Device for quickly estimating content of massive ice in permafrost and use method of device

Abstract

The invention relates to a device for quickly estimating the content of massive ice in permafrost. The device comprises a closed cubic test space formed by side plates, a bottom plate and a cover plate. An infrared imager is embedded in the center position of the cover plate; a fixed constant-temperature cold source is arranged in the closed cubic test space, and a frozen soil sample is arranged above the fixed constant-temperature cold source; a movable constant-temperature cold source is arranged above the frozen soil sample, and a pair of constant-temperature cold source handles are symmetrically arranged on the two sides of the movable constant-temperature cold source; a circulating pump, a constant-temperature liquid storage tank and a cooling chamber which are sequentially connected in series through a pipeline are arranged outside the closed cubic test space; the output end of the circulating pump is respectively connected with injection ports of the movable constant-temperature cold source and the fixed constant-temperature cold source; and one end of the cooling chamber is respectively connected with the outlet of the movable constant-temperature cold source and the outlet of the fixed constant-temperature cold source. Meanwhile, the invention further discloses a using method of the device. The device can be used for on-site sampling to realize rapid testing, and the low-temperature transportation cost of the sample is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of rapid estimation of block ice content in permafrost areas, and in particular to a device for rapid estimation of block ice content in permafrost areas and a method for using the device. Background Art

[0002] Permafrost is an ice-containing, negative-temperature geological body that is extremely sensitive to temperature and external factors. Its presence of underground ice is its most fundamental difference from other rock and soil bodies. Permafrost, a layer of soil frozen for more than two years, is both a low-temperature environment and a medium. Permafrost is a product of both the interaction of the earth's atmosphere and geological history. Intensified climate warming is causing significant degradation of permafrost, accelerating the melting of underground ice, significantly altering hydrological processes and water resource distribution in permafrost regions, disrupting ecosystem stability, and upsetting the carbon balance, thus severely impacting regional ecological environments and sustainable development. Therefore, research on the content of massive ice in permafrost regions is of great practical significance.

[0003] Currently, the monitoring of underground ice content and distribution characteristics in permafrost areas is mainly carried out through two means: (1) ground penetrating radar technology and (2) remote sensing technology. However, the spatial heterogeneity of underground ice in permafrost areas is strong, the occurrence mechanism is unclear, and the change process is complex. The results of ground penetrating radar and remote sensing analysis need to be verified and supported by field survey data. At the same time, the cost of low-temperature transportation after on-site sampling is high, and there is a lack of effective in-situ monitoring methods for the bulk ice content of undisturbed frozen soil samples. Therefore, there is an urgent need for a device that can quickly estimate the bulk ice content of frozen soil and achieve rapid estimation of the bulk ice content of permafrost soil. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a device for rapidly estimating the content of block ice in permafrost soil, which reduces the test cost.

[0005] Another technical problem to be solved by the present invention is to provide a method for using the device for rapidly estimating the content of block ice in permafrost.

[0006] To address the above-mentioned problems, the present invention provides a device for rapidly estimating the block ice content of permafrost, characterized in that: the device includes a closed cubic test space formed by side panels, a bottom panel, and a cover panel; an infrared imager wirelessly or wiredly connected to a computer is embedded in the center of the cover panel; a fixed constant-temperature cold source is provided within the closed cubic test space, closely attached to the bottom panel, and a frozen soil sample is provided above the fixed constant-temperature cold source; a movable constant-temperature cold source is provided above the frozen soil sample, and a pair of constant-temperature cold source handles are symmetrically provided on both sides of the movable constant-temperature cold source; a circulating pump, a constant-temperature liquid storage tank, and a cooling chamber are provided outside the closed cubic test space, which are connected in series via pipes; the output end of the circulating pump is connected to the injection ports of the movable constant-temperature cold source and the fixed constant-temperature cold source, respectively, via a refrigerant injection pipe; and one end of the cooling chamber is connected to the outlet ports of the movable constant-temperature cold source and the fixed constant-temperature cold source, respectively, via a refrigerant outlet pipe.

[0007] The rear side of the cover plate is connected to the side plate through a hinge; a pair of cover plate handles are symmetrically provided on the outer side of the front end of the cover plate.

[0008] The side panels, the bottom panel and the cover panel are all made of two layers of acrylic panels, and the interlayer of the acrylic panels is filled with thermal insulation material.

[0009] A sealing gasket is provided on the contact surface between the cover plate and the side plate.

[0010] The imaging range of the infrared imager is equivalent to the area of ​​the frozen soil sample.

[0011] The movable constant temperature cold source and the fixed constant temperature cold source are both composed of an S-shaped liquid circulation channel surrounded by panels and partitions, and their thickness is 5-10 cm. The plane size is the same as the size of the bottom plate inside the closed cubic test space.

[0012] A pair of pipe holes I are symmetrically provided on both sides of the side plate connected to the bottom plate; a pair of pipe holes II are symmetrically provided on both sides of the side plate connected to the cover plate; quick connectors are provided in both the pipe hole I and the pipe hole II; the refrigerant injection pipe is connected by pipeline I and pipeline II through a tee I; the pipeline I is connected to the injection port of the fixed constant temperature cold source through the quick connector on the pipeline hole I; the pipeline II extends into the interior of the closed cube test space through the quick connector on the pipeline hole II, and is connected to the injection port of the movable constant temperature cold source; the refrigerant outlet pipe is connected by pipeline III and pipeline IV through a tee II; the pipeline III is connected to the outlet of the fixed constant temperature cold source through the quick connector on the pipeline hole I; the pipeline IV extends into the interior of the closed cube test space through the quick connector on the pipeline hole II, and is connected to the outlet of the movable constant temperature cold source.

[0013] The thickness of the frozen soil sample is 1-5 cm, and the plane size is the same as that of the fixed constant temperature cold source.

[0014] A method for using the device for rapidly estimating the content of bulk ice in permafrost as described above comprises the following steps: (1) Dig a test pit at the site to be tested. When the depth of the test pit reaches the permafrost layer, use a sampling device to collect frozen soil samples layer by layer. The thickness of the collected frozen soil samples is 1~5cm, and the plane size is the same as that of the fixed constant temperature cold source; (2) Open the cover, take out the movable constant temperature cold source, apply vaseline on the lower surface of the movable constant temperature cold source and the upper surface of the fixed constant temperature cold source, place the frozen soil sample on the fixed constant temperature cold source, put the movable constant temperature cold source back, and inject a constant temperature liquid with a temperature of -3℃ ~ -5℃ into the movable constant temperature cold source and the fixed constant temperature cold source to keep the frozen soil sample at a constant temperature; (3) After the frozen soil sample reaches a constant temperature state, the cover is opened, the movable constant temperature cold source is removed, and a constant temperature liquid with a temperature of -10°C to -15°C is injected into the internal circulation of the fixed constant temperature cold source. The infrared imager is controlled by a computer and infrared images of the frozen soil sample are continuously collected until the upper surface temperature of the frozen soil sample approaches the temperature of the constant temperature liquid with a temperature of -10°C to -15°C; (4) Import the collected infrared images of the upper surface of the frozen soil sample into the computer, analyze the temporal variation of the upper surface temperature, interpret the block ice area in the frozen soil sample, determine the outline of the block ice distribution area, and calculate the block ice volume of the frozen soil sample using the following formula: The volume of block ice in a single group of frozen soil samples = the area of ​​block ice distribution × the thickness of the frozen soil sample; (5) By testing multiple sets of continuous frozen soil samples, the block ice areas of the interpreted sets of frozen soil samples are stacked in a computer, and the block ice distribution at the detection point is reconstructed in three dimensions to understand the macroscopic structure and distribution characteristics of the block ice; (6) By stacking the block ice areas of multiple groups of permafrost samples, calculate the permafrost block ice content at the detection point according to the following formula: Lump ice content = the sum of the volumes of lump ice in multiple groups of frozen soil samples / the sum of the volumes of multiple groups of frozen soil samples.

[0015] The constant temperature liquid in step (2) and step (3) is hydraulic oil.

[0016] Compared with the prior art, the present invention has the following advantages: 1. The present invention utilizes the difference in thermal conductivity between bulk ice and soil in permafrost. By placing one end face of a thin permafrost sample in a constant temperature state in contact with a constant temperature refrigerant, and using an infrared imager to continuously record the temperature change pattern of the other end face, the bulk ice area in the permafrost sample is interpreted, stacked, and three-dimensionally reconstructed, thereby achieving a rapid estimation of the bulk ice content in the permafrost sample.

[0017] 2. In the present invention, undisturbed samples are collected for testing, and through three-dimensional reconstruction, the macroscopic structure and distribution characteristics of block ice in permafrost samples can be indirectly understood.

[0018] 3. The present invention can take samples in the field for rapid testing, which reduces the cost of low-temperature transportation of samples compared to indoor testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0020] Figure 1 A three-dimensional cross-sectional view of the device for rapidly estimating the block ice content in frozen soil according to the present invention.

[0021] Figure 2 This is a front view of the device for rapidly estimating the block ice content in frozen soil according to the present invention.

[0022] Figure 3 It is a structural schematic diagram of the movable constant temperature cold source in the present invention.

[0023] Figure 4 It is a structural schematic diagram of the fixed constant temperature cold source in the present invention.

[0024] Figure 5 The present invention is a flowchart of the device for rapidly estimating the content of block ice in frozen soil.

[0025] Figure 6 This is a schematic diagram of block ice distribution obtained by computer interpretation of infrared images of a single frozen soil sample in the present invention.

[0026] In the figure: 1-side panel, 2-bottom plate, 3-cover plate, 4-hinge, 5-infrared imager, 6-cover plate handle, 7-movable constant temperature cold source, 8-fixed constant temperature cold source, 9-constant temperature cold source handle, 10-frozen soil sample, 11-sealing gasket, 121-pipe hole I, 122-pipe hole II, 13-panel, 14-partition, 15-liquid circulation channel, 16-refrigerant injection pipe, 17-refrigerant outlet pipe, 18-quick connector, 19-circulation pump, 20-constant temperature liquid storage tank, 21-cooling chamber. DETAILED DESCRIPTION

[0027] like Figures 1-4As shown, a device for rapidly estimating the block ice content of permafrost soil comprises a closed cubic test space formed by side panels 1, a bottom panel 2, and a cover panel 3. An infrared imager 5 connected to a computer wirelessly or by wire is embedded in the center of the cover panel 3. A fixed constant-temperature cold source 8 is provided within the closed cubic test space, closely attached to the bottom panel 2. A frozen soil sample 10 is provided above the fixed constant-temperature cold source 8. A movable constant-temperature cold source 7 is provided above the frozen soil sample 10. A pair of constant-temperature cold source handles 9 are symmetrically provided on either side of the movable constant-temperature cold source 7. A circulating pump 19, a constant-temperature liquid storage tank 20, and a cooling chamber 21 are provided outside the closed cubic test space, which are connected in series via pipes. The output end of the circulating pump 19 is connected to the injection ports of the movable constant-temperature cold source 7 and the fixed constant-temperature cold source 8, respectively, via a refrigerant injection pipe 16. One end of the cooling chamber 21 is connected to the outlet ports of the movable constant-temperature cold source 7 and the fixed constant-temperature cold source 8, respectively, via a refrigerant outlet pipe 17.

[0028] Among them: the rear side of the cover plate 3 is connected to the side plate 1 through a hinge 4; a pair of cover plate handles 6 are symmetrically provided on the outer side of the front end of the cover plate 3.

[0029] The side panels 1 , the bottom panel 2 and the cover panel 3 are all made of two layers of acrylic panels, and the interlayer of the acrylic panels is filled with thermal insulation material.

[0030] A sealing gasket 11 is provided on the contact surface between the cover plate 3 and the side plate 1 .

[0031] The imaging range of the infrared imager 5 is equivalent to the area of ​​the frozen soil sample 10 .

[0032] The movable constant temperature cold source 7 and the fixed constant temperature cold source 8 are both composed of an S-shaped liquid circulation channel 15 surrounded by a panel 13 and a partition 14, and the thickness of each channel is 5 to 10 cm. The plane size is the same as that of the inner bottom plate 2 of the closed cubic test space.

[0033] A pair of pipe holes I 121 are symmetrically provided on both sides of the side plate 1 connected to the bottom plate 2; a pair of pipe holes II 122 are symmetrically provided on both sides of the side plate 1 connected to the cover plate 3; quick connectors 18 are provided in both pipe holes I 121 and pipe holes II 122; the refrigerant injection pipe 16 is connected by pipeline I and pipeline II through a tee I; pipeline I is connected to the injection port of the fixed constant temperature cold source 8 through the quick connector 18 on the pipeline hole I 121; pipeline II extends into the interior of the closed cubic test space through the quick connector 18 on the pipeline hole II 122 and is connected to the injection port of the movable constant temperature cold source 7; the refrigerant outlet pipe 17 is connected by pipeline III and pipeline IV through a tee II; pipeline III is connected to the outlet of the fixed constant temperature cold source 8 through the quick connector 18 on the pipeline hole I 121; pipeline IV extends into the interior of the closed cubic test space through the quick connector 18 on the pipeline hole II 122 and is connected to the outlet of the movable constant temperature cold source 7.

[0034] The thickness of the frozen soil sample 10 is 1-5 cm, and its plane size is the same as that of the fixed constant temperature cold source 8 .

[0035] Working principle of the present invention: Taking advantage of the difference in thermal conductivity between block ice and soil in permafrost, the lower end surface of a thin sheet of frozen soil sample 10 in a constant temperature state is brought into contact with a fixed constant temperature cold source 8. With the help of an infrared imager 5, the temperature change pattern of its upper end surface is continuously recorded. The block ice area in the frozen soil sample 10 is interpreted, stacked and three-dimensionally reconstructed, thereby achieving a rapid estimation of the block ice content in the frozen soil sample 10.

[0036] like Figure 5 As shown, a method for using a device for rapidly estimating the content of bulk ice in permafrost comprises the following steps: (1) A test pit is excavated at the site to be tested. When the depth of the test pit reaches the permafrost layer, a sampling device is used to collect frozen soil samples 10 layer by layer. The collected frozen soil samples 10 are 1 to 5 cm thick and have the same plane dimensions as the fixed constant temperature cold source 8. The sampling device can be a device such as that shown in ZL2022200167029 for sampling and trimming the circular permafrost sample to the same size and shape as the fixed constant temperature cold source 8. (2) Open the cover 3, take out the movable constant temperature cold source 7, apply vaseline on the lower surface of the movable constant temperature cold source 7 and the upper surface of the fixed constant temperature cold source 8, place the frozen soil sample 10 on the fixed constant temperature cold source 8, replace the movable constant temperature cold source 7, and inject a constant temperature liquid with a temperature of -3°C to -5°C into the movable constant temperature cold source 7 and the fixed constant temperature cold source 8 to keep the frozen soil sample 10 constant temperature; the constant temperature liquid is hydraulic oil; (3) After the frozen soil sample 10 reaches a constant temperature state, the cover 3 is opened, the movable constant temperature cooling source 7 is removed, and a constant temperature liquid with a temperature of -10°C to -15°C is injected into the internal circulation of the fixed constant temperature cooling source 8. The constant temperature liquid is hydraulic oil; the infrared imager 5 is controlled by a computer and continuously captures infrared images of the frozen soil sample 10 until the upper surface temperature of the frozen soil sample 10 approaches the temperature of the constant temperature liquid with a temperature of -10°C to -15°C; (4) Import the infrared image of the upper surface of the frozen soil sample 10 collected into the computer, analyze the temporal variation of the upper surface temperature, interpret the block ice area in the frozen soil sample 10, and determine the outline of the block ice distribution area, such as Figure 6 As shown in the figure, the square area is permafrost sample 10, and the irregular area is the distribution area of ​​block ice obtained by infrared image interpretation. The volume of block ice in permafrost sample 10 is calculated using the following formula: The volume of block ice in a single group of frozen soil sample 10 = the area of ​​block ice distribution area × the thickness of frozen soil sample 10; (5) By testing multiple sets of continuous frozen soil samples 10, the block ice areas of the multiple sets of frozen soil samples 10 obtained by interpretation are stacked in a computer, and the block ice distribution at the detection point is reconstructed in three dimensions to understand the macroscopic structure and distribution characteristics of the block ice; (6) By stacking the block ice areas of multiple groups of frozen soil samples 10, the permafrost block ice content at the detection point is calculated according to the following formula: Lump ice content = the sum of the volumes of lump ice in multiple groups of frozen soil samples 10 / the sum of the volumes of multiple groups of frozen soil samples 10.

Claims

1. A device for rapidly estimating the bulk ice content of permafrost, characterized by: The device comprises a closed cubic test space formed by side plates (1), a bottom plate (2) and a cover plate (3); an infrared imager (5) connected to a computer wirelessly or by wire is embedded in the center of the cover plate (3); a fixed constant temperature cold source (8) in close contact with the bottom plate (2) is provided inside the closed cubic test space, and a frozen soil sample (10) is provided above the fixed constant temperature cold source (8); a movable constant temperature cold source (7) is provided above the frozen soil sample (10), and a pair of constant temperature cold sources are symmetrically provided on both sides of the movable constant temperature cold source (7). Source handle (9); the outside of the closed cubic test space is provided with a circulation pump (19), a constant temperature liquid storage tank (20) and a cooling chamber (21) which are sequentially connected in series through pipelines; the output end of the circulation pump (19) is connected to the injection ports of the movable constant temperature cold source (7) and the fixed constant temperature cold source (8) respectively through a refrigerant injection pipeline (16); one end of the cooling chamber (21) is connected to the outlet ports of the movable constant temperature cold source (7) and the fixed constant temperature cold source (8) respectively through a refrigerant outlet pipeline (17).

2. The device for rapidly estimating the content of block ice in permafrost according to claim 1, characterized in that: The rear side of the cover plate (3) is connected to the side plate (1) via a hinge (4); a pair of cover plate handles (6) are symmetrically provided on the outer side of the front end of the cover plate (3).

3. The device for rapidly estimating the content of block ice in permafrost according to claim 1, characterized in that: The side panels (1), the bottom panel (2) and the cover panel (3) are all made of two layers of acrylic panels, and the acrylic panel interlayer is filled with thermal insulation material.

4. The device for rapidly estimating the content of block ice in permafrost according to claim 1, characterized in that: A sealing gasket (11) is provided on the contact surface between the cover plate (3) and the side plate (1).

5. The device for rapidly estimating the content of block ice in permafrost according to claim 1, characterized in that: The imaging range of the infrared imager (5) is equivalent to the area of ​​the frozen soil sample (10).

6. The device for rapidly estimating the content of block ice in permafrost according to claim 1, characterized in that: The movable constant temperature cold source (7) and the fixed constant temperature cold source (8) are both composed of an S-shaped liquid circulation channel (15) formed by a panel (13) and a partition (14), and the thickness of each channel is 5 to 10 cm. The plane size is the same as the size of the bottom plate (2) inside the closed cubic test space.

7. The device for rapidly estimating the content of block ice in permafrost according to claim 1, characterized in that: A pair of pipe holes I (121) are symmetrically provided on both sides of the side plate (1) connected to the bottom plate (2); a pair of pipe holes II (122) are symmetrically provided on both sides of the side plate (1) connected to the cover plate (3); quick connectors (18) are provided in the pipe holes I (121) and the pipe holes II (122); the refrigerant injection pipe (16) is connected by pipeline I and pipeline II through a tee I; the pipeline I is connected to the injection port of the fixed constant temperature cold source (8) through the quick connector (18) on the pipeline hole I (121); the pipeline II is connected to the injection port of the fixed constant temperature cold source (8) through the pipeline The quick connector (18) on hole II (122) extends into the interior of the closed cubic test space and is connected to the injection port of the movable constant temperature cold source (7); the refrigerant outlet pipe (17) is connected by pipeline III and pipeline IV through tee II; the pipeline III is connected to the outlet of the fixed constant temperature cold source (8) through the quick connector (18) on the pipeline hole I (121); the pipeline IV extends into the interior of the closed cubic test space through the quick connector (18) on the pipeline hole II (122) and is connected to the outlet of the movable constant temperature cold source (7).

8. The device for rapidly estimating the content of block ice in permafrost according to claim 1, characterized in that: The thickness of the frozen soil sample (10) is 1 to 5 cm, and the plane size is the same as that of the fixed constant temperature cold source (8).

9. A method for using the device for rapidly estimating the content of block ice in permafrost as claimed in claim 1, comprising the following steps: (1) A test pit is excavated at the site to be tested. When the depth of the test pit reaches the permafrost layer, a sampling device is used to collect permafrost samples (10) layer by layer. The collected permafrost samples (10) are 1 to 5 cm thick and have the same plane dimensions as the fixed constant temperature cold source (8); (2) Open the cover (3), take out the movable constant temperature cold source (7), apply vaseline on the lower surface of the movable constant temperature cold source (7) and the upper surface of the fixed constant temperature cold source (8), place the frozen soil sample (10) on the fixed constant temperature cold source (8), put the movable constant temperature cold source (7) back, and inject a constant temperature liquid with a temperature of -3°C to -5°C into the interior of the movable constant temperature cold source (7) and the fixed constant temperature cold source (8) to perform constant temperature treatment on the frozen soil sample (10); ⑶ After the frozen soil sample (10) reaches a constant temperature state, the cover (3) is opened, the movable constant temperature cold source (7) is taken out, and a constant temperature liquid with a temperature of -10°C to -15°C is injected into the internal circulation of the fixed constant temperature cold source (8). The infrared imager (5) is controlled by a computer and infrared images of the frozen soil sample (10) are continuously collected until the upper surface temperature of the frozen soil sample (10) approaches the temperature of the constant temperature liquid with a temperature of -10°C to -15°C; (4) Import the infrared image of the upper surface of the collected frozen soil sample (10) into the computer, analyze the temporal variation of the upper surface temperature, interpret the block ice area in the frozen soil sample (10), determine the outline of the block ice distribution area, and calculate the block ice volume of the frozen soil sample (10) using the following formula: The volume of block ice in a single group of frozen soil samples (10) = the area of ​​block ice distribution area × the thickness of frozen soil sample (10); (5) By testing multiple sets of continuous frozen soil samples (10), the block ice areas of the multiple sets of frozen soil samples (10) obtained by interpretation are stacked in a computer, and the block ice distribution of the detection point is three-dimensionally reconstructed to understand the macroscopic structure and distribution characteristics of the block ice; (6) By stacking the block ice areas of multiple groups of frozen soil samples (10), the permafrost block ice content of the detection point is calculated according to the following formula: Lump ice content = the sum of the volume of lump ice in multiple groups of frozen soil samples (10) / the sum of the volumes of multiple groups of frozen soil samples (10).

10. The method for using the device for rapidly estimating the content of block ice in permafrost according to claim 9, characterized in that: The constant temperature liquid in step (2) and step (3) is hydraulic oil.

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