High-speed pressure carrier separated layer water injection method based on separated layer water injection device

Abstract

The invention discloses a high-speed pressure carrier separated layer water injection method based on a separated layer water injection device. The high-speed pressure carrier separated layer water injection method comprises the steps that 1, a command is sent to an underground injection allocator through a high-speed pressure carrier control system; 2, when the water nozzle is fully opened, the collected pressure wave data are subjected to composite coding in a positive pulse number and pulse width combination mode; 3, generating a high-speed pressure carrier through the high-speed pressure carrier control system, sending a command to the underground injection allocator, opening or closing the underground injection allocator, and testing the water injection rate under different pressures; 4, the high-speed pressure carrier control system sends an instruction to the underground injection allocator, a water nozzle is opened and closed from bottom to top in sequence, a seal examination test of the packer is completed, and a seal examination test result is transmitted to the high-speed pressure carrier control system; and 5, the high-speed pressure carrier control system sends an instruction to the underground injection allocator, the opening degree of a water nozzle of the underground injection allocator is adjusted, and injection allocation of flow of each layer is completed. The device can be suitable for water injection wells with different well conditions, and the efficiency of layered water injection is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of stratified water injection in petroleum exploitation, and in particular is a high-speed pressure carrier stratified water injection method based on a stratified water injection device. Background Art

[0002] As the exploitation time of oil and gas fields increases, the reservoir pressure and oil content continue to decline, the oil well production is greatly reduced, and even the spraying and production will stop, resulting in a large amount of oil remaining underground that cannot be exploited. In order to make up for the underground deficit caused by the exploitation of crude oil, maintain and increase the reservoir pressure, achieve high and stable production of the oil field, and obtain a higher recovery rate, water injection must be carried out on the oil layer, and the position of water injection technology in oil field development is becoming more and more important.

[0003] Water injection is the process of injecting water into oil layers using injection wells to supplement and maintain oil layer pressure. Due to the differences in pressure and permeability of each layer, the water injection system of each oil layer needs to be managed separately during water injection. By controlling the water injection into the high permeability layer and strengthening the water injection into the medium and low permeability layers, the purpose of refined water injection can be achieved to ensure the maximum oil field recovery rate.

[0004] However, existing water injection methods all use fixed-coded pressure carriers, which cannot adaptively implement coding according to well conditions. Therefore, they are difficult to apply to detailed stratified water injection in different water injection wells. Summary of the invention

[0005] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a high-speed pressure carrier stratified water injection method based on a separate injection water injection device, which can be applied to water injection in different well conditions and improves the efficiency of stratified water injection.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] A high-speed pressure carrier layered water injection method based on a separate injection water injection device comprises the following steps:

[0008] Step 1: Sending a command to a downhole injection device through a high-speed pressure carrier control system;

[0009] Step 2: When the water tap is fully opened, the collected pressure wave data is compound-encoded in the form of the number of positive pulses plus the pulse width, where the pulse width is a time unit, expressed as:

[0010] T=1000*ln(K)+100*ln(L)+10N

[0011] In the formula, K represents the pressure attenuation coefficient, L represents the transmission distance, and N represents the number of rising edge changes, in seconds;

[0012] Step 3: Generate a high-speed pressure carrier through a high-speed pressure carrier control system, send a rotation injection command to the downhole injector, so that the downhole injector is opened or closed in sequence, and perform water injection volume tests under different pressures to determine the water absorption of each layer in the well;

[0013] Step 4: Send instructions to the downhole injector through the high-speed pressure carrier control system, turn on and off the water nozzles of the injector from bottom to top in sequence, complete the sealing test of multiple packers, and transmit the sealing test results to the high-speed pressure carrier control system through high-speed pressure waves;

[0014] Step 5. When the water nozzle of the injection device is fully opened again, the high-speed pressure carrier control system performs composite encoding on the collected pressure carrier data according to the injection volume under different pressures collected in step 3, thereby changing the injection volume. The high-speed pressure carrier control system sends instructions to the downhole injection device to adjust the opening of the water nozzle of the downhole injection device to complete the injection of the flow rate of each layer.

[0015] Furthermore, the high-speed pressure carrier control system includes a controller and a high-speed pressure generating device and a first pressure transmitter connected thereto, wherein: the high-speed pressure generating device is used to generate a high-speed pressure carrier; the first pressure transmitter is used to receive downhole pressure wave data;

[0016] The controller performs composite encoding on the pressure wave data collected by the first pressure transmitter to control the switch state of the high-speed pressure generating device;

[0017] The downhole injection device receives and analyzes the high-speed pressure carrier wave generated by the high-speed pressure generating device, thereby obtaining the control instruction of the controller and adjusting the opening of the water nozzle.

[0018] Furthermore, the high-speed pressure carrier control system also includes a second pressure transmitter for monitoring the pressure of the water supply pipeline, and the second pressure transmitter is connected to the controller.

[0019] Furthermore, the high-speed pressure carrier control system also includes a flow transmitter for monitoring the flow rate of the entire well, and the flow transmitter is connected to the controller.

[0020] Further, the downhole packer is located between two downhole injectors and forms a channel for liquid to pass therethrough, and the injectors are connected to the oil pipe;

[0021] The downhole dispenser comprises a motor circuit control nipple, a battery nipple, a motor and a water nozzle. The motor circuit control nipple is connected to a controller, and the motor circuit control nipple and the motor are respectively connected to the battery nipple. The motor is controlled by the motor circuit control nipple to adjust the opening of the water nozzle.

[0022] Furthermore, the dispenser further comprises an upper joint and a lower joint, and the upper joint and the lower joint are respectively fixedly connected to the opposite ends of two adjacent oil pipes.

[0023] Furthermore, the downhole packer is a Y341 double-seal packer.

[0024] Furthermore, the self-high-speed pressure generating device is a booster valve.

[0025] Furthermore, the pressure attenuation coefficient K is 1 to 1.5.

[0026] Compared with the prior art, the present invention has the following technical effects:

[0027] The present invention sets the water nozzle opening time of the downhole dispenser in advance, so that the water nozzle of the downhole dispenser is in a fully open state at the expected time, which is convenient for the high-speed pressure carrier control system to collect the pressure wave changes in the well in real time and perform adaptive composite coding in combination with the number of positive pulses plus the pulse width. In the coding process, the pressure attenuation coefficient, the transmission distance of the pressure carrier and the number of rising edge changes are fully considered, thereby improving the efficiency and adaptability of carrier communication. Then, through one-key round injection, the water absorption of different layers in the well is mastered, and then, the water nozzles are closed from bottom to top in sequence to complete the sealing test of multiple downhole packers. Finally, the high-speed pressure carrier control system sends instructions to the downhole dispenser in the form of a high-speed pressure carrier to adjust the opening of the water nozzle and complete the injection of the flow rate of each layer. In short, the high-speed pressure carrier control system of the present invention can open the water nozzle at a preset time, perform adaptive composite coding on the collected pressure carrier data, thereby changing the injection volume, and then send instructions to the downhole dispensers of each layer to adjust the opening of each water nozzle, thereby improving the injection accuracy and efficiency of the water injection well, improving the labor efficiency of the operator, and solving the problem that the existing water injection method is difficult to adapt to different well conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 : Schematic diagram of the overall structure of the present invention;

[0029] Figure 2 : A schematic diagram of the structure of the downhole injection device of the present invention;

[0030] Figure 3 : Carrier coding diagram of the present invention;

[0031] Figure 4 : The carrier coding bitmap of the present invention.

[0032] In the figure: 1. high-speed pressure carrier control system; 11. controller; 12. second pressure transmitter; 13. high-speed pressure generating device; 14. second pressure transmitter; 15. flow transmitter; 2. downhole packer; 3. downhole injector; 31. upper joint; 32. motor circuit control short section; 33. battery short section; 34. water nozzle; 35. lower joint; 4. oil pipe. DETAILED DESCRIPTION

[0033] The specific contents of the present invention are further explained in detail below in conjunction with embodiments.

[0034] like Figure 1-2 As shown, a stratified water injection device includes a high-speed pressure carrier control system 1 located on the ground for sending commands to and receiving data in a water injection well, an oil pipe 4 located in the well, a plurality of downhole packers 2 and a downhole injector 3, wherein the downhole packer 2 is used to stratify oil layers at different levels in the oil well, and the downhole packer 2 is located between two downhole injectors 3 and forms a channel for liquid to pass therethrough, and the injector 3 is connected to the oil pipe 4. Specifically, the injector further includes an upper joint 31 and a lower joint 35, and the upper joint 31 and the lower joint 35 are respectively fixedly connected to the opposite ends of two adjacent sections of the oil pipe 4;

[0035] The downhole injection device 3 includes a motor circuit control subsection 32, a battery subsection 33, a motor and a water nozzle 34. The battery subsection 33 supplies power to the motor circuit control subsection 32 and the motor. The motor circuit control subsection 32 is used to control the motor, and the opening of the water nozzle 34 is controlled by the motor to adjust the water injection amount of different layers.

[0036] The high-speed pressure carrier control system 1 includes a controller 11 and a second pressure transmitter 12 connected thereto for monitoring the pressure of the water supply pipeline, a high-speed pressure generating device 13 for generating a high-speed pressure carrier, a first pressure transmitter 14 for receiving downhole pressure wave data, and a flow transmitter 15 for monitoring the flow of the entire well. The controller 11 controls the switching state of the high-speed pressure generating device 13 and receives the pressure wave data from the second pressure transmitter 12 and the first pressure transmitter 14 and the flow data from the flow transmitter 15. The downhole dispenser 3 receives the high-speed pressure carrier generated by the high-speed pressure generating device 13 and parses it to obtain the control information of the controller 11.

[0037] Preferably, the specific structure of the downhole injector 3 can refer to the structure of the injector in Chinese invention patent CN109594957A, which can collect the internal pressure, temperature and injection flow rate of the oil well.

[0038] Preferably, the downhole packer 2 is a Y341 double-seal packer.

[0039] Preferably, the self-high-speed pressure generating device 13 is a booster valve.

[0040] A high-speed pressure carrier stratified water injection method based on a stratified water injection device comprises the following steps:

[0041] Step 1: Flow rate setting

[0042] The high-speed pressure carrier control system 1 sends instructions to the downhole dispenser 3 to preset the flow rate and the opening time of its nozzle. Specifically, the flow rate of the downhole dispenser 3 and the opening time of its nozzle are set by the controller 11. When the error of the downhole dispenser 3 reaches the preset range, the controller 11 sends instructions to automatically adjust, thereby improving the accuracy of the injection.

[0043] Step 2: Composite coding

[0044] When the preset opening time is reached, the water nozzle is fully opened, and the high-speed pressure carrier control system 1 uses the combination of positive pulse number and pulse width to perform compound encoding on the collected pressure wave data, where the pulse width is a time unit, expressed as:

[0045] T=1000*ln(K)+100*ln(L)+10N

[0046] In the formula, K represents the pressure attenuation coefficient, the value range of K is 1 to 1.5, L represents the transmission distance, and N represents the number of rising edge changes, the unit is s;

[0047] Specifically, the controller 11 uses the combination of positive pulse number and pulse width to perform compound encoding on the pressure wave data collected by the first pressure transmitter 14, so as to be applicable to different well conditions, simplify the command, and achieve the purpose of high-speed control, such as Figure 3 As shown in the figure, it is precisely because the high-speed pressure carrier encodes different commands and adopts different encoding combinations according to different unit times T, thus realizing high-speed pressure carrier encoding, achieving precise control of the water nozzles of the dispensers at different layers, and realizing the purpose of refined water injection. In addition, the transmission rate of the carrier data can be increased by reducing T;

[0048] Step 3: One-click betting

[0049] A high-speed pressure carrier control system 1 generates a high-speed pressure carrier, and sends a rotation injection command to the downhole injector 3, so that multiple downhole injectors 3 are opened or closed in sequence, and water injection volume tests are performed under different pressures to determine the water absorption of each layer in the well;

[0050] Specifically, the controller 11 controls the opening and time of the high-speed pressure generating device 13, generates a pressure wave coding command, and sends it to the downhole injector 3, which parses and executes the command to complete the water nozzle control;

[0051] Step 4: One-click seal verification

[0052] Send instructions to the downhole injector 3 through the high-speed pressure carrier control system 1, and turn on and off the water nozzles of the injector 3 from bottom to top in sequence to complete the sealing test of multiple downhole packers 2. The sealing test results are transmitted to the high-speed pressure carrier control system 1 in the form of high-speed pressure waves;

[0053] Specifically, the controller 11 sends instructions to the downhole injector 3, and sequentially switches the water nozzles of the injector 3 from bottom to top to complete the sealing test of multiple downhole packers 2. The sealing test results are transmitted to the controller 11 in the form of high-speed pressure waves.

[0054] Step 5, when the water nozzle of the injection device 3 is fully opened again, the high-speed pressure carrier control system 1 performs composite encoding on the collected pressure wave data according to the water injection amount under different pressures collected in step 3, thereby changing the water injection amount. The high-speed pressure carrier control system 1 sends instructions to the downhole injection device 3 in the form of a high-speed pressure carrier to adjust the water nozzle opening of the downhole injection device 3 to complete the injection of the flow rate of each layer;

[0055] Specifically, whenever the water nozzle is fully opened, the controller 11 performs composite encoding on the pressure wave data collected by the first pressure transmitter 14 according to the water injection amount under different pressures collected in step 3, thereby changing the water injection amount. The controller 11 controls the opening of the high-speed pressure generating device 13, and uses the high-speed pressure generating device 13 to generate a high-speed pressure carrier to transmit instructions to the downhole injection device 3, that is, the controller 11 uses the following method: Figure 4 The carrier coding bitmap shown transmits a command to the motor circuit control sub 32, thereby using the motor circuit control sub 32 to control the motor, and through the action of the motor, the opening of the water nozzle 34 is adjusted, thereby achieving the allocation of flow rates in each layer;

[0056] By repeating step 5 many times, the water injection volume can be changed regularly according to the change of the water injection volume in the well through composite coding, so as to accurately realize the injection of the flow rate of each layer;

[0057] During the water injection process, the pressure of the water supply pipeline and the total well flow are respectively collected through the second pressure transmitter 12 and the flow transmitter 15, so as to obtain the water injection situation in real time.

Claims

1. A high-speed pressure carrier stratified water injection method based on a stratified water injection device, characterized in that: The steps include: Step 1: Sending a command to a downhole injection device (3) via a high-speed pressure carrier control system (1); Step 2: When the water nozzle is fully opened, the high-speed pressure carrier control system (1) uses the combination of positive pulse number and pulse width to perform composite encoding on the collected pressure wave data, where the pulse width is a time unit and is expressed as: T=1000*ln(K)+100*ln(L)+10N In the formula, K represents the pressure attenuation coefficient, L represents the transmission distance, and N represents the number of rising edge changes, in seconds; Step 3: Generate a high-speed pressure carrier through the high-speed pressure carrier control system (1), send a rotation injection command to the downhole injector (3), so that multiple downhole injectors (3) are opened or closed in sequence, and water injection volume tests are performed under different pressures to determine the water absorption of each layer in the downhole; Step 4: Sending instructions to the downhole injector (3) through the high-speed pressure carrier control system (1), switching the water nozzles of the injector (3) from bottom to top in sequence, completing the sealing test of multiple downhole packers (2), and transmitting the sealing test results to the high-speed pressure carrier control system (1) in the form of high-speed pressure waves; Step 5, when the water nozzle of the injection device (3) is fully opened again, the high-speed pressure carrier control system (1) performs composite encoding on the collected pressure wave data according to the water injection volume under different pressures collected in step 3, thereby changing the water injection volume, and sending instructions to the downhole injection device (3) in the form of a high-speed pressure carrier to adjust the water nozzle opening of the downhole injection device (3) to complete the injection of each layer flow.

2. The high-speed pressure carrier stratified water injection method based on the stratified water injection device according to claim 1 is characterized in that: The high-speed pressure carrier control system (1) comprises a controller (11) and a high-speed pressure generating device (13) and a first pressure transmitter (14) connected thereto, wherein: the high-speed pressure generating device (13) is used to generate a high-speed pressure carrier; the first pressure transmitter (14) is used to receive downhole pressure wave data; The controller (11) performs composite encoding on the pressure wave data collected by the first pressure transmitter (14) to control the on / off state of the high-speed pressure generating device (13); The downhole injection device (3) receives and analyzes the high-speed pressure carrier generated by the high-speed pressure generating device (13), and adjusts the opening of the water nozzle.

3. The high-speed pressure carrier stratified water injection method based on the stratified water injection device according to claim 2 is characterized in that: The high-speed pressure carrier control system (1) further comprises a second pressure transmitter (12) for monitoring the pressure of the water supply pipeline, and the second pressure transmitter (12) is connected to the controller (11).

4. The high-speed pressure carrier stratified water injection method based on the stratified water injection device according to claim 2 or 3, characterized in that: The high-speed pressure carrier control system (1) also includes a flow transmitter (15) for monitoring the flow rate of the entire well, and the flow transmitter (15) is connected to the controller (11).

5. The high-speed pressure carrier stratified water injection method based on the stratified water injection device according to any one of claims 1 to 3, characterized in that: The downhole packer (2) is located between two downhole injectors (3) and forms a channel for liquid to pass therethrough. The injectors (3) are connected to the oil pipe (4). The downhole dispenser (3) comprises a motor circuit control nipple (32), a battery nipple (33), a motor and a water nozzle (34); the motor circuit control nipple (32) is connected to a controller (11); the motor circuit control nipple (32) and the motor are respectively connected to the battery nipple (33); the motor is controlled by the motor circuit control nipple (32) to adjust the opening of the water nozzle (34).

6. The high-speed pressure carrier stratified water injection method based on the stratified water injection device according to claim 5 is characterized in that: The dispenser (3) further comprises an upper joint (31) and a lower joint (35), wherein the upper joint (31) and the lower joint (35) are respectively fixedly connected to the opposite ends of two adjacent oil-saving pipes (4).

7. The high-speed pressure carrier stratified water injection method based on the stratified water injection device according to any one of claims 1 to 3, characterized in that: The downhole packer (2) is a Y341 double-seal packer.

8. The high-speed pressure carrier stratified water injection method based on the stratified water injection device according to claim 2 or 3, characterized in that: The self-high-speed pressure generating device (13) is a pressure boosting valve.

9. The high-speed pressure carrier stratified water injection method based on the stratified water injection device according to any one of claims 1 to 3, characterized in that: The pressure attenuation coefficient K is 1 to 1.5.

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