Marine hydrate cementation particle collision gel breaking separation device

Abstract

The invention discloses a marine hydrate cementation particle collision gel breaking separation device which comprises a lower outer layer pipe and an inner layer pipe assembly located in the lower outer layer pipe, and the inner layer pipe assembly comprises a lower inner layer pipe; a rubber breaking sleeve is arranged in the lower inner layer pipe, the bottom of the rubber breaking sleeve is closed, a plurality of jet flow holes which are opposite in pairs in the radial direction are formed in the side wall of the rubber breaking sleeve, and an annular space is formed between the rubber breaking sleeve and the lower inner layer pipe; the pushing shaft is arranged in the rubber breaking sleeve in a sliding fit mode, and the driving mechanism is used for driving the pushing shaft to do axial reciprocating motion. The invention provides a marine hydrate cementation particle collision gel breaking and separating device to solve the problems that in the prior art, the gel breaking force is small, and the gel breaking and separating effect on cementation particles is insufficient, and the purposes that the gel breaking efficiency of the cementation particles is improved, and then the recovery efficiency of hydrates is improved are achieved.

Description

Technical Field

[0001] The invention relates to the field of hydrate exploitation, and in particular to a marine hydrate cementing particle collision debonding and separation device. Background Art

[0002] Natural gas hydrate, also known as combustible ice, is an ice-like solid compound formed by hydrocarbon gases, mainly methane, and water under certain temperature and pressure conditions. The global reserves of natural gas hydrate are huge, and it is a clean, high-quality energy source, which plays an important role in future energy strategies.

[0003] Based on the reservoir characteristics of non-diagenetic natural gas hydrates in the South my country Sea, such as weak cementation, poor stability, and no dense caprock, the existing technology proposed a new method of solid fluidized mining, and successfully carried out a trial production of natural gas hydrates in 2017. The core idea of ​​the solid fluidized mining method is to use water jets to break up the hydrate reservoir and fluidize it into slurry without changing the temperature and pressure conditions, and then recover the hydrate to the platform through recovery, separation and lifting.

[0004] Due to the cementing properties of hydrate sediments, the hydrate slurry formed after fluidized crushing contains a large number of cementing particles. The cementing effect between hydrate and sand particles will cause a large number of hydrate particles to be carried in the sand backfilled to the bottom of the well, and cause a large number of sand particles to be entrained in the recovered hydrate slurry, which greatly reduces the recovery efficiency of hydrates. Therefore, how to achieve the debonding and separation of hydrates and sand is a key link in the fluidized mining process.

[0005] In the prior art: Chinese patent with publication number CN109882147A discloses an integrated downhole hydrate in-situ separation parallel device with a large processing capacity, which mainly solves the problems of severe sand production and low separation efficiency of existing separators during hydrate mining. However, this device takes dispersed hydrate and sand particles as separation objects, and does not consider the bonding between the two. Chinese patent with publication number CN113090244A discloses a natural gas hydrate cyclone self-rotation debonding method and separation device, and the separation device composed of a preliminary debonder, a cyclone debonding cylinder and a cyclone separation cylinder realizes debonding and separation of natural gas hydrate sediment slurry, but this device will cause the wellbore diameter to increase, resulting in an increase in the diameter of the drilling wellbore, reducing the reservoir stability and increasing the risk of wellbore reservoir collapse. Chinese patent with publication number CN214091833U discloses a debonding separation mechanism and a natural gas hydrate-sand cemented particle debonding separation device, but the debonding force generated by this centrifugal method is also relatively small, and the debonding efficiency of the cemented particles is still low.

[0006] In summary, the debonding force generated by the existing hydrate recovery technologies is relatively small, and the debonding and separation effect on the cementing particles in the hydrate slurry is insufficient, resulting in low hydrate recovery efficiency. Summary of the invention

[0007] The present invention provides a marine hydrate cementing particle collision degumming and separation device to solve the problems of small degumming force and insufficient degumming and separation effect on cementing particles in the prior art, thereby achieving the purpose of improving the degumming efficiency of cementing particles and further improving the hydrate recovery efficiency.

[0008] The present invention is achieved through the following technical solutions:

[0009] A device for separating marine hydrate cemented particles by collision and breaking the gel, comprises a lower outer tube, an inner tube assembly located inside the lower outer tube, the inner tube assembly comprising a lower inner tube; a breaking sleeve is arranged inside the lower inner tube, the bottom of the breaking sleeve is closed, a plurality of radially opposite jet holes are provided on the side wall of the breaking sleeve, and an annulus is provided between the breaking sleeve and the lower inner tube; and a driving mechanism is also included which is slidably fitted with a driving shaft inside the breaking sleeve and is used to drive the driving shaft to make axial reciprocating motion.

[0010] In view of the problem that the debonding force in the prior art is relatively small and the debonding and separation effect on the cemented particles is insufficient, the present invention proposes a marine hydrate cemented particle collision debonding and separation device. Based on the double-layer tube technology in hydrate mining, the present application has structures such as a lower outer tube and an inner tube assembly. The inner tube assembly in the present application includes a debonding sleeve, and the bottom of the debonding sleeve is closed and a jet hole is provided on the side wall. The driving shaft performs axial reciprocating motion inside the debonding sleeve under the drive of the driving mechanism. The specific driving method of the driving mechanism for the driving shaft is not specifically limited here. Any linear driving method that can be realized by technical personnel in this field according to the prior art can be applied to the present application.

[0011] When the present application is in operation, it is connected above the downhole power drill. High-pressure fluid flows downward from the annulus between the lower outer tube and the inner tube assembly into the downhole power drill, driving the downhole power drill to rotate and simultaneously performing jet crushing. The obtained hydrate slurry returns to the existing inner tube and enters the lower inner tube in the present application. During this process, the driving mechanism drives the driving shaft to make axial reciprocating motion. Each upward movement of the driving shaft will generate a suction force in the debonding sleeve. Under the action of the suction force, the hydrate slurry recovered to the lower inner tube is periodically sucked into the debonding sleeve through the jet holes. Since the jet holes are opposite to each other in radial direction, the hydrate slurry jetted in will undergo strong convection collision in the debonding sleeve. Under the action of the strong collision force, the debonding and dispersion of the hydrate cementing particles are achieved. The present application causes the recovered hydrate slurry to continuously undergo jet collision under the action of suction, thereby achieving a degumming effect of collision crushing, significantly optimizing the degumming effect on cemented hydrate particles and sand particles, and improving the degumming efficiency of cemented particles, which is beneficial to improving the recovery rate of natural gas hydrates.

[0012] Furthermore, the outer diameter of the driving shaft is equal to the inner diameter of the rubber-breaking sleeve, and thus part of the jet hole can be blocked by the driving shaft;

[0013] When the driving shaft is at the top of the stroke, all the jet holes are connected to the inside of the rubber-breaking sleeve, that is, all the jet holes are open;

[0014] When the push shaft is at the bottom of the stroke, some of the jet holes are not connected to the inside of the debonding sleeve, that is, some of the jet holes are open and the rest of the jet holes are closed. This arrangement ensures that some of the jet holes are always open, ensuring that the internal flow channel is unobstructed during hydrate extraction and avoiding temporary well closure or tool self-locking.

[0015] Furthermore, the inner layer tube assembly further comprises an intermediate joint connected above the lower inner layer tube, and a middle inner layer tube connected above the intermediate joint;

[0016] The driving mechanism includes a piston head axially slidingly fitted in the middle inner tube, a first elastic member connected between the piston head and the intermediate joint, and an excitation component for generating pressure fluctuations inside the middle inner tube and in the space at the top of the piston head; the piston head is connected to the driving shaft.

[0017] When the driving mechanism needs to work, the excitation component generates pressure fluctuations in the area inside the middle inner layer tube and on the top of the piston head: when the pressure increases, the high pressure drives the piston head to move downward, driving the push shaft to move downward synchronously, and the first elastic member is compressed during this process; when the pressure decreases, the first elastic member releases the elastic force, and under the action of its elastic restoring force, it pushes the piston head to move upward, driving the push shaft to move upward synchronously.

[0018] The excitation component in this solution can be implemented by any existing technology that can provide pressure fluctuations or pressure pulses, and is not specifically limited here. In addition, those skilled in the art should understand that in order to ensure smooth flow, the piston head in this solution is a hollow structure.

[0019] Furthermore, the inner layer tube assembly further comprises an upper inner layer tube connected above the middle inner layer tube;

[0020] The excitation component includes an inner sleeve arranged inside the upper inner tube, a throttling sleeve axially slidingly fitted in the inner sleeve, and a second elastic member connected between the throttling sleeve and the inner sleeve, wherein the throttling sleeve is used to generate a throttling pressure drop from bottom to top.

[0021] When the present application is working, there is always fluid flowing back inside the inner tube assembly. Therefore, the present scheme utilizes the energy of the flowing back fluid to set a certain section of the inner tube assembly as a throttling sleeve, so that a pressure drop is generated when the hydrate slurry passes through the throttling sleeve from bottom to top. Under the throttling effect, the pressure at the upstream end (bottom space) of the throttling sleeve increases, and the pressure at the downstream end (top space) of the throttling sleeve decreases. The high-pressure area at the bottom of the throttling sleeve can drive the piston head to move downward and the throttling sleeve to move upward at the same time until the pressure in the high-pressure area is released. At this time, the piston head is reset upward under the action of the first elastic member, and the throttling sleeve is reset downward under the action of the second elastic member. The above process is repeated continuously during the working process of the present application, thereby achieving the effect of providing the required pressure fluctuation.

[0022] It can be seen that this scheme utilizes the energy of the hydrate slurry that returns during the hydrate extraction process. The required pressure fluctuation can be obtained through ingenious structural design without the need for additional pressure source or power source, which significantly improves the operability of collision debonding and avoids problems such as bulky and bloated equipment that is inconvenient to enter the well.

[0023] In addition, the throttling sleeve in the present solution can be implemented by any existing structure that has a throttling pressure drop function and can generate a pressure difference at both ends. The throttling pressure drop structure / equipment / tools / valves, etc. in the fluid transportation process in the prior art can be applied to the present application, such as installing a throttling valve therein.

[0024] Preferably, the interior of the throttling sleeve includes a main cavity, a variable diameter cavity, a throttling hole and a variable diameter hole which are connected in sequence from bottom to top; the inner diameter of the throttling hole is smaller than the inner diameter of the main cavity; the inner diameter of the variable diameter cavity gradually decreases from bottom to top; the inner diameter of the variable diameter hole gradually increases from top to bottom.

[0025] This solution clearly defines the specific structure of the throttling sleeve to ensure that the required pressure difference is stably generated at both ends thereof.

[0026] Furthermore, a pressure relief annulus is provided between the inner sleeve and the upper inner pipe; a plurality of pressure relief holes are provided on the side wall of the inner sleeve, and the pressure relief holes are connected to the pressure relief annulus;

[0027] When the throttling sleeve is at the top of the stroke, the pressure relief hole is connected to the inside of the inner sleeve; at this time, the pressure in the high-pressure area below the throttling sleeve enters the pressure relief annulus through the pressure relief hole to release the pressure, so that the piston head and the throttling sleeve begin to reset;

[0028] When the throttling sleeve is at the bottom of the stroke, the pressure relief hole is not connected to the interior of the inner sleeve; at this time, the pressure in the high-pressure area below the throttling sleeve increases rapidly, ensuring that the piston head starts to move downward and the throttling sleeve starts to move upward.

[0029] Furthermore, the inner layer pipe assembly also includes a hanging joint connected above the upper inner layer pipe; the pressure relief annulus is communicated with the interior of the hanging joint.

[0030] The inside of the suspension joint and the inside of the upper inner layer pipe are normal fluid return channels. At the same time, this solution ensures that the pressure relief annulus is always connected to the inside of the suspension joint to provide a more efficient and stable pressure relief space, avoiding pressure buildup in the pressure relief annulus that may cause tool jamming or self-locking.

[0031] Furthermore, it also includes a double-layer pipe joint connected to the top of the lower outer layer pipe and the inner layer pipe assembly, an upper outer layer pipe and a separator sleeve connected above the double-layer pipe joint, and the separator sleeve is located inside the upper outer layer pipe; a downward flow channel and an upward flow channel are arranged in the double-layer pipe joint;

[0032] The top end of the descending flow channel is communicated with the annulus between the upper outer layer pipe and the separator sleeve, and the bottom end of the descending flow channel is communicated with the annulus between the lower outer layer pipe and the inner layer pipe assembly;

[0033] The top end of the upward flow channel is communicated with the interior of the separator sleeve, and the bottom end of the upward flow channel is communicated with the interior of the inner layer pipe assembly.

[0034] This solution clearly defines the structure of the top of the lower outer tube and the inner tube assembly, which is convenient for adapting to the existing double-layer drill pipe in the hydrate production string, ensuring smooth flow of high-pressure fluid and hydrate slurry and ensuring the versatility of this application.

[0035] Furthermore, it also includes an upper joint connected to the top of the separator sleeve and a cyclone arranged inside the separator sleeve; a tangential inlet is arranged on the side of the cyclone, an overflow port is arranged on the top, and an underflow port is arranged on the bottom, the tangential inlet is communicated with the interior of the separator sleeve, the overflow port runs through the upper joint, the underflow port is connected to the sand discharge channel, and the sand discharge channel is located in the double-layer pipe joint and extends to the side wall of the double-layer pipe joint.

[0036] After the hydrate slurry is degelled by the jet collision of the jet hole, it returns to the inside of the separator sleeve step by step, enters the cyclone through the tangential inlet, and the separated mud and sand particles enter the sand discharge channel through the bottom flow port and are discharged, and the separated hydrate continues to return upward through the overflow port.

[0037] Furthermore, the outer diameter of the cyclone gradually decreases from top to bottom.

[0038] The cross-sectional area of ​​the annulus between the cyclone and the separator sleeve is gradually reduced from bottom to top, so that the fluid is accelerated to flow upward after entering the separator sleeve, and enters the tangential inlet at a faster flow rate, and has a larger initial velocity in the cyclone, which is conducive to the hydrate slurry to obtain a larger centrifugal force in the cyclone, improves the separation ability of hydrate particles and mud and sand particles, and can use centrifugal force to break the gel again, thereby further improving the gel breaking ability of the present application.

[0039] Compared with the prior art, the present invention has at least the following advantages and beneficial effects:

[0040] 1. The present invention provides a marine hydrate cementing particle collision degumming and separation device, which enables the recovered hydrate slurry to continuously undergo jet collision under the action of suction, thereby achieving a degumming effect of collision and crushing, significantly optimizing the degumming effect on cemented hydrate particles and sand particles, and improving the degumming efficiency of cemented particles, which is beneficial to improving the recovery rate of natural gas hydrates.

[0041] 2. The marine hydrate cementing particle collision debonding and separation device of the present invention utilizes the energy of the hydrate slurry returned during the hydrate exploitation process, and can obtain the required pressure fluctuation through ingenious structural design without the need for additional pressure source or power source, thereby significantly improving the operability of collision debonding and avoiding the problem of bulky and bloated device that is inconvenient to put into the well.

[0042] 3. The marine hydrate agglomerated particle collision degumming and separation device of the present invention can make the hydrate slurry have a larger initial velocity in the cyclone, which is beneficial for the hydrate slurry to obtain a larger centrifugal force in the cyclone, improve the separation ability of hydrate particles and mud and sand particles, and at the same time, the centrifugal force can be used to degummed again, further improving the degumming ability of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings described herein are used to provide a further understanding of the embodiments of the present invention, constitute a part of this application, and do not constitute a limitation of the embodiments of the present invention. In the drawings:

[0044] Figure 1 It is a schematic diagram of a driving shaft at the bottom of the stroke in a specific embodiment of the present invention;

[0045] Figure 2 It is a schematic diagram of a driving shaft at the top of the stroke in a specific embodiment of the present invention;

[0046] Figure 3 It is a cross-sectional view of a throttling sleeve in a specific embodiment of the present invention.

[0047] Marks and corresponding parts names in the attached drawings:

[0048] 1-upper outer tube, 2-double-layer pipe joint, 201-downward flow channel, 202-upward flow channel, 203-sand discharge flow channel, 3-lower outer tube, 4-lower joint, 5-lower inner tube, 6-glue breaking sleeve, 601-jet hole, 7-first sealing ring, 8-driving shaft, 9-middle joint, 10-first elastic member, 11-piston head, 12-middle inner tube, 13-second sealing ring, 14-upper inner tube, 15-third sealing ring, 16-fourth sealing ring, 17-inner sleeve, 1701-pressure relief hole, 18-second elastic member, 19-throttling sleeve, 1901-throttling hole, 20-limiting sleeve, 21-suspension joint, 22-separator, 2201-tangential inlet, 2202-overflow port, 2203-bottom flow port, 23-separator sleeve, 24-upper joint. DETAILED DESCRIPTION

[0049] In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the examples and the accompanying drawings. The schematic embodiments of the present invention and the description thereof are only used to explain the present invention and are not intended to limit the present invention. In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inside", "outside", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is 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 cannot be understood as limiting the scope of protection of the present application.

[0050] Embodiment 1:

[0051] like Figure 1 and Figure 2The device for separating marine hydrate cemented particles by collision and gel breaking is shown, comprising a lower outer tube 3, an inner tube assembly located inside the lower outer tube 3, the inner tube assembly comprising a lower inner tube 5; a gel breaking sleeve 6 is arranged inside the lower inner tube 5, the bottom of the gel breaking sleeve 6 is closed, a plurality of radially opposite jet holes 601 are provided on the side wall of the gel breaking sleeve 6, and an annulus is provided between the gel breaking sleeve 6 and the lower inner tube 5; and a driving mechanism for slidingly fitting a driving shaft 8 inside the gel breaking sleeve 6 and driving the driving shaft 8 to perform axial reciprocating motion is also included. The outer diameter of the driving shaft 8 is equal to the inner diameter of the gel breaking sleeve 6.

[0052] When the driving shaft 8 is at the top of the stroke, all the jet holes 601 are connected to the inside of the rubber-breaking sleeve 6;

[0053] When the driving shaft 8 is located at the bottom of the stroke, part of the jet holes 601 are not connected to the inside of the rubber breaking sleeve 6 .

[0054] The inner layer pipe assembly in this embodiment further includes an intermediate joint 9 connected above the lower inner layer pipe 5, a middle inner layer pipe 12 connected above the intermediate joint 9, an upper inner layer pipe 14 connected above the middle inner layer pipe 12, and a hanging joint 21 connected above the upper inner layer pipe 14;

[0055] The driving mechanism includes a piston head 11 axially slidingly fitted in the middle inner layer tube 12, a first elastic member 10 connected between the piston head 11 and the intermediate joint 9, and an excitation component for generating pressure fluctuations inside the middle inner layer tube 12 and in the top space of the piston head 11; the piston head 11 is connected to the driving shaft 8.

[0056] The excitation assembly in this embodiment includes an inner sleeve 17 arranged inside the upper inner tube 14, a throttling sleeve 19 axially slidingly fitted in the inner sleeve 17, and a second elastic member 18 connected between the throttling sleeve 19 and the inner sleeve 17, and the throttling sleeve 19 is used to generate a throttling pressure drop from bottom to top.

[0057] In the present embodiment, the first elastic member 10 and the second elastic member 18 are preferably disc springs.

[0058] In addition, a pressure relief annulus is provided between the inner sleeve 17 and the upper inner pipe 14 ; a plurality of pressure relief holes 1701 are provided on the side wall of the inner sleeve 17 , and the pressure relief holes 1701 are connected to the pressure relief annulus, and the pressure relief annulus is connected to the interior of the suspension joint 21 .

[0059] When the throttling sleeve 19 is at the top of the stroke, the pressure relief hole 1701 is connected to the interior of the inner sleeve 17;

[0060] When the throttling sleeve 19 is located at the bottom of the stroke, the pressure relief hole 1701 is not connected to the interior of the inner sleeve 17 .

[0061] When this embodiment is used, both ends of the device can be connected to the existing natural gas hydrate production pipe string, and the gel breaking and separation device of this application only needs to be above the downhole power drill. Preferably, the gel breaking and separation device of this application can be as close to the downhole power drill as possible.

[0062] In a more preferred embodiment, the throttling sleeve 19 is as follows Figure 3 As shown, the interior includes a main cavity 1903, a variable diameter cavity 1902, a throttling hole 1901 and a variable diameter hole 1904 which are connected in sequence from bottom to top; the inner diameter of the throttling hole 1901 is smaller than the inner diameter of the main cavity 1903; the inner diameter of the variable diameter cavity 1902 gradually decreases from bottom to top; the inner diameter of the variable diameter hole 1904 gradually increases from top to bottom.

[0063] In a more preferred embodiment: a first sealing ring 7 is arranged between the rubber breaking sleeve 6 and the driving shaft 8; a second sealing ring 13 is arranged between the piston head 11 and the middle inner tube 12; a third sealing ring 15 is arranged between the inner sleeve 17 and the upper inner tube; and a fourth sealing ring 16 is arranged between the inner sleeve 17 and the throttling sleeve.

[0064] Embodiment 2:

[0065] A marine hydrate cementing particle collision debonding and separation device, based on Example 1, further comprises a double-layer pipe joint 2 connected to the lower outer layer pipe 3 and the top of the hanging joint 21, an upper outer layer pipe 1 connected above the double-layer pipe joint 2 and a separator sleeve 23, wherein the separator sleeve 23 is located inside the upper outer layer pipe 1; a downward flow channel 201 and an upward flow channel 202 are arranged in the double-layer pipe joint 2;

[0066] The top end of the downward flow channel 201 is connected to the annulus between the upper outer layer pipe 1 and the separator sleeve 23, and the bottom end of the downward flow channel 201 is connected to the annulus between the lower outer layer pipe 3 and the suspension joint 21;

[0067] The top end of the upward flow channel 202 is communicated with the interior of the separator sleeve 23 , and the bottom end of the upward flow channel 202 is communicated with the interior of the suspension joint 21 .

[0068] This embodiment also includes an upper joint 24 connected to the top of the separator sleeve 23 and a cyclone 22 arranged inside the separator sleeve 23; a tangential inlet 2201 is arranged on the side of the cyclone 22, an overflow port 2202 is arranged on the top, and an underflow port 2203 is arranged on the bottom, the tangential inlet 2201 is communicated with the interior of the separator sleeve 23, the overflow port 2202 runs through the upper joint 24, and the underflow port 2203 is connected to the sand discharge channel 203, and the sand discharge channel 203 is located in the double-layer pipe joint 2 and extends to the side wall of the double-layer pipe joint 2.

[0069] In addition, the outer diameter of the cyclone 22 gradually decreases from top to bottom.

[0070] Embodiment 3:

[0071] A marine hydrate cementing particle collision debonding and separation device, based on Example 2, its working process includes:

[0072] In the initial state without pump on, if Figure 2 As shown, the push shaft 8 is located at the top end of the stroke and the throttle sleeve 19 is located at the bottom end of the stroke.

[0073] After the wellhead pump is started, the high-pressure fluid is pumped from top to bottom to the annulus between the upper outer layer pipe 1 and the upper joint 24, enters the annulus between the lower outer layer pipe 3 and the inner layer pipe assembly through the downward flow channel 201 inside the double-layer pipe joint 2, and continues to flow downward until it enters the downhole power drill, causing the downhole power drill to rotate, and synchronously performing high-pressure jet crushing on the seabed hydrate during the drilling process.

[0074] The hydrate slurry obtained by drilling and high-pressure jet crushing enters the lower joint 4 under the action of lifting, and then enters the annulus between the lower inner layer pipe 5 and the rubber-breaking sleeve 6, enters the hollow flow channel inside the rubber-breaking sleeve 6 through the jet hole 601 of the rubber-breaking sleeve 6, and then passes through the hollow flow channel inside the push shaft 8, the hollow flow channel inside the piston head 11, the hollow flow channel inside the middle inner layer pipe 12, the hollow flow channel inside the inner sleeve 17, the hollow flow channel inside the throttling sleeve 19 and the hollow flow channel inside the hanging joint 21 in turn, and then enters the separator sleeve 23 through the upward flow channel 202 of the double-layer pipe joint 2, and then enters the separator 22 through the tangential inlet 2201. The separated mud and sand enter the sand discharge flow channel 203 through the bottom flow port 2203 and are discharged, and the separated hydrate enters the internal flow channel of the upper joint 24 through the overflow port 2202 and continues to be transported upward to the next link.

[0075] In the above process, the following collision and gel breaking process is automatically completed:

[0076] When the upward-returning hydrate slurry passes through the throttling sleeve 19, a pressurization area is formed at the lower end of the throttling hole 1901 and a pressure drop area is formed at the upper end of the throttling hole 1901 due to the throttling pressure reduction, resulting in a pressure difference between the upper and lower end faces of the throttling sleeve 19, and the high-pressure fluid at the lower end pushes the throttling sleeve 19 to move upward and compresses the second elastic member 18; at the same time, the high-pressure fluid pushes the piston head 11 to move downward, and the piston head 11 pushes the driving shaft 8 downward to move and compress the first elastic member 10, pushing the driving shaft 8 to press against the inner wall of the rubber-breaking sleeve 6 downward to squeeze the rubber-breaking sleeve 6 cavity; during this process, the throttling sleeve 19 always blocks the communication between the pressure relief hole 1701 and the inside of the inner sleeve 17.

[0077] When the throttle sleeve 19 continues to move upward to the top of the stroke, the bottom end of the throttle sleeve 19 moves to above the pressure relief hole 1701. Figure 1 As shown, at this time, the pressure relief hole 1701 is connected to the inside of the inner sleeve 17, the area below the throttling sleeve 19 is depressurized, and the high-pressure fluid returns through the pressure relief hole 1701 and the pressure relief annulus; therefore, the pressure difference between the upper and lower parts of the throttling sleeve 19 disappears rapidly, and the compressed second elastic member 18 releases the elastic force, pushing the throttling sleeve 19 to move axially downward; at the same time, the compressed first elastic member 10 releases the elastic force, pushing the piston head 11 to drive the driving shaft 8 to move axially upward, and the driving shaft 8 moves upward against the inner wall of the breaking sleeve 6, forming a suction effect in the cavity of the breaking sleeve 6. Under the action of the suction force, the recovered hydrate slurry enters the hollow flow channel of the breaking sleeve 6 through the radial jet of the jet hole 601 of the breaking sleeve 6. Since the jet holes 601 are symmetrically arranged in the radial direction, the fluid jetting in will collide with each other, and under the action of the collision force, the breaking and dispersion of the hydrate cementing particles is achieved.

[0078] The above collision breaking process is circulated, and the driving shaft 8 can automatically realize axial reciprocating motion inside the breaking sleeve 6, so that the recovered hydrate slurry can continuously perform jet collision under the action of suction to achieve the collision breaking effect until the pump is stopped at the wellhead.

[0079] Those skilled in the art should understand that the up / top direction in this application refers to the direction toward the wellhead after the device enters the well; conversely, the down / bottom direction in this embodiment refers to the direction toward the bottom of the well after the device enters the well.

[0080] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

[0081] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In addition, the term "connected" used in this article can be directly connected or indirectly connected via other components without special explanation.

Claims

1. A marine hydrate cementing particle collision debonding and separation device, comprising a lower outer layer tube (3), and an inner layer tube assembly located inside the lower outer layer tube (3), characterized in that: The inner layer tube assembly comprises a lower inner layer tube (5); a rubber-breaking sleeve (6) is arranged inside the lower inner layer tube (5); the bottom of the rubber-breaking sleeve (6) is closed, and a plurality of radially opposite jet holes (601) are provided on the side wall of the rubber-breaking sleeve (6); an annulus is provided between the rubber-breaking sleeve (6) and the lower inner layer tube (5); and the assembly also comprises a driving mechanism which is slidably fitted in the rubber-breaking sleeve (6) to drive a driving shaft (8) to perform axial reciprocating motion.

2. The marine hydrate cementing particle collision debonding and separation device according to claim 1, characterized in that: The outer diameter of the driving shaft (8) is equal to the inner diameter of the rubber-breaking sleeve (6); When the driving shaft (8) is located at the top of the stroke, all the jet holes (601) are connected to the inside of the rubber-breaking sleeve (6); When the driving shaft (8) is located at the bottom of the stroke, part of the jet holes (601) are not connected to the inside of the rubber-breaking sleeve (6).

3. The marine hydrate cementing particle collision debonding and separation device according to claim 1, characterized in that: The inner layer pipe assembly further comprises an intermediate joint (9) connected above the lower inner layer pipe (5), and a middle inner layer pipe (12) connected above the intermediate joint (9); The driving mechanism comprises a piston head (11) axially slidingly fitted in the middle inner tube (12), a first elastic member (10) connected between the piston head (11) and the intermediate joint (9), and an excitation component for generating pressure fluctuations in the space inside the middle inner tube (12) and at the top of the piston head (11); the piston head (11) is connected to the driving shaft (8).

4. The marine hydrate cementing particle collision debonding and separation device according to claim 3 is characterized in that: The inner layer tube assembly further comprises an upper inner layer tube (14) connected above the middle inner layer tube (12); The excitation component comprises an inner sleeve (17) arranged inside the upper inner tube (14), a throttling sleeve (19) axially slidingly fitted inside the inner sleeve (17), and a second elastic member (18) connected between the throttling sleeve (19) and the inner sleeve (17), wherein the throttling sleeve (19) is used to generate a throttling pressure drop from bottom to top.

5. The marine hydrate cementing particle collision debonding and separation device according to claim 4, characterized in that: The throttling sleeve (19) comprises a main cavity (1903), a variable diameter cavity (1902), a throttling hole (1901) and a variable diameter hole (1904) which are connected in sequence from bottom to top; the inner diameter of the throttling hole (1901) is smaller than the inner diameter of the main cavity (1903); the inner diameter of the variable diameter cavity (1902) gradually decreases from bottom to top; and the inner diameter of the variable diameter hole (1904) gradually increases from top to bottom.

6. The marine hydrate cementing particle collision debonding and separation device according to claim 4, characterized in that: A pressure relief annulus is provided between the inner sleeve (17) and the upper inner tube (14); a plurality of pressure relief holes (1701) are provided on the side wall of the inner sleeve (17), and the pressure relief holes (1701) are connected to the pressure relief annulus; When the throttling sleeve (19) is located at the top of the stroke, the pressure relief hole (1701) is connected to the interior of the inner sleeve (17); When the throttling sleeve (19) is located at the bottom of the stroke, the pressure relief hole (1701) is not connected to the interior of the inner sleeve (17).

7. The marine hydrate cementing particle collision debonding and separation device according to claim 6, characterized in that: The inner layer pipe assembly further comprises a hanging joint (21) connected above the upper inner layer pipe (14); the pressure relief annulus is in communication with the interior of the hanging joint (21).

8. The marine hydrate cementing particle collision debonding and separation device according to claim 1, characterized in that: It also comprises a double-layer pipe joint (2) connected to the top of the lower outer layer pipe (3) and the inner layer pipe assembly, an upper outer layer pipe (1) connected above the double-layer pipe joint (2) and a separator sleeve (23), wherein the separator sleeve (23) is located inside the upper outer layer pipe (1); a downward flow channel (201) and an upward flow channel (202) are arranged inside the double-layer pipe joint (2); The top end of the downward flow channel (201) is connected to the annulus between the upper outer layer pipe (1) and the separator sleeve (23), and the bottom end of the downward flow channel (201) is connected to the annulus between the lower outer layer pipe (3) and the inner layer pipe assembly; The top end of the upward flow channel (202) is in communication with the interior of the separator sleeve (23), and the bottom end of the upward flow channel (202) is in communication with the interior of the inner layer pipe assembly.

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