On-site operation device for increasing yield and improving oil and gas recovery ratio through ultrasonic physics-chemistry cooperation and working method

Abstract

The invention relates to an on-site operation device for increasing the yield and improving the oil and gas recovery ratio through ultrasonic physics-chemistry cooperation and a working method, and belongs to the technical field of oil and gas exploitation. The device comprises a ground work station, a cable, a pipe column, a chemical augmented injection device and an ultrasonic vibration system, the pipe column is arranged in a shaft, the ground work station and the chemical augmented injection device are both connected with the cable, the cable penetrates through the pipe column to be arranged in the shaft, and the ultrasonic vibration system is arranged at the tail end of the cable. The ultrasonic wave and the chemical reagent are combined, the ultrasonic physical-chemical synergistic yield increasing technology is adopted, the permeation efficiency and the reaction rate of the chemical reagent are remarkably improved through the cavitation effect and the high-temperature and high-pressure effect of the ultrasonic wave, the higher yield increasing effect is achieved, and the effect in oil and gas exploitation is far better than the effect generated by independently using one technology.

Description

Technical Field

[0001] The invention relates to a field operation device and a working method for ultrasonic physical-chemical synergistic production increase and oil and gas recovery rate, belonging to the technical field of oil and gas exploitation. Background Art

[0002] Energy is the cornerstone of national economic development. Together with water and food, it is one of the three major elements that humans rely on for survival. Fossil energy such as coal, oil and natural gas accounts for more than 80% of my country's energy consumption. my country's dependence on foreign oil and natural gas is very high, with an oil dependence of more than 70% and a natural gas dependence of more than 45%, which seriously threatens my country's energy security. Increasing reserves and production is one of the most effective ways.

[0003] After primary and secondary exploitation of oil and natural gas, there is still a large amount of residual oil and gas stored in underground reservoirs, which needs to be exploited by tertiary exploitation to improve oil and gas recovery. At present, the main tertiary exploitation technologies include CO2 flooding and acidification. These technologies are highly destructive to reservoirs, high in cost, and have a large amount of tail waste emissions, which seriously hinders the green and high-quality development of oil fields.

[0004] Ultrasonic technology is a physical mining technology with simple operation, wide application range, green and environmental protection, no pollution to reservoirs, low operating cost and significant effect. The working principle of ultrasonic waves is mainly to utilize the cavitation effect of ultrasonic waves. When ultrasonic waves propagate in the medium, they will produce periodic positive and negative pressures. Negative pressure will make the distance between the media sparse, and positive pressure will make the media focus on each other. When the sound intensity of ultrasonic waves is large enough, the negative pressure exceeds the local tensile strength of the liquid medium and bubbles will be generated. Under the action of positive pressure, the bubble radius will shrink, and under the action of negative pressure, the bubble radius will increase. Under this periodic pressure, when the radius of the bubble expands to a certain extent, an explosion will occur. The explosion will produce high temperature and high pressure (5000K, 2000atm), shock waves and microjets. This effect can remove wax and unblock the downhole perforation section on the one hand; it can create cracks in the reservoir and improve the physical properties of the reservoir; on the other hand, it can promote chemical reactions and increase the reaction rate. Thereby improving the recovery rate of oil and gas wells.

[0005] Therefore, ultrasonic technology can not only remove wax, unblock and reduce viscosity, but also cause reservoir fracture and temperature increase, promote the desorption of coalbed methane and shale gas, and is a green way to extract oil and gas.

[0006] At present, most of the ultrasonic operations in China use single acoustic wave technology, which is mainly used for wax removal and plugging removal in old wells, but has poor effect on unconventional oil and gas reservoirs such as low-porosity and low-permeability reservoirs, heavy oil reservoirs and shale gas reservoirs. Therefore, the present invention is proposed. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention provides a field operation device for improving oil and gas recovery rate by combining ultrasonic physical-chemical synergistic production increase, which combines ultrasonic wave with chemical reagents and adopts ultrasonic physical-chemical synergistic production increase technology. Through the cavitation effect and high temperature and high pressure effect of ultrasonic wave, the penetration efficiency and reaction rate of chemical reagents are significantly improved, thereby achieving a higher production increase effect. The effect in oil and gas production is far better than the effect produced by using only one technology.

[0008] The present invention also provides a working method of the field operation device for increasing oil and gas recovery rate by synergistically increasing production with ultrasound physics and chemistry.

[0009] The technical solution of the present invention is as follows:

[0010] A field operation device for ultrasonic physical-chemical synergistic production increase to improve oil and gas recovery rate, comprising a ground workstation, a cable, a pipe string, a chemical injection device and an ultrasonic vibration system, wherein:

[0011] A pipe string is arranged in the wellbore, and the ground workstation and the chemical injection device are connected with the cable. The cable passes through the pipe string through a transmission component and is arranged in the wellbore. An ultrasonic vibration system is arranged at the end of the cable, and the transmission component is an existing pulley assembly.

[0012] Preferably according to the present invention, the ground workstation comprises a workbench, a control system, an ultrasonic generator and a display, the workbench is provided with a control system, the control system is connected with the ultrasonic generator, the display and the chemical injection device, and the ultrasonic generator is connected with a cable.

[0013] Preferably according to the present invention, the cable includes a wrapping layer, a signal line, a power line and a hollow tube, the wrapping layer is provided with the signal line, the power line and the hollow tube, the signal line is composed of 7 copper wires wound together, one end of the signal line is connected to an ultrasonic generator, and the other end is connected to an ultrasonic vibration system, the power line is connected to an ultrasonic vibration system, and one end of the hollow tube is connected to a chemical injection device.

[0014] According to a further preferred embodiment of the present invention, the wrapping layer is made of cross-linked polyethylene, and steel wires are uniformly doped in the cross-linked polyethylene to improve the overall strength.

[0015] Preferably, according to the present invention, the ultrasonic vibration system includes a shell, a circular tube, an adapter, a longitudinal vibration transducer and a tester. An adapter is provided at one end of the shell, a circular tube (i.e., a waveguide system) is provided in the middle of the shell, longitudinal vibration transducers are provided at both ends of the circular tube, two longitudinal vibration transducers are respectively connected to the adapter through leads, the adapter is connected to the signal line in the cable, and a tester is provided at the other end of the shell. The tester is used to test the bottom hole temperature, pressure and flow rate of the fluid, and corresponding sensors can be used for testing.

[0016] Preferably according to the present invention, the chemical injection device includes a liquid storage tank, a valve, a flow meter and a pressure pump. The liquid storage tank is connected to the pressure pump inlet through a pipeline. The connecting pipeline between the liquid storage tank and the pressure pump is provided with a valve and a flow meter. The pressure pump outlet is connected to a hollow tube with a cable through an injection pipeline.

[0017] The working method of the above-mentioned ultrasonic physical-chemical synergistic production increase and oil and gas recovery efficiency field operation device comprises the following steps:

[0018] (1) lowering the ultrasonic vibration system through the pipe string into the wellbore so that the ultrasonic vibration system is near the source formation;

[0019] (2) The ultrasonic generator generates a high-frequency electrical signal, which is transmitted to the longitudinal vibration transducer by a cable to generate ultrasonic waves. The longitudinal vibration of the ultrasonic waves is converted into radial vibrations through the circular tube. Both ends of the circular tube are excited by the longitudinal vibration transducers. When the length of the circular tube is an odd multiple of the half wavelength corresponding to the operation of the vibrator, the two longitudinal vibration transducers are excited in phase; when the length of the circular tube is an even multiple of the half wavelength corresponding to the operation of the vibrator, the two longitudinal vibration transducers are excited in anti-phase. The longitudinal vibration transducer operates at the longitudinal-diameter coupling resonance frequency of the circular tube, exciting the circular tube to generate longitudinal-diameter coupling vibrations, converting the input longitudinal vibrations into radial vibrations and radiating them into the surrounding strata. The tubular ultrasonic vibration system designed by the present invention radiates ultrasonic waves along the circular tube, and the radiation area is larger than that of ordinary sandwich transducers. At the same time, the radial vibration radiates sound energy to the surroundings, making the sound field more uniform.

[0020] (3) The valve is opened, the pressure pump is started, and the chemical agents stored in the liquid storage tank are injected into the wellbore through the cable and released in the target layer;

[0021] (4) After ultrasonic waves come into contact with the chemical agents in the wellbore, they vibrate at high frequencies and produce cavitation. On the one hand, they remove wax and unblock plugging in the perforated section and near-source formation in the wellbore, and produce cracks in the near-source formation. On the other hand, they combine with the injected chemical agents to promote the penetration of the chemical agents and increase the chemical reaction rate to achieve a better production increase effect. After ultrasonic physical-chemical transformation, the near-source formation is effectively dewaxed and unblocked, improving the flow conditions of oil and gas, and allowing the crude oil in the original formation to flow smoothly to the bottom of the well, thereby increasing the overall recovery rate.

[0022] Preferably, according to the present invention, during operation, if a high porosity and high permeability reservoir is encountered, only ultrasonic operation is used, and if a low porosity and low permeability reservoir and a heavy oil reservoir are encountered, a combination of ultrasonic operation and chemical agents is used.

[0023] During specific work, through the control system, the staff can monitor the downhole situation in real time, and optimize the operation effect by manually or automatically adjusting the power, frequency and action time of the ultrasonic operation. If the pressure and flow rate of the chemical injection device increase, the power and time of the ultrasonic operation will be automatically reduced; if the pressure and flow rate of the chemical injection device remain unchanged after increasing, the ultrasonic operation can be stopped; if the pressure and flow rate decrease, the power of the ultrasonic operation will be increased.

[0024] The beneficial effects of the present invention are:

[0025] 1. Economical and environmentally friendly, ultrasonic production increase belongs to physical field operation, which is green and environmentally friendly. The ultrasonic operation of the present invention has lower cost than other operation methods.

[0026] 2. The ultrasonic chemical operation of the present invention is simple to operate, flexible in operation mode, and short in operation time. After the ultrasonic operation tool is lowered, it is only necessary to adjust the parameters in the control system to perform the operation. At the same time, real-time adjustments are made according to the oil and gas type and reservoir characteristics. Each operation takes only a few hours and does not delay production.

[0027] 3. The effect is remarkable and lasts for a long time. After each operation, the recovery rate can be increased by 30%-50%, and the effect can last for more than 3-12 months. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the present invention;

[0029] Figure 2 It is a schematic diagram of the cable structure of the present invention;

[0030] Figure 3 It is a schematic diagram of the structure of the ultrasonic vibration system of the present invention;

[0031] Figure 4 It is a schematic diagram of the structure of the longitudinal vibration transducer of the present invention;

[0032] Figure 5 It is a schematic diagram of the structure of the chemical injection device of the present invention;

[0033] Among them: 1. Ground workstation; 2. Workbench; 3. Ultrasonic generator; 4. Display; 5. Cable; 6. Transmission component; 7. Pipe string; 8. Ultrasonic vibration system; 9. Near-source formation; 10. Original formation; 11. Injection pipeline; 12. Chemical injection device;

[0034] 51. Wrapping layer; 52. Steel wire; 53. Signal line; 54. Power line; 55. Hollow tube;

[0035] 81. round tube; 82. adapter; 83. longitudinal vibration transducer; 84. tester; 85. lead wire;

[0036] 121. Liquid storage tank; 122. Valve; 123. Flow meter; 124. Pressure pump. DETAILED DESCRIPTION

[0037] The present invention will be further described below by way of embodiments in conjunction with the accompanying drawings, but is not limited thereto.

[0038] Embodiment 1:

[0039] like Figure 1-5 As shown, this embodiment provides a field operation device for improving oil and gas recovery by ultrasonic physical-chemical synergistic production increase, including a ground workstation 1, a cable 5, a pipe string 7, a chemical injection device 12 and an ultrasonic vibration system 8, wherein:

[0040] A pipe string 7 is arranged in the wellbore, and the ground workstation 1 and the chemical injection device 12 are both connected with a cable 5. The cable 5 passes through the pipe string 7 through a transmission component 6 and is arranged in the wellbore. An ultrasonic vibration system 8 is arranged at the end of the cable 5, and the transmission component 6 is an existing pulley assembly.

[0041] The ground workstation 1 comprises a workbench 2, a control system, an ultrasonic generator 3 and a display 4. The workbench 2 is provided with a control system, the control system is connected to the ultrasonic generator 3, the display 4 and a chemical injection device 12, and the ultrasonic generator 3 is connected to a cable 5.

[0042] The cable 5 includes a wrapping layer 51, a signal line 53, a power line 54 and a hollow tube 55. The signal line 53, the power line 54 and the hollow tube 55 are arranged in the wrapping layer 51. The signal line 53 is composed of 7 copper wires wound together. One end of the signal line 53 is connected to the ultrasonic generator 3, and the other end is connected to the ultrasonic vibration system 8. The power line 54 is connected to the ultrasonic vibration system 8. One end of the hollow tube 55 is connected to the chemical injection device 12.

[0043] The wrapping layer 51 is made of cross-linked polyethylene, and steel wires 52 are uniformly doped in the cross-linked polyethylene to improve the overall strength.

[0044] The ultrasonic vibration system 8 includes a shell, a circular tube 81, an adapter 82, a longitudinal vibration transducer 83 and a tester 84. The adapter 82 is arranged at one end of the shell, and a circular tube (i.e., a waveguide system) is arranged in the middle of the shell. Longitudinal vibration transducers 83 are respectively arranged at both ends of the circular tube 81. The two longitudinal vibration transducers 83 are respectively connected to the adapter 82 through the lead 85, and the adapter 82 is connected to the signal line 53 in the cable. A tester 84 is arranged at the other end of the shell. The tester 84 is used to test the bottom hole temperature, pressure and flow rate of the fluid, and corresponding sensors can be used for testing.

[0045] The chemical injection device 12 includes a liquid storage tank 121, a valve 122, a flow meter 123 and a pressure pump 124. The liquid storage tank 121 is connected to the inlet of the pressure pump 124 through a pipeline. The valve 122 and the flow meter 123 are provided on the connecting pipeline between the liquid storage tank 121 and the pressure pump 124. The outlet of the pressure pump 124 is connected to the hollow tube 55 of the cable through the injection pipeline 11.

[0046] The working method of the above-mentioned ultrasonic physical-chemical synergistic production increase and oil and gas recovery efficiency field operation device comprises the following steps:

[0047] (1) lowering the ultrasonic vibration system 8 through the pipe string into the wellbore so that the ultrasonic vibration system 8 is near the source formation 9;

[0048] (2) The ultrasonic generator 3 generates a high-frequency electrical signal, which is transmitted to the longitudinal vibration transducer 83 by the cable 5 to generate ultrasonic waves. The longitudinal vibration of the ultrasonic waves is converted into radial vibrations through the circular tube 81. Both ends of the circular tube are excited by the longitudinal vibration transducers. When the length of the circular tube 81 is an odd multiple of the half wavelength corresponding to the operation of the vibrator, the two longitudinal vibration transducers 83 are excited in phase; when the length of the circular tube 81 is an even multiple of the half wavelength corresponding to the operation of the vibrator, the two longitudinal vibration transducers 83 are excited in anti-phase. The longitudinal vibration transducer 83 operates at the longitudinal-diameter coupling resonance frequency of the circular tube, exciting the circular tube to generate longitudinal-diameter coupling vibrations, converting the input longitudinal vibrations into radial vibrations and radiating them into the surrounding strata. The tubular ultrasonic vibration system designed by the present invention radiates ultrasonic waves along the circular tube, and the radiation area is larger than that of ordinary sandwich transducers. At the same time, the radial vibration radiates sound energy to the surroundings, making the sound field more uniform.

[0049] (3) Valve 122 is opened, and pressure pump 124 is started to inject the chemical agent stored in liquid storage tank 121 into the wellbore through cable 5 and release it in the target layer;

[0050] (4) After ultrasonic waves contact the chemical agents in the wellbore, they vibrate at high frequencies to produce cavitation. On the one hand, they remove wax and unblock plugging in the perforated section and near-source formation in the wellbore, and produce cracks in the near-source formation 9. On the other hand, they combine with the injected chemical agents to promote the penetration of the chemical agents and increase the chemical reaction rate to achieve a better production increase effect. After ultrasonic physical-chemical transformation, the near-source formation 9 is effectively dewaxed and unblocked, improving the flow conditions of oil and gas, and the crude oil in the original formation 10 can flow smoothly to the bottom of the well, thereby increasing the overall recovery rate.

[0051] When working, if encountering high porosity and high permeability reservoirs, only ultrasonic operation is used. If encountering low porosity, low permeability reservoirs and heavy oil reservoirs, a combination of ultrasonic operation and chemical agents is used.

[0052] During specific work, through the control system, the staff can monitor the downhole situation in real time, and optimize the operation effect by manually or automatically adjusting the power, frequency and action time of the ultrasonic operation. If the pressure and flow rate of the chemical injection device increase, the power and time of the ultrasonic operation will be automatically reduced; if the pressure and flow rate of the chemical injection device remain unchanged after increasing, the ultrasonic operation can be stopped; if the pressure and flow rate decrease, the power of the ultrasonic operation will be increased. Each operation parameter will be recorded in the control system. The best construction parameters for each operation can be obtained by recording. After multiple constructions, the system will automatically select the currently suitable best construction parameters based on the operation parameters recorded in the early stage.

[0053] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A field operation device for improving oil and gas recovery rate by ultrasonic physical-chemical synergistic production increase, characterized in that: It includes a ground workstation, cables, pipe strings, chemical injection devices and ultrasonic vibration systems, among which: A pipe string is arranged in the wellbore, and a ground workstation and a chemical injection device are connected with cables. The cables pass through the pipe string and are arranged in the wellbore, and an ultrasonic vibration system is arranged at the end of the cables.

2. The ultrasonic physical-chemical synergistic production-increasing and oil and gas recovery efficiency-enhancing field operation device according to claim 1, characterized in that: The ground workstation comprises a workbench, a control system, an ultrasonic generator and a display. The workbench is provided with a control system, the control system is connected with the ultrasonic generator, the display and a chemical injection device, and the ultrasonic generator is connected with a cable.

3. The ultrasonic physical-chemical synergistic production-increasing and oil and gas recovery efficiency-enhancing field operation device according to claim 2, characterized in that: The cable includes a wrapping layer, a signal line, a power line and a hollow tube. The signal line, the power line and the hollow tube are arranged in the wrapping layer. One end of the signal line is connected to an ultrasonic generator, and the other end is connected to an ultrasonic vibration system. The power line is connected to the ultrasonic vibration system, and one end of the hollow tube is connected to a chemical injection device.

4. The field operation device for improving oil and gas recovery rate by ultrasonic physical-chemical synergistic production increase as claimed in claim 3, characterized in that: The wrapping layer is made of cross-linked polyethylene, in which steel wires are uniformly doped.

5. The field operation device for improving oil and gas recovery rate by ultrasonic physical-chemical synergistic production increase as claimed in claim 3, characterized in that: The ultrasonic vibration system includes a shell, a round tube, an adapter, a longitudinal vibration transducer and a tester. An adapter is provided at one end of the shell, a round tube is provided in the middle of the shell, and longitudinal vibration transducers are provided at both ends of the round tube. The two longitudinal vibration transducers are connected to the adapter through leads respectively, and the adapter is connected to the signal line in the cable. A tester is provided at the other end of the shell, and the tester is used to test the bottom hole temperature, pressure and flow rate of the fluid.

6. The ultrasonic physical-chemical synergistic production-increasing and oil and gas recovery efficiency-enhancing field operation device according to claim 5, characterized in that: The chemical injection device includes a liquid storage tank, a valve, a flow meter and a pressure pump. The liquid storage tank is connected to the pressure pump inlet through a pipeline. The connecting pipeline between the liquid storage tank and the pressure pump is provided with a valve and a flow meter. The pressure pump outlet is connected to a hollow tube with a cable through an injection pipeline.

7. The working method of the field operation device for increasing oil and gas recovery by ultrasonic physical-chemical synergistic production as claimed in claim 6 is characterized in that: Here are the steps: (1) lowering the ultrasonic vibration system through the pipe string into the wellbore so that the ultrasonic vibration system is near the source formation; (2) The ultrasonic generator generates a high-frequency electrical signal, which is transmitted to the longitudinal vibration transducer by the cable to generate ultrasonic waves. When the length of the circular tube is an odd multiple of the half wavelength corresponding to the working vibrator, the two longitudinal vibration transducers are excited in phase; when the length of the circular tube is an even multiple of the half wavelength corresponding to the working vibrator, the two longitudinal vibration transducers are excited in anti-phase. The longitudinal vibration transducer operates at the longitudinal-diameter coupling resonance frequency of the circular tube, exciting the circular tube to generate longitudinal-diameter coupling vibration, converting the input longitudinal vibration into radial vibration and radiating it into the surrounding formations; (3) The valve is opened, the pressure pump is started, and the chemical agents stored in the liquid storage tank are injected into the wellbore through the cable and released in the target layer; (4) After ultrasonic waves come into contact with the chemical agents in the wellbore, they vibrate at high frequencies and produce cavitation. On the one hand, they remove wax and unblock plugs in the perforated section and near-source formation in the wellbore, creating cracks in the near-source formation. On the other hand, they combine with the injected chemical agents to promote the penetration of the chemical agents and increase the chemical reaction rate. After ultrasonic physical-chemical transformation, the near-source formation is dewaxed and unblocked, and the crude oil in the original formation can flow smoothly to the bottom of the well.

8. The working method of the field operation device for increasing oil and gas recovery rate by ultrasonic physical-chemical synergistic production as claimed in claim 7, characterized in that: When working, if encountering high porosity and high permeability reservoirs, only ultrasonic operation is used. If encountering low porosity, low permeability reservoirs and heavy oil reservoirs, a combination of ultrasonic operation and chemical agents is used.

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