Real-time monitoring and dynamic adjusting device for air thermochemical oil displacement process

Abstract

The invention relates to the technical field of oil displacement, and discloses an air thermochemical oil displacement process real-time monitoring and dynamic adjusting device which comprises an air compressor, an oil displacement sensor and a controller. The gas supply assembly comprises an air injection pipeline, a hydrocarbon gas injection device and a nitrogen generation device, and a flow meter and a flow control valve are mounted in each pipeline; the temperature sensor is used for monitoring crude oil temperature; the gas monitor is used for monitoring whether oxygen is discharged from the production well or not; and the control system is used for receiving the monitoring information and adjusting the conveying proportion of each gas through a flow control valve. The bottom temperature and top oxygen of the production well are monitored through the temperature sensor and the gas monitor, the controller system processes monitored data, the injection amount of all gases is controlled through the flow control valve, the temperature is made to be within the safe range, the oil displacement effect is guaranteed, and meanwhile the oil displacement safety is improved.

Description

Technical Field

[0001] The invention relates to the technical field of oil recovery, in particular to a real-time monitoring and dynamic adjustment device for an air thermochemical oil recovery process. Background Art

[0002] Air thermochemical flooding is a technology that improves crude oil recovery. It uses an air compressor to transport gas to an injection well, and uses an ignition device to ignite the gas and ignite the oil layer to form a combustion zone. The heat generated by the combustion increases the temperature of the oil reservoir. The increased temperature reduces the viscosity of the crude oil, increases the fluidity of the crude oil, and makes it easier to flow out of the oil reservoir. The high temperature will also cause thermal expansion and thermal cracking of the rocks in the oil reservoir, improve the permeability of the reservoir, and increase the fluidity of the crude oil and the gas generated by the combustion. The flow of the oil flows to the production well through the connection of the reservoir and is recovered in the production well, thereby achieving the purpose of improving the recovery rate.

[0003] However, the thermochemical oil recovery site requires that the production wells cannot produce oxygen and the bottom temperature of the production wells cannot be too high. When the production wells produce oxygen, it indicates that the combustion is incomplete and there may be unburned hydrocarbon gases. These gases may undergo secondary combustion or explosion after contacting oxygen in the air, posing serious safety hazards. In addition, oxygen discharge may also cause fire or explosion risks, threatening the safety of on-site operators and equipment. When the temperature is too high and exceeds the heat resistance limit of the downhole equipment, it will cause equipment damage or failure. Excessive temperature may cause excessive expansion and rupture of reservoir rocks, forming too many cracks, resulting in unstable reservoir structure. At the same time, excessive temperature may also lead to uncontrolled combustion, making it difficult to adjust and control the advancement speed of the combustion front. When the combustion front advances too quickly, unburned oil and gas mixture may enter the production well, increasing safety risks. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a real-time monitoring and dynamic adjustment device for the air thermochemical oil recovery process, which solves the problem in the prior art that the on-site production wells in the thermochemical oil recovery cannot produce oxygen and the bottom temperature of the production wells cannot be too high, which easily causes safety accidents when oxygen is produced or the temperature is too high.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: a real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process, comprising:

[0006] An air compressor is placed at the wellhead of the injection well and is used to transport gas into the injection well;

[0007] A gas supply assembly, which includes an air injection pipeline, a hydrocarbon gas injection device and a nitrogen generation device, all of which are individually connected to the air compressor, and each of the pipelines is equipped with a flow meter and a flow control valve for monitoring and controlling the delivery volume of each gas;

[0008] An ignition device, which is located at the bottom of the injection well and is connected to the output end of the air compressor and is used to ignite the air and crude oil at the bottom of the well;

[0009] Temperature sensor, located at the bottom of the production well, used to monitor the crude oil temperature;

[0010] Gas monitors, located at the top of the production well, are used to monitor whether there is oxygen discharge from the production well;

[0011] The control system is connected with the flow control valve, the flow meter, the temperature sensor and the gas monitor, and is used for receiving information from the flow meter, the temperature sensor and the flow control valve, and adjusting the delivery ratio of each gas through the flow control valve.

[0012] Preferably, a gas mixer is provided between the air compressor and the gas supply assembly, one side of the gas mixer is connected to the input end of the air compressor and the other side is connected to the pipeline, and is used to mix the gases and supply them to the air compressor.

[0013] Preferably, the control system includes a controller, a signal processing module and a signal receiving module;

[0014] The flow meter is used to provide the signal receiving module with the real-time outflow value of the gas in each pipeline;

[0015] The temperature sensor is used to provide the signal receiving module with a real-time temperature value of the bottom of the production well;

[0016] The gas monitor is used to provide the signal receiving module with real-time oxygen data at the wellhead of the production well;

[0017] The signal receiving module is used to transmit the above data to the signal processing module;

[0018] The signal processing module is used to receive and process the data transmitted by the signal receiving module, and transmit it to the controller after analyzing it;

[0019] The controller adjusts the opening and closing degree of the flow control valve according to the analyzed data.

[0020] Preferably, the control system adjusts the flow control valves of each gas pipeline in real time according to the feedback data from the temperature sensor and the gas monitor to adjust the ratio between the gases, specifically including:

[0021] Step 1: When the bottom hole temperature is too high, reduce the air content and increase the nitrogen ratio by the following formula:

[0022]

[0023]

[0024] Step 2: When oxygen is detected in the production well, the nitrogen content is increased and the air ratio is reduced according to the following formula:

[0025]

[0026]

[0027] Step 3: When the temperature is detected to be too low, increase the air content and increase the hydrocarbon gas combustion by the following formula:

[0028]

[0029]

[0030] Among them, A new is the adjusted air flow, A1 is the current air flow, N new is the adjusted nitrogen flow rate, N1 is the current nitrogen flow rate, T1 is the current bottom hole temperature, T2 is the ideal bottom hole temperature, T3 is the maximum allowable bottom hole temperature, T4 is the minimum allowable bottom hole temperature, N2 is the maximum nitrogen flow rate, O1 is the monitored oxygen content, O2 is the maximum allowable oxygen content, H new is the adjusted hydrocarbon gas flow rate, H1 is the current hydrocarbon gas flow rate, A2 is the maximum air flow rate, and H2 is the maximum hydrocarbon gas flow rate.

[0031] Preferably, the gas mixer is a static mixer, which is used to mix the gases before entering the air compressor.

[0032] Preferably, the control system further includes a storage module for storing information received by the signal receiving module and information processed by the signal processing module.

[0033] Preferably, the control system further comprises a transmission module for performing wired / wireless transmission of the information received by the signal receiving module and the information processed by the signal processing module.

[0034] Preferably, the storage module is connected to the transmission module via an analysis module, the analysis module is used to analyze the storage data of the storage module and generate logs, and the transmission module is used to perform wired / wireless transmission of the logs generated by the analysis module.

[0035] Working principle: When in use, first connect the air injection pipeline to the gas mixer. At this time, the gas mixer will transport air to the air compressor, and the air compressor can be used to transport air to the ignition device. Since the ignition device is located in the oil layer, the ignition device will ignite the oil layer in contact with it to achieve crude oil combustion. Then, as the air is continuously injected, the combustion zone will continue to advance toward the production well, and the heat released during combustion will reduce the viscosity of the surrounding crude oil, causing thermal cracks to form in the reservoir to increase permeability, thereby improving oil recovery efficiency. In addition, during the combustion process, the temperature sensor can monitor the crude oil temperature at the bottom of the production well. When the temperature is too high and exceeds the threshold, the temperature sensor will transmit the signal to the signal receiving module, which can transmit the signal to the signal processing module. At this time, the signal processing module processes the signal and drives the flow control valve through the controller. The flow control valve on the air injection pipeline is used to reduce the amount of air entering the gas mixer, and the nitrogen generation device The flow control valve on increases the amount of nitrogen entering the gas mixer, so as to reduce the temperature of the oil layer heated by the combustion of the ignition device and avoid excessive temperature. When the gas monitor detects that oxygen is discharged from the wellhead of the production well, it means that there is a lot of air in the oil layer, resulting in incomplete combustion of the air and discharge from the production well. At this time, the sensor monitoring transmits the signal to the signal receiving module, and then reduces the air injection and increases the nitrogen injection through the signal processing module and the controller. When the temperature measured by the temperature sensor is low, it means that the combustion effect of the oil layer is poor and the combustion zone may fail. At this time, after the temperature sensor signal is transmitted to the signal receiving module, the signal processing module and the controller drive the flow control valve to increase the amount of air entering the gas mixer, and at the same time, the hydrocarbon gas injection device injects hydrocarbon gas into the gas mixer. Hydrocarbon gas can be used to assist the combustion of the oil layer at the bottom of the oil well and improve the combustion heat release efficiency, thereby ensuring the effect of oil displacement and avoiding safety hazards caused by excessive temperature and oxygen leakage.

[0036] The present invention provides a real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process. It has the following beneficial effects:

[0037] 1. The present invention can monitor the temperature at the bottom of the production well through a temperature sensor, and can monitor whether there is oxygen discharge from the top of the production well through a gas monitor. The controller system processes the monitoring data of the temperature sensor and the gas monitor, and controls the injection amount of air, nitrogen and hydrocarbon gas through a flow control valve to keep the temperature at the bottom of the production well within a safe range, thereby ensuring the oil recovery effect while improving the safety of the oil recovery process.

[0038] 2. The present invention provides a gas mixing device between the gas supply assembly and the air compressor, so that the various gases can be evenly mixed before entering the air compressor, thereby improving the complete combustion of the mixed gas and avoiding the influence of incomplete combustion on the overall monitoring results and the accuracy of dynamic adjustment, thereby further improving the oil recovery effect and the safety in the oil recovery process. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a structural schematic diagram of the present invention;

[0040] Figure 2 A schematic diagram of the connection of the gas supply assembly of the present invention;

[0041] Figure 3 It is a connection diagram of the control system of the present invention;

[0042] Figure 4 It is a connection block diagram of the present invention.

[0043] Among them, 1. gas supply assembly; 2. air injection pipeline; 3. hydrocarbon gas injection device; 4. nitrogen generation device; 5. flow meter; 6. flow control valve; 7. gas mixer; 8. air compressor; 9. temperature sensor; 10. gas monitor; 11. ignition device. DETAILED DESCRIPTION

[0044] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0045] Example:

[0046] Please refer to the attached Figure 1 -Attached Figure 4The embodiment of the present invention provides a real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process, including: an air compressor 8, which is placed at the wellhead of the injection well and is used to transport gas to the injection well; a gas supply component 1, which includes an air injection pipeline 2, a hydrocarbon gas injection device 3 and a nitrogen generation device 4, all of which are separately connected to the air compressor 8, and each pipeline is installed with a flow meter 5 and a flow control valve 6 for monitoring and controlling the delivery amount of each gas; an ignition device 11, which is located at the bottom of the injection well and is connected to the output end of the air compressor 8, and is used to heat the air and crude oil at the bottom of the well to achieve crude oil combustion; a temperature sensor 9, which is located at the bottom of the production well and is used to monitor the crude oil temperature; a gas monitor 10, which is located at the top of the production well and is used to monitor whether there is oxygen discharge from the production well; a control system, which is connected to the flow control valve 6, the flow meter 5, the temperature sensor 9 and the gas monitor 10, and is used to receive information from the flow meter 5, the temperature sensor 9 and the flow control valve 6, and adjust the delivery ratio of each gas through the flow control valve 6.

[0047] The corresponding gas can be provided to the air compressor 8 through the air injection pipeline 2, the hydrocarbon gas injection device 3 and the nitrogen generation device 4, and the gas can be transported to the bottom of the injection well through the air compressor 8. The gas can be ignited by using the ignition device 11, and it is in the oil layer, so it will cause the oil layer to burn and generate a combustion zone. The heat released by the combustion is used to heat the surrounding crude oil to reduce its viscosity, so that thermal cracks are formed in the reservoir to increase the permeability, thereby ensuring the oil recovery effect. The ignition device 11 is set as a fire drive combustion tube, and the temperature sensor 9 can be used to monitor the temperature of the oil layer at the bottom of the production well, and the gas monitor 10 can monitor whether there is oxygen discharge from the wellhead of the production well. When the two transmit the results to the control system, the control system controls the proportion of each gas transported to the inside of the injection well through the flow control valve 6, that is, when the temperature is too high, the air volume is reduced and the nitrogen volume is increased. When oxygen is discharged from the inlet of the production well, the air volume is reduced and the nitrogen volume is increased. When the temperature is too low, the amount of air and hydrocarbon gas is increased, thereby maintaining the temperature at an optimal temperature, thereby ensuring the effect and safety of oil recovery.

[0048] Please refer to the attached Figure 1 and Figure 2 A gas mixer 7 is provided between the air compressor 8 and the gas supply assembly 1. One side of the gas mixer 7 is connected to the input end of the air compressor 8 and the other side is connected to the pipeline, and is used to mix the gases and supply them to the air compressor 8. The gas mixer 7 is a static mixer, and is used to mix the gases before entering the air compressor 8.

[0049] By arranging a gas mixer 7 between the air compressor 8 and the gas supply assembly 1, the air, nitrogen and hydrocarbon gases will be evenly mixed inside the mixer before entering the air compressor 8 and then transported to the air compressor 8, so as to ensure the combustion effect of the gas and make it fully burn, and avoid the impact of insufficient combustion on the overall monitoring results and dynamic adjustment accuracy. The gas mixer 7 uses a static mixer. Since the static mixer uses the flow characteristics of the gas in the pipeline to achieve mixing, and when two or more gases enter the mixer, various eddies and turbulences will be generated according to the fluid dynamics effect. These turbulences and eddies will cause mixing and diffusion between gas molecules, thereby achieving uniform mixing of the gas, so the uniformity of the gas mixing can be guaranteed.

[0050] Please refer to the attached Figure 3 and Figure 4 The control system includes a controller, a signal processing module and a signal receiving module; the flow meter 5 is used to provide the real-time outflow value of the gas in each pipeline to the signal receiving module; the temperature sensor 9 is used to provide the real-time temperature value of the bottom of the production well to the signal receiving module; the gas monitor 10 is used to provide the real-time oxygen data at the wellhead of the production well to the signal receiving module; the signal receiving module is used to transmit the above data to the signal processing module; the signal processing module is used to receive and process the data transmitted by the signal receiving module, and transmit it to the controller after analysis; the controller regulates the flow control valve 6 according to the analyzed data to achieve the purpose of adjusting the air output of each pipeline.

[0051] The flow meter 5 is installed in each gas supply pipeline to transmit the measured data to the signal receiving module. The temperature sensor 9 is installed at the bottom of the production well to transmit the temperature data to the signal receiving module. The gas monitor 10 is installed at the wellhead of the production well to monitor the oxygen content discharged from the production well in real time and transmit the monitoring data to the signal receiving module. The signal receiving module is equipped with multiple signal input ports, which can simultaneously receive multiple signals from the flow meter 5, the temperature sensor 9 and the gas monitor 10. The signal processing module is used to convert the analog signal from the sensor into a digital signal. The signal processing module has a built-in algorithm for real-time analysis and processing of the received data, and transmits the processing results to the controller. The controller can receive data from the signal processing module and dynamically adjust the opening of the flow control valve 6 according to the preset control strategy and real-time data, thereby realizing precise control of the gas flow of each pipeline.

[0052] Please refer to the attached Figure 1 -Attached Figure 4 The control system adjusts the flow control valves 6 of each gas pipeline in real time according to the feedback data of the temperature sensor 9 and the gas monitor 10 to adjust the ratio between the gases, specifically including:

[0053] Step 1: When the bottom hole temperature is too high, reduce the air content and increase the nitrogen content using the following formula:

[0054]

[0055]

[0056] Step 2: When oxygen is detected in the production well, the nitrogen content is increased and the air content is reduced by the following formula:

[0057]

[0058]

[0059] Step 3: When the temperature is detected to be too low, increase the air content and hydrocarbon gas content to aid combustion using the following formula:

[0060]

[0061]

[0062] Among them, A new is the adjusted air flow, A1 is the current air flow, N new is the adjusted nitrogen flow rate, N1 is the current nitrogen flow rate, T1 is the current bottom hole temperature, T2 is the ideal bottom hole temperature, T3 is the maximum allowable bottom hole temperature, T4 is the minimum allowable bottom hole temperature, N2 is the maximum nitrogen flow rate, O1 is the monitored oxygen content, O2 is the maximum allowable oxygen content, H new is the adjusted hydrocarbon gas flow rate, H1 is the current hydrocarbon gas flow rate, A2 is the maximum air flow rate, and H2 is the maximum hydrocarbon gas flow rate.

[0063] The formulas in steps one, two and three can provide an algorithm basis for the signal processing module to process data, thereby achieving the purpose of real-time regulation of the ratio of air, nitrogen and hydrocarbon gas delivered to the injection well.

[0064] Furthermore, the oil and gas produced from the production well can be separated, and then the hydrocarbon gas therein can be separated. At this time, the hydrocarbon gas can be connected to the hydrocarbon gas injection device, and then the hydrocarbon gas can be input into the injection well through the control system. When oil is driven to multiple production wells through one injection well, different air can be transported to different production wells by collecting the import data of multiple production wells.

[0065] Please refer to the attached Figure 3 and Figure 4The control system further includes a storage module for storing information received by the signal receiving module and information processed by the signal processing module. The control system further includes a transmission module for wirelessly transmitting information received by the signal receiving module and information processed by the signal processing module. The storage module is connected to the transmission module through the analysis module, the analysis module is used to analyze the storage data of the storage module and generate a log, and the transmission module is used to wirelessly transmit the log generated by the analysis module.

[0066] The analysis module is used to conduct in-depth analysis of the data in the storage module and generate detailed operation logs, trend analysis reports and performance evaluation reports. The storage module is used to store the original data received by the signal receiving module and the data processed by the signal processing module for a long time, and can save detailed operation logs, historical data and key parameters to facilitate subsequent analysis and troubleshooting. The log file records the details of the system operation, including the gas flow rate, bottom hole temperature, oxygen content and adjustment action of the flow control valve 6 at each time point, which is convenient for operators and engineers to view and use.

[0067] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process, characterized in that: include: An air compressor (8), the air compressor (8) being placed at the wellhead of the injection well, and the air compressor (8) being used to transport gas into the injection well; A gas supply assembly (1), the gas supply assembly (1) comprising an air injection pipeline (2), a hydrocarbon gas injection device (3) and a nitrogen generating device (4), the air injection pipeline (2), the hydrocarbon gas injection device (3) and the nitrogen generating device (4) are all individually connected to an air compressor (8), and flow meters (5) and flow control valves (6) are installed in the pipelines of the air injection pipeline (2), the hydrocarbon gas injection device (3) and the nitrogen generating device for monitoring and controlling the delivery amount of each gas; An ignition device (11), the ignition device (11) is located at the bottom of the injection well, the ignition device (11) is connected to the output end of the air compressor (8), and the ignition device (11) is used to ignite the air and crude oil at the bottom of the well; A temperature sensor (9), the temperature sensor (9) is located at the bottom of the production well and is used to monitor the temperature of the crude oil; A gas monitor (10), the gas monitor (10) being located at the top of the production well and used to monitor whether there is oxygen discharge from the production well; A control system, wherein the control system is connected to the flow control valve (6), the flow meter (5), the temperature sensor (9) and the gas monitor (10), and is used to receive information from the flow meter (5), the temperature sensor (9) and the flow control valve (6), and to adjust the delivery ratio of each gas through the flow control valve (6).

2. The real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process according to claim 1 is characterized in that: A gas mixer (7) is provided between the air compressor (8) and the gas supply assembly (1); one side of the gas mixer (7) is connected to the input end of the air compressor (8) and the other side is connected to a pipeline; the gas mixer (7) is used to mix the gases and supply them to the air compressor (8).

3. The real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process according to claim 1 is characterized in that: The control system includes a controller, a signal processing module and a signal receiving module; The flow meter (5) is used to provide the signal receiving module with the real-time outflow value of the gas in each pipeline; The temperature sensor (9) is used to provide the signal receiving module with a real-time temperature value of the bottom of the production well; The gas monitor (10) is used to provide the signal receiving module with real-time oxygen data at the wellhead of the production well; The signal receiving module is used to transmit the monitoring data to the signal processing module; The signal processing module is used to receive and process the data transmitted by the signal receiving module, and transmit it to the controller after analyzing it; The controller adjusts the opening and closing degree of the flow control valve (6) according to the analyzed data.

4. The real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process according to claim 3 is characterized in that: The control system adjusts the flow control valves (6) of each gas pipeline in real time according to the feedback data from the temperature sensor (9) and the gas monitor (10) to adjust the ratio between the gases, specifically including: Step 1: When the bottom hole temperature is too high, reduce the air content and increase the nitrogen content using the following formula: Step 2: When oxygen is detected in the production well, the nitrogen content is increased and the air content is reduced by the following formula: Step 3: When the temperature is detected to be too low, increase the air content and hydrocarbon gas content to achieve combustion support by the following formula: Among them, A new is the adjusted air flow, A1 is the current air flow, N new is the adjusted nitrogen flow rate, N1 is the current nitrogen flow rate, T1 is the current bottom hole temperature, T2 is the ideal bottom hole temperature, T3 is the maximum allowable bottom hole temperature, T4 is the minimum allowable bottom hole temperature, N2 is the maximum nitrogen flow rate, O1 is the monitored oxygen content, O2 is the maximum allowable oxygen content, H new is the adjusted hydrocarbon gas flow rate, H1 is the current hydrocarbon gas flow rate, A2 is the maximum air flow rate, and H2 is the maximum hydrocarbon gas flow rate.

5. The real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process according to claim 1, characterized in that: The gas mixer (7) is a static mixer, which is used to mix the gases before entering the air compressor (8).

6. The real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process according to claim 4, characterized in that: The control system also includes a storage module for storing information received by the signal receiving module and information processed by the signal processing module.

7. The real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process according to claim 6 is characterized in that: The control system further comprises a transmission module for performing wired / wireless transmission of the information received by the signal receiving module and the information processed by the signal processing module.

8. The real-time monitoring and dynamic adjustment device for air thermochemical oil recovery process according to claim 7, characterized in that: The storage module is connected to the transmission module through the analysis module. The analysis module is used to analyze the storage data of the storage module and generate logs. The transmission module is used to perform wired / wireless transmission of the logs generated by the analysis module.

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