Methods for Pressure-Maintaining and Fidelity-Enhancing Sampling Operations Inside the Combustible Ice Accumulation Experiment Chamber

Abstract

This invention relates to a method for pressure-maintaining and high-fidelity sampling within a combustible ice reservoir testing chamber. Utilizing the chamber-penetrating function of a dry-wet conversion chamber and the sampling function of an insertion-type sampling tool, it provides a standardized and highly stable pressure-maintaining and high-fidelity sampling process and method. This method effectively obtains complete formation reservoir samples within the high-pressure testing chamber. The samples can then be delivered to a dedicated slicing and scanning device for slicing and imaging using a specific pressure-maintaining and high-fidelity delivery method, resulting in highly visualized assessments of the formation reservoir formation effect.

Description

Technical Field

[0001] This invention relates to the field of combustible ice accumulation test technology, and in particular to a method for pressure-maintaining and high-fidelity sampling operation in a combustible ice accumulation test chamber. Background Technology

[0002] Methane hydrate accumulation experiments are an important experimental method for systematically studying the accumulation mechanism of methane hydrate. Currently, relatively systematic experiments on the accumulation mechanism of methane hydrate have been conducted both domestically and internationally. However, due to the need to establish a high-pressure, low-temperature experimental environment, these experiments are usually carried out inside pressure vessels. Because of their sealed nature, the experimental formation is essentially a "black box," making it impossible to obtain accurate and clearly visible assessment results of the accumulation effect. Currently, the commonly used technique is to invert the accumulation state of the formation through resistivity measurements. However, due to the large number of sensors and other equipment interspersed within the formation, and its low resistivity, obtaining the true resistivity of the formation is extremely difficult. Researchers find it very difficult to filter and process the measured resistivity results to obtain accurate formation conditions.

[0003] To address the existing technical bottlenecks in combustible ice accumulation experiments, a pressure-maintaining and high-fidelity sampling procedure for combustible ice accumulation experiments and other similar experiments is proposed. The aim is to achieve pressure-maintaining and high-fidelity sampling and testing of accumulation samples in a high-pressure test chamber through a specific operating mode, and then obtain highly visualized stratigraphic tomography images through certain slicing scanning techniques, thereby obtaining more realistic assessment conclusions on the accumulation effect. Summary of the Invention

[0004] To address the shortcomings of existing production technologies, the applicant provides a method for pressure-maintaining and high-fidelity sampling within a combustible ice reservoir test chamber. This method involves sending a sampling device into the combustible ice reservoir test chamber through a series of standard operating procedures, obtaining formation reservoir samples using an insertion method, sending the reservoir samples out of the test chamber through a dedicated channel, and finally sending the formation reservoir samples into a slice scanning device for scanning and imaging using a dedicated pressure-maintaining cylinder.

[0005] The technical solution adopted in this invention is as follows:

[0006] A method for pressure-maintaining and high-fidelity sampling in a combustible ice accumulation test chamber includes the following steps:

[0007] Step 1: Open the outer door of the wet-dry conversion chamber and install the sampling device on the track inside the wet-dry conversion chamber;

[0008] Step 2: Close the outer door of the dry-wet conversion chamber, inject water and pressurize the dry-wet conversion chamber until the pressure is balanced with that of the combustible ice accumulation test chamber, and then open the inner door of the dry-wet conversion chamber.

[0009] Step 3: Use the track to send the sampling device into the combustible ice accumulation test chamber, adjust the track's progress, precisely control the sampling device's placement point, and prepare for the sampling operation.

[0010] Step 4: Activate the sampling device deployment mechanism to change the sampling device from a horizontal translational posture to an upright sampling posture, and fine-tune the position of the sampling device through the pressure-resistant camera to align it with the center of the isolation cylinder at the sampling point to prevent it from hitting the wall when inserted.

[0011] Step 5: Activate the rotating propulsion mechanism inside the sampling device to push the sampling rod downwards, and the sample cylinder inside the sampling rod will also perform the downward insertion action;

[0012] Step 6: During the insertion process, monitor the alignment of the sampling rod with the isolation cylinder inside the chamber and make timely adjustments to ensure that the sampling rod can be smoothly and without collision inserted into the isolation cylinder. Rely on the constraint of the isolation cylinder to control the shaking of the sampling rod during the insertion process and ensure the integrity of the sample after entering the sample cylinder.

[0013] Step 7: When the predetermined insertion depth is reached, stop the insertion action, reverse the rotation propulsion mechanism, and lift the sample extraction rod and sample cylinder together until they leave the isolation cylinder;

[0014] Step 8: After lifting is complete, reverse the unfolding mechanism to flip the sampling device from the upright position to the horizontal position;

[0015] Step 9: Push the track to its full length, push the sampling rod of the sampling device into the delivery channel, and prepare for sample delivery;

[0016] Step 10: Check that the three high-pressure sealing ball valves in the pressure-maintaining and authentic delivery device are closed, and inject water into the pressure-maintaining and authentic delivery device to pressurize it until it is balanced with the pressure in the combustible ice accumulation test chamber;

[0017] Step 11: Open the two high-pressure sealing ball valves inside the pressure-maintaining and fidelity-preserving delivery device to connect the pressure-maintaining and fidelity-preserving delivery device with the combustible ice accumulation test chamber;

[0018] Step 12: Activate the ejection device at the top of the sampling device to push the sample tube from the sampling rod into the pressure-holding and fidelity delivery device, and then remove the sampling device.

[0019] Step 13: Close all valves of the pressure holding and fidelity delivery device, disconnect the external flange, and connect the pressure holding and fidelity delivery device to the matching slice scanning mechanism to achieve scanning imaging;

[0020] Step 14: Done.

[0021] As a further improvement to the above technical solution:

[0022] The dry-wet conversion chamber and the pressure-preserving and high-fidelity delivery device are at the same height.

[0023] The central axes of the dry-wet conversion chamber and the pressure-preserving and high-fidelity delivery device are both perpendicular to the central axis of the combustible ice accumulation test chamber.

[0024] The dry-wet conversion chamber and the combustible ice accumulation test chamber are integrated into one structure.

[0025] The beneficial effects of this invention are as follows:

[0026] This invention features a compact and rational structure and is easy to operate. Through the coordinated operation of the dry-wet conversion chamber, sampling device, unfolding mechanism, and pressure-preserving and high-fidelity delivery device, sampling can be easily completed. It overcomes the black box nature of the pressure test chamber and enables the smooth delivery of combustible ice accumulation samples under pressure-preserving and high-fidelity conditions. Combined with subsequent slice scanning imaging technology, it upgrades the original resistivity imaging technology to a truly visual imaging technology, improving accuracy and reducing technical difficulty in assessing accumulation effects. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the present invention.

[0028] Figure 2 This is a schematic diagram of the sampling posture of the present invention.

[0029] Figure 3 This is a schematic diagram of the operation of the sampling device of the present invention.

[0030] Figure 4 This is a schematic diagram of the sampling device of the present invention.

[0031] Figure 5 This is a schematic diagram of the sampling chamber structure of the present invention.

[0032] Figure 6 This is a schematic diagram of the workflow of the present invention.

[0033] The components include: 1. Combustible ice accumulation test chamber; 2. Dry-wet conversion chamber; 3. Translation track; 4. Sampling device; 5. Deployment mechanism; 6. Pressure-holding and high-fidelity delivery device; 7. No. 1 high-pressure sealing valve; 8. No. 2 high-pressure sealing valve; 9. No. 3 high-pressure sealing valve; 10. Pressure-resistant camera; 11. Outer hatch; 12. Inner hatch; 13. External flange; 14. Accumulation strata.

[0034] 401. Frame; 402. Ejection device; 403. Guide plate; 404. Sampling rod; 405. Ejection tube; 406. Rotary propulsion mechanism; 407. Isolation tube; 408. Sample tube. Detailed Implementation

[0035] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0036] like Figures 1-6 As shown, the pressure-maintaining and high-fidelity sampling method inside the combustible ice accumulation test chamber in this embodiment includes the following steps:

[0037] Step 1: Open the outer hatch 11 of the wet-dry conversion chamber 2 and install the sampling device 4 on the track inside the wet-dry conversion chamber 2;

[0038] Step 2: Close the outer hatch 11 of the wet-dry conversion chamber 2, inject water and pressurize the wet-dry conversion chamber 2 until the pressure reaches equilibrium with that of the combustible ice accumulation test chamber 1, and open the inner hatch 12 of the wet-dry conversion chamber 2.

[0039] Step 3: Use the track to send the sampling device 4 into the combustible ice accumulation test chamber 1, adjust the progress of the track, and precisely control the placement point of the sampling device 4 to prepare for the sampling operation.

[0040] Step 4: Activate the sampling device 4 unfolding mechanism 5 to change the sampling device 4 from a horizontal translation posture to an upright sampling posture, and finely adjust the position of the sampling device 4 through the pressure-resistant camera 10 to align it with the center of the isolation cylinder 407 at the sampling point to prevent it from hitting the wall when it is inserted.

[0041] Step 5: Activate the rotating propulsion mechanism 406 inside the sampling device 4 to push the sampling rod 404 downward, and the sample cylinder 408 inside the sampling rod 404 will also perform the downward insertion action.

[0042] Step 6: During the insertion process, monitor the alignment of the sampling rod 404 with the isolation cylinder 407 inside the chamber and make timely adjustments to ensure that the sampling rod 404 can be smoothly and without collision inserted into the isolation cylinder 407. Rely on the constraint of the isolation cylinder 407 to control the shaking of the sampling rod 404 during the insertion process and ensure the integrity of the sample after entering the sample cylinder 408.

[0043] Step 7: When the predetermined insertion depth is reached, stop the insertion action, reverse the rotation propulsion mechanism 406, and lift the upper extraction rod 404 and sample cylinder 408 together until they leave the isolation cylinder 407.

[0044] Step 8: After the lifting is complete, start the unfolding mechanism 5 in the reverse direction to flip the sampling device 4 from the upright position to the horizontal position;

[0045] Step 9: Push the track to its full length, push the sampling rod 404 of the sampling device 4 into the delivery channel, and prepare for sample delivery;

[0046] Step 10: Check that the three high-pressure sealing ball valves inside the pressure-maintaining and authentic delivery device 6 are closed, and inject water into the pressure-maintaining and authentic delivery device 6 to pressurize it until it is balanced with the pressure inside the combustible ice storage test chamber 1;

[0047] Step 11: Open the two high-pressure sealing ball valves inside the pressure-maintaining and fidelity-preserving delivery device 6 to connect the pressure-maintaining and fidelity-preserving delivery device 6 with the combustible ice accumulation test chamber 1;

[0048] Step 12: Activate the ejection device 402 on the upper part of the sampling device 4 to push the sample cylinder 408 from the sampling rod 404 into the pressure-holding and fidelity delivery device 6, and then remove the sampling device 4.

[0049] Step 13: Close all valves of the pressure holding and fidelity delivery device 6, disconnect the external flange 13, and connect the pressure holding and fidelity delivery device 6 to the matching slice scanning mechanism to achieve scanning imaging;

[0050] Step 14: Done.

[0051] The dry-wet conversion chamber 2 and the pressure-preserving and high-fidelity delivery device 6 are at the same height.

[0052] The central axes of the dry-wet conversion chamber 2 and the pressure-preserving and high-fidelity delivery device 6 are both perpendicular to the central axis of the combustible ice accumulation test chamber 1.

[0053] The dry-wet conversion chamber 2 and the combustible ice accumulation test chamber 1 are integrated into one structure.

[0054] like Figure 1 As shown, the present invention also includes a pressure-maintaining and high-fidelity sampling system inside the combustible ice accumulation test chamber. The specific structure is as follows: it includes a combustible ice accumulation test chamber 1, the bottom of which is the accumulation stratum 14. Symmetrical holes are opened on the chamber wall of the combustible ice accumulation test chamber 1 above the accumulation stratum 14. A dry-wet conversion chamber 2 and a pressure-maintaining and high-fidelity delivery device 6 are respectively installed outside the two holes. One end of the dry-wet conversion chamber 2 is an inner door 12, and the other end is an outer door 11. The dry-wet conversion chamber 2 is equipped with horizontally spaced tracks that are fixed. A translation track 3 is installed above the horizontal tracks. A sampling device 4 is installed on the translation track 3. An unfolding mechanism 5 is installed at the bottom of the sampling device 4. Through the action of the unfolding mechanism 5, the sampling device 4 can be horizontal on the translation track 3. As the translation track 3 slides, it can also rotate 90 degrees to a vertical state. A pressure-resistant camera 10 is installed at the bottom of the unfolding mechanism 5.

[0055] The sampling device 4 has the following structure: a frame 401, a rotary propulsion mechanism 406 installed at the bottom of the frame 401, an ejector tube 405 installed in the middle of the frame 401, the top of the ejector tube 405 connected to the frame 401 through a guide plate 403, a sampling rod 404 installed at the bottom of the ejector tube 405 after passing through the rotary propulsion mechanism 406, an ejection device 402 installed inside the ejector tube 405, the sampling rod 404 can penetrate into the reservoir 14, a sample tube 408 is concentrically installed inside the sampling rod 404, the outer circumference of the sampling rod 404 is limited by an isolation tube 407, and it can be inserted into the reservoir 14.

[0056] The structure of the pressure-maintaining and high-fidelity delivery device 6 is as follows: it includes a pipe connected to the combustible ice accumulation test chamber 1, the head of the pipe is connected to the high-fidelity cylinder through an external flange 13, a first high-pressure sealing valve 7 is installed inside the pipe, and a second high-pressure sealing valve 8 and a third high-pressure sealing valve 9 are installed at both ends of the high-fidelity cylinder, respectively.

[0057] The installation and operation steps of this invention are as follows:

[0058] Step 1: Under the condition that the inner door 12 of the wet-dry conversion chamber 2 is closed in a good condition, open the outer door 11 of the wet-dry conversion chamber, place the sampling device 4 together with the translation track 3 on the track inside the wet-dry conversion chamber 2, and check the sliding performance of the translation track 3.

[0059] Step 2: Close the outer hatch 11 of the wet-dry conversion chamber 2, inject water into the wet-dry conversion chamber 2 and pressurize it. When the pressure in the wet-dry conversion chamber 2 is balanced with the pressure in the combustible ice accumulation test chamber 1, stop injecting water and pressurizing, and open the inner hatch 12.

[0060] Step 3: Use the matching hydraulic cylinder to push the translation track 3 forward, and drive the sampling device 4 into the combustible ice accumulation test chamber 1. Fine-tune the progress of the translation track 3 to ensure that the sampling device 4 is above the predetermined sampling point.

[0061] Step 4: Drive the unfolding mechanism 5 to rotate, change the sampling device 4 from a horizontal translational posture to an upright sampling posture, and monitor the cabin image data in real time through the pressure-resistant camera 10, fine-tune the sampling device 4, align it with the center of the isolation cylinder 407 at the sampling point to prevent it from hitting the wall when it is inserted.

[0062] Step 5: Activate the rotating propulsion mechanism 406 inside the sampling device 4 to push the sampling rod 404 downward, and the sample cylinder 408 inside the sampling rod 404 will also perform the downward insertion action.

[0063] Step Six: During the insertion process, closely monitor the alignment of the sampling rod 404 with the isolation cylinder 407 inside the chamber and make timely adjustments to ensure that the sampling rod 404 can be smoothly and without collision inserted into the isolation cylinder 407. Rely on the constraint of the isolation cylinder 407 to control the shaking and bending deformation of the sampling rod 404 during the insertion process, so as to ensure the integrity of the formation sample after entering the sample cylinder 408.

[0064] Step 7: When the predetermined insertion depth is reached, stop the insertion action, reverse the rotational propulsion mechanism 406, and lift the sample extraction rod 404 and the connected sample cylinder 408 together until they leave the isolation cylinder 407.

[0065] Step 8: After the sampling device 4 is raised to the position, the unfolding mechanism 5 is activated in the reverse direction to flip the sampling device 4 from the upright position to the horizontal position, ready to send out the formation sample.

[0066] Step 9: Push the translation track 3 to its full length, push the sampling rod 404 of the sampling device 4 into the delivery channel, and prepare for sample delivery;

[0067] Step 10: Check that the three high-pressure sealing valves inside the pressure-maintaining and authentic delivery device 6 are closed to the sealed state, and inject water into the pressure-maintaining and authentic delivery device 6 to pressurize it until it is balanced with the pressure inside the combustible ice accumulation test chamber 1;

[0068] Step 11: Open the two high-pressure sealing valves inside the pressure-maintaining and fidelity-preserving delivery device 6 to connect the pressure-maintaining and fidelity-preserving delivery device 6 with the combustible ice accumulation test chamber 1;

[0069] Step 12: Activate the ejection device 402 on the upper part of the sampling device 4 to push the sample cylinder 408 from the sampling rod 404 into the pressure-holding and fidelity delivery device 6, and then remove the sampling device 4.

[0070] Step 13: Close all valves of the pressure-holding and high-fidelity delivery device 6, disconnect the external flange 13, and connect the pressure-holding and high-fidelity delivery device 6 to the matching slicing and scanning mechanism to achieve scanning imaging. At this point, the operation process and method of pressure-holding and high-fidelity sampling in the combustible ice accumulation test chamber are completed.

[0071] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. A method for pressure-maintaining and high-fidelity sampling operation inside a combustible ice accumulation test chamber, characterized in that: The system is used in the pressure-maintaining and high-fidelity sampling system inside the combustible ice accumulation test chamber. The system structure is as follows: it includes a combustible ice accumulation test chamber (1), the bottom of which is the accumulation stratum (14). Symmetrical holes are opened on the walls of the combustible ice accumulation test chamber (1) above the accumulation stratum (14). A dry-wet conversion chamber (2) and a pressure-maintaining and high-fidelity delivery device (6) are installed on the outside of the two holes respectively. One end of the dry-wet conversion chamber (2) is an inner door (12), and the other end is an outer door (11). (2) is equipped with a horizontal track with intervals. The horizontal track is fixed. A translation track (3) is installed above the horizontal track. A sampling device (4) is installed on the translation track (3). An unfolding mechanism (5) is installed at the bottom of the sampling device (4). Through the action of the unfolding mechanism (5), the sampling device (4) can be horizontal on the translation track (3). As the translation track (3) slides, it can also rotate 90 degrees to become vertical. A pressure-resistant camera (10) is installed at the bottom of the unfolding mechanism (5). The sampling device (4) has the following structure: a frame (401), a rotary propulsion mechanism (406) installed at the bottom of the frame (401), a catapult (405) installed in the middle of the frame (401), the top of the catapult (405) connected to the frame (401) through a guide plate (403), a sampling rod (404) installed at the bottom of the catapult (405) after passing through the rotary propulsion mechanism (406), a catapult device (402) installed inside the catapult (405), the sampling rod (404) can penetrate into the reservoir (14), a sample tube (408) is concentrically installed inside the sampling rod (404), the outer circumference of the sampling rod (404) is limited by an isolation tube (407), and it can be inserted into the reservoir (14). The structure of the pressure-maintaining and fidelity-conveying delivery device (6) is as follows: it includes a pipe connected to the combustible ice storage test chamber (1), the head of the pipe is connected to the fidelity cylinder through an external flange (13), a first high-pressure sealing valve (7) is installed inside the pipe, and a second high-pressure sealing valve (8) and a third high-pressure sealing valve (9) are installed at both ends of the fidelity cylinder respectively. The work method includes the following steps: Step 1: Open the outer hatch (11) of the wet-dry conversion chamber (2) and install the sampling device (4) on the track inside the wet-dry conversion chamber (2); Step 2: Close the outer door (11) of the wet-dry conversion chamber (2), inject water into the wet-dry conversion chamber (2) and pressurize it until the pressure reaches equilibrium with that of the combustible ice reservoir test chamber (1), and open the inner door (12) of the wet-dry conversion chamber (2). Step 3: Use the track to send the sampling device (4) into the combustible ice accumulation test chamber (1), adjust the track's progress, precisely control the placement point of the sampling device (4), and prepare for the sampling operation. Step 4: Activate the sampling device (4) unfolding mechanism to change the sampling device (4) from a horizontal translation posture to an upright sampling posture, and fine-tune the position of the sampling device (4) through the pressure-resistant camera (10) to align it with the center of the isolation cylinder (407) at the sampling point to prevent it from hitting the wall when it is inserted. Step 5: Activate the rotating propulsion mechanism (406) inside the sampling device (4) to push the sampling rod (404) down, and the sample tube (408) inside the sampling rod (404) will also perform the downward insertion action; Step 6: During the insertion process, monitor the alignment of the sampling rod (404) with the isolation tube (407) inside the chamber and make timely adjustments to ensure that the sampling rod (404) can be smoothly and without collision inserted into the isolation tube (407). Rely on the constraint of the isolation tube (407) to control the shaking of the sampling rod (404) during the insertion process, and ensure the integrity of the sample after entering the sample tube (408). Step 7: When the predetermined insertion depth is reached, stop the insertion action, reverse the rotation propulsion mechanism (406), and lift the upper extraction rod (404) and sample cylinder (408) together to leave the isolation cylinder (407). Step 8: After lifting is complete, start the unfolding mechanism (5) in the opposite direction to flip the sampling device (4) from the upright position to the horizontal position; Step 9: Push the track to its full length, push the sampling rod (404) of the sampling device (4) into the delivery channel, and prepare to send out the sample; Step 10: Check that the three high-pressure sealing ball valves inside the pressure-maintaining and authentic delivery device (6) are closed, and inject water into the pressure-maintaining and authentic delivery device (6) to pressurize it until it is balanced with the pressure inside the combustible ice storage test chamber (1); Step 11: Open the two high-pressure sealing ball valves inside the pressure-maintaining and fidelity-preserving delivery device (6) to connect the pressure-maintaining and fidelity-preserving delivery device (6) with the combustible ice storage test chamber (1); Step 12: Activate the ejection device (402) on the upper part of the sampling device (4), push the sample tube (408) from the sampling rod (404) into the pressure-holding and fidelity delivery device (6), and remove the sampling device (4). Step 13: Close all valves of the pressure holding and fidelity delivery device (6), disconnect the external flange (13), and connect the pressure holding and fidelity delivery device (6) to the matching slice scanning mechanism to achieve scanning imaging; Step 14: Done.

2. The method for pressure-maintaining and high-fidelity sampling in the combustible ice accumulation test chamber as described in claim 1, characterized in that: The dry-wet conversion chamber (2) and the pressure-preserving and high-fidelity delivery device (6) are at the same height.

3. The method for pressure-maintaining and high-fidelity sampling in the combustible ice accumulation test chamber as described in claim 1, characterized in that: The central axes of the dry-wet conversion chamber (2) and the pressure-preserving and fidelity delivery device (6) are both perpendicular to the central axis of the combustible ice accumulation test chamber (1).

4. The method for pressure-maintaining and high-fidelity sampling in the combustible ice accumulation test chamber as described in claim 1, characterized in that: The dry-wet conversion chamber (2) and the combustible ice accumulation test chamber (1) are integrated into one structure.

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