Underground sampling device for geological storage of CO2 and operation method of underground sampling device

Abstract

The invention provides an underground sampling device for geological storage of CO2 and an operation method thereof.The underground sampling device comprises a sampling pipe, a gas sampling pipe and a water sampling pipe, a partition plate is arranged in the sampling pipe and divides an inner hole of the sampling pipe into a gas sample space and a water sample space, the sampling pipe comprises a breathable side wall and a permeable side wall, the breathable side wall is communicated with the gas sample space and the outer portion of the sampling pipe, and the permeable side wall is communicated with the water sample space. The permeable side wall is communicated with the water sample space and the outside of the sampling pipe; the underground sampling device is bound on the outer side of an oil pipe and enters a wave crest on a formation hole wall to be sampled along with the oil pipe, and when the sampling pipe is used for sampling a gas sample at the wave crest on the formation hole wall, the gas sampling pipe is connected with the gas sample space; the water taking pipe is connected with the water sample space. According to the technical scheme provided by the invention, the problem that the gas sample is easy to diffuse when the sampling pipe of the sampler in the related technology is used for sampling the gas sample at the wave crest on the stratum hole wall is effectively solved.

Description

Technical Field

[0001] The present invention relates to the field of geological storage of carbon dioxide, and in particular to a method for storing carbon dioxide to obtain gaseous and liquid CO in the stratum. 2 Downhole sampling device for geological storage and operation method thereof. Background Art

[0002] The industry has a difficult problem in the field of gas and liquid sampling devices in horizontal wells of the formation after carbon dioxide is stored. The present invention aims to sample deep formations with long horizontal sections. Since the horizontal sections extend to the target formation for production, the horizontal sections of the formation are usually used as CO 2 The target layers for storage are those with good reservoir conditions and can effectively store large amounts of CO 2 In addition, the horizontal section of the formation is usually located in the deep formation, far from the surface, which is conducive to reducing CO 2 The risk of leakage. In the process of storing carbon dioxide in the horizontal section of the formation, geological conditions need to be considered, including factors such as the permeability, porosity, formation pressure, and rock type of the formation. These geological conditions have a great impact on CO 2 It has an important impact on the storage capacity and sealing stability.

[0003] Since the horizontal section of the pipeline borehole is long, the borehole wall will present a wavy shape as a whole. The gas sample entering the perforation section at the bottom of the casing in the borehole (the perforation section is to penetrate the casing to allow the water and gas sample of the formation to enter the borehole for sampling. The entire borehole outside the perforation section has casing to isolate the casing from the formation. An independent space is formed in the casing, and the casing is connected to the formation only through the holes in the perforation section) will gather at the wave crests on the formation hole wall. When the sampling tube of the sampler takes gas samples at the wave crests on the formation hole wall, the gas sample is easy to diffuse, resulting in a smaller gas sample taken from the sampler. Summary of the invention

[0004] The main purpose of the present invention is to provide a CO 2 The invention discloses a downhole sampling device for geological storage and an operation method thereof, so as to solve the problem that the gas sample is easily diffused when the sampling tube of the sampler in the related art takes the gas sample at the wave crest on the pore wall of the formation.

[0005] In order to achieve the above object, according to one aspect of the present invention, a CO 2 The downhole sampling device for geological sealing comprises: a sampling tube, a partition is arranged in the sampling tube, the partition separates the inner hole of the sampling tube into a gas sample space and a water sample space, the sampling tube comprises a gas permeable side wall and a water permeable side wall, the gas permeable side wall connects the gas sample space and the outside of the sampling tube, and the water permeable side wall connects the water sample space and the outside of the sampling tube; an air sampling tube, the air sampling tube is connected to the gas sample space; and a water sampling tube, the water sampling tube is connected to the water sample space.

[0006] Furthermore, the air-permeable side wall includes a first filter layer and an air-philic coating arranged on the outer side of the first filter layer.

[0007] Furthermore, the water-permeable side wall includes a second filter layer and a hydrophilic coating disposed outside the second filter layer.

[0008] Furthermore, the sampling tube also includes a first connecting portion connected to the first end of the air-permeable side wall and the first end of the water-permeable side wall, and the first connecting portion is plug-connected to the first end of the partition.

[0009] Furthermore, a plug hole is provided on the first connection portion, and a plug block plugged into the plug hole is provided on the first end of the partition.

[0010] Furthermore, the plug block includes a first conical block and a second conical block connected to the first conical block, the cone head of the first conical block is inserted into the insertion hole, the cone bottom of the first conical block is connected to the cone head of the second conical block, and the cone bottom of the second conical block is connected to the first end of the partition.

[0011] Furthermore, the sampling tube also includes a second connecting portion connected to the second end of the air-permeable side wall and the second end of the water-permeable side wall, and the second connecting portion is snap-connected to the second end of the partition.

[0012] Furthermore, a clamping hole is provided on the second connecting portion, and a buckle plugged into the clamping hole is provided on the second end of the partition.

[0013] Furthermore, a limiting protrusion is arranged on the inner wall of the clamping hole, and the buckle comprises a clamping shell, and a guide surface is arranged on the outer wall surface of the clamping shell. After the guide surface cooperates with the limiting protrusion, the inner wall surface of the clamping shell is clamped on the limiting protrusion.

[0014] According to another aspect of the present application, there is provided an operating method for a downhole sampling device, which is operated by using the above-mentioned downhole sampling device, and the operating method for the downhole sampling device comprises the following steps: tying the downhole sampling device to the outside of the oil pipe, and entering the downhole sampling device along the oil pipe to the wave crest on the wall of the formation hole to be sampled; collecting and storing gas samples that enter the gas sampling space of the sampling tube from the air permeable side wall of the sampling tube of the downhole sampling device; collecting and storing water samples that enter the water sampling space of the sampling tube from the water permeable side wall of the sampling tube of the downhole sampling device; taking out the gas sample in the gas sampling space through the air sampling tube, and taking out the water sample in the water sampling space through the water sampling tube.

[0015] Applying the technical solution of the present invention, CO 2The underground sampling device for geological storage includes: a sampling tube, an air sampling tube and a water sampling tube. A partition is provided in the sampling tube, and the partition separates the inner hole of the sampling tube into an air sample space and a water sample space. The sampling tube includes an air-permeable side wall and a water-permeable side wall. The air-permeable side wall connects the air sample space and the outside of the sampling tube, and the water-permeable side wall connects the water sample space and the outside of the sampling tube. The air sampling tube is connected to the air sample space. The water sampling tube is connected to the water sample space. The underground sampling device is tied to the outside of the oil pipe, and enters the wave crest on the formation hole wall to be sampled with the oil pipe. When the sampling tube takes air samples at the wave crest on the formation hole wall, there is an air sample space in the sampling tube, and the air sample can enter the air sample space from the air-permeable side wall to be collected and stored, preventing the air sample from easily diffusing. When the sampling tube takes water samples at the wave crest on the formation hole wall, there is a water sample space in the sampling tube, and the water sample can enter the water sample space from the water-permeable side wall to be collected and stored, preventing the water sample from spreading. In this way, the gas sample in the gas sample space can be taken out through the gas sampling pipe to obtain more gas samples, and the water sample in the water sample space can be taken out through the water sampling pipe to obtain more water samples, so as to facilitate sampling of gas samples and water samples on the ground. Therefore, the technical solution of the present application effectively solves the problem that the gas sample is easy to diffuse when the sampling tube of the sampler in the related art takes the gas sample at the wave crest on the formation hole wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 The CO according to the present invention is shown 2 A schematic cross-sectional view of an axial section of an embodiment of a downhole sampling device for geological storage;

[0018] Figure 2 Shows Figure 1 CO 2 A schematic cross-sectional view of a radial cross section of a downhole sampling device for geological storage;

[0019] Figure 3 Shows Figure 1 CO 2 Schematic cross-sectional view of a first connection part, a partition and a second connection part of a downhole sampling device for geological sealing.

[0020] The above drawings include the following reference numerals:

[0021] 10. Sampling tube; 11. Partition; 111. First conical block; 112. Second conical block; 113. Buckle; 114. Guide surface; 12. Gas sample space; 13. Water sample space; 14. Air-permeable side wall; 141. First filter layer; 142. Air-philic coating; 143. First end of air-permeable side wall; 144. Second end of air-permeable side wall; 15. Water-permeable side wall; 151. Second filter layer; 152. Hydrophilic coating; 153. First end of water-permeable side wall; 154. Second end of water-permeable side wall; 16. First connecting part; 161. Socket; 17. Second connecting part; 171. Clamp hole; 172. Position-limiting protrusion;

[0022] 21. Remove the air tube;

[0023] 22. Water pipe. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0026] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps set forth in these embodiments do not limit the scope of the present invention. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to the actual proportional relationship. The technology, method and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, method and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0027] The present invention provides a CO 2 Downhole sampling devices for geological storage, such as Figure 1 and Figure 2 As shown, an embodiment of the downhole sampling device includes: a sampling tube 10, an air sampling tube 21 and a water sampling tube 22. A partition 11 is provided in the sampling tube 10, and the partition 11 separates the inner hole of the sampling tube 10 into an air sample space 12 and a water sample space 13. The sampling tube 10 includes an air permeable side wall 14 and a water permeable side wall 15. The air permeable side wall 14 connects the air sample space 12 and the outside of the sampling tube 10, and the water permeable side wall 15 connects the water sample space 13 and the outside of the sampling tube 10. The air sampling tube 21 is connected to the air sample space 12.

[0028] By applying the technical solution of this embodiment, the downhole sampling device is tied to the outside of the oil pipe, and enters the peak on the formation hole wall to be sampled along with the oil pipe. When the sampling tube takes gas samples at the peak on the formation hole wall, there is a gas sample space 12 in the sampling tube 10, and the gas sample can enter the gas sample space 12 from the gas permeable side wall 14 for collection and storage, preventing the gas sample from easily diffusing. When the sampling tube takes water samples at the peak on the formation hole wall, there is a water sample space 13 in the sampling tube 10, and the water sample can enter the water sample space 13 from the water permeable side wall 15 for collection and storage, preventing the water sample from spreading. In this way, the gas sample in the gas sample space 12 can be taken out through the gas sampling tube 21, and more gas samples can be obtained. Then, the water sample in the water sample space 13 can be taken out through the water sampling tube 22, and more water samples can be obtained, so that the gas sample and the water sample can be sampled separately on the ground, and the sampling of deep formations with long horizontal sections can be completed. Therefore, the technical solution of this embodiment effectively solves the problem that the gas sample is easily diffused when the sampling tube of the sampler in the related art takes the gas sample at the wave crest on the formation hole wall.

[0029] like Figure 1 and Figure 2 As shown, the air-permeable side wall 14 includes a first filter layer 141 and an air-philic coating 142 arranged on the outside of the first filter layer 141. Gas samples can pass through the air-philic coating 142, but water samples cannot pass through. And after the gas sample passes through the air-philic coating 142 and then passes through the first filter layer 141 for filtration, it can be collected and stored in the gas sample space 12. The first filter layer 141 is preferably 1000 mesh. The air-philic coating 142 is preferably a fluorine-containing compound, which has hydrophobic and oleophobic properties due to its unique chemical structure. For example, polyparaxylene is a hydrophobic polymer material that can form a protective conformal coating. In addition, fluorinated surfactants are also used to modify air-philic surfaces to enhance their stability.

[0030] like Figure 1 and Figure 2As shown, the water-permeable side wall 15 includes a second filter layer 151 and a hydrophilic coating 152 arranged outside the second filter layer 151. The water sample can pass through the hydrophilic coating 152, but the gas sample cannot pass through. And the water sample can be collected and stored in the water sample space 13 after passing through the hydrophilic coating 152 and then filtered by the second filter layer 151. The second filter layer 151 is preferably 1000 mesh. The hydrophilic coating 152 can be polyethylene oxide or polyacrylamide or polyvinyl pyrrolidone, wherein polyacrylamide is a water-soluble polymer, and a large number of amide groups on the molecular chain make it have significant hydrophilicity. Polyvinyl pyrrolidone is an amphiphilic polymer, and due to the presence of a lactam structure in the structure, the molecular polarity is extremely large and the hydrophilicity is very strong. When polyvinyl pyrrolidone contacts water, the hydrophilic groups in the molecule connect the water molecules to the inside of the mesh cross-linked structure to form a gel.

[0031] like Figure 1 and Figure 2 As shown, in order to facilitate the reliable connection of the first end of the air-permeable side wall 14 and the first end of the water-permeable side wall 15 to the first end of the partition 11, the sampling tube 10 also includes a first connecting portion 16 connected to the first end 143 of the air-permeable side wall 14 and the first end 153 of the water-permeable side wall 15, and the first connecting portion 16 is plug-connected to the first end of the partition 11.

[0032] like Figures 1 to 3 As shown, the first connection portion 16 is provided with a plug hole 161, and the first end of the partition plate 11 is provided with an insert block plugged into the plug hole 161. The plug-in matching structure of the plug hole 161 and the insert block is simple and easy to process.

[0033] like Figures 1 to 3 As shown, the plug block includes a first tapered block 111 and a second tapered block 112 connected to the first tapered block 111, the cone head of the first tapered block 111 is inserted into the insertion hole 161, the cone bottom of the first tapered block 111 is connected to the cone head of the second tapered block 112, and the cone bottom of the second tapered block 112 is connected to the first end of the partition 11. In this way, the arrangement of the first tapered block 111 and the second tapered block 112 can increase the contact area with the hole wall of the insertion hole 161, so that the plug block can be connected in the insertion hole 161 with interference fit, so as to ensure the reliability of the plug-in connection between the first connection portion 16 and the first end of the partition 11.

[0034] like Figures 1 to 3 As shown, in order to facilitate the reliable connection of the second end 144 of the air-permeable side wall 14 and the second end 154 of the water-permeable side wall 15 with the second end of the partition 11, the sampling tube 10 also includes a second connecting portion 17 connected to the second end of the air-permeable side wall 14 and the second end 154 of the water-permeable side wall 15, and the second connecting portion 17 is snap-connected to the second end of the partition 11.

[0035] like Figures 1 to 3As shown, a clamping hole 171 is provided on the second connection portion 17, and a buckle 113 is provided on the second end of the partition plate 11 to be plugged into the clamping hole 171. The clamping matching structure of the clamping hole 171 and the buckle 113 is simple and easy to process.

[0036] like Figures 1 to 3 As shown, a limiting protrusion 172 is provided on the inner wall of the clamping hole 171, and the buckle 113 includes a clamping shell, and a guide surface 114 is provided on the outer wall surface of the clamping shell. After the guide surface 114 is guided and matched with the limiting protrusion 172, the inner wall surface of the clamping shell is clamped on the limiting protrusion 172. The setting of the guide surface 114 is convenient for guiding and matching with the limiting protrusion 172 on the one hand, and convenient for the clamping shell to be deformed and cross the limiting protrusion 172 and clamped with the limiting protrusion 172 on the other hand.

[0037] like Figure 1 and Figure 2 As shown in the figure, in order to facilitate the collection and storage of gas samples in the gas sample space 12 and the collection and storage of water samples in the water sample space 13, the length of the sampling tube 10 is greater than the length of the perforation section of the casing. In this way, the sampling tube 10 can directly collect water and gas samples from the perforation section of the casing, thereby improving the fidelity of the gas sample and more quickly discovering CO 2 Leakage time, more accurate calculation of CO 2 The amount of leakage.

[0038] One aspect of the present application provides a downhole sampling device for geological storage of carbon dioxide, including a sampling tube 10, a partition 11 is provided in the sampling tube 10, the partition 11 separates the inner hole of the sampling tube 10 into a gas sample space 12 and a water sample space 13, the sampling tube 10 includes a gas-permeable side wall 14 and a water-permeable side wall 15, the gas-permeable side wall 14 connects the gas sample space 12 and the outside of the sampling tube 10, and the water-permeable side wall 15 connects the water sample space 13 and the outside of the sampling tube 10; an air sampling pipe 21, the air sampling pipe 21 is connected to the gas sample space 12; and a water sampling pipe 22, the water sampling pipe 22 is connected to the water sample space 13. This design allows gas and water samples to be collected simultaneously when monitoring geological storage of carbon dioxide, effectively improving the sampling efficiency, and is suitable for various downhole operation scenarios such as geological research, oil and gas field development, and carbon capture and storage.

[0039] The implementation of this downhole sampling device has a significant effect. It can not only save a lot of time and reduce the complexity of downhole operations, but also ensure the purity and accuracy of gas and water samples during the collection process, avoiding the risk of cross-contamination. In the carbon dioxide geological storage project, this device can monitor the storage effect in real time, evaluate whether carbon dioxide has leaked, and the pressure and temperature changes of the storage layer, and provide data support for the safety and effectiveness of geological storage. In the development of oil and gas fields, it can help geological engineers understand the properties of underground fluids and provide a basis for optimizing mining strategies. In addition, this device is also suitable for hydrogeological surveys. By collecting deep groundwater samples and analyzing water quality and groundwater resources, it is of great value to the protection and utilization of water resources.

[0040] Furthermore, the air-permeable side wall 14 includes a first filter layer 141 and an air-philic coating 142 disposed outside the first filter layer 141. The first filter layer can effectively filter out impurities entering the gas sample space to ensure the purity of the gas sample, while the air-philic coating can enhance the gas adsorption and transmission efficiency, and is particularly suitable for environments with low gas content, such as deep geological exploration, mine ventilation detection, etc.

[0041] This design of the breathable side wall greatly improves the sampling capability in low gas content environments, ensuring that sufficient gas samples are collected for accurate analysis even when the gas concentration is very low. The use of aerosol-friendly coatings can significantly increase the flow rate of gas in the sampling tube and reduce the residence time of gas in the pores, which is crucial for timely sampling in a rapidly changing underground environment. In mine ventilation testing, this device can monitor the concentration of toxic and harmful gases, which is of great significance for protecting the lives of miners and the safety of mine production.

[0042] Furthermore, the permeable side wall 15 includes a second filter layer 151 and a hydrophilic coating 152 disposed outside the second filter layer 151. The second filter layer can effectively filter solid particles in the water sample to ensure the purity of the water sample, while the hydrophilic coating can increase the collection speed of the water sample, which is suitable for scenes such as groundwater monitoring and hydrogeological surveys, and ensures the accuracy of water sample analysis.

[0043] The second filter layer and hydrophilic coating of the permeable side wall together ensure the high purity and collection efficiency of water samples, which is particularly important for groundwater monitoring. In hydrogeological surveys, water sample analysis can reveal groundwater flow direction, water quality changes and potential pollution sources, providing a scientific basis for groundwater protection and water resource management. The use of hydrophilic coating enables water samples to maintain good collection effects even at high flow rates, which is suitable for downhole water sample monitoring after hydraulic fracturing and water sample analysis of deep-sea oil and gas wells.

[0044] Furthermore, the sampling tube 10 further includes a first connection portion 16 connected to the first end 143 of the air-permeable side wall 14 and the first end 153 of the water-permeable side wall 15, and the first connection portion 16 is plug-connected to the first end of the partition 11. This plug-in connection method not only simplifies the assembly process of the sampling tube, but also ensures the sealing of the internal space of the sampling tube, and is suitable for underground working environments that require frequent disassembly and assembly, such as geological exploration, underground equipment maintenance, etc.

[0045] The implementation of plug-in connection technology has greatly improved the flexibility and adaptability of downhole sampling devices. In geological exploration projects, it is often necessary to adjust the configuration of sampling tubes according to different geological layers and monitoring requirements. This quick plug-in connection method can significantly reduce the operation preparation time and improve work efficiency. At the same time, good sealing performance ensures the accuracy of sampling in high-pressure and high-flow downhole environments and reduces the risk of sample contamination.

[0046] Furthermore, a plug hole 161 is provided on the first connection portion 16, and a plug block plugged into the plug hole 161 is provided on the first end of the partition 11. The coordinated use of the plug hole and the plug block makes the connection between the partition and the sampling tube more stable, avoiding sample mixing due to vibration or pressure changes during downhole operations, and is suitable for downhole environments with complex geological conditions and large pressure changes, such as oil and gas wells, deep water wells, etc.

[0047] The use of the jack and the plug ensures that the structure of the sampling tube remains stable even in extreme downhole environments, avoiding the influence of sample mixing on the analysis results. This technology is particularly suitable for monitoring oil and gas wells and deepwater wells. These environments are often accompanied by high temperature, high pressure and complex geological structures, which place extremely high demands on the stability of the sampling equipment. By improving the connection strength between the partition and the sampling tube, the risk of downhole operations can be effectively reduced and the reliability and authenticity of the sampling data can be ensured.

[0048] Furthermore, the plug block includes a first conical block 111 and a second conical block 112 connected to the first conical block 111, the cone head of the first conical block 111 is inserted into the insertion hole 161, the cone bottom of the first conical block 111 is connected to the cone head of the second conical block 112, and the cone bottom of the second conical block 112 is connected to the first end of the partition 11. The use of the conical block makes the plug-in process smoother, and the conical structure can enhance the sealing effect of the connection, which is suitable for downhole sampling operations that require high sealing, such as high-pressure oil and gas wells, carbon dioxide storage monitoring, etc.

[0049] The design of the conical plug not only optimizes the structural connection inside the sampling tube, but also improves the overall sealing and pressure resistance of the sampling tube. In the sampling operation of high-pressure oil and gas wells, this design can effectively resist the downhole high-pressure environment, prevent gas leakage, and ensure the safety of sampling work. In the carbon dioxide storage monitoring, the high sealing of the conical plug can ensure the accuracy of the monitoring data, which plays an important role in evaluating the carbon dioxide storage effect and monitoring the stability of the storage layer.

[0050] Furthermore, the sampling tube 10 further includes a second connection portion 17 connected to the second end 144 of the air-permeable side wall 14 and the second end 154 of the water-permeable side wall 15, and the second connection portion 17 is snap-connected to the second end of the partition 11. The snap-connection method is not only convenient for assembly, but also ensures the structural stability of the sampling tube during downhole operations, and is suitable for downhole operations that require rapid deployment and recovery, such as emergency geological disaster monitoring, rapid sampling of oil and gas wells, etc.

[0051] The application of snap-on connection technology makes the assembly and disassembly of sampling tubes more convenient, significantly improving the response speed of underground operations. In emergency geological disaster monitoring, this rapid deployment capability can collect gas and water samples from the disaster-affected strata in a timely manner, which is of great significance for disaster warning and post-disaster analysis. In the rapid sampling of oil and gas wells, the snap-on connection method can quickly adjust the sampling position, improving the flexibility and efficiency of sampling, which is crucial for real-time monitoring of underground environmental changes and adjusting mining strategies.

[0052] Furthermore, a limiting protrusion 172 is provided on the inner wall of the clamping hole 171, and the buckle 113 includes a clamping shell, and the outer wall surface of the clamping shell is provided with a guide surface 114. After the guide surface 114 is guided and matched with the limiting protrusion 172, the inner wall surface of the clamping shell is clamped on the limiting protrusion 172. The combination of the limiting protrusion and the guide surface not only ensures the smooth progress of the clamping process, but also enhances the pressure resistance of the sampling tube, which is suitable for downhole operation environments with high pressure and high flow rate, such as deep-sea oil and gas exploration, high-pressure hydraulic fracturing monitoring, etc.

[0053] The innovative design of the limiting protrusion and the guide surface greatly improves the operational safety of the sampling tube in high-pressure and high-flow rate environments. In deep-sea oil and gas exploration, this design can effectively resist the high pressure of the deep sea, ensure the integrity of the internal structure of the sampling tube and the purity of the sample, and improve the efficiency and safety of deep-sea oil and gas resource development. In high-pressure hydraulic fracturing monitoring, the sampling tube needs to withstand extremely high water pressure and flow rate. This design can ensure the stability and reliability of the sampling tube during the monitoring process, which is of great value for optimizing the fracturing process and evaluating the fracturing effect.

[0054] The present application also provides an operating method of a downhole sampling device, and the operating method of the downhole sampling device is operated by the above-mentioned downhole sampling device. The operating method of the downhole sampling device includes the following steps: tying the downhole sampling device to the outside of the oil pipe, and entering the wave crest on the formation hole wall to be sampled along the oil pipe; collecting and storing the gas sample that enters the gas sample space 12 of the sampling tube 10 from the air-permeable side wall of the sampling tube 10 of the downhole sampling device; collecting and storing the water sample that enters the water sample space 13 of the sampling tube 10 from the water-permeable side wall of the sampling tube 10 of the downhole sampling device; taking out the gas sample in the gas sample space 12 through the gas sampling tube 21, and taking out the water sample in the water sample space 13 through the water sampling tube 22. Because the above-mentioned downhole sampling device can solve the problem that the gas sample is easy to diffuse when the sampling tube of the sampler in the related art takes the gas sample at the wave crest on the formation hole wall. The operating method of the downhole sampling device is operated by the above-mentioned downhole sampling device, which can also solve the same technical problem.

[0055] Another aspect of the present application provides an operation method of a downhole sampling device, which is operated by the above-mentioned downhole sampling device, and the operation method includes the following steps: tying the downhole sampling device to the outside of the oil pipe, and entering the wave crest on the wall of the formation hole to be sampled along the oil pipe; collecting and storing the gas sample that enters the gas sample space 12 of the sampling pipe 10 from the gas permeable side wall of the sampling pipe 10; collecting and storing the water sample that enters the water sample space 13 of the sampling pipe 10 from the water permeable side wall of the sampling pipe 10; taking out the gas sample in the gas sample space 12 through the gas sampling pipe 21, and taking out the water sample in the water sample space 13 through the water sampling pipe 22. This operation method not only simplifies the sampling process, but also improves the sampling accuracy and efficiency, and is particularly suitable for scenes such as carbon dioxide geological storage monitoring, oil and gas field development, and groundwater monitoring, and provides a powerful tool for the research of geology and environmental sciences.

[0056] The operation method of the downhole sampling device is simple and clear, and it is easy for on-site operators to master and use, which significantly improves the efficiency and success rate of downhole sampling operations. In carbon dioxide geological storage projects, this method can monitor the status of the carbon dioxide storage layer in real time and evaluate the storage effect. In oil and gas field development, this method can quickly collect formation fluid samples, provide geological engineers with instant fluid property data, optimize mining plans, and improve resource recovery rates. In groundwater monitoring, it can collect formation water samples in real time and analyze water quality changes, which is of great significance for the protection and rational use of water resources. In addition, this device and operation method are also suitable for other downhole operations, such as earthquake precursor monitoring, mine ventilation detection, etc., and have broad application prospects and market potential.

[0057] Based on an in-depth analysis of Document 1, combined with the examples and drawings in Document 2, we are able to carefully describe and understand the design details and operation process of this innovative downhole sampling device for geological storage of carbon dioxide. The following is a detailed interpretation of the drawings and examples in Document 2:

[0058] Figure 1 The main structure of the sampling tube 10 is shown, including the gas sample space 12 and the water sample space 13 therein, which are separated by a partition 11. The provision of the partition 11 ensures the independent collection of gas and liquid samples and avoids mutual contamination. In the figure, we notice the presence of a breathable side wall 14 and a water permeable side wall 15, which are respectively designed with a first filter layer 141 and a second filter layer 151, which can effectively block impurities and ensure the purity of the sample. The outside of the breathable side wall 14 is coated with an air-philic coating 142, while the outside of the water-permeable side wall 15 is coated with a hydrophilic coating 152. These coatings increase the affinity of the sampling device to carbon dioxide gas and groundwater, thereby enhancing the sampling efficiency.

[0059] Figure 2 The structure of the first connection part 16 and the second connection part 17 of the sampling tube 10 and how they are connected to the partition 11 are further shown in detail. The first connection part 16 is designed with a plug hole 161, and the first end of the partition 11 is equipped with a plug block, which is composed of a first conical block 111 and a second conical block 112. This design makes the insertion and fixation of the partition 11 more stable, and also facilitates disassembly and maintenance. The second connection part 17 is connected by a snap-on connection through a snap hole 171 and a snap buckle 113 on the second end of the partition 11, wherein the guide surface 114 provided on the outer wall of the snap shell can be guided and matched with the limiting protrusion 172 on the inner wall of the snap hole 171, and finally the inner wall of the snap shell is snapped on the limiting protrusion 172, ensuring the reliability of the structure and the sealing of the sample.

[0060] Figure 3 The use of the sampling device in combination with the oil pipe in actual operation is depicted. The sampling pipe 10 is tied to the outside of the oil pipe and enters the wave crest on the pore wall of the formation along the oil pipe. This design makes full use of the existing equipment in oil field operations, greatly simplifies the sampling process, and reduces the difficulty of operation. In the formation, carbon dioxide gas enters the gas sample space 12 through the gas permeable side wall 14 and the first filter layer 141, while groundwater enters the water sample space 13 through the water permeable side wall 15 and the second filter layer 151. Subsequently, the gas sample and water sample can be taken out through the gas sampling pipe 21 and the water sampling pipe 22 for subsequent analysis.

[0061] The design of this sampling device, combined with its operating method, significantly improves the efficiency and accuracy of sampling in underground environments such as carbon dioxide geological storage. By separating the collection process of gas and water samples, cross-contamination between samples is avoided and the purity of the samples is ensured. The use of the first filter layer 141 and the second filter layer 151 effectively filters impurities in the formation and further improves the sample quality. The addition of the air-philic coating 142 and the hydrophilic coating 152 enhances the affinity between the device and the target sample and improves the collection efficiency. In addition, the combined use of the sampling tube 10 and the oil pipe simplifies the operating process and reduces the sampling cost. The overall design embodies innovation and practicality, is suitable for a variety of underground environments, and has broad application prospects.

[0062] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the devices or elements referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention. The directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0063] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0064] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0065] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A downhole sampling device for CO2 geological storage, characterized in that: include: A sampling tube (10), wherein a partition (11) is arranged inside the sampling tube (10), wherein the partition (11) separates the inner hole of the sampling tube (10) into a gas sample space (12) and a water sample space (13), wherein the sampling tube (10) comprises a gas permeable side wall (14) and a water permeable side wall (15), wherein the gas permeable side wall (14) is connected to the gas sample space (12) and the outside of the sampling tube (10), and the water permeable side wall (15) is connected to the water sample space (13) and the outside of the sampling tube (10); An air extraction pipe (21), the air extraction pipe (21) being connected to the air sample space (12); A water intake pipe (22), wherein the water intake pipe (22) is connected to the water sample space (13).

2. The downhole sampling device according to claim 1, characterized in that: The air-permeable side wall (14) comprises a first filter layer (141) and an air-philic coating (142) arranged on the outside of the first filter layer (141).

3. The downhole sampling device according to claim 1, characterized in that: The water-permeable side wall (15) comprises a second filter layer (151) and a hydrophilic coating (152) arranged on the outside of the second filter layer (151).

4. The downhole sampling device according to claim 1, characterized in that: The sampling tube (10) further comprises a first connecting portion (16) connected to the first end (143) of the air-permeable side wall (14) and the first end (153) of the water-permeable side wall (15), and the first connecting portion (16) is plug-connected to the first end of the partition (11).

5. The downhole sampling device according to claim 4, characterized in that: The first connecting portion (16) is provided with a plug hole (161), and the first end of the partition plate (11) is provided with an insert block which is plugged into the plug hole (161).

6. The downhole sampling device according to claim 5, characterized in that: The insert block comprises a first conical block (111) and a second conical block (112) connected to the first conical block (111); the conical head of the first conical block (111) is inserted into the insertion hole (161); the conical bottom of the first conical block (111) is connected to the conical head of the second conical block (112); and the conical bottom of the second conical block (112) is connected to the first end of the partition (11).

7. The downhole sampling device according to claim 1, characterized in that: The sampling tube (10) further comprises a second connecting portion (17) connected to the second end (144) of the air-permeable side wall (14) and the second end (154) of the water-permeable side wall (15), and the second connecting portion (17) is snap-connected to the second end of the partition (11).

8. The downhole sampling device according to claim 7, characterized in that: The second connecting portion (17) is provided with a locking hole (171), and the second end of the partition plate (11) is provided with a locking buckle (113) plugged into the locking hole (171).

9. The downhole sampling device according to claim 8, characterized in that: A limiting protrusion (172) is arranged on the inner wall of the clamping hole (171), and the buckle (113) comprises a clamping shell, and a guide surface (114) is arranged on the outer wall surface of the clamping shell. After the guide surface (114) is guided and matched with the limiting protrusion (172), the inner wall surface of the clamping shell is clamped on the limiting protrusion (172).

10. A method for operating a downhole sampling device, characterized in that: The downhole sampling device according to any one of claims 1 to 9 is used for operation, and the operation method of the downhole sampling device comprises the following steps: Tie the downhole sampling device to the outside of the oil pipe and follow the oil pipe into the wave crest on the wall of the formation to be sampled; Collecting and storing gas samples that enter the gas sample space (12) of the sampling tube (10) from the gas permeable side wall of the sampling tube (10) of the downhole sampling device; Collecting and storing water samples that enter the water sample space (13) of the sampling tube (10) from the water-permeable side wall of the sampling tube (10) of the downhole sampling device; The gas sample in the gas sample space (12) is taken out through the gas sampling pipe (21), and the water sample in the water sample space (13) is taken out through the water sampling pipe (22).

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