A multi-stage pneumatic jet relay drainage gas recovery device and drainage and recovery method

Abstract

The present application relates to the technical field of gas well drainage, in particular to a multi-stage pneumatic jetting relay drainage gas recovery device and a drainage method. The technical scheme is: connecting a pressure control switch jetting pump with a tubing and lowering the tubing into a downhole casing, connecting a pneumatic jetting pump with the pressure control switch jetting pump through a connecting pipe at the lower end of the pressure control switch jetting pump, providing a plurality of power gas flow limiting ring holes on the outer wall of the middle and lower part of the pneumatic jetting pump, providing a pressure boosting diffusion cavity, a mixing energy conversion cavity, a gas jetting acceleration cavity and a power gas temporary storage cavity from top to bottom inside, and installing a center pipe in the center of the gas jetting acceleration cavity and the power gas temporary storage cavity. The beneficial effects are: the present application uses gas as a jetting power medium to drive the pressure control switch jetting pump and the pneumatic jetting pump to drain liquid, organically combines gas relay jetting, gas lifting and gas expansion energy, and lifts the downhole accumulated water to the ground in the form of dispersed misty gas-water two-phase fluid, having the advantages of good reliability, high lifting head, good gas-water atomization and water slip prevention effect.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of gas well drainage, in particular to a multi-stage pneumatic jet relay drainage gas recovery device and a drainage method. BACKGROUND

[0002] With the decrease of formation energy and gas production and the increase of water accumulation at the bottom of the well in the production process of the gas well, the traditional foam drainage gas recovery technology, which is to generate foam by injecting surfactant into the gas well to "take" the water accumulation at the bottom of the well to solve the liquid accumulation problem, has the problems of insufficient lift and easy reservoir pollution. In addition, methods such as plunger drainage and submersible electric pump are used, which have the problems of limited lift, low efficiency, high failure rate, high cost, and low reliable performance of low-pressure deep well drainage. Another technology is to use gas-driven gas lift valve drainage technology, which has the characteristics of simple ground system, low investment and low energy consumption. However, due to the large difference in physical properties between the driving medium and the pumped medium in the gas-driven gas lift valve, the lifting lift is lower than that of the water power jet pump. With the upward movement of gas-water two-phase flow, the gas-water two-phase flow state changes in the long-distance upward process due to the density difference, and the gas-water mixture uniformity decreases due to the coalescence of mist droplets, which easily leads to water-gas slip-off, resulting in low gas-water carrying efficiency. The application of gas lift valve drainage in gas wells is limited by the lifting lift and efficiency, especially for gas wells that need to lift more than 3000 meters, the lifting efficiency is low, and the water cannot be effectively lifted to the ground.

[0003] Therefore, it is necessary to design a multi-stage pneumatic jet relay drainage gas recovery device and a drainage method to solve the above problems. SUMMARY

[0004] The purpose of the present application is to solve the above-mentioned defects in the prior art, provide a multi-stage pneumatic jet relay drainage gas recovery device and a drainage method, by designing a special pressure-controlled switch jet pump and a pneumatic jet pump, effectively solving the problem of low efficiency caused by water-gas slip-off of the gas lift valve, and organically combining gas relay jetting, gas lifting and gas expansion energy to lift the water accumulation at the bottom of the well to the ground as dispersed mist gas-water two-phase fluid. It has the advantages of good reliability, high lifting lift, good gas-water atomization and water slip-off prevention effect.

[0005] The application provides a multistage pneumatic jetting relay drainage gas recovery device, which is characterized by comprising a packer, a pressure-controlled switch jetting pump, a pneumatic jetting pump, a check valve, a tail pipe and a connecting pipe.

[0006] Preferably, the upper side of the power gas temporary storage cavity is provided with a conical cavity, the upper part of the conical cavity is communicated with the mixing energy conversion cavity through the gas jetting acceleration cavity, the gas jetting acceleration cavity is an annular cavity, and the gas jetting acceleration cavity is formed by the necked part of the outer wall of the central pipe and the inner wall of the pneumatic jetting pump body.

[0007] Preferably, the upper end of the pneumatic jetting pump body is provided with a pneumatic jetting pump upper connector, the pneumatic jetting pump upper connector is connected with the pressure-controlled switch jetting pump through the connecting pipe, the lower end of the pneumatic jetting pump lower connector is connected with the tail pipe through internal threads, and the outer threads are connected with the packer through a pipeline.

[0008] Preferably, the pressure-controlled switch jetting pump comprises a pressure-controlled switch jetting pump barrel, a pressure boosting cavity, a pump core, a mixing cavity, an acceleration cavity, a power gas inlet nozzle, a slide valve, a spring, an adjusting bottom ring and a pressure-controlled switch jetting pump lower connector, the inner cavity of the pressure-controlled switch jetting pump barrel is provided with the pump core, the pump core is movably connected to the adjusting bottom ring, the slide valve is arranged on the upper side of the adjusting bottom ring through the spring, the inner end of the plurality of power gas inlet nozzles arranged on the outer wall of the pressure-controlled switch jetting pump barrel is matched with the slide valve, so that the power gas inlet nozzle is opened and closed, the middle part of the pump core and the middle inner wall of the pressure-controlled switch jetting pump barrel form the acceleration cavity, the upper part of the pump core and the upper inner wall of the pressure-controlled switch jetting pump barrel form the mixing cavity and the pressure boosting cavity, and the bottom of the pressure-controlled switch jetting pump barrel is provided with the pressure-controlled switch jetting pump lower connector.

[0009] Preferably, the upper part of the pump core is in a solid structure, the lower part of the pump core is in a hollow structure, a plurality of liquid suction ports are arranged on the upper part of the hollow structure of the pump core in a uniform distribution mode, the outlet of the liquid suction port is located on the upper side outlet of the acceleration cavity, water from the hollow structure of the pump core is jetted through the power gas, the jetted gas-water mixture is in a mist shape, and the mixture reaches the ground along the oil pipe under the action of pressure energy and gas expansion energy.

[0010] Preferably, the top end of the pump core is provided with a conical head, the lower outer wall of the pump core is provided with a protruding mounting seat, and the bottom of the pump core is provided with an inlet end.

[0011] Preferably, the adjusting bottom ring is in a circular ring structure, the outer wall of the adjusting bottom ring is provided with threads, the threads are connected to the inner wall of the lower joint of the pressure-controlled switch jet pump, and the bottom of the adjusting bottom ring is provided with a rotating fixing block.

[0012] Preferably, the spool valve comprises a spool valve body, a limiting protrusion, a spool valve sealing surface, and a lower support end surface, the spool valve body is in a cylindrical structure, the lower part of the spool valve body is provided with an annular limiting protrusion, the outer wall of the spool valve body is the spool valve sealing surface, the lower end of the limiting protrusion is the lower support end surface, and a spring is installed below the lower support end surface.

[0013] The drainage and production method of the multi-stage pneumatic jet relay drainage and production device mentioned in the application comprises the following processes:

[0014] Firstly, the multi-stage pneumatic jet relay drainage and production device is assembled, a connecting pipe is connected between the lower end of the pressure-controlled switch jet pump and the pneumatic jet pump, a tail pipe is connected to the lower end of the pneumatic jet pump, a single-flow valve is installed in the tail pipe, the multi-stage pneumatic jet relay drainage and production device is lowered to the set position of the casing through the tubing at the wellhead on the ground, and the packer is set and sealed;

[0015] Secondly, at the wellhead on the ground, power gas is pumped into the annulus between the tubing and the casing, the stored water in the annulus between the tubing and the casing is moved downward under the pressure of the power gas, as the pressure of the power gas in the casing gradually increases, the spool valve in the pressure-controlled switch jet pump is opened, the water and the power gas enter the annulus between the pump cylinder and the pump core of the pressure-controlled switch jet pump along the power gas inlet nozzle, and then are injected through the acceleration cavity to modulate the water into a mist-shaped gas-water mixture, which moves upward along the mixing cavity and the pressure-increasing cavity and reaches the ground along the tubing under the action of the pressure energy and the expansion energy of the power gas.

[0016] As the power gas is continuously injected into the annulus between the tubing and the casing, the liquid level of the stored water in the annulus continues to drop, the density of the mixed liquid in the upper part of the pressure-controlled switch jet pump decreases as the proportion of the gas increases, and when the internal and external pressure difference tends to be balanced, the pressure of the power gas in the annulus between the tubing and the casing decreases, and the spool valve moves upward to be closed under the pressure of the spring.

[0017] At this time, the power gas continues to press the gas-water interface in the casing down along the annulus between the tubing and the casing, and as the pressure of the power gas in the annulus gradually increases, the power gas drives the stored water in the casing to enter the power gas temporary storage cavity through the power gas flow limiting ring hole of the lower gas jet pump, and then passes through the conical cavity and the gas jet acceleration cavity to upwardly inject the water from the center tube, and the power gas injection modulation gas-water atomized two-phase fluid upwardly passes through the mixing energy conversion cavity and the pressure boosting diffusion cavity, and then continues to upwardly along the connecting pipe to the pump core of the pressure control switch jet pump, and then upwardly discharges through the liquid suction port, and then is lifted to the ground through the tubing; when the density of the mixed gas at the ground wellhead is close to the density of the injected power gas, the power gas injection is stopped, and the gas well resumes self-flowing production under the action of the reservoir pressure;

[0018] III. As the self-flowing production proceeds, the water not taken out by the gas flow will gradually deposit at the bottom of the well, and when the gas production is significantly reduced and the stored water at the bottom of the well begins to block the gas production channel, the drainage operation needs to be performed again, and the above-mentioned drainage operation of process II is repeated to ensure the effective production of the gas well.

[0019] Compared with the prior art, the beneficial effects of the present application are as follows:

[0020] 1. The present application uses gas as a jet power medium to drive the pressure control switch jet pump and the gas jet pump to drain the liquid, organically combines gas relay jetting, gas lifting and gas expansion energy, injects and modulates the water at the bottom of the well into dispersed mist-shaped gas-water two-phase fluid to lift to the ground, has the characteristics of good reliability, high lifting head, good gas-water atomization and water slip prevention effect, wide applicable well condition range, high drainage efficiency, simple ground system matching, and recyclable power gas; both continuous drainage and intermittent drainage can be performed, the configuration level of the gas jet pump and the pressure control switch jet pump can be flexibly configured, the construction parameters can be optimally selected according to the specific well condition and the gas-water production ratio, and the setting interval of the components in the pipe string is optimally set according to the well condition and the gas-water production ratio, thereby providing a wider optional space for the reasonable configuration of the pipe string and the guarantee of the drainage efficiency;

[0021] 2. The pressure control switch jet pump and the gas jet pump of the present application have the advantages of novel and reliable structure, high pump efficiency, low manufacturing cost, low energy consumption, convenient operation, single-stage use or multi-stage series connection, and can be used in conjunction with a gas lifting valve to assist in starting lifting, which is more helpful to improve the lifting head, the drainage efficiency, the corrosion resistance and the service life of the drainage pipe string of the system, and has obvious advantages in the drainage of deep low-pressure gas wells. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 is the overall structure schematic diagram of embodiment 1 of the present application;

[0023] Figure 2 is a structural schematic diagram of the gas jet pump;

[0024] Figure 3 is the structural schematic diagram of the pressure-controlled switchable jet pump when the slide valve is closed;

[0025] Figure 4 is the structural schematic diagram of the pressure-controlled switchable jet pump when the slide valve is opened;

[0026] Figure 5 is the structural schematic diagram of the pump core of the pressure-controlled switchable jet pump;

[0027] Figure 6 is the structural schematic diagram of the slide valve of the pressure-controlled switchable jet pump;

[0028] Figure 7 is the overall structural schematic diagram of the embodiment 2 of the present application;

[0029] In the figure: casing 1, tubing 2, pressure-controlled switchable jet pump 3, pneumatic jet pump 4, check valve 5, packer 6, tail pipe 7, connecting pipe 8;

[0030] Pressure-controlled switchable jet pump barrel 3.1, pressure boosting chamber 3.2, pump core 3.3, mixing chamber 3.4, liquid suction port 3.5, acceleration chamber 3.6, power gas inlet nozzle 3.7, slide valve 3.8, spring 3.9, adjusting bottom ring 3.10, pressure-controlled switchable jet pump lower connector 3.11, conical head 3.3.1, solid structure 3.3.2, hollow structure 3.3.3, mounting seat 3.3.4, inlet end 3.3.5, slide valve main body 3.8.1, limiting protrusion 3.8.2, slide valve sealing surface 3.8.3, lower support end surface 3.8.4, rotary fixing block 3.10.1;

[0031] Pneumatic jet pump body 4.1, pressure boosting diffusion chamber 4.2, mixing energy conversion chamber 4.3, power gas flow limiting ring hole 4.4, pneumatic jet pump lower connector 4.5, power gas temporary storage chamber 4.6, center pipe 4.7, gas jet acceleration chamber 4.8, conical chamber 4.9, pneumatic jet pump upper connector 4.10, center pipe mounting base 4.11. DETAILED DESCRIPTION

[0032] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings, and it should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0033] Embodiment 1, refer to Figures 1-6The application relates to a multistage pneumatic jetting relay drainage gas recovery device, which comprises a packer 6, a pressure-controlled switch jetting pump 3, a pneumatic jetting pump 4, a check valve 5, a tail pipe 7 and a connecting pipe 8, wherein the pressure-controlled switch jetting pump 3 is connected to a tubing 2 and lowered into a casing 1 in a well, the lower end of the pressure-controlled switch jetting pump 3 is connected to the pneumatic jetting pump 4 through the connecting pipe 8, the lower end of the pneumatic jetting pump 4 is connected to the tail pipe 7, and the check valve 5 is arranged in the tail pipe 7; the pneumatic jetting pump 4 comprises a pneumatic jetting pump body 4.1, a pressure boosting diffusion cavity 4.2, a mixing energy conversion cavity 4.3, a power gas flow limiting ring hole 4.4, a pneumatic jetting pump lower connector 4.5, a power gas temporary storage cavity 4.6 and a central pipe 4.7, the outer wall of the lower middle part of the pneumatic jetting pump body 4.1 is provided with a plurality of power gas flow limiting ring holes 4.4, the inside of the pneumatic jetting pump body 4.1 is sequentially provided, from top to bottom, with the pressure boosting diffusion cavity 4.2, the mixing energy conversion cavity 4.3, a gas jetting acceleration cavity 4.8 and the power gas temporary storage cavity 4.6, the central pipe 4.7 is arranged in the center of the gas jetting acceleration cavity 4.8 and the power gas temporary storage cavity 4.6, the bottom of the central pipe 4.7 is movably connected in a central pipe mounting base 4.11, and the lower end of the pneumatic jetting pump body 4.1 is provided with the pneumatic jetting pump lower connector 4.5.

[0034] The upper side of the power gas temporary storage cavity 4.6 is provided with a tapered cavity 4.9, the upper part of the tapered cavity 4.9 is communicated with the mixing energy conversion cavity 4.3 through the gas jetting acceleration cavity 4.8, the gas jetting acceleration cavity 4.8 is an annular cavity, and the gas jetting acceleration cavity 4.8 is formed by the necked part of the outer wall of the central pipe 4.7 and the inner wall of the pneumatic jetting pump body 4.1.

[0035] The upper end of the pneumatic jetting pump body 4.1 is provided with a pneumatic jetting pump upper connector 4.10, the pneumatic jetting pump upper connector 4.10 is connected to the pressure-controlled switch jetting pump 3 through the connecting pipe 8, the lower end of the pneumatic jetting pump lower connector 4.5 is connected to the tail pipe 7 through internal threads, and the tail pipe 7 is connected to the packer 6 through external threads and pipelines.

[0036] Reference Figures 3-4The pressure-controlled switch jet pump 3 comprises a pressure-controlled switch jet pump cylinder 3.1, a pressure boosting chamber 3.2, a pump core 3.3, a mixing chamber 3.4, an acceleration chamber 3.6, a power gas inlet nozzle 3.7, a slide valve 3.8, a spring 3.9, an adjusting bottom ring 3.10, and a pressure-controlled switch jet pump lower connector 3.11.

[0037] Referring to Figure 5 The upper part of the pump core 3.3 is a solid structure 3.3.2, and the lower part is a hollow structure 3.3.3. A plurality of liquid suction ports 3.5 are arranged on the upper part of the hollow structure 3.3.3 of the pump core 3.3, and the outlets of the liquid suction ports 3.5 are located on the upper side of the acceleration chamber 3.6. The water in the hollow structure 3.3.3 of the pump core 3.3 is jetted by power gas to form a mist-shaped gas-water mixture, which reaches the ground along the oil pipe 2 under the action of pressure energy and gas expansion energy.

[0038] The top end of the pump core 3.3 is provided with a conical head 3.3.1, the lower outer wall of the pump core 3.3 is provided with a raised mounting seat 3.3.4, and the bottom of the pump core 3.3 is provided with an inlet end 3.3.5.

[0039] The adjusting bottom ring 3.10 is a circular ring structure, and a thread is arranged on the outer wall of the adjusting bottom ring 3.10. The adjusting bottom ring 3.10 is connected to the inner wall of the pressure-controlled switch jet pump lower connector 3.11 through the thread, and a rotating fixing block 3.10.1 is arranged on the bottom of the adjusting bottom ring 3.10.

[0040] Referring to Figure 6 The slide valve 3.8 comprises a slide valve body 3.8.1, a limiting protrusion 3.8.2, a slide valve sealing surface 3.8.3, and a lower support end surface 3.8.4. The slide valve body 3.8.1 is a cylindrical structure, and the lower part of the slide valve body 3.8.1 is provided with an annular limiting protrusion 3.8.2. The outer wall of the slide valve body 3.8.1 is the slide valve sealing surface 3.8.3, the lower end of the limiting protrusion 3.8.2 is the lower support end surface 3.8.4, and the spring 3.9 is arranged below the lower support end surface 3.8.4.

[0041] The drainage and production method of the multi-stage pneumatic jetting relay drainage and production device mentioned in the present application comprises the following processes:

[0042] I. First, assemble the multi-stage pneumatic jetting relay drainage and production device, connect the lower end of the pressure-controlled switch jetting pump 3 with the pneumatic jetting pump 4 through the connecting pipe 8, connect the lower end of the pneumatic jetting pump 4 with the tail pipe 7, install the one-way valve 5 in the tail pipe 7, lower the multi-stage pneumatic jetting relay drainage and production device into the set position of the casing 1 through the tubing 2 at the ground wellhead, and set the packer 6;

[0043] II. At the ground wellhead, pump the power gas into the annulus between the tubing 2 and the casing 1, the stored water between the tubing 2 and the casing 1 is moved downward under the pressure of the power gas, as the pressure of the power gas in the casing 1 gradually increases, the spool valve 3.8 in the pressure-controlled switch jetting pump 3 is opened, the water and the power gas enter the annulus between the pump cylinder 3.1 and the pump core 3.3 along the power gas inlet nozzle 3.7, then are injected through the annular acceleration cavity 3.6 to modulate the water into a misty gas-water mixture, which moves upward along the mixing cavity 3.4 and the pressure-increasing cavity 3.2, reaches the ground along the tubing 2 under the action of pressure energy and expansion energy of the power gas, avoids the gas-water slippage phenomenon of the existing gas lift valve, and improves the drainage efficiency;

[0044] As the power gas is continuously injected into the annulus between the tubing 2 and the casing 1, the liquid level of the stored water in the annulus continues to drop, the mixed liquid density at the upper part of the pressure-controlled switch jetting pump 3 decreases due to the increase of the gas proportion, when the internal and external pressure difference tends to be balanced, the pressure of the power gas in the annulus between the tubing 2 and the casing 1 decreases, and the spool valve 3.8 moves upward to be closed under the pressure of the spring 3.9;

[0045] At this time, the power gas continues to press the gas-water interface in the casing 1 downward along the annulus between the tubing 2 and the casing 1, as the pressure of the power gas in the annulus gradually increases, the stored water in the casing 1 is driven by the power gas to enter the power gas temporary storage cavity 4.6 through the power gas flow-limiting ring hole 4.4 of the lower pneumatic jetting pump 4, then passes through the conical cavity 4.9 and the gas jetting acceleration cavity 4.8 to move upward, injects the water from the central pipe 4.7, and forms a gas-water misting two-phase fluid which moves upward through the mixing energy conversion cavity 4.3 and the pressure-increasing diffusion cavity 4.2, then continues to move upward along the connecting pipe 8 to the pump core 3.3 of the pressure-controlled switch jetting pump 3, then moves upward through the liquid suction port 3.5, and is lifted to the ground through the tubing 2; when it is confirmed that the density of the mixed gas at the ground wellhead is close to the density of the injected power gas, stop pumping the power gas, and the gas well resumes production under the action of the reservoir pressure;

[0046] Three, with the self-flowing gas production, not by the water flow out of the well bottom will gradually deposited, when gas production is significantly reduced, and the water storage begins to block the gas production channel, need to carry out drainage construction, to repeat the above process two drainage operation, to ensure the effective production of gas well.

[0047] Embodiment 2, the application refers to a kind of multistage pneumatic jetting relay drainage gas recovery devices, including packer 6, also including pressure-controlled switch jet pump 3, pneumatic jet pump 4, check valve 5, tail pipe 7, connecting pipe 8, pressure-controlled switch jet pump 3 is connected through tubing 2 and is lowered into the casing 1 under the ground, pressure-controlled switch jet pump 3 is connected with pneumatic jet pump 4 at the lower end through connecting pipe 8, tail pipe 7 is connected at the lower end of pneumatic jet pump 4, single-flow valve 5 is installed in tail pipe 7;The pneumatic jet pump 4 includes pneumatic jet pump body 4.1, boost diffusion chamber 4.2, mixed energy conversion chamber 4.3, power gas limiting ring hole 4.4, pneumatic jet pump lower connector 4.5, power gas temporary storage chamber 4.6, center tube 4.7, the outer wall of the middle lower part of the pneumatic jet pump body 4.1 is provided with a plurality of power gas limiting ring hole 4.4, the inside of pneumatic jet pump body 4.1 is sequentially provided with boost diffusion chamber 4.2, mixed energy conversion chamber 4.3, gas jet acceleration chamber 4.8 and power gas temporary storage chamber 4.6 from top to bottom, center tube 4.7 is installed in the center of gas jet acceleration chamber 4.8 and power gas temporary storage chamber 4.6, and the bottom of center tube 4.7 is movably connected in center tube installation base 4.11, the lower end of pneumatic jet pump body 4.1 is provided with pneumatic jet pump lower connector 4.5.

[0048] The difference between embodiment 1 is:

[0049] Reference Figure 7 The pressure-controlled switch jet pump 3 referred to in the embodiment can have two stages according to the conditions under the ground, the spring forces of the springs 3.9 under the spools 3.8 of the two stages are different, so as to respectively control the alternate opening and closing of the spools 3.8, and sequentially inject and modulate the water stored at the well bottom into dispersed mist-shaped gas-water two-phase fluid until the fluid is lifted to the ground, which has the advantages of good reliability, high lifting head, good gas-water atomization and water slip prevention effect.

[0050] The above is only part of the preferred embodiments of the application, and any person skilled in the art can modify the above-described technical solutions or modify them into equivalent technical solutions. Therefore, the corresponding simple modifications or equivalent transformations according to the technical solutions of the application are within the scope of protection claimed by the application.

Claims

1. A multi-stage pneumatic jet relay drainage and gas extraction device, comprising a packer (6), characterized in that: It also includes a pressure-controlled switch jet pump (3), a pneumatic jet pump (4), a check valve (5), a tailpipe (7), and a connecting pipe (8). The pressure-controlled switch jet pump (3) is connected to the casing (1) that is lowered into the well via an oil pipe (2). The lower end of the pressure-controlled switch jet pump (3) is connected to the pneumatic jet pump (4) via the connecting pipe (8). The lower end of the pneumatic jet pump (4) is connected to the tailpipe (7), and a check valve (5) is installed inside the tailpipe (7). The pneumatic jet pump (4) includes a pneumatic jet pump body (4.1), a pressure-boosting diffusion chamber (4.2), a mixing and energy-transferring chamber (4.3), a power gas flow-limiting ring hole (4.4), a pneumatic jet pump lower connector (4.5), and a power gas temporary storage chamber (4.5). 4.6), Central tube (4.7), the outer wall of the middle and lower part of the pneumatic jet pump body (4.1) is provided with multiple power gas flow limiting ring holes (4.4), the interior of the pneumatic jet pump body (4.1) is provided with a pressure boosting diffusion chamber (4.2), a mixing energy transducer chamber (4.3), a gas jet acceleration chamber (4.8) and a power gas storage chamber (4.6) from top to bottom, the central tube (4.7) is installed in the center of the gas jet acceleration chamber (4.8) and the power gas storage chamber (4.6), and the bottom of the central tube (4.7) is movably connected in the central tube mounting base (4.11), the lower end of the pneumatic jet pump body (4.1) is provided with a pneumatic jet pump lower connector (4.5); The pressure-controlled switch injection pump (3) includes a pressure-controlled switch injection pump barrel (3.1), a boosting chamber (3.2), a pump core (3.3), a mixing chamber (3.4), an acceleration chamber (3.6), a power air inlet nozzle (3.7), a slide valve (3.8), a spring (3.9), an adjusting bottom ring (3.10), and a pressure-controlled switch injection pump lower connector (3.11). The pump core (3.3) is installed in the inner cavity of the pressure-controlled switch injection pump barrel (3.1), and the pump core (3.3) is movably connected to the adjusting bottom ring (3.10). The slide valve (3.8) is installed on the upper side of the adjusting bottom ring (3.10) via the spring (3.9). 8) The opening and closing of the power air inlet nozzles (3.7) are realized by the cooperation of the slide valve (3.8) with the inner end of the multiple power air inlet nozzles (3.7) provided on the outer wall of the pressure-controlled switch jet pump barrel (3.1); the middle part of the pump core (3.3) and the middle inner wall of the pressure-controlled switch jet pump barrel (3.1) form an acceleration chamber (3.6); the upper part of the pump core (3.3) and the upper inner wall of the pressure-controlled switch jet pump barrel (3.1) form a mixing chamber (3.4) and a pressure boosting chamber (3.2); the bottom of the pressure-controlled switch jet pump barrel (3.1) is provided with a pressure-controlled switch jet pump lower connector (3.11).

2. The multi-stage pneumatic jet relay drainage and gas extraction device according to claim 1, characterized in that: The upper side of the power gas storage chamber (4.6) is provided with a conical cavity (4.9). The upper part of the conical cavity (4.9) is connected to the mixing transducer chamber (4.3) through the gas injection acceleration chamber (4.8). The gas injection acceleration chamber (4.8) is an annular cavity, and the gas injection acceleration chamber (4.8) is formed by the constriction of the outer wall of the central tube (4.7) and the inner wall of the pneumatic injection pump body (4.1).

3. The multi-stage pneumatic jet relay drainage and gas extraction device according to claim 2, characterized in that: The upper end of the pneumatic jet pump body (4.1) is provided with a pneumatic jet pump upper connector (4.10), which is connected to the pressure-controlled switch jet pump (3) through a connecting pipe (8); the lower end of the pneumatic jet pump lower connector (4.5) is connected to the tail pipe (7) through an internal thread, and the external thread is connected to the packer (6) through a pipeline.

4. The multi-stage pneumatic jet relay drainage and gas extraction device according to claim 3, characterized in that: The upper part of the pump core (3.3) is a solid structure (3.3.2), and the lower part is a hollow structure (3.3.3). Multiple evenly distributed suction ports (3.5) are provided on the upper part of the hollow structure (3.3.3) of the pump core (3.3). The outlet of the suction port (3.5) is located on the upper outlet of the acceleration chamber (3.6). Water from the hollow structure (3.3.3) of the pump core (3.3) is injected by power air and sprayed into a mist-like gas-water mixture. Under the dual action of pressure energy and gas expansion energy, it reaches the ground along the oil pipe (2).

5. The multi-stage pneumatic jet relay drainage and gas extraction device according to claim 4, characterized in that: The pump core (3.3) has a tapered head (3.3.1) at the top, a protruding mounting seat (3.3.4) on the lower outer wall of the pump core (3.3), and an inlet end (3.3.5) at the bottom of the pump core (3.3).

6. The multi-stage pneumatic jet relay drainage and gas extraction device according to claim 5, characterized in that: The adjusting bottom ring (3.10) is a circular ring structure. The outer wall of the adjusting bottom ring (3.10) is threaded and connected to the inner wall of the lower connector (3.11) of the pressure control switch injection pump through the thread. The bottom of the adjusting bottom ring (3.10) is provided with a rotating fixing block (3.10.1).

7. The multi-stage pneumatic jet relay drainage and gas extraction device according to claim 6, characterized in that: The slide valve (3.8) includes a slide valve body (3.8.1), a limiting protrusion (3.8.2), a slide valve sealing surface (3.8.3), and a lower support end face (3.8.4). The slide valve body (3.8.1) is a cylindrical structure. The lower part of the slide valve body (3.8.1) is provided with an annular limiting protrusion (3.8.2). The outer wall of the slide valve body (3.8.1) is the slide valve sealing surface (3.8.3). The lower end of the limiting protrusion (3.8.2) is the lower support end face (3.8.4). The spring (3.9) is installed below the lower support end face (3.8.4).

8. A drainage and gas extraction method using the multi-stage pneumatic jet relay drainage and gas extraction device as described in claim 7, characterized in that: Includes the following processes: First, assemble the multi-stage pneumatic jet relay drainage and gas production device. Connect the lower end of the pressure-controlled switch jet pump (3) to the pneumatic jet pump (4) through the connecting pipe (8). Connect the lower end of the pneumatic jet pump (4) to the tail pipe (7). Install a single-flow valve (5) inside the tail pipe (7). At the wellhead on the ground, lower the multi-stage pneumatic jet relay drainage and gas production device into the set position of the casing (1) through the oil pipe (2) and set the packer (6).

2. At the wellhead on the ground, power gas is pumped into the annulus between the tubing (2) and the casing (1). The power gas presses down and moves the water in the annulus between the tubing (2) and the casing (1) downward. As the pressure of the power gas in the casing (1) gradually increases, the slide valve (3.8) in the pressure-controlled switch jet pump (3) opens. Water and power gas enter the annulus between the pump barrel (3.1) and the pump core (3.3) of the pressure-controlled switch jet pump along the power gas inlet nozzle (3.7). After being ejected through the acceleration chamber (3.6), the water jet is modulated into a mist-like gas-water mixture. It moves upward along the mixing chamber (3.4) and the pressure-boosting chamber (3.2). Under the action of pressure energy and the expansion energy of the power gas, it reaches the ground along the tubing (2). As power gas is continuously injected into the annulus of the tubing (2) and casing (1), the water level in the annulus continues to drop. The density of the mixture above the pressure-controlled switch jet pump (3) decreases due to the increase in the gas ratio. When the internal and external pressure difference tends to be balanced, the pressure of the power gas in the annulus of the tubing (2) and casing (1) decreases, and the slide valve (3.8) moves upward under the pressure of the spring (3.9) to close the slide valve (3.8). At this time, the power gas continues to descend along the annulus between the oil pipe (2) and the casing (1) to the gas-water interface inside the casing (1). As the pressure of the power gas in the annulus gradually increases, the power gas drives the water stored in the casing (1) through the power gas flow-limiting annulus (4.4) of the lower pneumatic jet pump (4) into the power gas storage chamber (4.6), and then through the conical chamber (4.9) and the gas jet acceleration chamber (4.8) upwards, drawing water from the central pipe (4.7) and through the power... The gas ejector modulates the gas-water atomized two-phase fluid upward through the mixing transducer chamber (4.3) and the pressure-boosting diffusion chamber (4.2), and then continues upward along the connecting pipe (8) to the pump core (3.3) of the pressure-controlled switch jet pump (3), and then is discharged upward through the suction port (3.5), and then lifted to the ground through the oil pipe (2); when it is confirmed that the density of the mixed gas at the wellhead is close to the density of the injected power gas, the pumping of power gas is stopped, and the gas well resumes self-flowing gas production under the action of reservoir pressure; Third, as the gas production proceeds, the water that is not carried out by the gas flow will gradually accumulate at the bottom of the well. When the gas production decreases significantly and the water at the bottom of the well begins to block the gas production channel, and drainage construction is required, the drainage operation in step two above will be repeated to ensure the effective production of the gas well.

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