Motion-free gas production string drainage, sand extraction and blockage removal device and usage method

Abstract

The present invention relates to the field of natural gas well mining technology, and in particular to a device for draining, pumping, and unblocking a gas production pipe without moving, and a method for using the device. The technical solution is as follows: the lower water inlet end of the nozzle is connected to the power water inlet provided on the outer wall of the pump body, the lower end of the nozzle is provided with a central tube, the upper water outlet end of the nozzle is connected to the formation fluid inlet chamber, an expansion rubber cylinder is provided on the lower side of the pump body, and an upper pressure transmission hole is provided between the expansion rubber cylinder and the central tube; a slip rubber cylinder is provided on the lower side of the pump body, a slip sheet is provided on the outer side of the slip rubber cylinder, a lower pressure transmission hole is provided between the slip rubber cylinder and the central tube, and a formation fluid suction port is provided at the lower end of the pump body; a flushing pipe is provided at the bottom of the central tube, and a sand suspension nozzle is provided at the bottom of the flushing pipe. The beneficial effect is that, without moving the gas production pipe, the present invention can drive the device of the present invention to pump sand by inserting a continuous oil pipe into the inner cavity of the gas production pipe, thereby meeting the sand pumping and unblocking needs specifically for natural gas wells and avoiding well control safety and environmental protection issues of natural gas wells.

Description

Technical Field

[0001] The present invention relates to the technical field of natural gas well mining, and in particular to a motion-free gas production pipe column water drainage, sand pumping and blockage removal device and a use method thereof. Background Art

[0002] As high-pressure, high-sulfur natural gas wells are mined over long periods of time, formation pressure gradually decreases, leading to a continuous decrease in gas production. This intensifies the accumulation of water and sand at the bottom of the natural gas well, as well as the return of fracturing sand, which impacts and restricts gas production. In severe cases, sand blockage can lead to reduced production and even forced well closure. Existing sand bailing and sand clearing devices for gas wells require the well to be killed and the gas string removed before they can be used. High-pressure, high-toxic gas wells, due to safety and economic constraints, cannot frequently be activated for production. Existing technologies and equipment cannot achieve sand clearing and blockage removal without moving the gas string. Even after moving the gas string, the process is complex, inefficient, difficult to completely clear, expensive, and carries significant safety and environmental risks and potential hazards.

[0003] Existing gas well drainage technologies, such as foam drainage, plunger drainage, and gas lift, are not yet sufficient for sand extraction. Using coiled tubing to circulate gas and water through the wellbore can cause the backflow of construction fluid into the reservoir, seriously halting gas production, and can easily lead to sand plugging of the construction string. The latest double-layer coiled tubing driven by Venturi tube drainage and sand extraction devices within the gas production string also suffers from the limited inner diameter of the tubing, resulting in a narrow fluid flow channel, excessive fluid friction, low lift head, and susceptibility to sand plugging. This leads to high energy consumption, low drainage and sand extraction efficiency, and severe wear of the coiled tubing by the sand and fluid, resulting in high construction risks and costs.

[0004] The invention patent "A Two-stage Jet Negative Pressure Sand Pumping String for Oil and Gas Wells" applied by our company on June 12, 2024 is a technology for pumping sand inside the casing of an oil well. It is mainly suitable for oil wells and coalbed methane horizontal wells without production strings in the well. It cannot be operated in the inner cavity of a gas production string with a smaller inner diameter, nor can it be operated in a step-by-step manner. In addition, due to the restrictions of natural gas well control safety and environmental protection, it cannot be applied to the sand pumping needs of high-pressure and high-hydrogen sulfide content natural gas wells. Summary of the Invention

[0005] The purpose of the present invention is to address the above-mentioned defects of the prior art and provide a device and method for using a motion-free gas production pipe to drain water, pump out sand and unblock. Without moving the gas production pipe, a continuous oil pipe is inserted into the inner cavity of the gas production pipe to drive the device of the present invention to pump out sand, thereby meeting the needs of sand pumping and unblocking specifically for natural gas wells, avoiding the occurrence of well control safety and environmental protection problems of natural gas wells; and it can realize step-by-step operation, effectively realizing the sand pumping work of the natural gas well.

[0006] The present invention mentions a motionless gas production pipe drainage, sand extraction and blockage removal device, whose technical solution is: it includes a pump body, a diffuser, a throat and a nozzle, the upper inner cavity of the pump body is provided with a diffuser, the lower part of the diffuser is connected to the throat, and the lower part of the throat is provided with a nozzle, wherein it also includes a power water inlet, a center pipe, a leather cup, an upload pressure hole, an expansion rubber cylinder, a slip rubber cylinder, a lower pressure transmission hole, a formation fluid suction port, a suspended sand nozzle, and a slip piece. The lower water inlet end of the nozzle is connected to the power water inlet provided on the outer wall of the pump body, the lower end of the nozzle is provided with a center pipe, the upper water outlet end of the nozzle is connected with the formation fluid inlet cavity, an expansion rubber cylinder is provided on the lower side of the pump body, and an upload pressure hole is provided between the expansion rubber cylinder and the center pipe; a slip rubber cylinder is provided on the lower side of the pump body, a slip piece is provided on the outer side of the slip rubber cylinder, a lower pressure transmission hole is provided between the slip rubber cylinder and the center pipe, and a formation fluid suction port is provided at the lower end of the pump body; a flushing pipe is provided at the bottom of the center pipe, and a suspended sand nozzle is provided at the bottom of the flushing pipe.

[0007] Preferably, the above-mentioned central tube includes a central tube body, an upper liquid cavity, a necked liquid passage, a lower liquid cavity, a first connecting hole, a second connecting hole, and a central tube lower outlet. The middle and lower parts of the central tube body are provided with a necked liquid passage, the upper part forms an upper liquid cavity, the lower part forms a lower liquid cavity, and the tube wall of the middle and upper part of the central tube body is provided with a first connecting hole and a second connecting hole, and the lower end part of the central tube body is provided with a central tube lower outlet.

[0008] Preferably, the above-mentioned flushing pipe adopts a rotating flushing pipe, which is connected to the inner wall of the central pipe through one or more bearings, one or more rotating pulse nozzles are provided on the lower side of the rotating flushing pipe, and a suspended sand nozzle is connected to the bottom of the rotating flushing pipe.

[0009] Preferably, the above-mentioned rotary punching tube includes a rotating guide tube, spiral blades, a bearing sleeve, and a spiral blade mounting sleeve. A spiral blade mounting sleeve is provided on the outer wall of the rotating guide tube, spiral blades are distributed on the outside of the spiral blade mounting sleeve, and a bearing sleeve is provided on the lower side of the spiral blade mounting sleeve for connecting with the bearing; a plurality of nozzle mounting screw holes are provided on the lower side of the rotating guide tube for installing a rotary pulse nozzle.

[0010] Preferably, a leather cup is provided on the lower middle side of the pump body and is located on the upper side of the expansion rubber cylinder.

[0011] Preferably, the upper pressure transmission hole is connected to the first connection hole through a first thin tube, and the lower pressure transmission hole is connected to the second connection hole through a second thin tube.

[0012] Preferably, the above-mentioned rotary pulse nozzle includes a pulse nozzle body, an oscillation chamber, an oscillation liquid outlet, a pulse amplification chamber, a pulse liquid outlet, and a liquid inlet. The inner cavity of the pulse nozzle body is provided with an oscillation chamber and a pulse amplification chamber. The oscillation chamber and the pulse amplification chamber are connected through the oscillation liquid outlet. A liquid inlet is provided on the outside of the oscillation chamber for connecting with the inner cavity of the rotary flushing tube; a pulse liquid outlet is provided at the outer end of the pulse amplification chamber, and an outer wall of the pulse nozzle body is provided with an external thread.

[0013] Preferably, the above-mentioned flushing pipe adopts a telescopic flushing pipe, and the upper end of the telescopic flushing pipe is provided with a raised limiting step, which cooperates with the limiting ring installed at the lower end of the central tube to enable the telescopic flushing pipe to move up and down in the lower liquid cavity, and the bottom of the telescopic flushing pipe is connected to the suspended sand nozzle.

[0014] Preferably, the above-mentioned sand-suspending nozzle includes a sand-suspending nozzle body, an inner spiral groove, and a lower outlet of the sand-suspending nozzle. The inner cavity of the sand-suspending nozzle body is provided with an inner spiral groove, the lower end of the inner spiral groove is connected to the lower outlet of the sand-suspending nozzle, and the outer wall of the sand-suspending nozzle body is provided with an external thread, which is connected and cooperated with the internal thread at the bottom of the flushing pipe.

[0015] The method for using the non-movable gas production column drainage and sand removal device mentioned in the present invention includes the following steps:

[0016] 1. Use the coiled tubing to send the motion-free gas production string water drainage and sand removal device into the sand-blocked section of the gas production string, and install the wellhead device;

[0017] Second, power fluid is injected into the production pipe string at the wellhead device on the ground. The power fluid reaches the power water inlet along the annular space between the production pipe string and the coiled tubing. The power fluid is divided into two paths. One path accelerates the jet along the nozzle, while the other part of the power fluid moves downward along the central pipe to expand the expansion cylinder and drive the lower rotary flushing pipe to rotate. At the same time, the power fluid is ejected along the rotating pulse nozzle and is also accelerated downward along the sand-suspending nozzle to impact the suspended sand. Under the action of the sand-suspending nozzle and the rotating pulse nozzle, the sand is stirred and mixed with the formation fluid to form a formation sand-containing fluid. Then, the high-speed liquid flow ejected from the upper nozzle is drawn and the combined liquid formed after absorbing the formation sand-containing fluid from the formation fluid suction inlet enters the throat pipe for mixing and energy conversion, and then passes through the diffuser to decelerate and increase the pressure, and then moves upward along the inner cavity of the coiled tubing to the ground. As the sand liquid at the bottom of the well is discharged, the injection of power fluid is stopped when the formation sand-containing fluid extracted from the ground is almost free of sand.

[0018] 3. After stopping the injection of power fluid, the expansion rubber cylinder and slip rubber cylinder will shrink, and then the coiled tubing will be slowly lowered so that the lower end of the rotary flushing pipe will reach the new sand surface. The above operation will be repeated, realizing a step-by-step cycle of repeated operations until all the accumulated sand in the gas production string and at the bottom of the natural gas well is pumped out of the ground from top to bottom, and the injection of power fluid will be stopped;

[0019] 4. Then, the driving gas is injected on the ground to reversely circulate the water in the gas production string out of the ground. Finally, the coiled tubing is lifted up to remove the motionless gas production string water drainage and sand removal device to restore normal gas production in the natural gas well.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] 1. Under the condition of no need to move the gas production string, the present invention lowers a single layer of continuous oil tubing into the well to drag the no need to move the gas production string water drainage, sand extraction and blockage removal device, and step-by-step lowering of the string to suck the sand and water at the bottom of the well out of the ground. The construction is convenient, the water drainage and sand suction efficiency is high, the economic performance is good, and the construction risks such as sand stuck in the construction string are avoided. The present invention effectively improves the gas production time rate of the natural gas well, and can be constructed intermittently according to the water and sand production conditions of the well, or after the water and sand accumulated at the bottom of the well are cleared, natural gas can be reinjected to drain and clear the sand for production. It has strong adaptability to the well conditions of the natural gas well and can better meet the drainage and production needs of different production parameters and gas-water-sand production ratios in multiple production stages. It has the dual effects of sand removal and near-well blockage removal, and thus has an excellent production increase effect.

[0022] 2. The present invention uses a leather cup and an expansion rubber sleeve driven by a power fluid to seal the annular space of the oil casing, construct a sand discharge channel, and realize reliable jet pumping and sand absorption. The slip rubber sleeve and slip sheet can be anchored on the inner wall of the casing, and a step-by-step cycle operation can be realized. Each step can realize sand extraction work for this section of the wellbore, and then the next section of the wellbore can be pumped out. It has the advantages of novel structure, easy unsealing, reliable sealing, not easy to get the pipe string stuck, high water and sand absorption efficiency, protection of the reservoir from flooding, convenient operation, and low cost.

[0023] 3. In summary, the present invention runs a continuous oil pipe into the inner cavity of the gas production string to drive the device of the present invention to pump sand without moving the gas production string, thereby meeting the needs of sand pumping and unblocking for natural gas wells and avoiding well control safety and environmental protection problems of natural gas wells. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic structural diagram of embodiment 1 of the present invention;

[0025] Figure 2 yes Figure 1 AA cross-sectional structural diagram in FIG;

[0026] Figure 3 It is a structural diagram of the central tube;

[0027] Figure 4 It is a structural diagram of a rotary punch;

[0028] Figure 5 It is a structural diagram of a rotary pulse nozzle;

[0029] Figure 6 It is a structural diagram of the suspended sand nozzle;

[0030] Figure 7 is a schematic structural diagram of embodiment 2 of the present invention;

[0031] Figure 8 yes Figure 7 BB cross-sectional structure diagram in;

[0032] Figure 9 This is a schematic diagram of the underground well during the construction of the present invention;

[0033] In the figure above: coiled tubing 1, pump body 2, diffuser 3, throat 4, nozzle 5, power water inlet 6, center pipe 7, leather cup 8, upper pressure hole 9, expansion rubber cylinder 10, slip rubber cylinder 11, lower pressure hole 12, formation fluid suction inlet 13, rotary flushing pipe 14, bearing 15, rotary pulse nozzle 16, sand suspension nozzle 17, slip 18, first capillary 19, second capillary 20, telescopic flushing pipe 21, limit ring 22, casing 23, gas production string 24, center pipe body 7.1, upper fluid chamber 7.2, necked fluid passage 7.3, lower fluid passage Liquid chamber 7.4, first connecting hole 7.5, second connecting hole 7.6, center tube lower outlet 7.7, rotating guide tube 14.1, spiral blade 14.2, bearing sleeve 14.3, spiral blade mounting sleeve 14.4, nozzle mounting screw hole 14.5, pulse nozzle body 16.1, oscillation chamber 16.2, oscillation liquid outlet 16.3, pulse amplification chamber 16.4, pulse liquid outlet 16.5, liquid inlet 16.6, sand suspension nozzle body 17.1, inner spiral groove 17.2, sand suspension nozzle lower outlet 17.3, limit step 21.1. DETAILED DESCRIPTION

[0034] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0035] Example 1, with reference to Figures 1-6The present invention mentions a non-motion gas production column drainage and sand removal device, including a pump body 2, a diffusion pipe 3, a throat pipe 4 and a nozzle 5. The upper inner cavity of the pump body 2 is provided with a diffusion pipe 3, the lower part of the diffusion pipe 3 is connected to the throat pipe 4, and the lower part of the throat pipe 4 is provided with a nozzle 5, which also includes a power water inlet 6, a center pipe 7, a leather cup 8, an upper pressure hole 9, an expansion rubber cylinder 10, a slip rubber cylinder 11, a lower pressure hole 12, a formation fluid suction port 13, a suspended sand nozzle 17, and a slip piece 18. The lower water inlet end of the nozzle 5 is connected to the outer wall of the pump body 2. The power water inlet 6 is provided, and a central pipe 7 is provided at the lower end of the nozzle 5. The upper water outlet end of the nozzle 5 is connected with the formation fluid inlet cavity. An expansion rubber cylinder 10 is provided on the lower side of the pump body 2, and an upper pressure transmission hole 9 is provided between the expansion rubber cylinder 10 and the central pipe 7; a slip rubber cylinder 11 is provided on the lower side of the pump body 2, and a slip piece 18 is provided on the outside of the slip rubber cylinder 11. A lower pressure transmission hole 12 is provided between the slip rubber cylinder 11 and the central pipe 7, and a formation fluid suction port 13 is provided at the lower end of the pump body 2; a flushing pipe is provided at the bottom of the central pipe 7, and a sand suspension nozzle 17 is provided at the bottom of the flushing pipe.

[0036] Reference Figure 3 The central tube 7 mentioned in the present invention includes a central tube body 7.1, an upper liquid chamber 7.2, a necked liquid passage 7.3, a lower liquid chamber 7.4, a first connecting hole 7.5, a second connecting hole 7.6, and a central tube lower outlet 7.7. The central tube body 7.1 is provided with a necked liquid passage 7.3 in the middle and lower part, an upper liquid chamber 7.2 is formed in the upper part, and a lower liquid chamber 7.4 is formed in the lower part. The first connecting hole 7.5 and the second connecting hole 7.6 are provided on the tube wall of the middle and upper part of the central tube body 7.1, and a central tube lower outlet 7.7 is provided at the lower end of the central tube body 7.1.

[0037] Among them, the above-mentioned flushing pipe adopts a rotating flushing pipe 14, which is connected to the inner wall of the central pipe 7 through one or more bearings 15. One or more rotating pulse nozzles 16 are provided on the lower side of the rotating flushing pipe 14, and a suspended sand nozzle 17 is connected to the bottom of the rotating flushing pipe 14.

[0038] Reference Figure 4 The rotary punching pipe 14 mentioned in the present invention includes a rotary guide tube 14.1, a spiral blade 14.2, a bearing sleeve 14.3, and a spiral blade mounting sleeve 14.4. A spiral blade mounting sleeve 14.4 is provided on the outer wall of the rotary guide tube 14.1, and spiral blades 14.2 are distributed on the outside of the spiral blade mounting sleeve 14.4. A bearing sleeve 14.3 is provided on the lower side of the spiral blade mounting sleeve 14.4 for matching and connecting with the bearing 15; a plurality of nozzle mounting screw holes 14.5 are provided on the lower side of the rotary guide tube 14.1 for installing the rotary pulse nozzle 16.

[0039] A leather cup 8 is provided on the lower middle side of the pump body 2 and is located on the upper side of the expansion rubber cylinder 10 .

[0040] The upper pressure-transmitting hole 9 is connected to the first connecting hole 7.5 via a first thin tube 19, and the lower pressure-transmitting hole 12 is connected to the second connecting hole 7.6 via a second thin tube 20.

[0041] Reference Figure 5 The rotary pulse nozzle 16 mentioned in the present invention includes a pulse nozzle body 16.1, an oscillation chamber 16.2, an oscillation liquid outlet 16.3, a pulse amplification chamber 16.4, a pulse liquid outlet 16.5, and a liquid inlet 16.6. The inner cavity of the pulse nozzle body 16.1 is provided with an oscillation chamber 16.2 and a pulse amplification chamber 16.4. The oscillation chamber 16.2 and the pulse amplification chamber 16.4 are connected through the oscillation liquid outlet 16.3. A liquid inlet 16.6 is provided on the outside of the oscillation chamber 16.2 for communicating with the inner cavity of the rotary flushing tube 14; a pulse liquid outlet 16.5 is provided at the outer end of the pulse amplification chamber 16.4, and the outer wall of the pulse nozzle body 16.1 is provided with an external thread.

[0042] Reference Figure 6 The sand-suspending nozzle 17 mentioned in the present invention includes a sand-suspending nozzle body 17.1, an inner spiral groove 17.2, and a lower outlet 17.3 of the sand-suspending nozzle. The inner cavity of the sand-suspending nozzle body 17.1 is provided with an inner spiral groove 17.2, and the lower end of the inner spiral groove 17.2 is connected to the lower outlet 17.3 of the sand-suspending nozzle. The outer wall of the sand-suspending nozzle body 17.1 is provided with an external thread, which is connected to the internal thread at the bottom of the flushing pipe.

[0043] In addition, a plurality of serrated slips 18 are vulcanized on the outer wall of the slip cartridge 10 to achieve the effect of anchoring on the inner wall of the casing 23 and also to suppress the creep of the pipe string.

[0044] The method for using the non-movable gas production column drainage and sand removal device mentioned in the present invention includes the following steps: Figure 9 ,

[0045] 1. Deliver the motion-free gas production string water drainage and sand removal device into the sand-blocked section of the gas production string 24 through the coiled tubing 1, and install the wellhead device.

[0046] Second, power fluid is injected into the production string 24 at the surface wellhead assembly. The power fluid flows along the annular space between the production string 24 and the coiled tubing 1 to the power water inlet 6. The power fluid is then divided into two paths. One path accelerates the jet along the nozzle 5, while the other path descends along the central pipe 7 to expand the expansion rubber sleeve 10 and drive the lower rotary flushing pipe 14 to rotate. Simultaneously, the power fluid is ejected along the rotary pulse nozzle 16 and is also accelerated downward along the sand-suspending nozzle 17 to suspend the settled sand. Under the action of the sand-suspending nozzle 17 and the rotary pulse nozzle 16, the settled sand is stirred and mixed with the formation fluid to form a confluent sand-containing fluid. Then, the high-speed fluid ejected from the upper nozzle 5 draws and absorbs the formation sand-containing fluid from the formation fluid suction port 13, forming a confluent fluid that enters the throat pipe 4 for mixing and energy conversion. After being decelerated and pressurized by the diffuser 3, it ascends along the inner cavity of the coiled tubing 1 to the surface. As the sand-containing fluid at the bottom of the well is discharged, the power fluid injection is stopped when the formation sand-containing fluid extracted from the surface is almost free of sand.

[0047] 3. After stopping the injection of the power fluid, the expansion rubber cylinder 10 and the slip rubber cylinder 11 will shrink, and then the coiled tubing 1 will be slowly lowered so that the lower end of the rotary flushing pipe 14 will reach the new sand surface. The above operation will be repeated, realizing a step-by-step cycle of repeated operations until all the sand accumulated in the gas production string 24 and at the bottom of the natural gas well is pumped out of the ground from top to bottom, and the injection of the power fluid is stopped;

[0048] Fourth, the driving gas is then injected on the ground to reversely circulate the water in the gas production string 24 out of the ground. Finally, the coiled tubing 1 is lifted up to remove the non-movable gas production string water drainage and sand removal device to resume normal gas production in the natural gas well.

[0049] Example 2, the present invention mentions a non-motion gas production column drainage and sand removal device, its technical solution is: including a pump body 2, a diffuser 3, a throat pipe 4 and a nozzle 5, the upper inner cavity of the pump body 2 is provided with a diffuser 3, the lower part of the diffuser 3 is connected to the throat pipe 4, the lower part of the throat pipe 4 is provided with a nozzle 5, which also includes a power water inlet 6, a center pipe 7, a leather cup 8, an upper pressure hole 9, an expansion rubber cylinder 10, a slip rubber cylinder 11, a lower pressure hole 12, a formation fluid suction port 13, a suspended sand nozzle 17, a slip piece 18, and a pump is connected to the water inlet end at the lower part of the nozzle 5 The outer wall of the body 2 is provided with a power water inlet 6, the lower end of the nozzle 5 is provided with a central pipe 7, the upper water outlet end of the nozzle 5 is connected with the formation fluid inlet cavity, an expansion rubber cylinder 10 is provided on the lower side of the pump body 2, and an upper pressure transmission hole 9 is provided between the expansion rubber cylinder 10 and the central pipe 7; a slip rubber cylinder 11 is provided on the lower side of the pump body 2, a slip piece 18 is provided on the outside of the slip rubber cylinder 11, a lower pressure transmission hole 12 is provided between the slip rubber cylinder 11 and the central pipe 7, and a formation fluid suction port 13 is provided at the lower end of the pump body 2; a flushing pipe is provided at the bottom of the central pipe 7, and a sand suspension nozzle 17 is provided at the bottom of the flushing pipe.

[0050] The difference from Example 1 is:

[0051] Reference Figure 7 and Figure 8 The flushing pipe mentioned in this embodiment adopts a telescopic flushing pipe 21. The upper end of the telescopic flushing pipe 21 is provided with a raised limit step 21.1. The raised limit step 21.1 cooperates with the limit ring 22 installed at the lower end of the central tube 7, so that the telescopic flushing pipe 21 moves up and down in the lower liquid chamber 7.4. The bottom of the telescopic flushing pipe 21 is connected to the suspended sand nozzle 17.

[0052] The method for using the non-movable gas production column water drainage and sand removal device mentioned in this embodiment includes the following steps:

[0053] 1. Deliver the motion-free gas production string water drainage and sand removal device into the sand-blocked section of the gas production string 24 through the coiled tubing 1, and install the wellhead device.

[0054] Second, at the surface wellhead, power fluid is injected into the gas production string 24. The power fluid flows along the annular space between the gas production string 24 and the coiled tubing 1 to the power water inlet 6. The power fluid is divided into two paths. One path accelerates the jet along the nozzle 5, while the other path descends along the central pipe 7 to expand the expansion rubber cylinder 10 and drive the lower telescopic flushing pipe 21 downward. The power fluid is accelerated downward along the sand-suspending nozzle 17 to impact the suspended sand. Under the action of the sand-suspending nozzle 17, the sand is stirred and mixed with the formation fluid to form a formation sand-containing fluid. Then, the high-speed liquid flow ejected from the upper nozzle 5 is drawn and absorbed from the formation sand-containing fluid suction port 13. The resulting combined fluid enters the throat pipe 4 for mixing and energy conversion. After being decelerated and pressurized by the diffuser 3, it ascends along the inner cavity of the coiled tubing 1 to the surface. As the sand-containing fluid at the bottom of the well is discharged, the injection of power fluid is stopped when the formation sand-containing fluid extracted from the surface is almost free of sand.

[0055] 3. After stopping the injection of the power fluid, the expansion rubber cylinder 10 and the slip rubber cylinder 11 will shrink, and then the coiled tubing 1 will be slowly lowered so that the lower end of the rotary flushing pipe 14 will reach the new sand surface. The above operation will be repeated, realizing a step-by-step cycle of repeated operations until all the sand accumulated in the gas production string 24 and at the bottom of the natural gas well is pumped out of the ground from top to bottom, and the injection of the power fluid is stopped;

[0056] Fourth, the driving gas is then injected on the ground to reversely circulate the water in the gas production string 24 out of the ground. Finally, the coiled tubing 1 is lifted up to remove the non-movable gas production string water drainage and sand removal device to resume normal gas production in the natural gas well.

[0057] The above descriptions are merely some preferred embodiments of the present invention. Anyone skilled in the art may be able to modify the above-described technical solutions or convert them into equivalent technical solutions. Therefore, any corresponding simple modifications or equivalent transformations based on the technical solutions of the present invention fall within the scope of protection claimed by the present invention.

Claims

1. A device for draining and removing sand from a motionless gas production column, comprising a pump body (2), a diffuser (3), a throat pipe (4) and a nozzle (5), wherein the upper inner cavity of the pump body (2) is provided with a diffuser (3), the lower portion of the diffuser (3) is connected to the throat pipe (4), and the lower portion of the throat pipe (4) is provided with a nozzle (5), wherein: The invention also includes a power water inlet (6), a central tube (7), a leather cup (8), an upper pressure transmission hole (9), an expansion rubber cylinder (10), a slip rubber cylinder (11), a lower pressure transmission hole (12), a formation fluid suction port (13), a suspended sand nozzle (17), and a slip sheet (18). The power water inlet (6) provided on the outer wall of the pump body (2) is connected to the lower water inlet end of the nozzle (5), a central tube (7) is provided at the lower end of the nozzle (5), and the upper water outlet end of the nozzle (5) is communicated with the formation fluid inlet cavity. 2) is provided with an expansion rubber cylinder (10) on the lower side, and an upper pressure transmission hole (9) is provided between the expansion rubber cylinder (10) and the central tube (7); a slip rubber cylinder (11) is provided on the lower side of the pump body (2), a slip sheet (18) is provided on the outer side of the slip rubber cylinder (11), a lower pressure transmission hole (12) is provided between the slip rubber cylinder (11) and the central tube (7), and a formation fluid suction port (13) is provided at the lower end of the pump body (2); a flushing pipe is provided at the bottom of the central tube (7), and a sand suspension nozzle (17) is provided at the bottom of the flushing pipe.

2. The device for draining, pumping out sand and unblocking gas pipes according to claim 1 is characterized by: The central tube (7) comprises a central tube body (7.1), an upper liquid cavity (7.2), a necked liquid passage (7.3), a lower liquid cavity (7.4), a first connecting hole (7.5), a second connecting hole (7.6), and a central tube lower outlet (7.7). The central tube body (7.1) is provided with a necked liquid passage (7.3) at its lower middle portion, an upper liquid cavity (7.2) is formed at its upper portion, and a lower liquid cavity (7.4) is formed at its lower portion. The central tube body (7.1) is provided with a first connecting hole (7.5) and a second connecting hole (7.6) on its upper middle portion of its wall, and a central tube lower outlet (7.7) is provided at its lower end portion.

3. The device for draining, pumping out sand and unblocking gas pipes according to claim 2 is characterized by: The flushing pipe adopts a rotating flushing pipe (14), which is connected to the inner wall of the central pipe (7) through one or more bearings (15), one or more rotating pulse nozzles (16) are provided on the lower side of the rotating flushing pipe (14), and a suspended sand nozzle (17) is connected to the bottom of the rotating flushing pipe (14).

4. The device for draining, pumping sand and unblocking a motion-free gas production column according to claim 3 is characterized by: The rotary punching tube (14) comprises a rotary guide tube (14.1), a spiral blade (14.2), a bearing sleeve (14.3), and a spiral blade mounting sleeve (14.4). A spiral blade mounting sleeve (14.4) is provided on the outer wall of the rotary guide tube (14.1), spiral blades (14.2) are distributed on the outer side of the spiral blade mounting sleeve (14.4), and a bearing sleeve (14.3) is provided on the lower side of the spiral blade mounting sleeve (14.4) for mating with a bearing (15); a plurality of nozzle mounting screw holes (14.5) are provided on the lower side of the rotary guide tube (14.1) for mounting a rotary pulse nozzle (16).

5. The device for draining, pumping out sand and unblocking gas pipes according to claim 4 is characterized by: A leather cup (8) is provided on the middle and lower side of the pump body (2) and is located on the upper side of the expansion rubber cylinder (10).

6. The device for draining, pumping sand and unblocking a motion-free gas production column according to claim 5 is characterized by: The upper pressure transmission hole (9) is connected to the first connection hole (7.5) via a first thin tube (19), and the lower pressure transmission hole (12) is connected to the second connection hole (7.6) via a second thin tube (20).

7. The device for draining, sand extraction and unblocking a motion-free gas production column according to claim 6 is characterized by: The rotary pulse nozzle (16) comprises a pulse nozzle body (16.1), an oscillation chamber (16.2), an oscillation liquid outlet (16.3), a pulse amplification chamber (16.4), a pulse liquid outlet (16.5), and a liquid inlet (16.6). The inner cavity of the pulse nozzle body (16.1) is provided with an oscillation chamber (16.2) and a pulse amplification chamber (16.4). The oscillation chamber (16.2) and the pulse amplification chamber (16.4) are connected via the oscillation liquid outlet (16.3). A liquid inlet (16.6) is provided on the outer side of the oscillation chamber (16.2) for communicating with the inner cavity of the rotary flushing tube (14); a pulse liquid outlet (16.5) is provided at the outer end of the pulse amplification chamber (16.4), and an outer wall of the pulse nozzle body (16.1) is provided with an external thread.

8. The device for draining, pumping sand and unblocking a motion-free gas production column according to claim 2 is characterized by: The flushing pipe adopts a telescopic flushing pipe (21), the upper end of which is provided with a raised limiting step (21.1), which cooperates with a limiting ring (22) installed at the lower end of the central pipe (7) to enable the telescopic flushing pipe (21) to move up and down in the lower liquid chamber (7.4), and the bottom of the telescopic flushing pipe (21) is connected to the suspended sand nozzle (17).

9. The motion-free gas production column drainage, sand extraction and blockage removal device according to claim 7 or 8, characterized in that: The sand-suspending nozzle (17) comprises a sand-suspending nozzle body (17.1), an inner spiral groove (17.2), and a lower outlet (17.3) of the sand-suspending nozzle body. The inner cavity of the sand-suspending nozzle body (17.1) is provided with an inner spiral groove (17.2), the lower end of the inner spiral groove (17.2) is communicated with the lower outlet (17.3) of the sand-suspending nozzle body, and the outer wall of the sand-suspending nozzle body (17.1) is provided with an external thread, which is connected and matched with the internal thread at the bottom of the flushing pipe.

10. The method for using the motion-free gas production column drainage, sand extraction and blockage removal device according to claim 7, characterized in that: The following processes are included:

1. Send the motion-free gas production string water drainage and sand removal device into the sand-blocked section of the gas production string (24) through the coiled tubing (1), and install the wellhead device; Second, at the wellhead device on the ground, power fluid is injected into the gas production string (24). The power fluid flows along the annular space between the gas production string (24) and the continuous oil pipe (1) to reach the power water inlet (6). The power fluid is divided into two paths. One path accelerates the jet along the nozzle (5), while the other part of the power fluid goes down along the center pipe (7) to expand the expansion rubber cylinder (10) and drives the lower rotating flushing pipe (14) to rotate. At the same time, the power fluid is ejected along the rotating pulse nozzle (16). The power fluid also accelerates downward along the suspended sand nozzle (17) to impact the suspended sand. Sand settling, under the action of the sand-suspending nozzle (17) and the rotating pulse nozzle (16), the sand settling is stirred and mixed with the formation fluid to form a formation sand-containing fluid; then, the high-speed liquid flow ejected by the upper nozzle (5) is drawn and absorbed from the formation sand-containing fluid from the formation fluid suction port (13) to form a confluent fluid that enters the throat pipe (4) for mixing and energy conversion, and then passes through the diffusion pipe (3) to decelerate and increase the pressure before ascending along the inner cavity of the continuous oil pipe (1) to the ground. As the sand fluid at the bottom of the well is discharged, when the formation sand-containing fluid extracted from the ground is close to being free of sand, the injection of the power fluid is stopped; 3. After the injection of the power fluid is stopped, the expansion rubber cylinder (10) and the slip rubber cylinder (11) will shrink, and then the coiled tubing (1) will be slowly lowered so that the lower end of the rotary flushing pipe (14) will reach the new sand surface, and then the above operation will be repeated, realizing a step-by-step cycle of repeated operations until all the sand accumulated in the gas production string (24) and at the bottom of the natural gas well is pumped out of the ground from top to bottom, and the injection of the power fluid is stopped; Fourth, the driving gas is then injected on the ground to reversely circulate the water in the gas production string (24) out of the ground. Finally, the coiled tubing (1) is lifted up to remove the non-movable gas production string water drainage and sand removal device to resume normal gas production in the natural gas well.

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