Experimental system for observing hydrate dissociation water transport rule

Abstract

The invention provides an experimental system for observing a hydrate dissociation water transfer rule, during an experiment, a transparent pressure container is rotated to a first position, a hydrate area is located below, and at the moment, the hydrate area is filled with sand and distilled water dissolved with a tracer agent. The low-temperature container is opened, the second pipeline is closed, the first pipeline is opened, and methane is injected into the transparent pressure container to reach the preset pressure. And after the hydrate is stably generated, opening the second pipeline, displacing movable pore water of the unsynthesized hydrate in the hydrate area by using methane gas, and closing the second pipeline and the first pipeline when the second pipeline does not discharge water any more. Turning over the transparent pressure container to a second position, filling the gas cavity area with sand, and introducing methane gas into the transparent pressure container until the pressure reaches the specified pressure after sand filling is completed. And then adjusting the back pressure of the first pipeline, slowly reducing the pressure of the gas cavity area, and recording a hydrate dissociation water transportation path by using an image recording device.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrate-shallow gas joint development, and in particular to an experimental system for observing the migration law of hydrate dissociation water. Background Art

[0002] The South China Sea's deepwater shallow gas fields, exceeding 100 billion cubic meters, differ from conventional deep gas reservoirs in that they are relatively shallow, typically located hundreds to thousands of meters below the seafloor. The formation's temperature and pressure conditions lie within the critical range for the stable existence of natural gas hydrates, resulting in a geological structure where shallow gas reservoirs coexist with an overlying hydrate caprock. Because the two pore pressure systems are interconnected, during shallow gas development, reservoir depressurization is simultaneously transmitted to the hydrate layer, causing hydrate phase equilibrium instability and decomposition, triggering downward migration of decomposed gas and water. This poses risks such as disrupted gas-liquid two-phase flow in the wellbore and increased sand production from the reservoir, seriously threatening development efficiency and safety.

[0003] Current development and monitoring technologies for such complex systems have significant limitations: on the one hand, existing experimental devices mostly use physical separation models to simulate hydrate and shallow gas systems, which cannot reflect the direct contact characteristics of the sediments in which the two phases are located; on the other hand, traditional monitoring methods (such as resistivity and acoustic detection) are mostly used to monitor the overall changes in fluid saturation in the sediment system, which makes it difficult to describe the migration path and rate of dissociated water produced by hydrate decomposition in porous media.

[0004] Therefore, there is an urgent need to develop an experimental device that can realistically simulate a pressure-connected shallow gas-hydrate superposition system and monitor the migration patterns of dissociated water, so as to provide key data support for optimizing mining processes and assessing safety risks. Summary of the Invention

[0005] The present invention aims to address at least one of the technical problems existing in the prior art. To this end, the present invention provides an experimental system for observing the migration patterns of dissociated water in hydrates. This system aims to address the lack of an experimental device that can realistically simulate a pressure-connected shallow gas-hydrate stack system and detect the migration patterns of dissociated water.

[0006] The present invention provides an experimental system for observing the migration law of hydrate dissociation water, comprising a cryogenic container, a rotating support, a transparent pressure container, a first pipeline, a second pipeline, and an image recording device. The rotating support, the transparent pressure container, and the image recording device are all arranged in the cryogenic container. The transparent pressure container is provided with an air cavity area and a hydrate area. The first pipeline is connected to the air cavity area, and the second pipeline is connected to the hydrate area. The transparent pressure container is connected to the rotating portion of the rotating support. The rotating support is used to rotate the transparent pressure container about a horizontal axis and to fix the transparent pressure container in a first position or a second position. When the transparent pressure container is in the first position, the air cavity area is located above the hydrate area. When the transparent pressure container is in the second position, the hydrate area is located above the air cavity area. One end of the transparent pressure container located in the air cavity area is open, and a closable cover is provided at the open end. The image recording device is arranged on one side of the transparent pressure container, and its imaging range at least covers the transparent pressure container.

[0007] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, a first sand screen is provided in the air cavity area of the transparent pressure vessel away from the hydrate area, and the edge of the first sand screen is detachably connected to the inner wall of the transparent pressure vessel; A second sand isolation net is provided at a position of the hydrate region of the transparent pressure vessel away from the air cavity region, and an edge of the second sand isolation net is connected to the inner side wall of the transparent pressure vessel.

[0008] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, the low-temperature container at least includes a cold storage or a low-temperature test box.

[0009] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, the rotating support includes: Support frame; A clamper, the clamper is used to clamp or release the transparent pressure container, the clamper is rotatably connected to the support frame, and the rotation axis is along the horizontal direction; A limiting device is provided between the clamp and the support frame, and is used to limit the clamp to the first position or the second position.

[0010] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, the clamp and the support frame are connected by a rotating shaft, and the limiting device includes a locking nut, which is threadedly connected to the end of the rotating shaft away from the clamp. When the clamp is rotated to the first position or the second position, the locking nut is used to tighten against the support frame.

[0011] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, the limiting device includes a damper, and the damper is arranged between the clamper and the support frame.

[0012] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, the holder includes a clamp.

[0013] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, the cover includes: a sealing portion, the sealing portion being a disc-shaped structure, the outer diameter of the sealing portion being at least equal to the outer diameter of the transparent pressure vessel, and the side of the sealing portion close to the transparent pressure vessel being in sealing contact with the end face of the transparent pressure vessel; The connecting part is a circular ring structure, and the connecting part is arranged on the side where the sealing part contacts the transparent pressure container. The outer side surface of the connecting part is in sealing contact with the inner wall of the transparent pressure container, and the first sand isolation net is connected to the end of the connecting part away from the sealing part.

[0014] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, a first stop valve is provided on the first pipeline, and a second stop valve is provided on the second pipeline.

[0015] According to the experimental system for observing the migration law of hydrate dissociation water provided by the present invention, the image recording device includes a high-speed camera.

[0016] The present invention has the following advantages due to the adoption of the above technical solution: The present invention provides an experimental system for observing the migration of hydrate dissociation water. During the experiment, the transparent pressure vessel can be rotated to the first position, so that the hydrate area is located at the bottom. At this time, the lid is opened and sand is added to the transparent pressure vessel so that the sand fills the hydrate area. Then, distilled water containing a tracer is added to the pores of the sand, and the lid is reconnected to the transparent pressure vessel. The low-temperature container is opened to provide low-temperature conditions for hydrate synthesis. The second pipeline is closed, and the first pipeline is opened to inject methane gas into the transparent pressure vessel. This not only provides methane gas for hydrate synthesis, but also provides a high-pressure environment for hydrate synthesis. After hydrate formation stabilizes, the second pipeline is opened and methane gas is continued to be introduced into the transparent pressure vessel through the first pipeline to displace the mobile pore water in the hydrate area that has not yet formed hydrate. When the second pipeline stops discharging water, the second pipeline and the first pipeline are closed. The lid is then opened and sand is added to the air cavity area so that the sand fills the air cavity area. The lid is then reconnected to the transparent pressure vessel. Then open the first pipeline, introduce methane gas into the transparent pressure vessel until the specified pressure is reached, and then close the first pipeline. The transparent pressure vessel is turned upside down by rotating the bracket to the second position. At this time, the hydrate area is located above the air cavity area, forming a superimposed state of hydrates overlying shallow gas. Keep the second pipeline closed, control the back pressure of the first pipeline, slowly reduce the pressure in the air cavity area, the hydrate decomposes, and the migration path of the hydrate dissociation water is recorded using an image recording device. The experimental system for observing the migration law of hydrate dissociation water provided by the present invention can simulate a hydrate-shallow gas system in direct contact and pressure connection, and on this basis monitor the migration law of dissociated water caused by the hydrate decomposition process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0018] Figure 1 1 is a schematic structural diagram of an experimental system for observing the migration law of hydrate dissociation water, provided by an embodiment of the present invention, in which a transparent pressure vessel is located in a first position and before sand is filled into the air cavity area; Figure 2 This is a schematic structural diagram of an experimental system for observing the migration law of hydrate dissociation water when the transparent pressure vessel provided by one embodiment of the present invention is located in the second position.

[0019] Reference numerals: 100: Low-temperature container; 200: Transparent pressure container; 210: First sand screen; 220: Second sand screen; 230: Air cavity area; 240: Hydrate area; 250: Cover; 300: First pipeline; 310: First stop valve; 400: Second pipeline; 410: Second stop valve; 500: High-speed camera; 611: Base; 612: Support arm; 620: Clamp; 630: Locking nut. DETAILED DESCRIPTION

[0020] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0021] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature identified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means more than two, unless otherwise specifically defined.

[0023] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0024] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0025] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0026] The present invention provides an experimental system for observing the migration law of hydrate dissociation water, comprising a low-temperature container, a rotating bracket, a transparent pressure container, a first pipeline, a second pipeline and an image recording device. The rotating bracket, the transparent pressure container and the image recording device are all arranged in the low-temperature container. An air cavity area and a hydrate area are provided in the transparent pressure container. The first pipeline is connected to the air cavity area, the second pipeline is connected to the hydrate area, the transparent pressure container is connected to the rotating part of the rotating bracket, the rotating bracket is used to rotate the transparent pressure container around a horizontal axis, and the rotating bracket is used to fix the transparent pressure container in a first position and a second position. When the transparent pressure container is in the first position, the air cavity area is located above the hydrate area. When the transparent pressure container is in the second position, the hydrate area is located above the air cavity area. The image recording device is arranged on one side of the transparent pressure container, and the shooting range at least covers the transparent pressure container. The present invention provides an experimental system for observing the migration of hydrate dissociation water. During the experiment, the transparent pressure vessel can be rotated to the first position, so that the hydrate area is located at the bottom. At this time, the lid is opened and sand is added to the transparent pressure vessel so that the sand fills the hydrate area. Then, distilled water containing a tracer is added to the pores of the sand, and the lid is reconnected to the transparent pressure vessel. The low-temperature container is opened to provide low-temperature conditions for hydrate synthesis. The second pipeline is closed, and the first pipeline is opened to inject methane gas into the transparent pressure vessel. This not only provides methane gas for hydrate synthesis, but also provides a high-pressure environment for hydrate synthesis. After hydrate formation stabilizes, the second pipeline is opened and methane gas is continued to be introduced into the transparent pressure vessel through the first pipeline to displace the mobile pore water in the hydrate area that has not yet formed hydrate. When the second pipeline stops discharging water, the second pipeline and the first pipeline are closed. After depressurization, the lid is opened, sand is added to the air cavity area so that the sand fills the air cavity area, and the lid is reconnected to the transparent pressure vessel. Then open the first pipeline, introduce methane gas into the transparent pressure vessel until the specified pressure is reached, and then close the first pipeline. The transparent pressure vessel is turned upside down by rotating the bracket to the second position. At this time, the hydrate area is located above the air cavity area, forming a superimposed state of hydrates overlying shallow gas. Keep the second pipeline closed, control the back pressure of the first pipeline, slowly reduce the pressure in the air cavity area, the hydrate decomposes, and the migration path of the hydrate dissociation water is recorded using an image recording device. The experimental system for observing the migration law of hydrate dissociation water provided by the present invention can simulate a hydrate-shallow gas system in direct contact and pressure connection, and on this basis monitor the migration law of dissociated water caused by the hydrate decomposition process.

[0027] The following combination Figure 1 and Figure 2 The present invention describes an experimental system for observing the migration law of hydrate dissociation water.

[0028] An embodiment of the present invention provides an experimental system for observing the migration law of hydrate dissociation water, including a cryogenic container 100, a rotating support, a transparent pressure container 200, a first pipeline 300, a second pipeline 400 and an image recording device.

[0029] The low-temperature container 100 can at least be a low-temperature test box or a cold storage, etc., for providing a low-temperature environment, and the ambient temperature is adjustable.

[0030] The transparent pressure vessel 200 can be a cylindrical barrel structure, the interior of which is divided into a hydrate area 240 and an air cavity area 230 along the axial direction. One end of the transparent pressure vessel 200 located in the air cavity area 230 is open, and a cover body 250 is detachably connected to the end.

[0031] The cover 250 includes a sealing portion and a connecting portion. The sealing portion is a disc-shaped structure with an outer diameter that can be equal to or larger than the outer diameter of the transparent pressure vessel 200, so that it can completely cover the opening of the transparent pressure vessel 200. The side of the sealing portion closest to the transparent pressure vessel 200 is in sealing contact with the end face of the transparent pressure vessel 200. The connecting portion is an annular structure, disposed on the side of the sealing portion that contacts the transparent pressure vessel 200. The connecting portion is configured to be inserted into the transparent pressure vessel 200, and the outer side of the connecting portion is in sealing contact with the inner wall of the transparent pressure vessel 200.

[0032] When the cover 250 is opened, sand and distilled water containing a tracer can be filled into the hydrate region 240, and sand can also be filled into the air cavity region 230. During the experiment, the cover 250 needs to be kept closed.

[0033] The rotating bracket includes a support frame, a clamp 620, and a limiting device. The clamp 620 is used to clamp or release the transparent pressure container 200. The clamp 620 is rotatably connected to the support frame, with the axis of rotation being horizontal. The limiting device is disposed between the clamp 620 and the support frame and is used to restrict the clamp 620 to a first position or a second position.

[0034] Specifically, the support frame may include a base 611 and support arms 612. The support arms 612 include two support arms 612, both extending vertically and distributed in the left-right direction. An axial hole is provided at the top of the support arm 612, penetrating the support arm 612 in the left-right direction, and the axes of the axial holes of the two support arms 612 are collinear.

[0035] The clamp 620 can be a clamp comprising two separate half rings, the ends of which are connected by bolts and nuts. A rotating shaft extending radially outward from the half ring is provided on the outer side of the arc top of the half ring, and the rotating shaft is rotatably connected to the shaft hole.

[0036] When installing the transparent pressure vessel 200, loosen the bolts and nuts, then place the transparent pressure vessel 200 between the two half rings, and finally tighten the bolts and nuts so that the two half rings are tightly embraced on the outside of the transparent pressure vessel 200, thereby achieving the effect of rotating the transparent pressure vessel 200 along the horizontal axis.

[0037] The limiting device is provided between the clamp 620 and the support frame, and is used to limit the clamp 620 to the first position or the second position.

[0038] Specifically, the rotation shaft can be provided on a side of the support arm 612 away from the clamp 620. A locking nut 630 can be threaded onto this side of the rotation shaft. The locking nut 630 serves as a limiting device. When the transparent pressure container 200 needs to be fixed in the first or second position, the locking nut 630 is tightened. The locking nut 630 then abuts against the support arm 612, limiting the relative rotation of the clamp 620 and the support arm 612. When the transparent pressure container 200 needs to be rotated, the locking nut 630 is loosened, and the clamp 620 can rotate freely relative to the support arm 612.

[0039] Alternatively, the limiting device can also be a damper, which is arranged between the rotating axis of the clamp 620 and the axial hole of the support arm 612. In this way, the clamp 620 can rotate relative to the support arm 612 under the action of external force, and can stop at any angle after the external force disappears.

[0040] One end of the first pipe 300 is connected to the end of the air cavity region 230 of the transparent pressure vessel 200, and the other end can be connected to a methane gas source. One end of the second pipe 400 is connected to the end of the hydrate region 240 of the transparent pressure vessel 200, and the other end is vented.

[0041] Specifically, a first stop valve 310 is provided on the first pipeline 300, and a second stop valve 410 is provided on the second pipeline 400. The first stop valve 310 and the second stop valve 410 are both used to control the opening and closing or exhaust back pressure of the corresponding pipeline.

[0042] In some embodiments, a first sand screen 210 is disposed in the air cavity region 230 of the transparent pressure vessel 200, away from the hydrate region 240. The edge of the first sand screen 210 is detachably connected to the inner sidewall of the transparent pressure vessel 200, or there is no connection between the two. In this case, the first sand screen 210 is connected to the end of the connection portion of the cover away from the sealing portion. In this manner, when filling the air cavity region 230 with sand, the first sand screen 210 can be removed from the transparent pressure vessel 200. Alternatively, when the cover 250 is opened, the first sand screen 210 moves with the cover 250 to the exterior of the transparent pressure vessel 200.

[0043] A second sand screen 220 is provided in the hydrate region 240 of the transparent pressure vessel 200, away from the air cavity region 230. The edge of the second sand screen 220 is connected to the inner wall of the transparent pressure vessel 200. Since the hydrate region 240 needs to be filled with sand, the second sand screen 220 can prevent sand from falling.

[0044] In some embodiments, the image recording device includes a high-speed camera 500. A lifting bracket may be provided at the bottom of the high-speed camera 500 to change the height of the high-speed camera 500.

[0045] The experimental process of the experimental system for observing the migration law of hydrate dissociation water provided by the present invention is as follows: The transparent pressure container 200 is rotated to the first position and fixed, where the air cavity area 230 is located above the hydrate area 240 , and then the low-temperature container 100 is opened to provide a low-temperature environment for hydrate synthesis.

[0046] Open the cover 250 and fill sand into the transparent pressure vessel 200. Since the hydrate area 240 is at the bottom, the sand particles enter the hydrate area 240 under the action of gravity until the lower hydrate area 240 is filled. Then, distilled water with a tracer dissolved in it is filled into the hydrate area 240. The distilled water fills the pores of the sand particles, and then the cover 250 is closed.

[0047] Close the second stop valve 410, open the first stop valve 310, and use the first pipeline 300 to inject methane gas into the transparent pressure vessel 200 to a specified pressure, thereby providing methane gas for hydrate synthesis on the one hand and high-pressure conditions for hydrate synthesis on the other.

[0048] After hydrate formation stabilizes, the second stop valve 410 is opened to maintain the pressure difference between the first pipeline 300 and the second pipeline 400 to displace the mobile pore water in the hydrate area 240 that has not synthesized hydrate until water no longer flows out of the second pipeline 400, and then the first stop valve 310 and the second stop valve 410 are closed.

[0049] Open the lid 250 of the transparent pressure vessel 200, separate the first sand screen 210 along with the lid 250, quickly fill the air cavity 230 with sand, and then close the lid 250. While keeping the second shut-off valve 410 closed, open the first shut-off valve 310 and inject methane gas into the transparent pressure vessel 200 to the specified pressure.

[0050] The transparent pressure container 200 is turned over to the second position. At this time, the hydrate region 240 is located above the air cavity region 230. The sand grains in the air cavity region 230 are supported on the bottom of the hydrates and sand grains in the hydrate region 240, forming a shallow gas-overlying hydrate superimposed geological structure.

[0051] The second stop valve 410 is kept closed, the back pressure of the first stop valve 310 is controlled, and the pressure of the air cavity area 230 is slowly reduced. At the same time, the migration path of the hydrate dissociation water is recorded using a high-speed camera 500.

[0052] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. An experimental system for observing the migration law of hydrate dissociation water, characterized in that: The invention comprises a low-temperature container (100), a rotating bracket, a transparent pressure container (200), a first pipeline (300), a second pipeline (400) and an image recording device, wherein the rotating bracket, the transparent pressure container (200) and the image recording device are all arranged in the low-temperature container (100), an air cavity area (230) and a hydrate area (240) are arranged in the transparent pressure container (200), the first pipeline (300) is connected to the air cavity area (230), the second pipeline (400) is connected to the hydrate area (240), the transparent pressure container (200) is connected to the rotating part of the rotating bracket, and the rotating bracket is used to make the transparent pressure container (200) rotate around a horizontal axis. The transparent pressure vessel (200) is rotated, and the rotating bracket is used to fix the transparent pressure vessel (200) at a first position or a second position. When the transparent pressure vessel (200) is located at the first position, the air cavity area (230) is located above the hydrate area (240). When the transparent pressure vessel (200) is located at the second position, the hydrate area (240) is located above the air cavity area (230). One end of the transparent pressure vessel (200) located at the air cavity area (230) is open, and a closable cover (250) is provided at the open end. The image recording device is provided on one side of the transparent pressure vessel (200), and the shooting range at least covers the transparent pressure vessel (200).

2. The experimental system for observing the migration law of hydrate dissociation water according to claim 1, characterized in that: A first sand isolation net (210) is provided at a position of the air cavity region (230) of the transparent pressure container (200) away from the hydrate region (240), and an edge of the first sand isolation net (210) is detachably connected to the inner side wall of the transparent pressure container (200); A second sand isolation net (220) is provided at a position of the hydrate region (240) of the transparent pressure container (200) away from the air cavity region (230), and an edge of the second sand isolation net (220) is connected to the inner side wall of the transparent pressure container (200).

3. The experimental system for observing the migration law of hydrate dissociation water according to claim 1, characterized in that: The low-temperature container (100) at least includes a cold storage or a low-temperature test box.

4. The experimental system for observing the migration law of hydrate dissociation water according to claim 1, characterized in that: The rotating bracket includes: Support frame; A clamper (620), the clamper (620) is used to clamp or release the transparent pressure container (200), the clamper (620) is rotatably connected to the support frame, and the rotation axis is along the horizontal direction; A limiting device is provided between the clamp (620) and the support frame, and is used to limit the clamp (620) to the first position or the second position.

5. The experimental system for observing the migration law of hydrate dissociation water according to claim 4, characterized in that: The clamp (620) is connected to the support frame via a rotating shaft, and the limiting device includes a locking nut (630). The locking nut (630) is threadedly connected to an end of the rotating shaft away from the clamp (620). When the clamp (620) is rotated to the first position or the second position, the locking nut (630) is used to press against the support frame.

6. The experimental system for observing the migration law of hydrate dissociation water according to claim 4, characterized in that: The limiting device comprises a damper, and the damper is arranged between the clamp (620) and the support frame.

7. The experimental system for observing the migration law of hydrate dissociation water according to claim 5, characterized in that: The holder (620) comprises a clamp.

8. The experimental system for observing the migration law of hydrate dissociation water according to claim 2, characterized in that: The cover (250) comprises: a sealing portion, the sealing portion being a disc-shaped structure, the outer diameter of the sealing portion being at least equal to the outer diameter of the transparent pressure vessel (200), and the side of the sealing portion close to the transparent pressure vessel (250) being in sealing contact with the end face of the transparent pressure vessel (250); The connecting portion is a circular ring structure, and the connecting portion is arranged on the side where the blocking portion contacts the transparent pressure container (250), the outer side surface of the connecting portion is in sealing contact with the inner side wall of the transparent pressure container (250), and the first sand isolation net (210) is connected to an end of the connecting portion away from the blocking portion.

9. The experimental system for observing the migration law of hydrate dissociation water according to claim 1, characterized in that: The first pipeline (300) is provided with a first stop valve (310), and the second pipeline (400) is provided with a second stop valve (410).

10. The experimental system for observing the migration law of hydrate dissociation water according to claim 1, characterized in that: The image recording device comprises a high-speed camera (500).

Images