Gas regulating device for shale oil alternating gas injection displacement and its delivery device

Abstract

The application discloses a shale oil alternate gas injection displacement gas adjusting device and a conveying device thereof. The shale oil alternate gas injection displacement gas adjusting device comprises a fixed pipe, a rotating connecting pipe and a conveying pipe. The one end cover of the fixed pipe is provided with a sealing cover, and the sidewall of the fixed pipe is provided with at least two gas conveying openings for conveying different kinds of gas. The one end of the conveying pipe is movably inserted into the rotating connecting pipe, the rotating connecting pipe is rotatably connected with the conveying pipe, and the other end is detachably connected with a mounting pipe for conveying gas to a shale layer. The rotating connecting pipe is provided with an opening on the circumferential side, the rotating connecting pipe is movably inserted into the fixed pipe and rotatably connected with the fixed pipe, so that the opening is communicated with one of the gas conveying openings, and the gas conveying openings can be conveniently switched. The carbon dioxide and the nitrogen can be communicated with different conveying openings, and the carbon dioxide conveying opening and the nitrogen conveying opening can be conveniently switched by rotating the rotating connecting pipe.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of shale oil displacement, and particularly relates to a gas adjusting device for shale oil alternating gas injection displacement and a conveying device thereof. BACKGROUND

[0002] Shale oil is rich in resources worldwide and has broad exploitation prospects. However, the use of horizontal wells and a large number of hydraulic fracturing measures greatly increases the cost of shale oil exploitation.

[0003] Through a large number of experiments and data simulation results, it is known that the injection of gas can greatly improve the recovery rate of shale oil. Since carbon dioxide has strong extraction ability on crude oil and strong adsorption in organic matter, carbon dioxide injection technology has become one of the effective means for efficient development of shale oil reservoirs. However, due to the use of carbon dioxide, the greenhouse effect is caused, and the use of carbon dioxide is limited. In order to reduce the use of carbon dioxide, carbon dioxide and nitrogen displacement of shale oil has become a hot spot in the current shale oil development.

[0004] When carbon dioxide and nitrogen are used to alternately displace shale oil, the delivery amount of carbon dioxide and nitrogen needs to be controlled, and therefore the delivery port of carbon dioxide and nitrogen needs to be switched in time according to the delivery amount ratio of carbon dioxide and nitrogen. In the related art, due to the difficulty in switching between the delivery port of carbon dioxide and the delivery port of nitrogen, the shale oil exploitation process is interrupted, and it is difficult to realize continuous exploitation of shale oil. SUMMARY

[0005] In order to solve the technical problem that the shale oil exploitation process is interrupted due to the difficulty in switching between the delivery port of carbon dioxide and the delivery port of nitrogen in the related art, the first aspect of the present application provides a gas adjusting device for shale oil alternating gas injection displacement, comprising:

[0006] A fixed pipe, one end of which is provided with a sealing cover, and at least two gas delivery ports for delivering different kinds of gas are formed in the side wall of the fixed pipe;

[0007] A rotating connection pipe, an opening is formed in the circumferential side of the rotating connection pipe, the rotating connection pipe is movably inserted into the fixed pipe and rotationally connected with the fixed pipe, so that the opening is in communication with one of the gas delivery ports;

[0008] A delivery pipe, one end of which is movably inserted into the end of the rotating connection pipe away from the fixed pipe, the rotating connection pipe is rotationally connected with the delivery pipe, and the other end is detachably connected with a mounting pipe for delivering the gas to a shale layer.

[0009] In some embodiments, the gas adjusting device for shale oil alternating gas injection displacement further comprises:

[0010] a driving member located at one side of the rotating connecting pipe;

[0011] a transmission member located between the driving member and the rotating connecting pipe, the driving member being in transmission connection with the rotating connecting pipe through the transmission member, so that the rotating connecting pipe rotates around the axis.

[0012] In some embodiments, the transmission member comprises:

[0013] a gear ring surrounding the rotating connecting pipe and fixedly connected with the rotating connecting pipe;

[0014] an adjusting gear located at one side of the gear ring and in meshing connection with the gear ring, the driving end of the driving member being connected with the adjusting gear.

[0015] In some embodiments, the shale oil alternating gas injection and displacement gas regulating device further comprises:

[0016] a sealing ring surrounding the rotating connecting pipe and located between the rotating connecting pipe and the fixed pipe, the sealing ring being provided with a through hole corresponding to the opening.

[0017] In some embodiments, one end of the conveying pipe inserted into the rotating connecting pipe is provided with a limiting member along the radial direction of the conveying pipe; the shale oil alternating gas injection and displacement gas regulating device further comprises:

[0018] a movable plug surrounding the conveying pipe and movably connected with the limiting member, the peripheral wall of the movable plug being in abutment with the inner side wall of the rotating connecting pipe;

[0019] a resilient member located in the rotating connecting pipe, one end of the resilient member being in abutment with the side of the movable plug away from the limiting member, and the other end being in abutment with the inner side wall of the rotating connecting pipe.

[0020] In some embodiments, the limiting member is provided with a limiting groove along the peripheral direction of the conveying pipe, the movable plug is provided with a limiting protrusion, and the limiting groove is movably clamped in the limiting protrusion; or, the limiting member is provided with a limiting protrusion along the peripheral direction of the conveying pipe, and the movable plug is provided with a limiting groove, the limiting protrusion being movably clamped in the limiting groove.

[0021] In some embodiments, the shale oil alternating gas injection and displacement gas regulating device further comprises:

[0022] a connecting shaft located in the rotating connecting pipe and in rotational connection with the rotating connecting pipe;

[0023] a vane fixedly connected with one end of the connecting shaft and corresponding to the opening.

[0024] A first bevel gear is arranged around the periphery of the other end of the connecting shaft and is fixedly connected with the connecting shaft;

[0025] A rotating shaft is rotatably connected with the rotating connecting pipe, and the axis of the rotating shaft is parallel to the axis of the rotating connecting pipe;

[0026] A second bevel gear is arranged around the periphery of the rotating shaft and is fixedly connected with the rotating shaft, and the second bevel gear is meshingly connected with the first bevel gear;

[0027] A stirring blade is arranged around the periphery of the rotating shaft and is fixedly connected with the rotating shaft.

[0028] In some embodiments, the shale oil alternating gas injection and displacement gas regulating device further comprises:

[0029] A connecting rod is connected with the inner wall of the fixed pipe at one end and is provided with a mounting groove at the other end;

[0030] A bearing is sleeved in the mounting groove, the connecting rod is sleeved in the bearing, and the impeller and the first bevel gear are respectively located on the two sides of the bearing.

[0031] In some embodiments, the shale oil alternating gas injection and displacement gas regulating device further comprises:

[0032] A sleeve shaft is located in the fixed pipe and is mounted on the sealing cover, and one end of the rotating shaft is movably sleeved in the sleeve shaft;

[0033] A fixed plate is located in the fixed pipe and is fixedly connected with the inner wall of the fixed pipe, the fixed plate is provided with an adapter hole, the rotating shaft is movably sleeved in the adapter hole, and the fixed plate is clamped between the second bevel gear and the stirring blade.

[0034] A second aspect of the present application provides a shale oil alternating gas injection and displacement gas delivery device, which comprises:

[0035] The shale oil alternating gas injection and displacement gas regulating device described above;

[0036] At least two gas storage barrels are respectively communicated with the gas delivery ports, and the number of the gas storage barrels is equal to the number of the gas delivery ports;

[0037] A stirring shaft is rotatably arranged in the gas storage barrel;

[0038] A stirring rod is located around the periphery of the stirring shaft and is fixedly connected with the stirring shaft.

[0039] According to one or more embodiments of the present application, a shale oil alternating gas injection displacement gas adjusting device and a delivery device thereof are provided. The shale oil alternating gas injection displacement gas adjusting device comprises a fixed pipe, a rotating connecting pipe and a delivery pipe. One end of the fixed pipe is provided with a sealing cover, and at least two gas delivery ports for delivering different kinds of gas are formed in the sidewall of the fixed pipe. One end of the delivery pipe is movably inserted into the rotating connecting pipe away from the fixed pipe, the rotating connecting pipe is rotatably connected with the delivery pipe, and the other end is detachably connected with a mounting pipe for delivering gas to a shale layer. An opening is formed in the circumferential side of the rotating connecting pipe, the rotating connecting pipe is movably inserted into the fixed pipe and rotatably connected with the fixed pipe, so that the opening is in communication with one of the gas delivery ports. By rotating the rotating connecting pipe, the opening can be in communication with one of the gas delivery ports, so that the gas delivery ports can be conveniently switched. Carbon dioxide and nitrogen can be respectively in communication with different delivery ports, and by rotating the rotating connecting pipe, the delivery port of carbon dioxide and the delivery port of nitrogen can be conveniently switched. BRIEF DESCRIPTION OF DRAWINGS

[0040] Figure 1 A structural schematic diagram of a shale oil alternating gas injection displacement gas adjusting device in one or more embodiments of the present application is shown.

[0041] Figure 2 A structural schematic diagram of a shale oil alternating gas injection displacement gas adjusting device in one or more embodiments of the present application is shown. Figure 1 A sectional view along the axis is shown.

[0042] Figure 3 A structural schematic diagram of a shale oil alternating gas injection displacement gas adjusting device (including an adjusting motor, an adjusting gear and a gear ring) in one or more embodiments of the present application is shown.

[0043] Figure 4 A structural schematic diagram of a shale oil alternating gas injection displacement gas adjusting device (including an adjusting motor, an adjusting gear and a gear ring) in one or more embodiments of the present application is shown.

[0044] Figure 5 A structural schematic diagram of a shale oil alternating gas injection displacement gas adjusting device (including an adjusting motor, an adjusting gear and a gear ring) in one or more embodiments of the present application is shown.

[0045] Figure 6 A structural schematic diagram of a shale oil alternating gas injection displacement gas adjusting device (including an adjusting motor, an adjusting gear and a gear ring) in one or more embodiments of the present application is shown. Figure 5 A sectional view along the axis is shown.

[0046] Figure 7 A structural schematic diagram of a shale oil alternating gas injection displacement gas adjusting device (including an adjusting motor, an adjusting gear and a gear ring) in one or more embodiments of the present application is shown. Figure 6 An enlarged schematic diagram of A in FIG. 6 is shown.

[0047] Explanation of reference signs:

[0048] 1, bottom plate; 2, support seat; 3, first barrel; 4, second barrel; 5, stirring motor; 6, stirring shaft; 7, stirring rod; 8, flow guide pipe; 9, fixed pipe; 91, gas inlet; 92, sealing cover; 10, control valve; 11, sleeve shaft; 12, rotating shaft; 13, second bevel gear; 14, stirring blade; 15, fixed plate; 161, rotating connection pipe; 16, connection pipe; 17, extension pipe; 171, opening; 18, sealing ring; 19, via hole; 20, connecting rod; 21, bearing; 22, connecting shaft; 23, impeller; 24, first bevel gear; 25, gear ring; 26, spring; 27, movable plug; 28, conveying pipe; 29, limiting groove; 30, mounting pipe; 31, flange; 32, bolt; 33, nut; 34, adjusting motor; 35, adjusting gear. DETAILED DESCRIPTION

[0049] In order for those skilled in the art to which the present application belongs to more clearly understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of protection of the present application.

[0050] Shale oil has abundant resources worldwide and has broad exploitation prospects. However, the use of horizontal wells and a large number of hydraulic fracturing measures greatly increases the cost of shale oil exploitation.

[0051] Through a large number of experiments and data simulation results, it is known that the injection of gas can greatly improve the recovery rate of shale oil. Since carbon dioxide has strong extraction ability for crude oil and strong adsorption in organic matter, carbon dioxide injection technology has become one of the effective means for efficient development of shale oil reservoirs. However, the use of carbon dioxide will produce a greenhouse effect, which limits the use of carbon dioxide. In order to reduce the use of carbon dioxide, carbon dioxide and nitrogen displacement of shale oil has become a hot spot for shale oil development at present.

[0052] The injection amount adjustment expression disclosed in the patent document "CN202011021630.9 A shale oil CO2 / N2 alternate displacement injection amount simulation analysis method" can be used for reference to adjust the injection amount of CO2 / N2 in the process of shale oil CO2 / N2 alternate displacement mining, improve the total efficiency of CO2 / N2 oil displacement in the actual mining process, and further improve the recovery rate of shale oil.

[0053] When carbon dioxide and nitrogen are used to alternately displace shale oil, the delivery amount of carbon dioxide and nitrogen needs to be controlled, and therefore the delivery ports of carbon dioxide and nitrogen need to be switched in time according to the delivery amount ratio of carbon dioxide and nitrogen, so as to reduce the use amount of carbon dioxide. However, when carbon dioxide and nitrogen are used to alternately displace, the delivery ports of carbon dioxide and nitrogen need to be alternately switched, and there is difficulty in switching the delivery ports of carbon dioxide and nitrogen, and it is difficult to control the delivery amount of carbon dioxide and nitrogen during gas injection, which brings inconvenience to the delivery of carbon dioxide and nitrogen, and causes the shale oil exploitation process to be interrupted, and it is difficult to realize continuous exploitation of shale oil.

[0054] In order to solve the technical problem that the shale oil exploitation process is interrupted due to the difficulty in switching the delivery ports of carbon dioxide and nitrogen in the related art, a first aspect of the present application provides a gas adjusting device for shale oil alternate gas injection displacement, please refer to Figures 1-2 The gas adjusting device for shale oil alternate gas injection displacement at least comprises a fixed pipe 9, a rotating connection pipe 161 and a delivery pipe 28.

[0055] The fixed pipe 9 is provided in a tubular shape, and one end of the fixed pipe 9 is provided with a sealing cover 92, and the other end of the fixed pipe 9 is provided as an open end. The side wall of the fixed pipe 9 is provided with at least two gas delivery ports 91 for delivering different kinds of gas, and the gas delivery ports 91 are provided at the same position along the axis of the fixed pipe 9.

[0056] The rotating connection pipe 161 is movably inserted into the fixed pipe 9 through the open end of the fixed pipe 9, and the peripheral side wall of the rotating connection pipe 161 is spaced apart from the inner side wall of the fixed pipe 9, and the rotating connection pipe 161 can be rotated relative to the fixed pipe 9 by rotating the rotating connection pipe 161, so as to realize the rotating connection between the rotating connection pipe 161 and the fixed pipe 9.

[0057] The peripheral side of the rotating connection pipe 161 is provided with an opening 171, and when the rotating connection pipe 161 is inserted into the fixed pipe 9, the opening 171 and the gas delivery port 91 on the fixed pipe 9 are located at the same position along the axis of the fixed pipe 9, and then the opening 171 and one of the gas delivery ports 91 are communicated by rotating the rotating connection pipe 161, so that the gas delivery ports 91 can be switched more conveniently.

[0058] In order to improve the external appearance of the rotating connection of the fixed pipe 9, the rotating connection pipe 161 and the conveying pipe 28, the rotating connection pipe 161 can include a connecting pipe 16 and an extension pipe 17, the pipe diameter of the connecting pipe 16 is larger than that of the extension pipe 17, and the axis of the connecting pipe 16 is collinear with that of the extension pipe 17, and the connecting position of the connecting pipe 16 and the extension pipe 17 is stepped. The pipe diameter of the connecting pipe 16 is equal to that of the fixed pipe 9, and the pipe diameter of the fixed pipe 9 is larger than that of the extension pipe 17. The end of the extension pipe 17 away from the connecting pipe 16 is inserted into the fixed pipe 9, and the conveying pipe 28 can be inserted into the connecting pipe 16 away from the opening of the extension pipe 17. The pipe diameter of the conveying pipe 28 can be equal to that of the extension pipe 17. In this way, by setting different sizes between the pipe diameters of the fixed pipe 9, the connecting pipe 16, the extension pipe 17 and the conveying pipe 28, the external appearance of the rotating connection of the fixed pipe 9, the rotating connection pipe 161 and the conveying pipe 28 can be improved to a certain extent.

[0059] One end of the conveying pipe 28 is movably inserted into the end of the connecting pipe 16 away from the extension pipe 17, and the other end of the conveying pipe 28 is rotatably connected with the connecting pipe 16. The other end of the conveying pipe 28 is detachably connected with the installation pipe 30 for conveying gas to the shale layer (see Figures 5-7 ). The detachable connection between the conveying pipe 28 and the installation pipe 30 can be achieved by bolts 32 or other means such as clamping, and the specific detachable connection mode is not limited in the application and can be set according to actual needs.

[0060] The installation pipe 30 extends into a deep oil well. In order to ensure the stability of the installation pipe 30 in conveying displacement gas and to ensure the service life of the installation pipe 30, the installation pipe 30 does not rotate in the oil well. The conveying pipe 28 and the installation pipe 30 are fixedly connected by the bolts 32, so that the position between the conveying pipe 28 and the installation pipe 30 is fixed. At the same time, since the gas conveying device connected with the gas conveying port 91 of the fixed pipe 9 needs to continuously convey gas into the fixed pipe 9, and the position of the gas conveying device is relatively fixed, the position of the fixed pipe 9 can be relatively fixed. Since the positions of the fixed pipe 9 and the conveying pipe 28 are fixed, and the extension pipe 17 is rotatably connected with the fixed pipe 9, and the connecting pipe 16 is also rotatably connected with the conveying pipe 28, the opening 171 on the extension pipe 17 can be corresponded to one of the gas conveying ports 91 on the side wall of the fixed pipe 9 by rotating the rotating connection pipe 161. In this way, different gas conveying ports 91 can be switched more conveniently.

[0061] In the shale oil alternative gas injection displacement process, carbon dioxide and nitrogen can be delivered by different gas delivery ports 91. By rotating the connecting pipe 161, the opening 171 on the extension pipe 17 can be matched with the carbon dioxide delivery port 91 or the nitrogen delivery port 91 on the side wall of the fixed pipe 9, so that carbon dioxide or nitrogen can be delivered to the position in the shale layer where shale oil displacement is needed through the fixed pipe 9, the extension pipe 17, the connecting pipe 16 and the delivery pipe 28, and then through the mounting pipe 30. In this way, by rotating the connecting pipe 161 to switch the carbon dioxide delivery port 91 and the nitrogen delivery port 91, the convenience of switching the carbon dioxide delivery port 91 and the nitrogen delivery port 91 can be improved.

[0062] In order to improve the rotation convenience of the connecting pipe 16, please refer to Figure 3 , the shale oil alternative gas injection displacement gas adjusting device further comprises a driving member and a transmission member. The driving member is located on one side of the rotating connecting pipe 161. The transmission member is located between the driving member and the rotating connecting pipe 161. The driving member is in transmission connection with the rotating connecting pipe 161 through the driving member, so as to rotate the rotating connecting pipe 161 around the axis.

[0063] Specifically, please refer to Figure 3 , the transmission member comprises a gear ring 25 and an adjusting gear 35. The gear ring 25 is arranged around the side of the connecting pipe 16 and is fixedly connected with the connecting pipe 16. The adjusting gear 35 is located on one side of the gear ring 25 and is in meshing connection with the gear ring 25. The driving end of the driving member is connected with the adjusting gear 35. The driving member can be an adjusting motor 34. The output end of the adjusting motor 34 is fixedly connected with the adjusting gear 35. The adjusting gear 35 is in meshing connection with the gear ring 25. By rotating the adjusting gear 35 through the adjusting motor 34, the adjusting gear 35 can drive the gear ring 25 to rotate, and then drive the connecting pipe 16 and the extension pipe 17 to stably rotate. In this way, the connecting pipe 16 and the extension pipe 17 can be automatically rotated through the adjusting motor 34, realizing the automation of the rotation of the connecting pipe 16. Since the bottom end of the connecting pipe 16 is limited by the delivery pipe 28, and the top of the extension pipe 17 is limited by the fixed pipe 9, the connecting pipe 16 and the extension pipe 17 can stably rotate between the delivery pipe 28 and the fixed pipe 9.

[0064] In order to improve the sealing performance of the rotation connection between the extension pipe 17 and the fixed pipe 9, please refer to Figures 1-3 , the shale oil alternative gas injection displacement gas adjusting device further comprises a sealing ring 18. The sealing ring 18 is arranged in a circular ring structure and is sleeved around the side of the top end of the extension pipe 17. The sealing ring 18 is located between the extension pipe 17 and the fixed pipe 9. The surface of the extension pipe 17 is fixedly connected with the sealing ring 18, so that the sealing ring 18 is in sealing contact with the inner wall of the fixed pipe 9.

[0065] The sealing ring 18 is provided with a through hole 19 at a position corresponding to the opening 171. Thus, by rotating the connecting pipe 161, the opening 171 on the extension pipe 17 and the through hole 19 on the sealing ring 18 can be communicated with the gas outlet 91 for carbon dioxide or the gas outlet 91 for nitrogen on the side wall of the fixed pipe 9.

[0066] The sealing ring 18 is used to improve the sealing performance between the extension pipe 17 and the fixed pipe 9, so that the extension pipe 17 can be sealed and rotated inside the fixed pipe 9, and gas leakage between the fixed pipe 9 and the extension pipe 17 can be prevented. It should be noted that the sealing ring 18 can also be fixedly connected with the inner wall of the fixed pipe 9, so that the sealing ring 18 is tightly sealed with the surface of the extension pipe 17.

[0067] By adjusting the motor 34 to drive the connecting pipe 16 and the extension pipe 17 to rotate, the extension pipe 17 rotates inside the fixed pipe 9, the sealing ring 18 on the surface of the extension pipe 17 is tightly sealed and rotated on the inner wall of the fixed pipe 9, and effective sealing is achieved at the connection between the fixed pipe 9 and the extension pipe 17.

[0068] In order to ensure that the connecting pipe 16 rotates relative to the conveying pipe 28 while ensuring the sealing performance of the rotating connection between the connecting pipe 16 and the conveying pipe 28, please refer to Figures 2-3 , the end of the conveying pipe 28 inserted into the connecting pipe 16 is provided with a limiting piece (not shown in the figure) along the radial direction of the conveying pipe 28. The shale oil alternating gas injection and displacement gas conveying device further comprises a movable plug 27 and an elastic piece (not shown in the figure). The movable plug 27 is arranged around the conveying pipe 28 and is movably connected with the limiting piece, and the connecting pipe 16 is slidably connected with the movable plug 27 through the limiting piece. The inside of the connecting pipe 16 is slidably connected with the movable plug 27, and the peripheral wall of the movable plug 27 is tightly connected with the inner side wall of the rotating connecting pipe 161. The stepped structure between the connecting pipe 16 and the extension pipe 17 forms an abutting portion, the movable plug 27 abuts against the abutting portion through the spring 26, and the movable plug 27 is tightly connected with the peripheral edge of the top of the conveying pipe 28.

[0069] The elastic piece is located in the rotating connecting pipe 161, and one end of the elastic piece abuts against the side of the movable plug 27 away from the limiting piece, and the other end abuts against the inner side wall of the rotating connecting pipe 161. The elastic piece can be a spring 26, which pushes the movable plug 27 to move along the axis of the connecting pipe 16, so that the movable plug 27 abuts against the limiting piece to achieve stable abutment with the conveying pipe 28. In this way, the relative rotation between the connecting pipe 16 and the conveying pipe 28 is ensured, and the movable plug 27 is tightly abutted with the inner wall of the connecting pipe 16, which is conducive to improving the sealing performance between the conveying pipe 28 and the connecting pipe 16, and preventing gas leakage.

[0070] Please refer to Figure 3The limiting member is provided with a limiting groove 29 along the circumferential side of the conveying pipe 28, and the movable plug 27 is provided with a limiting protrusion (not shown in the figure), and the limiting groove 29 is movably clamped in the limiting protrusion. The limiting groove 29 is located at the top of the conveying pipe 28, and the limiting groove 29 is embeddedly connected with the movable plug 27, and the movable plug 27 has a U-shaped structure in cross section. The spring 26 in the connecting pipe 16 pushes the movable plug 27 to move, so that the movable plug 27 abuts against the limiting groove 29 at the top of the conveying pipe 28. The movable plug 27 is moved in the connecting pipe 16 by the elastic pushing of the spring 26, so that the limiting protrusion of the movable plug 27 is embedded in the limiting groove 29 of the conveying pipe 28, and the stable fitting between the movable plug 27 and the conveying pipe 28 is realized. At the same time, the movable plug 27 is deformed by the extrusion force generated by the spring 26, so that the movable plug 27 abuts against the inner wall of the connecting pipe 16, and the effective sealing of the connecting position of the connecting pipe 16 and the conveying pipe 28 is realized, which is beneficial to improve the sealing performance, prevent the leakage of displacement gas, and is beneficial to ensure the safety in production.

[0071] In some embodiments, the limiting member is provided with a limiting protrusion along the circumferential side of the conveying pipe 28, and the movable plug 27 is provided with a limiting groove, and the limiting protrusion is movably clamped in the limiting groove. The movable plug 27 is moved in the connecting pipe 16 by the elastic pushing of the spring 26, so that the limiting groove of the movable plug 27 is embedded in the limiting protrusion of the conveying pipe 28, and the stable fitting between the movable plug 27 and the conveying pipe 28 is realized.

[0072] When alternatingly injecting gas into the shale layer, the rotation of the connecting pipe 16 and the extension pipe 17 can realize the switching of the gas conveying port 91 conveying different gases. The use of the sealing ring 18 and the movable plug 27 can ensure the effective sealing of the pipeline connection position, avoid the leakage of gas, and is beneficial to improve the safety in production. At the same time, the quick switching of the gas conveying port 91 conveying different gases can be realized, which is beneficial to the continuous injection of displacement gas during the shale oil exploitation, and realizes the continuous exploitation of the shale oil.

[0073] In order to improve the oil production rate of shale oil, when using carbon dioxide or nitrogen to displace shale oil, the carbon dioxide and nitrogen need to be mixed with additives. The additives are used to improve the efficiency of shale oil exploitation, such as oil displacement agent, increase the foaming property of crude oil, block gas channeling, and improve the oil recovery rate.

[0074] In order to improve the oil recovery rate, the additives need to be fully mixed with carbon dioxide or nitrogen. When carbon dioxide or nitrogen is used to displace shale oil, it can directly contact with crude oil, increase the foaming property of crude oil, block gas channeling, and improve the oil recovery rate.

[0075] In order to fully mix carbon dioxide or nitrogen with additives, please refer to Figures 3-4The shale oil alternate gas injection displacement gas adjusting device further comprises a connecting shaft 22, an impeller 23, a first bevel gear 24, a rotating shaft 12, a second bevel gear 13 and stirring blades 14. The connecting shaft 22 is located in the extension pipe 17 and is rotationally connected with the extension pipe 17. The impeller 23 is fixedly connected with one end of the connecting shaft 22 and corresponds to the opening 171. The first bevel gear 24 is arranged around the other end of the connecting shaft 22. The rotating shaft 12 is rotationally connected with the extension pipe 17, and the axis of the rotating shaft 12 is parallel to the axis of the extension pipe 17. The second bevel gear 13 is sleeved around the rotating shaft 12 and is fixedly connected with the rotating shaft 12, and the second bevel gear 13 is meshingly connected with the first bevel gear 24. The stirring blades 14 are arranged around the rotating shaft 12 and are fixedly connected with the rotating shaft 12. In this way, the displacement gas flows into the extension pipe 17 through the through hole 19 on the sealing ring 18 and the opening 171 on the extension pipe 17 from the gas inlet 91, and the flow of the gas can make the impeller 23 rotate, the rotation of the impeller 23 drives the connecting shaft 22 to rotate, the first bevel gear 24 and the second bevel gear 13 are meshingly connected and transmitted, the second bevel gear 13 drives the rotating shaft 12 to rotate, and then the stirring blades 14 fixedly connected with the rotating shaft 12 rotate. When the gas passes through the stirring blades 14, the additives and carbon dioxide or nitrogen are fully mixed under the stirring action of the stirring blades 14.

[0076] In order to improve the rotation smoothness of the rotating shaft 12, the shale oil alternate gas injection displacement gas adjusting device further comprises a connecting rod 20 and a bearing 21. One end of the connecting rod 20 is connected with the inner wall of the fixed pipe 9, and the other end is provided with a mounting groove (not shown in the figure). A plurality of uniformly distributed connecting rods 20 are arranged in the extension pipe 17, the plurality of connecting rods 20 are fixedly connected and the end portions are arranged around the mounting groove, the bearing 21 is located in the mounting groove and is fixedly connected with the plurality of connecting rods 20. The connecting shaft 22 is sleeved in the bearing 21, the impeller 23 and the first bevel gear 24 are located on both sides of the bearing 21 respectively, the impeller 23 is distributed between the plurality of connecting rods 20, and the impeller 23 is correspondingly arranged on one side of the opening 171. The connecting shaft 22 is connected with the mounting groove through the bearing 21, which can improve the rotation smoothness of the connecting shaft 22 in the mounting groove.

[0077] In order to facilitate the rotation of the rotating shaft 12 in the extension pipe 17 and the connecting pipe 16, please refer to Figure 3 The shale oil alternate gas injection displacement gas adjusting device further comprises a sleeve shaft 11 and a fixed plate 15. The sleeve shaft 11 is located in the fixed pipe 9 and is mounted on the sealing cover 92, and one end of the rotating shaft 12 is movably sleeved in the sleeve shaft 11. The fixed plate 15 is located in the fixed pipe 9 and is fixedly connected with the inner wall of the fixed pipe 9. The fixed plate 15 is provided with an adapter hole (not shown in the figure), the rotating shaft 12 is movably sleeved in the adapter hole, and the fixed plate 15 is clamped between the second bevel gear 13 and the stirring blades 14.

[0078] The inner wall of the extension pipe 17 is fixedly connected with the bearing 21 through the connecting rod 20, the bearing 21 is fixedly connected with the connecting shaft 22, and the connecting shaft 22 is fixedly connected with the impeller 23 and the first bevel gear 24 at two ends respectively. The sealing cover 92 at the top end of the fixed pipe 9 is fixedly connected with the sleeve shaft 11, the sleeve shaft 11 is rotatably connected with the rotating shaft 12, the rotating shaft 12 is fixedly connected with the second bevel gear 13 and the stirring blade 14 at two ends respectively, and the second bevel gear 13 is meshingly connected with the first bevel gear 24. The impeller 23 is located at one side of the opening 171, and can be contacted with the impeller 23 during gas conveying, and the impeller 23 is driven to rotate by the thrust generated during gas conveying, and then the first bevel gear 24 is driven to rotate. The connecting rod 20 is fixedly connected with the bearing 21 in the extension pipe 17, so that the connecting shaft 22 can stably rotate in the bearing 21, and when the gas conveyed from the gas inlet 91 enters the inside of the fixed pipe 9, the gas can contact the impeller 23, and the impeller 23 drives the connecting shaft 22 and the first bevel gear 24 to rotate, so that the second bevel gear 13 and the rotating shaft 12 are driven to rotate.

[0079] The sealing cover 92 of the fixed pipe 9 is provided with the sleeve shaft 11, the sleeve shaft 11 is movably sleeved with the rotating shaft 12, the fixed plate 15 is fixedly connected with the inner wall of the fixed pipe 9, the fixed plate 15 is rotatably connected with the rotating shaft 12, and the fixed plate 15 is located between the second bevel gear 13 and the stirring blade 14. The rotating shaft 12 extends into the extension pipe 17 and the connecting pipe 16, and the stirring blade 14 connected to the bottom of the rotating shaft 12 can rotate in the extension pipe 17 and the connecting pipe 16. The sleeve shaft 11 can realize the rotation of the rotating shaft 12, and cooperates with the fixed plate 15 to enable the rotating shaft 12 to stably rotate in the fixed plate 15 and the sleeve shaft 11. During gas conveying, the impeller 23 drives the first bevel gear 24 to rotate through the connecting shaft 22, the first bevel gear 24 drives the second bevel gear 13 and the rotating shaft 12 to rotate at the same time, and then the stirring blade 14 at the bottom of the rotating shaft 12 is driven to rotate, so that the gas is uniformly mixed during conveying, which is beneficial to improve the displacement effect of the crude oil.

[0080] The second aspect of the present application provides a shale oil alternating gas injection displacement gas conveying device, please refer to Figures 5-7 The shale oil alternating gas injection displacement gas conveying device comprises the shale oil alternating gas injection displacement gas regulating device, the gas storage barrel, the stirring shaft 6 and the stirring rod 7.

[0081] The gas storage barrel is provided with at least two, and is communicated with the gas inlet 91 respectively, and the number of the gas storage barrels is equal to the number of the gas inlets 91. The stirring shaft 6 is rotatably arranged in the gas storage barrel, and the stirring rod 7 is located on the circumferential side of the stirring shaft 6 and is fixedly connected with the stirring shaft 6.

[0082] Please refer to Figures 5-7, two gas storage barrels can be first barrel 3 and second barrel 4 respectively, in order to facilitate the fixation of first barrel 3 and second barrel 4, shale oil alternating gas injection displacement gas delivery device also includes the bottom plate 1 and two support seats 2. First barrel 3 and second barrel 4 are placed in the bottom plate 1, the bottom plate 1 is fixedly installed with first barrel 3 and second barrel 4 through two support seats 2 respectively, two support seats 2 are used for supporting and fixing first barrel 3 and second barrel 4 respectively.

[0083] The bottom plate 1 is fixedly installed with two support seats 2, and the two support seats 2 are symmetrically distributed to the two sides of the bottom plate 1. The top of the two support seats 2 is fixedly connected with the first barrel 3 and the second barrel 4 respectively. The first barrel 3 and the second barrel 4 are respectively provided in a cylindrical structure, and the first barrel 3 and the second barrel 4 are respectively used for storing carbon dioxide and nitrogen for shale oil displacement.

[0084] In order to facilitate the communication of first barrel 3 and second barrel 4 with fixed pipe 9, shale oil alternating gas injection displacement gas delivery device also includes flow guide pipe 8, first barrel 3 and second barrel 4 bottom end respectively with flow guide pipe 8 through connection, two flow guide pipe 8 respectively with fixed pipe 9 on the gas inlet 91 for conveying different kinds of gas communication.

[0085] Flow guide pipe 8 is used for conveying gas in first barrel 3 and second barrel 4, and conveying gas to the inside of fixed pipe 9 through flow guide pipe 8, so as to realize stable conveying of displacement gas. The middle of the bottom plate 1 is fixedly connected with the conveying pipe 28, the connecting pipe 16 is rotatably connected with the inside of the conveying pipe 28, and the extension pipe 17 is rotatably connected with the inside of the fixed pipe 9. The connecting pipe 16 and the extension pipe 17 can realize the alternate conveying of different gases during gas conveying.

[0086] The number of flow guide pipes 8 is two, and the two flow guide pipes 8 are respectively located between first barrel 3 and fixed pipe 9 and between second barrel 4 and fixed pipe 9. The flow guide pipes 8 are symmetrically distributed to the two sides of the fixed pipe 9, and the two sides of the fixed pipe 9 are communicated with the bottom ends of the first barrel 3 and the second barrel 4 through the flow guide pipes 8. In order to more accurately control the amount of gas conveyed by first barrel 3 and second barrel 4 into fixed pipe 9 through flow guide pipe 8, flow guide pipe 8 can be communicated with control valve 10. The number of control valves 10 is two, and the two control valves 10 are respectively located on the two sides of the fixed pipe 9. The flow guide pipe 8 is used for conveying gas into the fixed pipe 9, and the control valve 10 is arranged on the flow guide pipe 8, which is used for adjusting the gas conveying amount and conveying pressure, so as to ensure the stable conveying of displacement gas.

[0087] Please refer to Figure 7The surface of the extension pipe 17 is fixedly connected with the sealing ring 18, and the extension pipe 17 is provided with an opening 171 on one side. The sealing ring 18 is provided with a through hole 19 on one side. The opening 171 and the through hole 19 can be circular structures, and the diameter of the opening 171 and the diameter of the through hole 19 are the same as the inner diameter of the flow guide pipe 8, so that the gas in the flow guide pipe 8 can be smoothly transported into the fixed pipe 9 through the opening 171 and the through hole 19.

[0088] Please refer to Figures 5-6 The first barrel body 3 is provided with a stirring motor 5 at the top. The output end of the stirring motor 5 is fixedly connected with the stirring shaft 6. The stirring shaft 6 is uniformly fixed with a plurality of stirring rods 7 on the side. The stirring motor 5 can drive the stirring shaft 6 to rotate in the first barrel body 3. When the stirring shaft 6 drives the stirring rod 7 to rotate, the gas and the additive in the first barrel body 3 are effectively mixed, so that the gas is transported into the fixed pipe 9 after being fully mixed with the additive.

[0089] The second barrel body 4 is also provided with a stirring motor 5 at the top. The output end of the stirring motor 5 is fixedly connected with the stirring shaft 6. The stirring shaft 6 is uniformly fixed with a plurality of stirring rods 7 on the side. The stirring motor 5 can drive the stirring shaft 6 to rotate in the second barrel body 4. When the stirring shaft 6 drives the stirring rod 7 to rotate, the gas and the additive in the second barrel body 4 are effectively mixed, so that the gas is transported into the fixed pipe 9 after being fully mixed with the additive.

[0090] When the gas is transported, the gas and the additive in the first barrel body 3 or the second barrel body 4 can be effectively mixed. When the gas is alternately injected in the connecting pipe 16 and the extension pipe 17, the gas and the additive are further fully mixed, which is beneficial to improve the effect of alternating injection displacement and ensure efficient exploitation of shale oil.

[0091] Please refer to Figures 6-7 The connecting pipe 16 is rotatably connected with the conveying pipe 28. The conveying pipe 28 is provided with a mounting pipe 30 at the bottom end. The mounting pipe 30 is fixedly connected with flanges 31 at adjacent ends. The flanges 31 are connected with each other. The edges of the flanges 31 are connected with bolts 32, and the ends of the bolts 32 are threadedly connected with nuts 33. The bottom plate 1 is installed at the wellhead of shale oil exploitation. The flanges 31 at the bottom end of the conveying pipe 28 are connected with the mounting pipe 30. The connection between the conveying pipe 28 and the mounting pipe 30 is realized by cooperation of the bolts 32 and the nuts 33, which is convenient for construction and can realize stable gas transportation.

[0092] The gas conveying device for shale oil alternating gas injection displacement in the application adopts the first barrel body 3 and the second barrel body 4 to realize the gas conveying during the alternating gas injection during the shale oil exploitation. The stable support of the first barrel body 3 and the second barrel body 4 is realized through the support seat 2, and the rotation of the stirring shaft 6 and the stirring rod 7 is driven by the stirring motor 5, so that the gas in the first barrel body 3 and the second barrel body 4 can be fully mixed with the additive. The gas is conveyed to the inside of the fixed pipe 9 through the flow guide pipe 8, and when the adjusting gear 35 is rotated by the adjusting motor 34, the adjusting gear 35 drives the gear ring 25, the connecting pipe 16 and the extension pipe 17 to rotate at the same time, so that the position of the opening 171 at the top of the extension pipe 17 changes. After the opening 171 corresponds to the flow guide pipe 8, the gas in the corresponding flow guide pipe 8 enters the fixed pipe 9.

[0093] When the gas is conveyed, the gas contacts the impeller 23 at the opening 171, drives the connecting shaft 22 to rotate at the bearing 21, drives the first bevel gear 24 to rotate through the connecting shaft 22, drives the second bevel gear 13 to rotate through the first bevel gear 24, drives the rotating shaft 12 to rotate in the sleeve shaft 11 and the fixed plate 15 through the second bevel gear 13, so that the rotating shaft 12 can drive the stirring blade 14 to rotate, so that the gas for displacement can be fully mixed and then enter the inside of the conveying pipe 28. The conveying pipe 28 and the mounting pipe 30 are connected through the flange 31, and the assembly and fixation between the conveying pipe 28 and the mounting pipe 30 are realized through the cooperation of the bolt 32 and the nut 33, so as to realize the conveying of the gas.

[0094] When the adjusting motor 34 drives the connecting pipe 16 and the extension pipe 17 to rotate, the extension pipe 17 rotates in the fixed pipe 9, the sealing ring 18 on the surface of the extension pipe 17 is attached to and sealed with the inner wall of the fixed pipe 9, and the effective sealing of the connection between the fixed pipe 9 and the extension pipe 17 is realized. The spring 26 in the connecting pipe 16 pushes the movable plug 27 to move, so that the movable plug 27 abuts against the limiting groove 29 at the top of the conveying pipe 28. The effective sealing is realized through the elasticity of the spring 26, the extrusion force makes the movable plug 27 deform, so that the movable plug 27 abuts against the inner wall of the connecting pipe 16, the effective sealing of the connection between the connecting pipe 16 and the conveying pipe 28 is realized, which is beneficial to improve the sealing performance and prevent the displacement gas from leaking, and is beneficial to ensure the safety production.

[0095] During the alternating gas injection, the gas is conveyed through the flow guide pipe 8 and the fixed pipe 9, and when the gas is conveyed through the connecting pipe 16 and the extension pipe 17, the position of the opening 171 is changed through the rotation of the connecting pipe 16 and the extension pipe 17, the conveying flow channel of different gases is switched, the rapid operation during the alternating gas injection is realized, which is beneficial to the continuous injection of the displacement gas during the shale oil exploitation, and realizes the continuous exploitation of the shale oil.

[0096] In the present application, unless specifically defined and limited otherwise, the "on" or "under" of a first feature to a second feature can include that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the "on", "above" and "under" of the first feature to the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the first feature is higher in horizontal height than the second feature. The "under", "below" and "under" of the first feature to the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the first feature is lower in horizontal height than the second feature.

[0097] In the description of the present application, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0098] In the present application, unless otherwise specifically defined and limited, the terms "connection", "fixing" and the like should be broadly understood, for example, "fixing" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection; can be directly connected, or indirectly connected through intermediate medium, can be internal connection of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0099] In addition, the description of "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implying the number of the indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically defined.

[0100] Although the embodiments of the present application have been shown and described, those skilled in the art can understand that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and purposes of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. A gas regulation device for alternating gas injection and displacement in shale oil, characterized in that, include: A fixed tube is provided with a sealing cap at one end, and at least two gas inlets for conveying different types of gases are provided on the side wall of the fixed tube. A rotating connecting pipe is provided with an opening on its circumference. The rotating connecting pipe is movably inserted into the fixed pipe and rotatably connected to the fixed pipe, so that the opening communicates with one of the air inlets. A delivery pipe, one end of which is movably inserted into the end of the rotating connecting pipe away from the fixed pipe, the rotating connecting pipe being rotatably connected to the delivery pipe, and the other end being detachably connected to an installation pipe for delivering the gas to the shale layer; a limit member is provided radially along the end of the delivery pipe inserted into the rotating connecting pipe. A movable plug is disposed around the periphery of the conveying pipe and is movably connected to the limiting member, and the periphery of the movable plug is in contact with the inner wall of the rotating connecting pipe. An elastic element is located inside the rotating connecting tube, with one end of the elastic element abutting against the side of the movable plug away from the limiting element, and the other end abutting against the inner wall of the rotating connecting tube. A connecting shaft is located inside the rotating connecting pipe and is rotatably connected to the rotating connecting pipe; An impeller is fixedly connected to one end of the connecting shaft and corresponds to the opening; The first bevel gear is disposed around the periphery of the other end of the connecting shaft and is fixedly connected to the connecting shaft; A rotating shaft is rotatably connected to the rotating connecting pipe, and the axis of the rotating shaft is parallel to the axis of the rotating connecting pipe; The second bevel gear is sleeved on the circumference of the rotating shaft and fixedly connected to the rotating shaft. The second bevel gear meshes with the first bevel gear. The stirring blades are arranged around the circumference of the rotating shaft and are fixedly connected to the rotating shaft.

2. The shale oil alternating gas injection displacement gas regulating device according to claim 1, characterized in that, The shale oil alternating gas injection displacement gas conditioning device also includes: The driving component is located on one side of the rotating connecting pipe; A transmission component is located between the driving component and the rotating connecting pipe. The driving component is connected to the rotating connecting pipe through the transmission component, causing the rotating connecting pipe to rotate around an axis.

3. The shale oil alternating gas injection displacement gas regulating device according to claim 2, characterized in that, The transmission component includes: A gear ring is arranged around the periphery of the rotating connecting pipe and is fixedly connected to the rotating connecting pipe; An adjusting gear is located on one side of the gear ring and meshes with the gear ring; the driving end of the driving member is connected to the adjusting gear.

4. The shale oil alternating gas injection displacement gas regulating device according to claim 1, characterized in that, The shale oil alternating gas injection displacement gas conditioning device also includes: A sealing ring is disposed around the periphery of the rotating connecting pipe and located between the rotating connecting pipe and the fixed pipe, and a through hole is provided at the position corresponding to the opening of the sealing ring.

5. The shale oil alternating gas injection displacement gas regulating device according to claim 1, characterized in that, The limiting member is provided with a limiting groove along the periphery of the conveying pipe, and the movable plug is provided with a limiting protrusion, the limiting groove being movably engaged within the limiting protrusion; or, the limiting member is provided with a limiting protrusion along the periphery of the conveying pipe, and the movable plug is provided with a limiting groove, the limiting protrusion being movably engaged within the limiting groove.

6. The shale oil alternating gas injection displacement gas regulating device according to claim 1, characterized in that, The shale oil alternating gas injection displacement gas conditioning device also includes: A connecting rod, one end of which is connected to the inner wall of the fixed tube, and the other end of which is provided with a mounting groove; The bearing is fitted into the mounting groove, the connecting rod is fitted into the bearing, and the impeller and the first bevel gear are located on both sides of the bearing.

7. The shale oil alternating gas injection displacement gas regulating device according to claim 1, characterized in that, The shale oil alternating gas injection displacement gas conditioning device also includes: A sleeve shaft is located inside the fixed tube and installed on the sealing cover, and one end of the rotating shaft is movably sleeved inside the sleeve shaft; A fixing plate is located inside the fixing tube and is fixedly connected to the inner wall of the fixing tube. The fixing plate has a transition hole, and the rotating shaft is movably sleeved in the transition hole. The fixing plate is clamped between the second bevel gear and the stirring blade.

8. A gas delivery device for alternating gas injection and displacement in shale oil, characterized in that, include: The shale oil alternating gas injection displacement gas regulation device as described in any one of claims 1 to 7; At least two gas storage tanks are connected to the gas inlet, and the number of gas storage tanks is equal to the number of gas inlets; A stirring shaft is rotatably mounted inside the gas storage tank; A stirring rod is located around the stirring shaft and is fixedly connected to the stirring shaft.

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