Discharging and mining system and method of jet pump with immovable string

Abstract

The invention relates to an immovable string jet pump drainage and mining system and method, and the system comprises a plunger pump, an oil pipe communicated with the plunger pump, a sleeve arranged outside the oil pipe in a sleeving manner, and a sitting jet pump; the jet pump is installed at the end, located at the well bottom, of the oil pipe in a setting mode, a plurality of open holes are annularly formed in the installation position, close to the jet pump, of the oil pipe, and the plunger pump is used for injecting power liquid into the oil pipe. The jet pump provided by the invention is installed on an oil pipe in a setting manner, so that the full-bore integrity of a shaft is high, and the jet pump has the advantages of low investment, low management and maintenance cost, high equipment utilization rate and the like; secondly, when the jet pump is installed, an original gas well underground production oil pipe does not need to be moved, oil pipe tapping is achieved through a low-cost rope operation measure, the cost of well killing and oil pipe lifting in a conventional measure is greatly reduced, and the jet pump is installed in the oil pipe through the low-cost rope operation measure.

Description

Technical Field

[0001] The invention belongs to the technical field of natural gas field exploitation, and in particular relates to a fixed pipe column jet pump drainage system and method. Background Art

[0002] At present, most of the gas fields that have been developed at home and abroad are elastic water-driven gas fields with low porosity and low permeability. As the development of gas reservoirs enters the middle and late stages, the formation pressure decreases, which will cause the edge water to advance and the bottom water to rise. When water appears in the gas reservoir, it will have a huge impact on the gas well production capacity. If the produced water cannot be discharged in time, it will accumulate at the bottom of the well, increase the bottom well back pressure, reduce the gas production, and in severe cases cause the gas well to be flooded and shut down. Long-term immersion in accumulated liquid will also cause great pollution and damage to the formation, resulting in a reduction in the final recovery rate of the gas reservoir and the overall development benefits. In order to quickly and effectively remove formation water and wellbore accumulated liquid, restore or maintain stable production of gas wells for a long period of time, and improve the recovery rate of water-bearing gas reservoirs, it is necessary to take timely drainage and gas production process measures to reduce the impact of accumulated liquid on it.

[0003] As gas field exploitation deepens, formation pressure continues to decrease, and the number of gas wells producing liquid increases. The current way to treat liquid-producing gas wells is to gradually change from self-flowing exploitation to relying on external energy to drain gas. However, the external energy drainage process causes serious wear of mechanical moving parts due to the fluid carrying impurities such as fracturing sand and coal powder, and the final effect is not good. The jet pump drainage process has the advantages of good anti-abrasion effect, long flow parts, simple structure, easy manufacturing, and stable operation. It is suitable for conveying gas-liquid two-phase mixed fluids and has become the most important external energy lifting method for major domestic large gas fields and coal fields.

[0004] Since the integrity of the full bore of the wellbore is not strong when the jet pump drainage process is implemented, the jet pump drainage process components are generally not installed when the gas well is produced by self-flowing. When the formation pressure drops to the point where the jet pump can be used for drainage with external energy, the original production tubing in the well is removed and the jet pump drainage process components are installed and lowered back into the well, which results in complex processes, high operating costs and other problems. Summary of the invention

[0005] In response to the above problems, the present invention provides a fixed tubing jet pump production system and method to solve the problem that when the existing jet pump production process is implemented, the full-diameter integrity of the wellbore is not strong and it is not suitable for installation during production, so as to achieve the purpose of installing the jet pump during production and reducing investment as well as management and maintenance costs.

[0006] One object of the present invention is achieved by the following technical solutions:

[0007] A fixed pipe column jet pump drainage system, comprising a plunger pump, an oil pipe connected to the plunger pump, a casing sleeved outside the oil pipe, and a sitting jet pump;

[0008] The jet pump is installed at one end of the oil pipe at the bottom of the well, and the oil pipe is provided with a plurality of openings around the installation position of the jet pump;

[0009] The plunger pump is used to inject power fluid into the oil pipe;

[0010] The oil pipe is used to transport the power fluid to the jet pump;

[0011] The jet pump is used for jetting power fluid to generate negative pressure to suck bottom hole fluid, and for lifting the mixed fluid.

[0012] Further, the jet pump comprises a body;

[0013] The body is a cavity structure, and the cavity of the body is divided into a first inlet cavity, a negative pressure cavity, a pressure diffusion cavity, and a second inlet cavity from top to bottom, and the negative pressure cavity is connected to the pressure diffusion cavity;

[0014] A nozzle is provided at the connection point between the first inlet chamber and the negative pressure chamber;

[0015] The body is provided with a well fluid inlet on the annular wall of the negative pressure chamber, and the well fluid inlet communicates with the negative pressure chamber and the second inlet chamber;

[0016] The main body is provided with a mixed fluid outlet on the annular wall of the diffusion chamber.

[0017] Furthermore, the body is provided with a first sealing member and a second sealing member on both sides of the mixed fluid outlet.

[0018] Furthermore, a slip is arranged on the outer peripheral wall of the bottom of the body.

[0019] Furthermore, the opening position and the mixed fluid outlet position are at the same horizontal position.

[0020] Furthermore, the plunger pump is connected to a gas production pipeline, and the gas production pipeline is arranged at a ground wellhead.

[0021] Furthermore, the plunger pump is connected to the oil pipe through a gas production line.

[0022] Furthermore, the gas production pipeline is provided with a plurality of valves and a plurality of instruments.

[0023] Another object of the present invention is achieved by the following technical solutions:

[0024] A method for drainage using a fixed pipe column jet pump, comprising:

[0025] The plunger pump injects the power fluid into the oil pipe;

[0026] The power fluid is transported through the oil pipe to a jet pump installed at one end of the oil pipe at the bottom of the well;

[0027] The power fluid is injected by the jet pump to generate negative pressure to suck the bottom hole fluid, and mix with the sucked bottom hole fluid to form a mixed liquid. The mixed liquid is lifted from the opening to the ground after pressure increase.

[0028] Furthermore, the mixed liquid enters the annulus between the oil pipe and the casing through the opening through the pressurized liquid and is lifted to the surface.

[0029] Beneficial effects of the present invention:

[0030] The present invention provides a fixed tubing jet pump production system and method. By installing the jet pump provided by the present invention on the oil pipe, the full-diameter integrity of the wellbore is strong, and the investment is small, the management and maintenance cost is low, and the equipment utilization rate is high. Secondly, when the jet pump is installed in the present invention, there is no need to move the underground production oil pipe of the original gas well, and the oil pipe is opened through low-cost rope operation measures, which greatly reduces the cost of conventional measures for well pressure and oil pipe lifting, and the jet pump is installed in the oil pipe through low-cost rope operation measures.

[0031] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A framework diagram of a jet pump, oil pipe and casing in a fixed-pipe jet pump drainage system according to an embodiment of the present invention is shown;

[0034] Figure 2 It shows a schematic structural diagram of a fluid inlet and a mixed fluid outlet in a jet pump according to an embodiment of the present invention;

[0035] Figure 3 A flow chart of a method for drainage by a fixed pipe column jet pump according to an embodiment of the present invention is shown;

[0036] In the figure:

[0037] 1. Casing; 2. Oil pipe; 3. Body; 4. Well fluid inlet; 5. First sealing element; 6. Mixed fluid outlet; 7. Opening; 8. Second sealing element; 9. Slip; 10. Second inlet chamber; 11. Diffuser chamber; 12. Negative pressure chamber; 13. Nozzle; 14. First inlet chamber. DETAILED DESCRIPTION

[0038] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] The embodiment of the present invention provides a fixed pipe column jet pump drainage system, comprising: a plunger pump, an oil pipe 2 connected to the plunger pump, a casing 1 and a jet pump arranged outside the oil pipe 2, such as Figure 1 As shown;

[0040] The jet pump is installed at one end of the oil pipe 2 at the bottom of the well, and the oil pipe 2 is provided with a plurality of openings 7 near the installation location of the jet pump;

[0041] The plunger pump is used to inject the power fluid into the oil pipe 2;

[0042] The oil pipe 2 is used to transport the power fluid to the jet pump;

[0043] The jet pump is used to inject power fluid to generate negative pressure to suck bottom hole fluid, and to lift the mixed fluid; wherein the mixed fluid includes power fluid and bottom layer fluid.

[0044] In the embodiment of the present invention, the jet pump comprises a body 3;

[0045] The body 3 is a cavity structure, and the cavity structure of the body 3 is divided into a first inlet cavity 14, a negative pressure cavity 12, a pressure diffusion cavity 11 and a second inlet cavity 10 from top to bottom, and the negative pressure cavity 12 is connected to the pressure diffusion cavity 11;

[0046] A nozzle 13 is provided at the connection between the first inlet chamber 14 and the negative pressure chamber 12, and the nozzle 13 is used to spray high-pressure power fluid to form a negative pressure in the negative pressure chamber 12 of the jet pump so as to suck the bottom hole fluid;

[0047] The body 3 is provided with a well fluid inlet 4 on the annular wall of the negative pressure chamber 12. Figure 2As shown, the well fluid inlet 4 connects the negative pressure chamber 12 and the second inlet chamber 10. The arrangement of the well fluid inlet 4 facilitates the bottom hole fluid to enter the negative pressure chamber 12 through the second inlet chamber 10 under the action of the sinking pressure.

[0048] The main body 3 is provided with a mixed fluid outlet 6 on the annular wall of the diffusion chamber 11. Figure 2 As shown, the mixed fluid outlet 6 is arranged to facilitate the mixed fluid (the high-pressure power fluid sprayed by the nozzle 13 and the bottom hole fluid entering the negative pressure chamber 12, entering the pressure diffusion chamber 11 and being mixed in the pressure diffusion chamber 11) to be discharged from the body 3 of the jet pump through the pressure-increasing pressure diffusion chamber 11, and then enter the annulus between the oil pipe 2 and the casing 1 through the opening 7 and be lifted to the ground;

[0049] The bottom hole fluid passes through the second inlet chamber 10, the well fluid inlet 4, and the negative pressure chamber 12 in sequence to reach the diffusion chamber 11 as the first fluid path. The high-pressure power fluid passes through the first inlet chamber 14, the nozzle 13, and the negative pressure chamber 12 in sequence to reach the diffusion chamber 11 as the second fluid path. The first fluid path and the second fluid path are two completely independent paths and do not interfere with or affect each other.

[0050] In some embodiments, the opening 7 on the oil pipe 2 can be completed by low-cost rope operation after determining a reasonable installation position of the jet pump.

[0051] In some embodiments, to ensure that the mixed liquid can only flow to the opening 7, the main body 3 is provided with a first seal 5 and a second seal 8 on both sides of the mixed fluid outlet 6, and when the jet pump is installed at one end of the oil pipe 2 at the bottom of the well, first ensure that the opening 7 of the oil pipe 2 is located between the first seal 5 and the second seal 8, and then make the position of the opening 7 and the position of the mixed fluid outlet 6 at the same horizontal position, so that the two are aligned. Specifically, the first seal 5 and the second seal 8 can be rubber sealing rings.

[0052] In some embodiments, to prevent the jet pump from moving downward under the action of high-pressure power fluid, a slip 9 is provided on the bottom peripheral wall of the main body 3. When the jet pump is installed at one end of the oil pipe 2 at the bottom of the well, the slip 9 is used to anchor the oil pipe 2 to fix the relative position of the oil pipe 2 and the jet pump.

[0053] In some embodiments, the plunger pump is connected to a gas production pipeline, the gas production pipeline is arranged at a wellhead on the ground, the plunger pump is connected to the oil pipe 2 through the gas production pipeline, and the gas production pipeline is provided with a plurality of valves and a plurality of instruments;

[0054] The gas production pipeline includes multiple pipelines. The combination of the gas production pipeline, multiple valves and multiple instruments can facilitate the separation of mixed liquid, the separation of liquid and gas, the discharge of oil products, the discharge of gas products, and the recycling of the obtained separated liquid (the separated liquid can be regenerated into high-pressure power liquid through a plunger pump).

[0055] like Figure 3 As shown, an embodiment of the present invention provides a method for drainage using a fixed pipe column jet pump, comprising:

[0056] The plunger pump injects the power fluid into the oil pipe 2;

[0057] The power fluid is transported through the oil pipe 2 to a jet pump installed at one end of the oil pipe 2 at the bottom of the well;

[0058] The power fluid is injected by the jet pump to generate negative pressure to suck the bottom hole fluid, and mixes with the sucked bottom hole fluid to form a mixed liquid. The mixed liquid is lifted to the ground from the opening 7 after pressure increase.

[0059] Specifically, the plunger pump injects the power fluid into the oil pipe 2, and the power fluid is pressurized by the plunger pump to become high-pressure power fluid;

[0060] The high-pressure power fluid is transported through the oil pipe 2 and passes through the first inlet chamber 14 to enter the jet pump. The high-pressure power fluid forms a negative pressure in the negative pressure chamber 12 through the jet. Under the action of the negative pressure, the bottom hole fluid passes through the second inlet chamber 10 and the well fluid inlet 4 in turn to enter the negative pressure chamber 12, and then enters the diffusion chamber 11 to mix with the high-pressure power fluid entering the diffusion chamber 11 to form a mixed liquid.

[0061] The mixed liquid is pressurized in the diffusion chamber 11 and passes through the mixed fluid outlet 6, enters the annulus between the oil pipe 2 and the casing 1 from the opening 7, and is lifted to the surface.

[0062] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A fixed pipe column jet pump drainage system, comprising a plunger pump, an oil pipe (2) connected to the plunger pump, and a casing (1) sleeved outside the oil pipe (2), characterized in that: Also includes a sitting jet pump; The jet pump is installed at one end of the oil pipe (2) at the bottom of the well, and the oil pipe (2) is provided with a plurality of openings (7) near the installation location of the jet pump; The plunger pump is used to inject power fluid into the oil pipe (2); The oil pipe (2) is used to transport power fluid to the jet pump; The jet pump is used for jetting power fluid to generate negative pressure to suck bottom hole fluid, and for lifting the mixed fluid.

2. The fixed pipe column jet pump drainage system according to claim 1 is characterized in that: The jet pump comprises a body (3); The body (3) is a cavity structure, and the cavity of the body (3) is divided into a first inlet cavity (14), a negative pressure cavity (12), a pressure diffusion cavity (11), and a second inlet cavity (10) from top to bottom, and the negative pressure cavity (12) is connected to the pressure diffusion cavity (11); A nozzle (13) is provided at the connection point between the first inlet chamber (14) and the negative pressure chamber (12); The body (3) is provided with a well fluid inlet (4) on the annular wall of the negative pressure chamber (12), and the well fluid inlet (4) communicates with the negative pressure chamber (12) and the second inlet chamber (10); The main body (3) is provided with a mixed fluid outlet (6) on the annular wall of the diffusion chamber (11).

3. The fixed pipe column jet pump drainage system according to claim 2, characterized in that: The body (3) is provided with a first sealing member (5) and a second sealing member (8) on both sides of the mixed fluid outlet (6).

4. The fixed pipe column jet pump drainage system according to claim 3 is characterized in that: A slip (9) is provided on the outer peripheral wall of the bottom of the body (3).

5. The fixed pipe column jet pump drainage system according to claim 4, characterized in that: The position of the opening (7) is at the same horizontal position as the position of the mixed fluid outlet (6).

6. A fixed pipe column jet pump drainage system according to any one of claims 1 to 5, characterized in that: The plunger pump is connected to a gas production pipeline, and the gas production pipeline is arranged at a ground wellhead.

7. The fixed pipe column jet pump drainage system according to claim 6, characterized in that: The plunger pump is connected to the oil pipe (2) through a gas production line.

8. The fixed pipe column jet pump drainage system according to claim 6, characterized in that: The gas production pipeline is provided with a plurality of valves and a plurality of instruments.

9. A method for drainage using a fixed pipe column jet pump, characterized in that: include: The plunger pump injects the power fluid into the oil pipe (2); The power fluid is transported through the oil pipe (2) to a jet pump which is installed at one end of the oil pipe (2) at the bottom of the well. The power fluid is ejected by the jet pump to generate negative pressure to suck the bottom hole fluid and mix with the sucked bottom hole fluid to form a mixed liquid. The mixed liquid is lifted from the opening (7) to the ground after being pressurized.

10. A method for drainage using a fixed pipe column jet pump according to claim 9, characterized in that: The mixed liquid is pressurized and enters the annulus between the oil pipe (2) and the casing (1) from the opening (7) and is lifted to the surface.

Images