Soil permeability rapid measurement device and method

Abstract

The present invention discloses a soil permeability rapid determination device and method, belonging to the field of soil quality determination equipment. The device includes an annular knife, an adjustable sleeve, a fixed sleeve and a data acquisition and processing module; the annular knife is used to collect target soil, and the two ends can be blocked by the adjustable sleeve and the fixed sleeve respectively so that the soil in the inner cavity of the annular knife is in a closed space, and the adjustable sleeve is provided with a push rod that can be inserted into the inner cavity of the annular knife to adjust the compaction of the soil; the data acquisition and processing module includes a power supply, a first pressure transmitter, a first electronic flow meter, a data integration processor, an air compressor, an exhaust gas purifier, a second electronic flow meter and a second pressure transmitter. The present invention can realize the measurement of constant pressure difference and variable pressure difference permeability of soil columns of different lengths by optimizing the structure and function of the equipment; using gas as the measurement medium can restore processes such as gas phase extraction and thermal desorption, guide site soil remediation work, and is flexible and portable, simple to operate, fast and accurate.

Description

Technical Field

[0001] The invention discloses a soil permeability rapid determination device and method, belonging to the field of soil quality determination equipment. Background Art

[0002] With rapid economic and social development, accelerated urbanization, and adjustments to industrial structures, approximately 300,000 industrial sites have been left behind due to industrial relocation. Long-term industrial activity has resulted in varying degrees of soil contamination at these sites, destroying their habitats and restricting the reuse of land resources. Therefore, remediation of industrially contaminated sites is a crucial component of current soil pollution prevention and control efforts. Numerous technologies are available for remediation of contaminated sites, with vapor phase extraction and thermal desorption being widely used due to their speed, flexibility, and ease of installation and operation.

[0003] The technical principle of vapor extraction and thermal desorption is to use ventilation and heating to desorb pollutants from the soil system. The desorbed pollutants are then transported with the carrier gas to the exhaust gas purification system for centralized treatment, completing the soil remediation work. Research on vapor extraction and thermal desorption technologies focuses not only on the removal time and efficiency of pollutants, but also on the interfacial behavior of pollutants in the soil multi-interface system. The desorption and migration process of pollutants in the soil system is modeled, calculated, and verified at the microscopic level, restoring the remediation process and achieving precise control. In this process, soil permeability is one of the necessary basic parameters. Accurately measuring soil permeability can effectively improve the accuracy and applicability of the model, enhance guidance effectiveness, save resources, reduce costs, and reduce energy consumption.

[0004] Soil permeability indicates how easily fluids flow through the soil and is a key parameter characterizing the rate of fluid flow through it. Soil permeability is related to factors such as soil texture, porosity, structure, and moisture content. Soils with a rough texture, large pores, good structure, and low moisture content have high permeability, allowing fluids to flow easily. Conversely, soils with low permeability are considered hypopermeable and difficult to flow through.

[0005] The principle of permeability K is based on Darcy's law. When a single-phase fluid (water or gas) flows in layers through a porous medium with a cross-sectional area of ​​A, a length of L, and a pressure difference of ΔP, and the fluid viscosity is μ, the flow rate Q passing through this porous medium per unit time is:

[0006]

[0007] The calculation formula of permeability is obtained by transformation:

[0008]

[0009] Soil permeability measurement methods primarily include the double-ring method, the knife-ring method, the constant-head permeameter method, the variable-head flux method, and the steady-state flux method. Most of these methods use water as the fluid medium, requiring multiple sampling and repeated testing. These processes are complex, making field measurements inconvenient, and lack effective guidance for remediation processes using gas as the primary fluid medium, such as vapor extraction and thermal desorption. Summary of the Invention

[0010] The present invention aims to overcome the shortcomings of the prior art and provide a device and method for rapidly measuring soil permeability. The present invention can rapidly and accurately measure soil permeability during site soil remediation work, filling a gap in similar products currently available in China.

[0011] The specific technical solutions adopted in the present invention are as follows:

[0012] The first invention provides a soil permeability rapid measurement device, comprising an annular knife, an adjustable sleeve, a fixed sleeve and a data acquisition and processing module;

[0013] The annular knife is used to collect target soil, and its two ends can be blocked by an adjustable sleeve and a fixed sleeve respectively, so that the soil in the annular knife cavity is in a closed space. The adjustable sleeve is provided with a push rod that can extend into the annular knife cavity to adjust the compaction of the soil; the adjustable sleeve is provided with a second air inlet and a first sensor interface for connecting an external pressure sensor to detect the gas inlet pressure, and the fixed sleeve is provided with a second air outlet and a second sensor interface for connecting an external pressure sensor to detect the gas outlet pressure.

[0014] The data acquisition and processing module includes a power supply, a first pressure transmitter, a first electronic flowmeter, a data integration processor, an air compressor, an exhaust gas purifier, a second electronic flowmeter and a second pressure transmitter; the power supply is used to power the electrical equipment, the detected gas inlet pressure can be transmitted to the data integration processor through the first pressure transmitter, and the detected gas outlet pressure can be transmitted to the data integration processor through the second pressure transmitter; the outlet of the air compressor is connected to the second air inlet through a pipeline provided with the first electronic flowmeter, for providing pressurized gas to the annular knife; the second air outlet is connected to the exhaust gas purifier through a pipeline provided with the second electronic flowmeter, and the first electronic flowmeter and the second electronic flowmeter are both connected to the data integration processor.

[0015] Preferably, the annular knife is a cylindrical structure, including a first end and a second end; the first end is provided with a cylindrical brim fixed on the outer periphery for increasing the striking force area, and the second end has an annular blade; the outer wall of the annular knife adjacent to the first end and the second end is provided with a thread for detachable connection with the adjustable sleeve and the fixed sleeve.

[0016] Preferably, it also includes a base of the box structure; an arc frame and a ring frame are detachably fixed on the top of the base, and there is a gap between the arc frame and the ring frame; the ring frame is used to connect the fixed sleeve, and the arc frame is used to support and place the ring knife, and the arc frame can be connected to the clip through a hinge to achieve the fixation of the ring knife.

[0017] Furthermore, the data acquisition and processing module is located inside the base; the first side of the base is provided with an electronic display screen for displaying data and a controller for controlling the equipment, the second side of the base is provided with a first transmitter interface, a second transmitter interface and a switch for controlling the power supply, the first sensor interface can be connected to the first pressure transmitter through a signal line via the first transmitter interface, and the second sensor interface can be connected to the second pressure transmitter through a signal line via the second transmitter interface; the third side of the base is provided with a first air inlet and a first air outlet, the first air inlet is connected to the inlet of the air compressor through a pipeline, and the pipeline connected to the outlet of the air compressor is connected to the second air inlet through the first air outlet; the fourth side of the base is provided with a third air inlet and a third air outlet, the pipeline connected to the second air outlet is connected to the second electronic flowmeter through the third air inlet, and the pipeline connected to the outlet of the exhaust purifier is connected to the outside world through the third air outlet.

[0018] Furthermore, a plurality of anti-slip pads are provided on the lower part of the base.

[0019] Preferably, one end of the fixed sleeve is used to connect with the annular knife, and the other end is fixed to the sealing cover through a flange; a second porous plate with a plate surface perpendicular to the gas flow direction is provided inside the fixed sleeve to intercept soil and limit the annular knife.

[0020] Preferably, a limiting member for limiting the position of the annular knife is provided inside the adjustable sleeve.

[0021] Preferably, the push rod is a screw structure, which is threadedly connected to the adjustable sleeve; one end of the push rod is provided with a rotating handle located outside the adjustable sleeve, and the other end is provided with a first porous plate located inside the adjustable sleeve; the plate surface of the first porous plate is perpendicular to the gas flow direction, and the cross-sectional size is the same as the cross-sectional size of the inner cavity of the annular knife, so as to adjust the soil compaction degree.

[0022] Preferably, the exhaust gas purifier is filled with activated carbon and the power source is a lithium battery.

[0023] In a second aspect, the present invention provides a method for rapidly measuring soil permeability using any of the soil permeability rapid measuring devices described in the first aspect, as follows:

[0024] Select the soil surface to be tested at the target site, and select a ring knife with an inner cross-sectional area of ​​A and an axial length of L according to the measurement depth; point the annular blade at the lower end of the ring knife toward the soil, and press it vertically into the soil 2 to 3 cm. Use a knocking tool to tap the tube edge at the upper end of the ring knife to make the annular blade reach the target depth, and then remove the ring knife with the soil sample; screw the lower end of the ring knife onto a fixed sleeve and the upper end onto an adjustable sleeve, so that the ring knife is placed horizontally, and use a push rod to adjust the compaction of the soil;

[0025] Connect the first sensor interface and the second sensor interface to external pressure sensors and turn on the power. After the medium gas is pressurized by an air pump, it enters the adjustable sleeve through the second air inlet. The inlet gas flow rate entering the adjustable sleeve is adjusted to Q1 by the first electronic flowmeter. The medium gas flows from the adjustable sleeve through the soil sample in the annular knife and enters the fixed sleeve. Then, it enters the exhaust gas purifier through the second air outlet. The outlet gas flow rate Q2 is detected by the second electronic flowmeter. The gas inlet pressure P1 and gas outlet pressure P2 are detected by the pressure sensor. The soil permeability K is calculated using the data integration processor according to the following formula:

[0026]

[0027] Where μ is the viscosity of the gas.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] (1) This invention uses gas as the measurement medium, making it well-suited for contaminated soil remediation using vapor phase extraction and thermal desorption techniques. Currently, permeability measurements take 4 to 8 hours, but this invention can increase measurement efficiency by fourfold, completing the measurement in just 1 to 2 hours.

[0030] (2) Gas as a measuring medium will not contaminate soil samples and can minimize damage to soil structure. One sampling can achieve measurement work under constant pressure difference and variable pressure difference conditions.

[0031] (3) The present invention can effectively adapt to the permeability measurement work of soil samples at different depths by adjusting the installation method of the auxiliary measurement module through structural optimization.

[0032] (4) The detachable annular blade, built-in lithium battery and modular design of the present invention improve the portability and maneuverability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the structure of the soil permeability rapid measurement equipment;

[0034] Figure 2 This is an exploded view of the soil permeability rapid determination equipment;

[0035] Figure 3 The following are the front view (a), side view (b) and top view (c) of the soil permeability rapid determination equipment;

[0036] Figure 4 The side view (a), AA cross-section (b), and BB cross-section (c) of the soil permeability rapid determination equipment are shown;

[0037] Figure 5 The front view (a), side view (b), top view (c) and structural diagram (d) of the annular knife;

[0038] Figure 6 The front view (a), side view (b), top view (c) and structural diagram (d) of the ejector pin are shown;

[0039] The accompanying drawings are marked as follows: 1, base, 2, electronic display screen, 3, first air inlet, 4, first air outlet, 5, arc frame, 6, second air inlet, 7, adjustable sleeve, 8, annular knife, 81, tube eaves, 82, annular blade, 9, fixed sleeve, 10, annular frame, 11, third air inlet, 12, third air outlet, 13, controller, 14, clip, 15, ejector rod, 151, rotating handle, 152, first porous plate, 16, first sensor interface, 1 7. First transmitter interface, 18. Second transmitter interface, 19. Second sensor interface, 20. Second air outlet, 21. Sealing cover, 22. Switch, 23. Hinge, 24. Anti-slip pad, 26. Limiter, 27. Second porous plate, 28. Power supply, 29. First pressure transmitter, 30. First electronic flow meter, 31. Data integration processor, 32. Air compressor, 33. Exhaust gas purifier, 34. Second electronic flow meter, 35. Second pressure transmitter. DETAILED DESCRIPTION

[0040] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention may be combined accordingly, provided that there is no conflict between them.

[0041] like Figures 1 to 3 The figure shows a rapid soil permeability measurement device provided by the present invention. This device primarily comprises a soil collection module, an auxiliary measurement module, and a data acquisition and processing module. By optimizing the device's structure and functionality, the present invention enables the measurement of permeability at both constant and variable pressure differentials in soil columns of varying lengths. Using gas as the measurement medium, it can replicate processes such as gas phase extraction and thermal desorption, guiding on-site soil remediation efforts. The device is flexible, portable, simple to operate, and rapid and accurate. The structure and connection methods of each module are described in detail below.

[0042] The soil collection module is used to collect soil samples and mainly includes an annular knife 8. Figure 5 As shown, in this embodiment, the annular knife 8 can be set to a cylindrical structure, including a first end and a second end, which can be knocked into the soil to be tested to collect samples during the implementation process. In order to increase the force-bearing area of ​​the annular knife, withstand the greater force from the knocking tool, and prevent the annular knife and the knocking tool from being directly deformed, which affects the collection of samples and the accuracy of measurement, a fixed tube eave 81 is provided on the outer surface of the first end of the annular knife, and the tube eave 81 is an annular structure with a flat upper surface. The second end has an annular blade 82 to reduce resistance and facilitate breaking the soil when pressed in. The outer wall of the annular knife 8 adjacent to the first end and the second end is provided with a thread for detachable connection with the adjustable sleeve 7 and the fixed sleeve 9, and the adjustable sleeve 7 and the fixed sleeve 9 are used to seal so that the soil in the inner cavity of the annular knife 8 is in a closed space.

[0043] The auxiliary measurement module mainly includes an adjustable sleeve 7 and a fixed sleeve 9. In this embodiment, the auxiliary measurement module also includes a push rod 15, an arc frame 5, a circular frame 10, a sealing cover 21, a base 1 and matching air pipes and signal lines, which are used to connect components such as annular knives, flow meters and sensors to assist in forming a closed chamber required for measurement.

[0044] like Figure 4 As shown, the base 1 is a box structure, and an arc frame 5 and an annular frame 10 are detachably fixed on the top thereof. There is a gap between the arc frame 5 and the annular frame 10 to better support the two ends of the annular knife so that it is placed in a horizontal state. The annular frame 10 is used to connect the fixed sleeve 9. The fixed sleeve 9 is a hollow structure, and a detachable connection thread is set on the inner wall of the left end for screwing the annular knife 8. A second porous plate 27 is provided inside with the plate surface perpendicular to the direction of gas flow, which is used to intercept soil and limit the annular knife 8. The right end is fixed to the sealing plate 21 through a flange, and the flange has a built-in sealing gasket to maintain airtightness. A second air outlet 20 and a second sensor interface 19 for an external pressure sensor to detect the gas outlet pressure are provided on the fixed sleeve 9. The arc frame 5 is used to support the annular knife 8. The arc frame 5 is connected to the clip 14 through a hinge 23 to fix the annular knife 5 and is locked by a bolt.

[0045] Specifically, the adjustable sleeve 7 is a hollow structure, and a detachably connected threaded annular knife 8 is provided on the inner wall of the right end; a limit block 26 is provided inside to limit the screw-in distance of the annular knife, and the middle section of the limit member 26 is hollowed out to facilitate gas circulation and pressure measurement; a threaded hole is provided on the left end to facilitate the passage of the push rod 15, and a sealing rubber ring is provided on the hole to ensure air tightness; a first force sensor interface 16.

[0046] like Figure 6As shown, push rod 15 is a screw structure, threadedly connected to adjustable sleeve 7. One end of push rod 15 is equipped with a rotating handle 151 located outside adjustable sleeve 7, and the other end is equipped with a first porous plate 152 located inside adjustable sleeve 7. The plate surface of first porous plate 152 is perpendicular to the direction of gas flow, and its cross-sectional dimensions are the same as the cross-sectional dimensions of the inner cavity of annular blade 8, so as to adjust soil compaction while retaining soil and allowing the measurement fluid to pass through.

[0047] The data acquisition and processing module mainly includes a power supply 28, a first pressure transmitter 29, a first electronic flowmeter 30, a data integration processor 31, an air compressor 32, an exhaust gas purifier 33, a second electronic flowmeter 34, and a second pressure transmitter 35. The power supply 28 supplies power to the device. The gas inlet pressure detected by the pressure sensor can be transmitted as a signal to the data integration processor 31 via the first pressure transmitter 29, and the detected gas outlet pressure can be transmitted as a signal to the data integration processor 31 via the second pressure transmitter 35. The outlet of the air compressor 32 is connected to the second air inlet 6 via a pipeline equipped with the first electronic flowmeter 30, which is used to provide pressurized gas to the annular blade 8. The second air outlet 20 is connected to the exhaust gas purifier 33 via a pipeline equipped with the second electronic flowmeter 34. The first electronic flowmeter 30 and the second electronic flowmeter 34 are both connected to the data integration processor 31.

[0048] In this embodiment, the data acquisition and processing module is located within the base 1. The first side of the base 1 is provided with an electronic display screen 2 for displaying data and a controller 13 for operating the device. The second side of the base 1 is provided with a first transmitter interface 17, a second transmitter interface 18, and a switch 22 for controlling a power supply 28. The first sensor interface 16 can be connected to a first pressure transmitter 29 via a signal line through the first transmitter interface 17, and the second sensor interface 19 can be connected to a second pressure transmitter 35 via a signal line through the second transmitter interface 18. The third side of the base 1 is provided with a first air inlet 3 and a first air outlet 4. The first air inlet 3 is connected to the inlet of an air pump 32 via a pipeline. The outlet of the air pump 32 is connected to the second air inlet 6 via a first electronic flowmeter 30 and the first air outlet 4. The fourth side of the base 1 is provided with a third air inlet 11 and a third air outlet 12. The pipe connected to the second air outlet 20 is connected to the second electronic flow meter 34 via the third air inlet 11. The pipe connected to the outlet of the exhaust purifier 33 is connected to the outside world via the third air outlet 12. Four anti-slip pads 24 are provided on the bottom of the base to prevent the equipment from slipping.

[0049] Specifically, the lithium battery provides electric power for the equipment, and no external power supply is required; the first pressure transmitter 29 and the second pressure transmitter 35 transmit the data collected by the pressure sensor to the data integration processor 31; the first electronic flow meter 30 and the second electronic flow meter 34 collect real-time flow data and transmit it to the data integration processor 31, and the processed data is displayed on the electronic display screen 2; the data integration processor 31 records and processes the collected data, and based on Darcy's law, calculates the soil permeability through built-in parameters and algorithms; the air compressor 32 provides power for fluid flow; the exhaust purifier 33 is filled with activated carbon to adsorb pollutants and reduce unorganized pollutant emissions.

[0050] The soil permeability rapid measurement method using the above soil permeability rapid measurement equipment is as follows:

[0051] At the site to be measured, select an appropriate soil surface, determine the measurement depth, select a circular blade, and measure the internal cross-sectional area A and length L of the circular blade. With the lower circular blade facing the soil, press the blade vertically into the soil for 2-3 cm. Use a striking tool to tap the edge of the circular blade barrel. Once the measurement depth is reached, remove the circular blade to obtain a soil sample. Place the circular blade with the soil sample on the curved stand. Thread the lower end of the circular blade onto the fixed sleeve. Screw the front end of the blade into the second porous plate. Secure the circular blade with a clip. Thread the upper end of the circular blade onto the adjustable sleeve and tighten until the barrel edge mates with the stopper. Twist the handle to tighten the push rod to compress the soil. Connect the first air outlet to the second air inlet, and the second air outlet to the third air inlet, via an air pipe. Connect the first sensor connector to the first transmitter interface, and the second sensor connector to the second transmitter interface, using a signal cable. Connect the medium gas to the first air inlet, turn on the base switch, set the flow rate Q1 of the second air inlet, input the inner cross-sectional area A, length L of the annular blade, and the viscosity μ of the measured gas, and the data acquisition and processing module collects the first pressure sensor P1, the second pressure sensor P2, and the flow rate Q2 of the third air inlet. The soil permeability is determined based on Darcy's law, taking into account the compressibility of the gas. The calculation formula is as follows:

[0052]

[0053] The data acquisition and processing module processes the data according to the set parameters, input parameters and built-in algorithms to obtain the soil permeability.

[0054] Specifically, the first sensor interface 16 is connected to the first transmitter interface 17 via a signal line. The first sensor interface 16 is used to connect to an external sensor. The first transmitter interface 17 is connected to the first pressure transmitter 29 for measuring the gas pressure at the annular blade inlet. The second sensor interface 19 is connected to the second transmitter interface 18 via a signal line. The second sensor interface 19 is used to connect to an external sensor. The second transmitter interface 18 is connected to the second pressure transmitter 35 for measuring the gas pressure at the annular blade outlet.

[0055] During the measurement process, the gas flow path is briefly described as follows:

[0056] The gas medium enters the air pump through the first air inlet 3 through the pipeline, flows out of the air pump through the pipeline after compression, and enters the adjustable sleeve 7 through the first air outlet 4 and the second air inlet 6, then enters the fixed sleeve 9 after passing through the soil sample, flows out from the second air outlet 20 through the pipeline and the third air inlet 11 to be connected to the second electronic flowmeter 34, the second electronic flowmeter 34 is connected to the exhaust purifier 33, and the gas treated by the exhaust purifier 33 is discharged through the third air outlet 12.

[0057] This invention enables rapid and accurate measurement of contaminated soil permeability at sites, resolving the complex workflow, long measurement times, and limited flexibility of traditional methods. Using gas as the measurement medium better simulates the remediation processes of vapor extraction and thermal desorption, providing more instructive results. Optimized components such as a detachable ring blade, a built-in lithium battery, and a modular design ensure the device's portability and maneuverability, meeting the needs of site soil remediation work.

[0058] The above embodiment is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Persons skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, any technical solution obtained by equivalent substitution or equivalent transformation falls within the scope of protection of the present invention.

Claims

1. A soil permeability rapid measurement device, characterized in that: It comprises an annular knife (8), an adjustable sleeve (7), a fixed sleeve (9) and a data acquisition and processing module; The annular knife (8) is used to collect target soil, and its two ends can be blocked by an adjustable sleeve (7) and a fixed sleeve (9) respectively so that the soil in the inner cavity of the annular knife (8) is in a closed space. The adjustable sleeve (7) is provided with a push rod (15) that can extend into the inner cavity of the annular knife (8) to adjust the compaction degree of the soil; the adjustable sleeve (7) is provided with a second air inlet (6) and a first sensor interface (16) for connecting an external pressure sensor to detect the gas inlet pressure, and the fixed sleeve (9) is provided with a second air outlet (20) and a second sensor interface (19) for connecting an external pressure sensor to detect the gas outlet pressure. The data acquisition and processing module comprises a power supply (28), a first pressure transmitter (29), a first electronic flow meter (30), a data integration processor (31), an air compressor (32), an exhaust gas purifier (33), a second electronic flow meter (34) and a second pressure transmitter (35); the power supply (28) is used to supply power to the electrical equipment, the detected gas inlet pressure can be transmitted as a signal to the data integration processor (31) through the first pressure transmitter (29), and the detected gas outlet pressure can be transmitted as a signal to the data integration processor (31) through the second pressure transmitter (35); the outlet of the air compressor (32) is connected to the second air inlet (6) through a pipeline provided with the first electronic flow meter (30) for providing pressurized gas to the annular blade (8); the second air outlet (20) is connected to the exhaust gas purifier (33) through a pipeline provided with the second electronic flow meter (34), and both the first electronic flow meter (30) and the second electronic flow meter (34) are connected to the data integration processor (31); The invention also comprises a base (1) of a box structure; an arc frame (5) and an annular frame (10) are detachably fixed on the top of the base (1); a gap is provided between the arc frame (5) and the annular frame (10); the annular frame (10) is used for connecting and fixing the sleeve (9); the arc frame (5) is used for supporting and placing the annular knife (8); the arc frame (5) can be connected to the clip (14) through a hinge (23) to achieve the fixation of the annular knife (8).

2. A soil permeability rapid measurement device according to claim 1, characterized in that: The annular knife (8) is a cylindrical structure, comprising a first end and a second end; the first end is provided with a cylindrical flange (81) fixed on the outer surface thereof for increasing the striking force area, and the second end is provided with an annular blade (82); the outer wall of the annular knife (8) adjacent to the first end and the second end is provided with a thread for detachably connecting with the adjustable sleeve (7) and the fixed sleeve (9).

3. A soil permeability rapid measurement device according to claim 1, characterized in that: The data acquisition and processing module is located inside the base (1); the first side of the base (1) is provided with an electronic display screen (2) for displaying data and a controller (13) for operating the device; the second side of the base (1) is provided with a first transmitter interface (17), a second transmitter interface (18) and a switch (22) for controlling the power supply (28); the first sensor interface (16) can be connected to the first pressure transmitter (29) through a signal line via the first transmitter interface (17); the second sensor interface (19) can be connected to the second pressure transmitter (29) through a signal line via the second transmitter interface (18). The first air inlet (3) and the first air outlet (4) are provided on the third side of the base (1); the first air inlet (3) is connected to the inlet of the air pressure pump (32) through a pipeline; the pipeline connected to the outlet of the air pressure pump (32) is connected to the second air inlet (6) through the first air outlet (4); the fourth side of the base (1) is provided with a third air inlet (11) and a third air outlet (12); the pipeline connected to the second air outlet (20) is connected to the second electronic flow meter (34) through the third air inlet (11); the pipeline connected to the outlet of the exhaust purifier (33) is connected to the outside through the third air outlet (12).

4. A soil permeability rapid measurement device according to claim 1, characterized in that: A plurality of anti-slip pads (24) are provided at the lower part of the base (1).

5. A soil permeability rapid measurement device according to claim 1, characterized in that: One end of the fixed sleeve (9) is used to connect with the annular knife (8), and the other end is fixedly connected to the sealing cover (21) through a flange; a second porous plate (27) is provided inside the fixed sleeve (9) with the plate surface perpendicular to the gas flow direction, which is used to intercept soil and limit the annular knife (8).

6. A soil permeability rapid measurement device according to claim 1, characterized in that: A limiting member (26) for limiting the position of the annular knife (8) is provided inside the adjustable sleeve (7).

7. A soil permeability rapid measurement device according to claim 1, characterized in that: The push rod (15) is a screw structure and is threadedly connected to the adjustable sleeve (7); one end of the push rod (15) is provided with a rotating handle (151) located outside the adjustable sleeve (7), and the other end is provided with a first porous plate (152) located inside the adjustable sleeve (7); the plate surface of the first porous plate (152) is perpendicular to the gas flow direction, and the cross-sectional size is the same as the cross-sectional size of the inner cavity of the annular knife (8) so as to adjust the soil compaction degree.

8. A soil permeability rapid measurement device according to claim 1, characterized in that: The tail gas purifier (33) is filled with activated carbon, and the power source (28) is a lithium battery.

9. A method for rapidly measuring soil permeability using the soil permeability rapid measuring device according to any one of claims 1 to 8, characterized in that: The details are as follows: A soil surface to be tested is selected at a target site, and an annular knife (8) having an inner cross-sectional area of ​​A and an axial length of L is selected according to the test depth; the annular blade (82) at the lower end of the annular knife (8) is directed toward the soil and pressed vertically into the soil by 2 to 3 cm, and a knocking tool is used to knock the tube edge (81) at the upper end of the annular knife (8) so that the annular blade (82) reaches the target depth, and then the annular knife (8) with the soil sample is taken out; the lower end of the annular knife (8) is screwed to a fixed sleeve (9), and the upper end is screwed to an adjustable sleeve (7), so that the annular knife (8) is placed horizontally, and a push rod (15) is used to adjust the compaction degree of the soil; The first sensor interface (16) and the second sensor interface (19) are both connected to external pressure sensors, and the power supply (28) is turned on; after the medium gas is pressurized by the air pump (32), it is passed into the adjustable sleeve (7) through the second air inlet (6), and the inlet gas flow rate entering the adjustable sleeve (7) is adjusted to Q1 by the first electronic flow meter (30); the medium gas flows from the adjustable sleeve (7) through the soil sample in the annular knife (8) and enters the fixed sleeve (9), and then enters the tail gas purifier (33) through the second air outlet (20) and the second electronic flow meter (34), and the outlet gas flow rate Q2 is detected by the second electronic flow meter (34); the gas inlet pressure P1 and the gas outlet pressure P2 are detected by the pressure sensor, and the soil permeability K is calculated according to the following formula using the data integration processor (31): Where μ is the viscosity of the gas.

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