraction hole (201), the gas detection device (3) and the air pump (4) are sequentially communicated through an extraction pipeline, and the outlet of the air pump (4) is communicated with an exhaust pipeline; The control module (19) is respectively in communication connection with the extraction influence range monitoring component, the gas detection device (3) and the air pump (4); The in-situ monitoring device for VOC gases in soil further includes a gas collection device (5), and the outlet of the air pump (4) is respectively communicated with the exhaust pipeline and the gas collection device (5); The in-situ monitoring device for VOC gases in soil further includes a first solenoid valve (6), a second solenoid valve (7), a third solenoid valve (8) and a fourth solenoid valve (9) respectively in communication connection with the control module (19), The extraction hole (201), the first end of the first solenoid valve (6), the second end of the first solenoid valve (6), the gas detection device (3), the first end of the second solenoid valve (7), the second end of the second solenoid valve (7), the air pump (4), the first end of the third solenoid valve (8), the third end of the third solenoid valve (8), the first end of the fourth solenoid valve (9), the third end of the fourth solenoid valve (9) and the third end of the first solenoid valve (6) are sequentially communicated, The third end of the second solenoid valve (7) is communicated with an air inlet pipe (10), the second end of the third solenoid valve (8) is communicated with the exhaust pipeline, and the second end of the fourth solenoid valve (9) is communicated with the gas collection device (5); The extraction influence range monitoring component includes a first pressure gauge (11) and a first flow meter (12) connected to the monitoring pipeline; An air inlet pipe (10) is connected to the extraction pipeline between the gas detection device (3) and the air pump (4).

2. The in-situ monitoring device for VOC gases in soil according to claim 1, characterized in that, A gas treatment component and a suction pipe monitoring component are sequentially arranged on the suction pipe between the extraction hole (201) and the gas detection device (3), and the suction pipe monitoring component is in communication connection with the control module (19).

3. The in-situ monitoring device for VOC gases in soil according to claim 2, characterized in that, The gas treatment component includes a filter (13) and a dryer (14), and the filter (13) and the dryer (14) are connected in series on the suction pipe between the extraction hole (201) and the gas detection device (3); The exhaust pipe monitoring assembly includes a second pressure gauge (15) and a second flow meter (16), and the second pressure gauge (15) and the second flow meter (16) are respectively communicated with the exhaust pipe between the dryer (14) and the gas detection device (3); An exhaust filter (17) is arranged inside the end of the exhaust pipe communicating with the exhaust hole (201).

4. The in-situ monitoring device for VOC gas in soil according to any one of claims 1-3, characterized in that, The outlet of the exhaust gas pipe is also communicated with an exhaust gas treatment device (18); the in-situ monitoring rod group further includes a drill rod (21), and the drill rod (21), the monitoring rod (1) and the probe (2) are connected in sequence from top to bottom.

5. The in-situ monitoring device for VOC gas in soil according to any one of claims 1-3, characterized in that, It further includes a display and storage module (20), and the control module (19) is communicatively connected with the display and storage module (20).

6. An in-situ monitoring method for VOC gas in soil, characterized in that, The in-situ monitoring device for VOC gas in soil according to any one of claims 1-5 is adopted, and the method includes the following steps: The control module (19) switches the device to a preset mode, In the preset mode, the control module (19) adjusts the gas flow of the air pump (4) according to the influence range monitoring data measured by the extraction influence range monitoring assembly, or sets the gas flow of the air pump (4) according to experimental requirements, and the control module (19) obtains the gas parameter data measured by the gas detection device (3).

7. The in-situ monitoring method for VOC gas in soil according to claim 6, characterized in that, The outlet of the air pump (4) is respectively communicated with the exhaust gas pipe and a gas collection device (5), and the preset mode includes a gas monitoring mode and a sample collection mode; In the gas monitoring mode, the control module (19) controls the outlet of the air pump (4) to be switched to communicate with the exhaust gas pipe, and the control module (19) controls the exhaust hole (201), the gas detection device (3), the air pump (4) and the exhaust gas pipe to be communicated in sequence; In the sample collection mode, the control module (19) controls the outlet of the air pump (4) to be switched to communicate with the gas collection device (5), and the control module (19) controls the exhaust hole (201), the gas detection device (3), the air pump (4) and the gas collection device (5) to be communicated in sequence.

8. The in-situ monitoring method for VOC gas in soil according to claim 7, characterized in that, An exhaust pipe monitoring assembly communicatively connected with the control module (19) is further arranged on the exhaust pipe between the exhaust hole (201) and the gas detection device (3), and the control module (19) can also switch the device to a soil gas permeability test mode; In the soil gas permeability test mode, the control module (19) controls the intake pipe (10), the air pump (4) and the extraction hole (201) to be connected in sequence. The control module (19) adjusts the gas flow rate of the air pump (4) according to the influence range monitoring data measured by the extraction influence range monitoring component, or sets the gas flow rate of the air pump (4) according to the experimental requirements, and the control module (19) obtains the extraction pipe monitoring data measured by the extraction pipe monitoring component.

Images