Gas well single-pipe jet pump drainage and mining device and using method thereof

Abstract

The invention discloses a gas well single-pipe jet pump drainage and mining device which comprises a jet pump cylinder, a jet pump core is mounted in the jet pump cylinder, the top of the jet pump cylinder is connected with an oil pipe, and a casing packer is arranged at the bottom of the jet pump cylinder and connected with a casing. The invention further discloses a using method of the gas well single-pipe jet pump drainage and mining device. The using method comprises the steps that the casing packer is put down; a lower jet pump cylinder; a packer plug is removed; putting a jet pump core; and fishing the jet pump core. The invention solves the problems of complex process and high operation cost caused by pulling out the original production string in the well by the existing jet pump drainage and mining process.

Description

Technical Field

[0001] This invention belongs to the field of natural gas field development technology, specifically relating to a gas well single-tube jet pump drainage device, and further relating to the method of using the gas well single-tube jet pump drainage device. Background Technology

[0002] To quickly and effectively remove formation water and wellbore fluid, restore or maintain stable gas well production over a longer period, and improve the recovery rate of water-bearing gas reservoirs, it is necessary to adopt drainage and gas production techniques in a timely manner to reduce the impact of fluid accumulation. As gas field development progresses, formation pressure continues to decrease, and the number of producing gas wells increases. Currently, the approach to producing gas wells is gradually shifting from self-flowing production to drainage and gas production relying on external energy. However, the external energy drainage and gas production process suffers from severe wear and tear on mechanical moving parts due to impurities such as fracturing sand and coal dust carried by the fluid, ultimately resulting in poor performance.

[0003] Jet pump drainage technology offers advantages such as good anti-erosion performance, long flow components, simple structure, ease of manufacturing, and stable operation. It is suitable for conveying gas-liquid two-phase mixtures and has become the primary external energy lift method in major gas and coalfields in China. However, due to the instability of the wellbore's full-bore integrity during jet pump drainage, jet pump drainage components are generally not installed during self-flowing gas well production. Only when the formation pressure drops to a level requiring external energy jet pump drainage is the original production tubing removed, the jet pump drainage components installed, and re-installed, resulting in complex processes and high operating costs. Summary of the Invention

[0004] One objective of this invention is to provide a single-tube jet pump drainage device for gas wells, which solves the problems of complex processes and high operating costs caused by the existing jet pump drainage process for retrieving the original production tubing from the well.

[0005] Another object of the present invention is to provide a method of using a gas well single-tube jet pump drainage device.

[0006] One technical solution adopted in this invention is a gas well single-tube jet pump drainage device, including a jet pump barrel, a jet pump core installed inside the jet pump barrel, an oil pipe connected to the top of the jet pump barrel, a casing packer installed at the bottom of the jet pump barrel, and the casing packer connected to the casing.

[0007] The jet pump barrel includes a pump barrel body, with connecting pipes and sealing sections connected to both ends of the pump barrel body by threads, and an inner cavity opened on one side of the pump barrel body.

[0008] The invention is further characterized in that the jet pump core includes a pump core body, with connecting section a and connecting section b connected to both ends of the pump core body via threads. A throat and a diffuser are sequentially installed inside the pump core body. Connecting section a is connected to the retrieval neck via threads, and a nozzle is secured to the bottom of the retrieval neck by a gasket. An air inlet is provided on connecting section a, facing the outlet of the nozzle. The nozzle throttles and reduces the pressure of the fluid injected into the production tubing at the wellhead. The pump core body is connected to connecting section b via threads, and a gasket seals the connection between the pump core body and connecting section b. Connecting section b is connected to the mixed fluid return outlet section via threads, and an air outlet is provided on one side of the mixed fluid return outlet section.

[0009] The retrieval neck, nozzle, throat, diffuser, pump core body, and mixed fluid return outlet section are opened along the longitudinal extension direction to form a fluid channel. Connecting sections a and b are snapped into the connecting pipe. The inner wall of the connecting pipe and the outer wall of the pump core body form an annular space. The throat creates a low-pressure zone for the high-pressure gas after throttling and depressurization. The diffuser repressurizes the fluid in the well after mixing with the low-pressure gas, and lifts it to the surface through the gas outlet of the mixed fluid return outlet section via the annulus.

[0010] Sealing rings are installed on the salvage neck, the mixed fluid return outlet section, and the sealing section.

[0011] Another technical solution adopted in this invention is a method for using a single-tube jet pump drainage device for gas wells, which is implemented according to the following steps:

[0012] Step 1, install the casing packer;

[0013] Step 2, lower the jet pump barrel;

[0014] Step 3: Remove the packer plug;

[0015] Step 4: Dispense the jet pump core;

[0016] Step 5: Retrieve the jet pump core.

[0017] The invention is further characterized by taking a single-tube jet pump drainage process for a gas well as an example, and implementing it according to the following steps:

[0018] Step 1, install the casing packer;

[0019] Under pressure, the packer with plug is lowered into the corresponding position inside the casing via a cable to complete the slip anchoring and rubber sleeve sealing, thereby achieving upper and lower sealing of the packer inside the casing and ensuring that the tool does not move up or down.

[0020] Step 2, lower the jet pump barrel;

[0021] Under pressure, the jet pump barrel is connected to the end of the production tubing and lowered into the casing until the sealing section 11 is inserted into the inner cavity of the packer body. At the same time, the sealing section seal ring completes the sealing. After the tubing is lowered, the production tubing is suspended at the wellhead and the gas production tree is installed.

[0022] Step 3: Remove the packer plug;

[0023] A compressor is used to inject nitrogen or natural gas into the production tubing through the main bore of the wellhead until the packer plug falls off. When the well pressure is high, the well can be opened directly to achieve self-flowing fluid production.

[0024] Step 4: Dispense the jet pump core;

[0025] When the gas well pressure drops and self-flowing fluid production cannot be achieved, under pressurized conditions, the jet pump core is manually inserted into the jet pump barrel through the main bore of the gas tree and the production tubing; on the surface, a compressor is used to inject the wellhead fluid through the main bore of the gas tree into the production tubing until it reaches the jet pump core. Under the action of pressure difference, the jet pump core is completely in place, and the sealing ring on the neck and the mixed fluid return outlet section achieves fluid isolation between the jet pump core and the jet pump barrel;

[0026] The surface compressor continuously injects fluid into the wellhead. When the high-pressure fluid passes through the nozzle of the jet pump core, the pressure drops sharply due to the throttling effect of the nozzle, forming a low-pressure zone around the nozzle.

[0027] Under the influence of pressure differential, the fluid in the well enters the "negative pressure" zone and mixes with the high-speed fluid at the nozzle outlet before entering the throat and diffuser. The mixed fluid in the diffuser is pressurized again and lifted to the surface by the annulus through the air outlet of the mixed fluid return outlet section.

[0028] Step 5: Retrieve the jet pump core;

[0029] Once the accumulated liquid in the well has been drained or the nozzle size needs to be changed, the jet pump core is removed from the well using wireline operations. The gas well can then continue to produce liquid by its own energy or by continuing to produce liquid by the jet pump.

[0030] The beneficial effects of this invention are as follows: The single-tube jet pump drainage device for gas wells has a simple tubing structure, is easy to construct, and meets the requirements of self-flowing during high-pressure periods and jet pump drainage during low-pressure periods, realizing the integration of jet pump drainage and production in gas wells; it eliminates the need to move the gas well production tubing, and the jet pump core is manually placed into the pump barrel, making operation convenient; when jet pump drainage is no longer needed after draining the accumulated liquid in the wellbore, the jet pump core can be retrieved from the well simply by using a wireline. This invention's single-tube jet pump drainage device for gas wells has advantages such as low investment, low management and maintenance costs, and high utilization rate. Attached Figure Description

[0031] Figure 1This is a schematic diagram of the jet pump core structure of the present invention;

[0032] Figure 2 This is a schematic diagram of the jet pump barrel structure of the present invention;

[0033] Figure 3 This is a schematic diagram of the casing packer structure of the present invention;

[0034] Figure 4 This is a schematic diagram of the internal structure of the jet pump barrel insertion sleeve packer of the present invention;

[0035] Figure 5 This is a schematic diagram of the structure for removing the plug of the sleeve packer in this invention;

[0036] Figure 6 This is a schematic diagram of the jet pump core of the present invention being placed inside the pump barrel.

[0037] In the figure, 1. Salvage neck, 2. Connecting section a, 3. Nozzle, 4. Throat, 5. Diffuser, 6. Pump core body, 7. Connecting section b, 8. Mixed fluid return outlet section, 9. Connecting pipe, 10. Pump barrel body, 11. Sealing section, 12. Sleeve packer. Detailed Implementation

[0038] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0039] Example 1

[0040] The present invention relates to a gas well single-tube jet pump drainage device, comprising a jet pump barrel, a jet pump core installed inside the jet pump barrel, an oil pipe connected to the top of the jet pump barrel, and a casing packer 12 installed at the bottom of the jet pump barrel, the casing packer 12 being connected to the casing.

[0041] like Figure 1 and Figure 2 As shown, the jet pump barrel includes a pump barrel body 10. The two ends of the pump barrel body 10 are respectively connected to a connecting pipe 9 and a sealing section 11 by threads. An inner cavity is opened on one side of the pump barrel body 10.

[0042] The jet pump core includes a pump core body 6. Both ends of the pump core body 6 are connected to connecting section a2 and connecting section b7 via threads. A throat tube 4 and a diffuser tube 5 are sequentially installed inside the pump core body 6. Connecting section a2 is connected to the retrieval neck 1 via threads. The bottom of the retrieval neck 1 is secured to the nozzle 3 via a gasket. An air inlet is provided on connecting section a2, facing the outlet of nozzle 3. Nozzle 3 throttles and reduces the pressure of the fluid injected into the production tubing at the wellhead. The pump core body 6 is connected to connecting section b7 via threads, and a gasket seals the connection between the pump core body 6 and connecting section b7. Connecting section b7 is connected to the mixed fluid return outlet section 8 via threads, and an air outlet is provided on one side of the mixed fluid return outlet section 8.

[0043] The wellbore fluid is channeled longitudinally through the following components: neck 1, nozzle 3, throat 4, diffuser 5, pump core body 6, and mixed fluid return outlet section 8. Connecting sections a2 and b7 are fitted into connecting pipe 9. The inner wall of connecting pipe 9 and the outer wall of pump core body 6 form an annular space. The throat 4 creates a low-pressure zone for the high-pressure gas after throttling and depressurization, allowing the wellbore fluid to reach the low-pressure zone through the pump cylinder cavity and the air inlet on connecting section a2. The diffuser 5 repressurizes the wellbore fluid after mixing with the low-pressure gas and lifts it to the surface through the air outlet of the mixed fluid return outlet section 8 via the annulus.

[0044] Example 2

[0045] Sealing rings are installed on the salvage neck 1, the mixed fluid return outlet section 8, and the sealing section 11.

[0046] like Figure 3 As shown, the casing packer 12 includes a packer body, slips, and a rubber sleeve. The bottom of the packer body has a plug, and the slips are anchored inside the casing to ensure that the casing packer 12 does not move up and down. The rubber sleeve achieves an effective seal between the casing and the casing packer 12. The casing packer 12 isolates the annulus of the casing from the bottom of the well, forming an independent fluid channel.

[0047] Example 3

[0048] The method of using the gas well single-tube jet pump drainage device of the present invention is implemented according to the following steps:

[0049] Step 1, lower the casing packer 12;

[0050] Step 2, lower the jet pump barrel;

[0051] Step 3: Remove the packer plug;

[0052] Step 4: Dispense the jet pump core;

[0053] Step 5: Retrieve the jet pump core.

[0054] Example 4

[0055] The method of using the gas well single-tube jet pump drainage device of the present invention, taking the gas well single-tube jet pump drainage process as an example, is implemented according to the following steps:

[0056] Step 1, lower the casing packer 12;

[0057] Under pressure, the bushing packer 12 with the plug is lowered into the corresponding position inside the bushing via a cable to complete the slip anchoring and rubber sleeve sealing, thereby achieving the upper and lower sealing of the packer inside the bushing and ensuring that the bushing packer 12 does not move up and down.

[0058] Step 2, lower the jet pump barrel;

[0059] Under pressure, the jet pump barrel is connected to the end of the production tubing and lowered into the casing until the sealing section 11 is inserted into the inner cavity of the packer body. Figure 4 As shown, the sealing is completed simultaneously through the sealing ring of sealing section 11. After the tubing string is lowered, the production tubing string is suspended at the wellhead and the gas production tree is installed.

[0060] Step 3: Remove the packer plug;

[0061] like Figure 5 As shown, a compressor is used to inject nitrogen or natural gas into the production tubing through the main bore of the gas production tree until the packer plug falls off. When the gas well pressure is high, the well is directly opened to achieve self-flowing fluid production.

[0062] Step 4: Dispense the jet pump core;

[0063] like Figure 6 As shown, when the gas well pressure is reduced and self-flowing fluid production cannot be achieved, under pressurized conditions, the jet pump core is manually inserted into the jet pump barrel through the main bore of the gas production tree and the production tubing; on the surface, a compressor is used to inject the wellhead fluid through the main bore of the gas production tree into the production tubing until it reaches the jet pump core. Under the action of pressure difference, the jet pump core is completely in place, and the sealing ring on the neck 1 and the mixed fluid return outlet section 8 achieves fluid isolation between the jet pump core and the jet pump barrel.

[0064] The surface compressor continuously injects fluid into the wellhead. When the high-pressure fluid passes through the nozzle 3 of the jet pump core, the pressure drops sharply due to the throttling effect of the nozzle 3, forming a low-pressure zone around the nozzle 3.

[0065] Under the action of pressure difference, the fluid in the well enters the "negative pressure" zone through the air inlet of the pump barrel cavity and the connecting section a2, and mixes with the high-speed fluid at the nozzle 3 outlet before entering the throat 4 and diffuser 5. The mixed fluid in the diffuser 5 is pressurized again and is lifted to the ground by the annulus through the air outlet of the mixed fluid return outlet section 8.

[0066] Step 5: Retrieve the jet pump core;

[0067] After the accumulated liquid in the well is drained or the nozzle needs to be replaced, the jet pump core is pulled out of the well using a wireline operation. The gas well can then continue to produce liquid by its own energy or by continuing to produce liquid by the jet pump.

[0068] The single-tube jet pump drainage device for gas wells of this invention features a simple tubing structure, facilitating construction. It meets the requirements of self-flowing during high-pressure periods and jet pump drainage during low-pressure periods, achieving integrated jet pump drainage and production. It eliminates the need to move the gas well production tubing; the jet pump core is manually placed into the pump barrel, making operation convenient. When jet pump drainage is no longer required after draining accumulated fluid from the wellbore, the jet pump core can be easily retrieved using wireline operations. This single-tube jet pump drainage device for gas wells of this invention offers advantages such as low investment, low management and maintenance costs, and high utilization rate. It is a single-tube jet pump drainage device implemented within the existing wellbore without requiring the removal of the original production tubing.

Claims

1. A single tube jet pump displacement device for gas wells, characterized in that, The jet pump pump barrel is internally provided with a jet pump pump core, the top of the jet pump pump barrel is connected with an oil pipe, and the bottom of the jet pump pump barrel is provided with a casing packer (12) connected with a casing.

2. The gas well single pipe jet pump drainage device according to claim 1, characterized in that, The jet pump pump barrel comprises a pump barrel body (10), the two ends of the pump barrel body (10) are respectively connected with a connecting pipe (9) and a sealing section (11) through threads, and an inner cavity is formed in one side of the pump barrel body (10).

3. The gas well single pipe jet pump drainage device according to claim 2, characterized in that, The jet pump pump core comprises a pump core body (6), the two ends of the pump core body (6) are respectively connected with a connecting section a (2) and a connecting section b (7) through threads, and a throat pipe (4) and a diffusion pipe (5) are sequentially arranged in the pump core body (6); the connecting section a (2) is connected with a fishing neck (1) through a thread, the bottom of the fishing neck (1) is clamped with a nozzle (3) through a gasket, an air inlet hole is formed in the connecting section a (2) and faces the outlet of the nozzle (3), the pump core body (6) is connected with the connecting section b (7) through a thread, and the pump core body (6) and the connecting section b (7) are sealed through a gasket; the connecting section b (7) is connected with a mixed fluid return outlet section (8) through a thread, and the mixed fluid return outlet section (8) is provided with an air outlet hole in one side.

4. The gas well single pipe jet pump drainage device according to claim 3, characterized in that, The fishing neck (1), the nozzle (3), the throat pipe (4), the diffusion pipe (5), the pump core body (6) and the mixed fluid return outlet section (8) are provided with fluid channels in the longitudinal extension direction, the connecting section a (2) and the connecting section b (7) are clamped in the connecting pipe (9), the inner wall of the connecting pipe (9) and the outer wall of the pump core body (6) form an annular space, the throat pipe (4) forms a low-pressure area for high-pressure gas after pressure reduction, the diffusion pipe (5) re-pressurizes the mixed fluid in the well and the low-pressure gas, and the mixed fluid is lifted to the ground through the air outlet hole of the mixed fluid return outlet section (8) and the oil-casing annulus.

5. The gas well single pipe jet pump drainage device according to claim 4, characterized in that, Sealing rings are arranged on the fishing neck (1), the mixed fluid return outlet section (8) and the sealing section (11).

6. The method for using the single tube jet pump displacement device for gas well, characterized in that, The method is implemented according to the following steps: Step 1, lower the casing packer (12); Step 2, lower the jet pump pump barrel; Step 3, remove the packer plug; Step 4, place the jet pump pump core; Step 5, fish the jet pump pump core.

7. The method according to claim 6, wherein, Taking a single-pipe jet pump drainage process of a gas well as an example, the method is implemented according to the following steps: Step 1, lower the casing packer (12); Under the pressure environment, the casing packer (12) with a plug is lowered into the casing at the corresponding position through a cable, the slip anchor and the rubber cylinder are sealed, the casing packer (12) is sealed in the casing, the casing packer (12) is not moved up and down, and the casing packer (12) is not moved up and down. Step 2, lower the jet pump pump barrel; Under the pressure environment, the jet pump pump barrel is connected at the tail end of the production pipe column and is lowered into the casing until the sealing section (11) is inserted into the inner cavity of the packer body, the sealing is completed through the sealing ring of the sealing section (11), after the pipe column is lowered, the production pipe column is hung at the wellhead and the gas production tree is installed; Step 3, remove the packer plug; The nitrogen or natural gas is injected into the production pipe column through the main passage of the gas production tree by using a compressor until the packer plug is removed, when the gas well pressure is high, the well is directly opened to realize the self-flowing liquid drainage production; Step 4, place the jet pump pump core; When the gas well pressure is reduced and self-flowing production cannot be achieved, the jet pump core is manually put into the jet pump cylinder through the main passage of the gas tree and the tubing string in the pressure environment; the ground uses a compressor to inject wellhead fluid into the production string through the main passage of the gas tree until the jet pump core is completely in place under the action of pressure difference, and the fishing neck (1) and the sealing ring on the mixed fluid return outlet section (8) realize the fluid isolation between the jet pump core and the jet pump cylinder. The ground compressor continuously injects wellhead fluid, and when the high-pressure fluid passes through the nozzle (3) of the jet pump core, the pressure drops sharply due to the throttling effect of the nozzle (3), forming a low-pressure area around the nozzle (3). Under the action of pressure difference, the fluid in the well enters the "negative pressure" area through the intake hole on the inner cavity of the pump cylinder and the connecting section a (2), and after mixing with the high-speed fluid at the outlet of the nozzle (3), it enters the throat (4) and the diffuser pipe (5), and the mixed fluid in the diffuser pipe (5) is pressurized again and lifted to the ground through the gas outlet hole of the mixed fluid return outlet section (8) through the oil jacket annulus. Step 5, fishing the jet pump core. When the wellbore fluid is removed or the nozzle (3) size needs to be replaced, the jet pump core is pulled out of the well through wireline operation, and the gas well continues to rely on its own energy to achieve self-flowing production or continues to use jet pump to produce.

Images