Multi-stage reinjection controllable same-well double-pump injection-production tool and injection-production process method thereof

Abstract

The invention relates to the technical field of same-well injection and production, in particular to a multi-stage reinjection controllable same-well double-pump injection and production tool and an injection and production process method thereof, a water injection pump and an oil production pump are adopted for operation, oil production operation and water injection operation can be conducted at the same time, a switch can be controlled separately, control is more flexible, and operation is more convenient. The oil taking pipeline, the water taking pipeline and the reinjection pipeline are matched with injection and production of the same well, and the capillary tubes are used for controlling the water distributors of different water injection layers, so that a single water distributor switch can be turned on to inject water into a single-stage water injection layer, or a plurality of water distributor switches can be turned on to inject water into multiple stages of water injection layers, accurate dynamic adjustment of reinjection is achieved, and the water injection efficiency is improved. And therefore, the development of the same-well single-pump injection-production process is adapted and promoted.

Description

Technical Field

[0001] The present invention relates to the technical field of co - well injection and production, and particularly to a multi - stage reinjection controllable co - well dual - pump injection and production tool and its injection and production process method. Background Art

[0002] At present, the oilfield water injection plan requires that the reinjection layer should meet three to five sections, and each section should be separated by a packer. In co - well injection and production, packers are used to separate multiple reinjection layers underground. Limited by the current injection and production string tools, reinjection can only be carried out simultaneously to multiple reinjection layers. Since the reinjection layer is composed of multiple oil layers and there are large differences in inter - layer permeability, that is, each oil layer has different water absorption capacities at the same injection pressure, this results in the reinjection layer only being able to inject water generally. To carry out layered water injection according to the requirements of the oilfield water injection plan, the requirement of multi - stage fine water injection pursued by oilfield development cannot be achieved. This has caused the proportion of water - absorbing thickness of oil layers with different properties to be unable to increase, seriously affecting the swept volume of the injected water. Therefore, it is necessary to develop a tool and process that can implement pressure - dividing and layered water injection. Summary of the Invention

[0003] The purpose of the present invention is to provide a multi - stage reinjection controllable co - well dual - pump injection and production tool and its injection and production process method for the defects existing in the prior art. By connecting the injection pump and the production pump to the corresponding pipelines respectively, it can implement simultaneous injection and production operations or separate - control injection and production operations. At the same time, capillary tubes of multiple water distributors for controlling different water injection layers are used to realize the regulation of injecting water into a single - stage water injection layer by opening the switch of a single water distributor or injecting water into a multi - stage water injection layer by opening the switches of multiple water distributors, so as to achieve precise dynamic adjustment of reinjection.

[0004] The technical solution of the present invention is: a multi - stage reinjection controllable co - well dual - pump injection and production tool, including a dual - pump injection and production mechanism and an integrated packer and water distribution pipe string connected longitudinally in multiple stages; The integrated packer and water distribution pipe string includes a tubing, a water pipe and a tool pipe arranged from inside to outside. An annular upper - water channel is formed between the tubing and the water pipe, and an annular water injection channel is formed between the water pipe and the tool pipe. A group of capillary tubes arranged in a circumferential manner are provided in the water injection channel; The tool pipe includes an upper joint, a packer and a water distributor connected in sequence from top to bottom. The pressure - transmitting setting hole of the packer is communicated with the water injection channel. The water distributor includes a cylindrical main body. A valve cavity and an outer diversion hole communicating the valve cavity with the water injection channel are opened on the cylindrical wall of the cylindrical main body. A valve sleeve is connected to the bottom of the valve cavity. An inner diversion hole communicating with the outer diversion hole is opened on the valve sleeve. A valve core that is slidably and sealingly connected with the inner diversion hole is arranged in the valve sleeve. After the upper end of the valve core extends out of the valve sleeve, a piston head that is slidably and sealingly connected with the valve cavity is provided; A set of liquid inlet channels corresponding to the inlet ends of the capillary tubes one by one are formed on the upper joint. The outlet end of one of the capillary tubes communicates with the top of the valve cavity, and the outlet ends of the remaining capillary tubes communicate with a set of liquid outlet channels formed on the cylindrical body one by one; The multi-stage integrated packer water distribution pipe string is connected from top to bottom to form a tool string. The adjacent upper and lower oil pipes are connected to form an oil extraction pipeline, the adjacent upper and lower water pipes are connected to form a water extraction pipeline, and the adjacent upper and lower water injection channels are connected to form a reinjection pipeline; The double-pump injection and production mechanism includes an injection water pump and a production oil pump. The inlet end of the production oil pump communicates with the oil extraction pipeline, and an oil extraction valve is installed on the oil extraction pipeline. The outlet end of the production oil pump is connected to the production pipeline pumped out of the ground through a pipeline, and a production valve is installed on the production pipeline; The inlet end of the injection water pump communicates with the water extraction pipeline, and a water extraction valve is installed on the water extraction pipeline. The outlet end of the injection water pump is connected to the reinjection pipeline pumped into the well through a pipeline, and a reinjection valve is installed on the reinjection pipeline; A pressure transmission branch extending to the ground is also connected to the reinjection pipeline, and a pressure detection module is connected through the pressure transmission branch.

[0005] Preferably, a pressure transmission hole is also formed on the barrel wall of the cylindrical body, and the pressure transmission hole communicates the annular space between the valve core and the valve cavity with the water injection channel.

[0006] Preferably, the bottom of the valve core is in a conical structure, and a conical surface for cooperating with and limiting the bottom of the valve core is provided at the bottom of the inner cavity of the valve sleeve.

[0007] For the multi-stage reinjection controllable co-well double-pump injection and production process method, the above multi-stage reinjection controllable co-well double-pump injection and production tool is adopted; The co-well double-pump injection and production process method includes the following steps: First, the multi-stage integrated packer water distribution pipe string is connected from top to bottom to form a tool string. The adjacent upper and lower oil pipes are connected to form an oil extraction pipeline, the adjacent upper and lower water pipes are connected to form a water extraction pipeline, and the adjacent upper and lower water injection channels are connected to form a reinjection pipeline; Among a set of capillary tubes of the integrated packer water distribution pipe string located above, only one is connected to the valve cavity for switching the water distributor, and the bottoms of the remaining capillary tubes are connected to the tops of the capillary tubes of the integrated packer water distribution pipe string located below. Connecting downward in this way forms a capillary string for driving the switching of different water distributors; Then, the tool string and the double-pump injection and production mechanism are lowered into the injection and production well; During the packer setting operation: open the water extraction valve and the reinjection valve, pump the well water into the reinjection pipeline through the water extraction pipeline, the injection water pump and the reinjection pipeline. At this time, all the water distributors are in the closed state, and the hydraulic pressure drives the setting of each stage of the packer through each pressure transmission setting hole, forming multiple vertically arranged water injection layers, and a water distributor is equipped at each water injection layer; During oil production operations: Open the oil extraction valve and the production valve, and pump the oil through the oil extraction pipeline, the oil pump, and the production pipeline to the ground. During water injection operations: Open the water intake valve and the reinjection valve, pump the well water into the water injection layer through the water intake pipeline, the water injection pump, and the reinjection pipeline. During the water injection process, the water injection pressure is detected in real-time by the pressure detection module, and according to the change of the water injection pressure, the single water distributor switch is opened to inject water into the single-stage water injection layer by injecting pressure into different capillaries, or multiple water distributor switches are opened to adjust the position and injection volume of the reinjected water for the multi-stage water injection layer.

[0008] Preferably, a ground controller and a hydraulic pump are also used in the same-well injection-production process method. Establish an electrical connection between the ground controller, the hydraulic pump, and the pressure detection module, and control the opening and closing of the oil extraction valve, the water intake valve, the production valve, and the reinjection valve through the ground controller. The hydraulic outlet of the hydraulic pump is respectively connected to the capillary string controlling each water distributor through a pressure injection pipeline, and a pressure control valve is provided on each pressure injection pipeline entering the water distributor. Both the pressure control valve and the hydraulic pump are electrically connected to the ground controller.

[0009] Compared with the prior art, the present invention has the following advantages: The present invention uses a water injection pump and an oil pump for operations. The oil production operation and the water injection operation can be carried out simultaneously or can be controlled separately, and the control is more flexible.

[0010] In addition, the present invention has an oil extraction pipeline, a water intake pipeline, a reinjection pipeline adapted to the same-well injection-production, and multiple capillaries for controlling water distributors in different water injection layers, so that the single water distributor switch can be opened to inject water into the single-stage water injection layer, or multiple water distributor switches can be opened to inject water into the multi-stage water injection layer, realizing precise dynamic adjustment of reinjection, thus adapting to and promoting the process development of the same-well single-pump injection-production. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a schematic diagram of the upper structure of an integrated packer water distribution pipe string; Figure 2 It is a schematic diagram of the lower structure of an integrated packer water distribution pipe string; Figure 3 It is a schematic diagram of the process flow of a multi-stage reinjection controllable same-well double-pump injection-production; In the figure: 1. tubing, 2. water pipe, 3. upper joint, 4. packer, 5. water distributor, 6. cylindrical main body, 7. piston head, 8. valve core, 9. valve sleeve, 10. upper water channel, 11. injection channel, 12. capillary tube, 13. pressure transmission setting hole, 14. pressure transmission hole, 15. outer diversion hole, 16. inner diversion hole, 17. production pipeline, 18. pressure detection module, 19. production valve, 20. reinjection pipeline, 21. reinjection valve, 22. injection pump, 23. water intake valve, 24. oil production valve, 25. oil production pipeline, 26. water intake pipeline, 27. pressure control valve, 28. hydraulic pump, 29. ground controller, 30. pressure boosting pipeline, 31. oil production pump. Specific embodiments

[0012] The following further describes the present invention in conjunction with the drawings and embodiments. Embodiment 1

[0013] The multi-stage reinjection controllable co-well dual-pump injection and production tool includes a dual-pump injection and production mechanism and an integrated packer and water distribution pipe string connected longitudinally in multiple stages.

[0014] Among them, the integrated packer and water distribution pipe string includes a tubing 1, a water pipe 2 and a tool pipe arranged from inside to outside. An upper water channel 10 is formed in the annulus between the tubing 1 and the water pipe 2, and an injection channel 11 is formed in the annulus between the water pipe 2 and the tool pipe. A group of capillary tubes 12 arranged in a surrounding manner are provided in the injection channel 11.

[0015] The tool pipe includes an upper joint 3, a packer 4 and a water distributor 5 connected in sequence from top to bottom. The pressure transmission setting hole 13 of the packer 4 is communicated with the injection channel 11. The water distributor 5 includes a cylindrical main body 6. A valve cavity and an outer diversion hole 15 communicating the valve cavity with the injection channel 11 are formed in the cylindrical wall of the cylindrical main body 6. A valve sleeve 9 is connected to the bottom of the valve cavity. An inner diversion hole 16 communicating with the outer diversion hole 15 is formed in the valve sleeve 9. A valve core 8 cooperating with the inner diversion hole 16 is slidably and sealingly connected in the valve sleeve 9. A piston head 7 slidably and sealingly connected to the valve cavity is provided at the upper end of the valve core 8 after the valve core 8 extends out of the valve sleeve 9.

[0016] A group of liquid inlet channels corresponding to the inlet ends of the capillary tubes 12 one by one are formed in the upper joint 3. The outlet end of one of the capillary tubes 12 is communicated with the top of the valve cavity, and the outlet ends of the remaining capillary tubes 12 are communicated with a group of liquid outlet channels formed in the cylindrical main body 6 one by one.

[0017] The multi-stage integrated packer and water distribution pipe string are connected from top to bottom to form a tool pipe string. The adjacent tubing 1s above and below are connected into an oil production pipeline 25, the adjacent water pipes 2 above and below are connected into a water intake pipeline 26, and the adjacent injection channels 11 above and below are connected into a reinjection pipeline 20.

[0018] The double-pump injection and production mechanism includes an injection water pump 22 and a production oil pump 31. The inlet end of the production oil pump 31 is connected to the oil extraction pipeline 25, and an oil extraction valve 24 is installed on the oil extraction pipeline 25. The outlet end of the production oil pump 31 is connected to the production pipeline 17 that pumps out to the ground through a pipeline, and a production valve 19 is installed on the production pipeline 17.

[0019] The inlet end of the injection water pump 22 is connected to the water intake pipeline 26, and a water intake valve 23 is installed on the water intake pipeline 26. The outlet end of the injection water pump 22 is connected to the reinjection pipeline 20 that pumps into the well through a pipeline, and a reinjection valve 21 is installed on the reinjection pipeline 20.

[0020] There is also a pressure transmission branch extending to the ground connected to the reinjection pipeline 20, and it is connected to the pressure detection module 18 through the pressure transmission branch.

[0021] Working principle: Operation of the switching water distributor 5: When closing the water distributor 5, hydraulic pressure is pumped into the capillary 12 connected to the valve cavity. The hydraulic pressure enters the valve cavity through the capillary 12 to drive the piston head 7 to drive the valve core 8 to move downward, thereby blocking the internal diversion hole 16. When opening the water distributor 5, just disconnect the hydraulic pressure pumped into the above-mentioned capillary 12, and the downhole pressure can push the valve core 8 and the piston head 7 to move upward through the valve sleeve 9, thereby opening the internal diversion hole 16.

[0022] When setting the packer: Hydraulic pressure enters the packer 4 through the water injection channel 11 and the pressure transmission setting hole 13, thereby driving the packer 4 to set. Embodiment 2

[0023] This embodiment is further optimized on the basis of the above embodiment. Specifically: Such as Figure 2 , a pressure transmission hole 14 is also opened on the barrel wall of the cylindrical main body 6. The pressure transmission hole 14 connects the annular space between the valve core 8 and the valve cavity with the water injection channel 11; In this design, during the water injection operation, the hydraulic pressure in the water injection channel 11 enters the annular space between the valve core 8 and the valve cavity through the pressure transmission hole 14, so as to be able to drive the piston head 7 to drive the valve core 8 to move upward to open the water injection channel 11 of the water distributor 5. Through this design, the stability and smoothness of opening the water distributor 5 are further improved.

[0024] The bottom of the valve core 8 is in a conical structure, and the bottom of the inner cavity of the valve sleeve 9 is provided with a conical surface that cooperates with and limits the bottom of the valve core 8. With this design, when the bottom of the valve core 8 contacts the conical surface, a certain gap is left between the lower end surface of the piston head 7 and the upper end surface of the valve sleeve 9, and the pressure transmission hole 14 is located in this gap, so as to be able to guide the injection liquid into this gap to drive the piston head 7 to move upward when opening the water distributor 5. Embodiment 3

[0025] As Figures 1 to 3 , the injection and production process method of this embodiment adopts the injection and production tool of the above-mentioned multi-stage reinjection controllable same-well double pumps, including the following steps: First, connect the multi-stage integrated packer water distribution pipe string from top to bottom to form a tool string. The adjacent upper and lower tubing 1s are connected into an oil extraction pipeline 25, the adjacent upper and lower water pipes 2 are connected into a water extraction pipeline 26, and the adjacent upper and lower water injection channels 11 are connected into a reinjection pipeline 20.

[0026] Only one of a group of capillary tubes 12 of the integrated packer water distribution pipe string located above is connected to the valve cavity for switching the water distributor 5, and the bottoms of the remaining capillary tubes 12 are connected to the tops of the capillary tubes 12 of the integrated packer water distribution pipe string located below, and are connected downward in this way to form a string of capillary tubes 12 for driving the switching of different water distributors 5.

[0027] Then, lower the tool string and the double-pump injection and production mechanism into the injection and production well.

[0028] During the setting operation of the packer 4: Open the water extraction valve 23 and the reinjection valve 21, pump the well water into the reinjection pipeline 20 through the water extraction pipeline 26, the injection pump 22 and the reinjection pipeline 20. At this time, all the water distributors 5 are in the closed state, and the hydraulic pressure drives each stage of the packer 4 to set through each pressure transmission setting hole 13, forming multiple injection layers arranged vertically, and a water distributor 5 is equipped at each injection layer.

[0029] During the oil production operation: Open the oil extraction valve 24 and the production valve 19, and pump the oil to the ground through the oil extraction pipeline 25, the oil production pump 31 and the production pipeline 17.

[0030] During the water injection operation: Open the water extraction valve 23 and the reinjection valve 21, pump the well water into the injection layer through the water extraction pipeline 26, the injection pump 22 and the reinjection pipeline 20. During the water injection process, the water injection pressure is detected in real time by the pressure detection module 18, and according to the change of the water injection pressure, the single water distributor 5 is opened by injecting pressure into different capillary tubes 12 to inject water into the single-stage injection layer, or multiple water distributors 5 are opened to adjust the position and injection volume of the reinjected water for the multi-stage injection layer.

[0031] This embodiment uses the injection pump 22 and the oil production pump 31 for operation. The oil production operation and the water injection operation can be carried out simultaneously or can be controlled separately, and the control is more flexible. In addition, as a preferred mode of this embodiment: A ground controller 29 and a hydraulic pump 28 are also used.

[0032] Among them, there is a ground controller 29, which can be a PLC controller, an industrial control computer, etc. The ground controller 29 receives the data collected by the pressure detection module 18. The hydraulic outlet of the hydraulic pump 28 and each water distributor 5 are respectively connected through a pressure boosting pipeline 30. By controlling the opening of different pressure control valves 27 through the ground controller 29, the water distributor 5 of different injection layers can be opened to carry out water injection operations on them.

[0033] In addition, chemical treatment can also be carried out on a certain injection layer by pumping chemical agents through the pressure transmission branch of the pressure detection module 18. For example, a plugging removal agent can be pumped into the blocked injection layer through the pressure transmission branch for treatment.

[0034] The present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the purpose of the present invention, and the changed content still belongs to the protection scope of the present invention.

Claims

1. A multi-stage reinjection controllable co-well dual-pump injection-production tool, characterized in that: It includes a double-pump injection and production mechanism and an integrated packer and water distribution pipe string connected longitudinally in multiple stages; The integrated packer and water distribution pipe string includes an oil pipe, a water pipe, and a tool pipe arranged from the inside to the outside. An annular upper water channel is formed between the oil pipe and the water pipe, and an annular water injection channel is formed between the water pipe and the tool pipe. A group of capillary tubes arranged in a surrounding manner is provided in the water injection channel; The tool pipe includes an upper joint, a packer, and a water distributor connected in sequence from top to bottom. The pressure transmission and setting hole of the packer is communicated with the water injection channel. The water distributor includes a cylindrical main body. A valve cavity and an outer diversion hole communicating the valve cavity with the water injection channel are opened on the cylindrical wall of the cylindrical main body. A valve sleeve is connected to the inner bottom of the valve cavity. An inner diversion hole communicating with the outer diversion hole is opened on the valve sleeve. A valve core cooperating with the inner diversion hole is slidably and sealingly connected in the valve sleeve. After the upper end of the valve core extends out of the valve sleeve, a piston head slidably and sealingly connected to the valve cavity is provided; A group of liquid inlet flow channels corresponding to the inlet ends of the capillary tubes one by one are opened on the upper joint. The outlet end of one of the capillary tubes is communicated with the top of the valve cavity, and the outlet ends of the remaining capillary tubes are communicated with a group of liquid outlet flow channels opened on the cylindrical main body one by one; The multi-stage integrated packer and water distribution pipe string are connected from top to bottom to form a tool pipe string. The adjacent oil pipes up and down are connected into an oil extraction pipeline, the adjacent water pipes up and down are connected into a water extraction pipeline, and the adjacent water injection channels up and down are connected into a reinjection pipeline; The double-pump injection and production mechanism includes an injection pump and a production pump. The inlet end of the production pump is communicated with the oil extraction pipeline, and an oil extraction valve is installed on the oil extraction pipeline. The outlet end of the production pump is connected to the production pipeline pumped out of the ground through a pipeline, and a production valve is installed on the production pipeline; The inlet end of the injection pump is communicated with the water extraction pipeline, and a water extraction valve is installed on the water extraction pipeline. The outlet end of the injection pump is connected to the reinjection pipeline pumped into the well through a pipeline, and a reinjection valve is installed on the reinjection pipeline; A pressure transmission branch extending to the ground is also connected to the reinjection pipeline, and a pressure detection module is connected through the pressure transmission branch; 2. The integrated packer water distribution pipe string according to claim 1, characterized in that: A pressure transmission hole is also opened on the cylindrical wall of the cylindrical main body. The pressure transmission hole communicates the annular gap between the valve core and the valve cavity with the water injection channel; 3. The integrated packer and water distribution string according to claim 2, wherein: The bottom of the valve core is in a conical structure, and a conical surface portion cooperating with the bottom of the valve core for limiting is provided at the inner bottom of the valve sleeve cavity; 4. A multi-stage reinjection controllable same-well dual-pump injection-production process method, characterized in that: Adopt the multi-stage reinjection controllable co-well double-pump injection and production tool described in any one of claims 1 to 3; The co-well double-pump injection and production process method Includes the following steps: First, connect the multi-stage integrated packer and water distribution pipe string from top to bottom to form a tool pipe string. The adjacent oil pipes up and down are connected into an oil extraction pipeline, the adjacent water pipes up and down are connected into a water extraction pipeline, and the adjacent water injection channels up and down are connected into a reinjection pipeline; Only one of a group of capillary tubes of the integrated packer and water distribution pipe string located above is communicated with the valve cavity for switching the water distributor, and the bottoms of the remaining capillary tubes are connected to the tops of the capillary tubes of the integrated packer and water distribution pipe string located below. Connect downward in this way to form a capillary string for driving the switching of different water distributors; Then, lower the tool pipe string and the double-pump injection and production mechanism into the injection and production well; During the packer setting operation: Open the water intake valve and the reinjection valve, pump the well water into the reinjection pipeline through the water intake pipeline, the injection pump, and the reinjection pipeline. At this time, all the water distributors are in the closed state, and the hydraulic pressure drives each stage of the packer to set through each pressure transmission setting hole, forming multiple injection layers arranged vertically and horizontally, and a water distributor is equipped at each injection layer; During the oil production operation: Open the oil intake valve and the production valve, and pump the oil to the ground through the oil intake pipeline, the oil production pump, and the production pipeline; During the water injection operation: Open the water intake valve and the reinjection valve, pump the well water into the injection layer through the water intake pipeline, the injection pump, and the reinjection pipeline. During the water injection process, the water injection pressure is detected in real time through the pressure detection module, and according to the change of the water injection pressure, the single water distributor switch is opened to inject water into the single-stage injection layer by injecting pressure into different capillaries, or multiple water distributor switches are opened to adjust the position and water injection volume of the reinjected water to the multi-stage injection layer.

5. The multi-stage re-injection controllable same-well double-pump injection and production process method according to claim 4, characterized in that: A ground controller and a hydraulic pump are also used in the same-well injection-production process method; The ground controller is electrically connected to the hydraulic pump and the pressure detection module, and the opening and closing of the oil intake valve, the water intake valve, the production valve, and the reinjection valve are controlled through the ground controller; The hydraulic outlet of the hydraulic pump is respectively connected to the capillary string controlling each water distributor through a pressure injection pipeline, and a pressure control valve is provided on each pressure injection pipeline entering the water distributor. The pressure control valve and the hydraulic pump are both electrically connected to the ground controller.

Images