WO2024060415A1 - Asynchronous cycle-based oil extraction apparatus, method and system - Google Patents

Abstract

Disclosed in the present invention are an asynchronous cycle-based oil extraction apparatus, method and system. The apparatus comprises at least one well group and a control unit; each well group comprises a shaft and at least one horizontal well group; each horizontal well group at least comprises a first well and a second well; the shaft is perpendicular to the ground; the well groups share one shaft; the first well and the second well are both horizontal wells parallel to the ground; a sleeve, an oil pipe and a packer are provided in the shaft; and the control unit is used for performing the following steps on the well group: injecting a gas into the first well by means of the sleeve, and soaking the second well; continuously injecting the gas into the first well so that crude oil displaces to the second well, and performing production in the second well by means of the oil pipe; soaking the first well and the second well, such that the gas enters a low-permeability area; and continuously soaking the first well, and performing production in the second well by means of the oil pipe. The present invention improves the oil extraction efficiency of a heterogeneous oil reservoir having a crack or a high-permeability strip.

Description

Asynchronous cycle-based oil production device, method and system Technical field

The present invention relates to the technical field of oil and gas field development, and in particular to an asynchronous cycle-based oil production device, method and system.

Background technique

Unconventional oil reservoirs such as shale oil and tight oil are rich in resources and are new areas for future oil strategic succession. Due to the poor reservoir properties of unconventional oil reservoirs such as shale oil and tight oil, the matrix permeability is ≤1mD (overburden permeability ≤0.1mD), and the current main method is to develop through depletion after multi-stage fracturing of horizontal wells, but the recovery rate is low and the decline is large. After large-scale fracturing, there are multi-scale fractures, including natural bedding fractures and artificial fracture fractures. During water injection development, water channeling is serious in areas with fractures, and it is difficult for water injection to enter the dense matrix and mobilize crude oil. It is urgent to overcome efficient development technology and technology to significantly increase recovery rate. In addition, key technologies are also urgently needed to significantly increase recovery rates in complex types of reservoirs such as low permeability reservoirs, fault block reservoirs, heavy oil reservoirs and carbonate reservoirs.

Gas injection development is an important technology for improving oil recovery, mainly by injecting gas into the formation to displace oil. Gas types mainly include hydrocarbon gases and non-hydrocarbon gases. Hydrocarbon gases mainly include liquefied petroleum gas, rich gas, dry gas (methane), etc. Non-hydrocarbon gases mainly include CO ₂ , N ₂ , air, flue gas, etc.

From the perspective of oil displacement mechanism, compared with water injection, gas molecules are smaller and can more easily enter the pores of reservoir rocks, making it easier to establish an effective displacement system to drive crude oil. At the same time, after gas injection, it becomes miscible with crude oil or reduces multi-phase interfacial tension and expansion. It has significant effects on crude oil and reducing the viscosity of crude oil, and has a completely different oil displacement mechanism from water. From the perspective of gas injection methods, gas injection huff and puff, continuous gas displacement, water and gas alternation, etc. are currently the main gas injection development methods.

However, due to the strong fluidity of gas, gas channeling easily occurs in the formation, and the fractures in the reservoir and the heterogeneity of the reservoir intensify the gas channeling. These greatly reduce the development effect and limit the application of gas injection technology in different types of oil. Application and promotion in reservoirs, especially for unconventional oil reservoirs and low permeability oil reservoirs such as shale oil and tight oil. Fractures formed by large-scale fracturing have led to very serious gas channeling, which has led to the innovation of gas injection methods. become an urgent problem to be solved.

Contents of the invention

The object of the present invention is to provide an asynchronous cycle oil production device, method and system, which improves the oil production efficiency of heterogeneous oil reservoirs with fractures or high permeability strips.

In order to solve the above technical problems, the present invention provides an oil production device based on an asynchronous cycle. The oil production device includes: at least one well group and a control unit. The well group includes a wellbore and at least one horizontal well group. Each of the The horizontal well group at least includes a first well and a second well, the wellbore is vertical to the ground, each well group shares one wellbore, the first well and the second well are both horizontal wells parallel to the ground; A casing, an oil pipe and a packer are provided in the wellbore. The casing is used for gas injection in the first well, the oil pipe is used for crude oil production in the second well, and the packer is used to isolate the the annular space between the oil pipe and the casing; the control unit is used to perform the following steps on the well group: Step 1: Inject gas into the first well through the casing, and the second The well is simmered; Step 2: Continue to inject the gas into the first well to displace crude oil to the second well, and at the same time, the second well produces through the oil pipe; Step 3: Inject the The first well and the second well are simmered to allow the gas to enter the low permeability area; step 4: continue to simmer the first well, and the second well produces through the oil pipe.

Preferably, the control unit is also used to obtain environmental parameters of the well group in real time to control oil production parameters.

Preferably, the control device is also used to determine the formation pressure and the minimum miscible pressure of the formation fluid based on the environmental parameters, and to control the oil production parameters based on the formation pressure and the minimum miscible pressure of the formation fluid.

Preferably, the environmental parameters include at least: the bottom hole pressure and wellbore pressure of the first well, the bottom hole pressure and wellbore pressure of the second well; the oil production parameters at least include injection pressure, the injection rate of the gas, the Gas injection time, well simmering time, production time and production speed.

Preferably, the control unit is also configured to perform the following steps: in step 1, when the formation pressure is higher than the preset first target pressure, perform step 2; in step 2, when the local pressure is higher than the preset first target pressure, When the formation pressure is lower than the preset second target pressure, step 3 is performed; in step 3, when the derivative of the average formation pressure is zero, step 4 is performed.

Preferably, the first target pressure is 1.4 times the minimum miscible pressure; the second target pressure is 1.2 times the minimum miscible pressure.

Preferably, the control unit is also configured to increase the injection rate and/or the production rate when it is detected that the formation pressure and the minimum miscible pressure of the formation fluid are both less than the pressure target. When the formation pressure and the minimum miscible pressure of the formation fluid are both greater than the pressure target, the injection rate and/or the production rate are reduced.

Preferably, the control unit is also configured to repeatedly execute step 1 to step 4 in sequence, and obtain the oil-gas ratio of the crude oil in real time. When the oil-gas ratio is lower than a preset threshold, the asynchronous periodic oil production is completed. .

Preferably, the control unit includes: a sensor for collecting environmental information of the well group in real time; a calculator for calculating the formation pressure, the minimum miscible pressure of the formation fluid and the average formation pressure according to the environmental information. The derivative of pressure; a controller used to control the oil production parameters and execute the oil production mode formed by step 1 to step 4.

Preferably, the well group includes multiple horizontal well groups, and the angle between two adjacent horizontal well groups is 90°-180°.

Preferably, the first well and the second well of the same horizontal well group are arranged in parallel along the longitudinal direction of the wellbore, and the distance between the first well and the second well is twice the half height of a single well fracture. .

Preferably, the gas is hydrocarbon gas and/or non-hydrocarbon gas, wherein the hydrocarbon gas is at least one of liquefied petroleum gas, rich gas and dry gas, and the non-hydrocarbon gas is at least one of CO ₂ , N ₂ , air and flue gas.

Preferably, a chemical agent for inhibiting gas channeling is added to the gas, and the chemical agent is foam or gel.

Preferably, the oil area to be produced is an unconventional oil reservoir or a conventional oil reservoir, wherein the unconventional oil reservoir is selected from shale oil and tight oil, and the conventional oil reservoir is selected from low permeability oil reservoirs and fault block oil. At least one of a heavy oil reservoir, a heavy oil reservoir and a carbonate reservoir.

Preferably, the first wells of the plurality of horizontal well groups operate asynchronously, and/or the second wells of the plurality of horizontal well groups operate asynchronously.

On the other hand, the present invention also provides an oil recovery method based on asynchronous cycles, which is implemented according to the oil recovery device as described above, wherein the oil recovery method includes: Step 1: Set at least A well group, the well group includes a wellbore and at least one horizontal well group, each horizontal well group includes at least a first well and a second well, the wellbore is vertical to the ground, and each well group shares one wellbore , the first well and the second well are both horizontal wells parallel to the ground, and the wellbore is provided with a casing for gas injection in the first well and an oil pipe for crude oil production in the second well. and a packer for isolating the annular space between the oil pipe and the casing; Step 2: Inject gas into the first well through the casing, and perform well boiling in the second well; Step 3 : Continue to inject the gas into the first well to displace crude oil to the second well, while the second well produces through the oil pipe; Step 4: Inject the first well and the third well The second well is simmered to allow the gas to enter the low permeability area; step 5: continue to simmer the first well, and the second well is produced through the oil pipe.

Preferably, the oil recovery method further includes: repeatedly executing steps 2 to 5 in sequence, and obtaining the oil-gas ratio of the crude oil in real time. When the oil-gas ratio is lower than a preset threshold, the asynchronous periodic oil recovery is completed. .

Preferably, the well group includes multiple horizontal well groups, and the angle between two adjacent horizontal well groups is 90°-180°.

Preferably, the first well and the second well of the same horizontal well group are arranged in parallel along the longitudinal direction of the wellbore, and the distance between the first well and the second well is twice the half height of a single well fracture. .

Preferably, the gas is a hydrocarbon gas and/or a non-hydrocarbon gas, wherein the hydrocarbon gas is at least one of liquefied petroleum gas, rich gas, and dry gas, and the non-hydrocarbon gas is CO ₂ , N ₂ , at least one of air and flue gas.

Preferably, a chemical agent for inhibiting gas channeling is added to the gas, and the chemical agent is foam or gel.

Preferably, the oil area to be produced is an unconventional oil reservoir or a conventional oil reservoir, wherein the unconventional oil reservoir is selected from shale oil and tight oil, and the conventional oil reservoir is selected from low permeability oil reservoirs and fault block oil. At least one of a heavy oil reservoir, a heavy oil reservoir and a carbonate reservoir.

Preferably, the first wells of the plurality of horizontal well groups operate asynchronously, and/or the second wells of the plurality of horizontal well groups operate asynchronously.

In addition, the present invention provides an asynchronous cycle-based oil production system, which includes: the asynchronous cycle-based oil production device as described above; and a gas recovery device for realizing the control of outflow from the well group. gas separation and recovery.

Compared with the existing technology, one or more embodiments of the above solutions may have the following advantages or beneficial effects:

The control unit performs the following four steps on the well group: Step 1: Inject gas into the first well through the casing, and the second well is soaked; Step 2: Continue to inject gas into the first well to drive Transfer crude oil to the second well, and at the same time, the second well produces through oil pipes; Step 3: The first well and the second well are simmered to allow the gas to enter the low permeability area; Step 4: The first well continues to simmer, and the second well produces through tubing.

Since during the execution of step 1 and step 4, only step 1 and step 2 inject gas into the first well, that is, between other two adjacent steps, for example, between step 2 and step 3, there is no operation of injecting gas into the first well; thus, the mechanisms of pressurized mixed phase production of crude oil, displacement of crude oil, well diffusio n, expansion production of crude oil, and depressurized dissolved gas driving crude oil are brought into play, breaking through the technical bottleneck _{of CO2} injection to develop unconventional oil reservoirs such as shale oil and tight oil, and realizing efficient gas injection development of heterogeneous oil reservoirs with fractures or high permeability bands.

In addition, among the four processes in a single cycle, only the first process and the second process inject gas from the injection well, and the remaining two injection processes do not require gas injection, so that less injected gas can be used to achieve better results. Good oil production results effectively improve the oil-gas ratio and economy; and the low-cost three-dimensional development injection-production well model of the present invention deploys two horizontal wells vertically and shares the vertical section wellbore, which can effectively reduce the cost of single-well drilling. , using casing gas injection and oil pipe production, the injection and production of two horizontal wells are integrated, improving the oil displacement efficiency.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and obtained by the structure particularly pointed out in the written description, claims and appended drawings.

Description of the drawings

The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the present invention and do not constitute a limitation of the present invention. In the attached picture:

Figure 1 is an application example diagram of an asynchronous cycle-based oil production device according to an embodiment of the present application.

FIG. 2 is a schematic top view of a first example of an asynchronous cycle-based oil production device according to the embodiment of the present application.

Figure 3 is a schematic top view of a second example of an asynchronous cycle-based oil production device according to the embodiment of the present application.

Figure 4 is a schematic flowchart of the asynchronous cycle-based oil production method according to the embodiment of the present application.

Figure 5 is a schematic diagram of the periodic recovery rate in the asynchronous period-based oil recovery method according to the embodiment of the present application.

Detailed ways

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings and examples, so that the implementation process of how to apply technical means to solve technical problems and achieve technical effects of the present invention can be fully understood and implemented accordingly. It should be noted that as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the resulting technical solutions are within the protection scope of the present invention.

Additionally, the steps illustrated in the flowcharts of the figures may be performed in a computer system, such as a set of computer-executable instructions. Also, although a logical order is shown in the flowchart diagrams, in some cases the steps shown or described may be performed in a different order than herein.

Unconventional oil reservoirs such as shale oil and tight oil are rich in resources and will be a new area for future petroleum strategic succession. Due to poor physical properties of unconventional oil reservoirs such as shale oil and tight oil, with matrix permeability ≤1mD (overburden permeability ≤0.1mD), horizontal wells are currently mainly developed using multi-stage fracturing followed by depletion, but the recovery rate is low. , the decrease is large. After large-scale fracturing, multi-scale fractures exist, including natural bedding fractures and artificial fracturing fractures. During water injection development, water channeling is severe in areas with fractures, making it difficult for water injection to enter the tight matrix and utilize crude oil. There is an urgent need to overcome high-efficiency development technology and greatly increase oil recovery technology. In addition, key technologies are urgently needed to significantly improve oil recovery in complex types of reservoirs such as low permeability reservoirs, fault block reservoirs, heavy oil reservoirs and carbonate reservoirs.

Gas injection development is an important technology for improving oil recovery in oil fields. It mainly injects gas into the formation to drive oil. Gas types mainly include hydrocarbon gas and non-hydrocarbon gas. Hydrocarbon gas mainly includes liquefied petroleum gas, rich gas, dry gas (methane), etc. Non-hydrocarbon gas mainly includes CO2, N2, air, flue gas, etc.

From the perspective of oil displacement mechanism, compared with water injection, gas molecules are smaller and can more easily enter the pores of reservoir rocks, making it easier to establish an effective displacement system to drive crude oil. At the same time, after gas injection, it becomes miscible with crude oil or reduces multi-phase interfacial tension and expansion. It has significant effects on crude oil and reducing the viscosity of crude oil, and has a completely different oil displacement mechanism from water. From the perspective of gas injection methods, gas injection huff and puff, continuous gas displacement, water and gas alternation, etc. are currently the main gas injection development methods.

However, due to the strong fluidity of gas, gas channeling easily occurs in the formation, and the fractures in the reservoir and the heterogeneity of the reservoir intensify the gas channeling. These greatly reduce the development effect and limit the application of gas injection technology in different types of oil. Application and promotion in reservoirs, especially for unconventional oil reservoirs and low permeability oil reservoirs such as shale oil and tight oil. Fractures formed by large-scale fracturing have led to very serious gas channeling, which has led to the innovation of gas injection methods. become an urgent problem to be solved.

The invention provides an oil production device based on asynchronous cycles. The oil production device includes: at least one well group and a control unit. Each well group includes a wellbore and at least one horizontal well group, and each horizontal well group includes at least a first well and a second well. The wellbore is vertical to the ground, and each well group shares one wellbore. The first well and the second well are both horizontal wells parallel to the ground. The wellbore is provided with casing, oil pipe and packer. The casing is used for gas injection in the first well, the oil pipe is used for crude oil production in the second well, and the packer is used for isolation. The annular space of the tubing and casing. Specifically, the packer is used to seal the annular space between the oil pipe and casing of the wellbore to ensure that the gas injected from the casing enters the horizontal well section of the first well. The control unit is used to perform the following operations on the well group: Step 1: Inject gas into the first well through the casing, and perform simmering on the second well; Step 2: Continue to inject gas into the The first well is used to displace crude oil to the second well, while the second well produces through oil pipes; Step 3: Stew the first well and the second well to allow the gas to enter the low Penetration area; Step 4: The first well continues to simmer, and the second well produces through tubing. Wherein, during the execution of steps 1 and 4, only the steps 1 and 2 inject gas into the first well. That is, between other two adjacent steps, for example, between step 2 and step 3, there is no operation of injecting gas into the first well.

Optionally, the control device is also configured to repeatedly execute steps 2 to 4 in sequence, and obtain the oil-gas ratio of the crude oil in real time. When the oil-gas ratio is lower than a preset threshold, the asynchronous periodic oil production task is completed.

This invention can effectively reduce the drilling cost of a single well by vertically deploying two horizontal wells: the first well and the second well, and the two wells share the vertical section wellbore. The horizontal sections of the two wells are parallel, and staged fracturing is implemented. The vertical distance is twice the height of the single-well fracturing half-fracture to ensure control of more reserves and maximize single-well EUR (Estimated Ultimate Recovery).

Step 1: Inject gas into the first well through the casing, and perform simmering in the second well; the injected gas may be hydrocarbon gas and/or non-hydrocarbon gas, and the hydrocarbon gas may be liquefied petroleum gas, Rich gas, dry gas, etc., and the non-hydrocarbon gases are CO ₂ , N ₂ , air, flue gas, etc. The specific location and connection status of the first well and the second well are determined based on the stratigraphic conditions of the specific oil production area. In step 1, the main purpose of stewing the second well is to prevent the injected gas from being produced through the second well, so that the injected gas remains in the reservoir and increases the pressure of the reservoir. At this time, the gas Continue to spread into the reservoir pores. This step 1 can increase the pressure of the entire formation. The increase in pressure can realize the miscibility of the injected gas and the formation crude oil, while reducing the stress sensitivity of the reservoir and improving the seepage capacity and oil displacement efficiency. The casing is made of different grades of steel according to different strengths.

Step 2: Continue to inject gas into the first well to displace crude oil to the second well, and at the same time, the second well produces through the oil pipe; according to a preferred embodiment. Producing the second well includes extracting the crude oil in the second well and outputting it for collection. The oil production operation is performed in the same manner as the gas injection operation of the first well. This step 2 can establish effective displacement between wells, exert the displacing effect of gas between wells, efficiently displace crude oil in fractures or high permeability channels, quickly extract crude oil from easy-flow areas, and at the same time increase the injection rate of gas. The contact area with the matrix or low permeability area effectively improves the utilization rate of crude oil in the matrix or low permeability area. The casing is made of different grades of steel according to different strengths.

Step 3: Stew the first well and the second well to allow the gas to enter the low permeability area. This step 3 mainly exerts the diffusion effect of gas during the well stewing process. The gas enters the crude oil through diffusion, expands the crude oil, and reduces the multi-phase interfacial tension and crude oil viscosity. Since it is a well stewing process, step 3 can weaken the channeling effect of gas, realize the diffusion of gas into the matrix or low permeability area, exert the mechanism of expansion, reduce interfacial tension, and reduce the viscosity of crude oil, and effectively utilize the matrix and low permeability area. of crude oil.

Step 4: The first well continues to simmer, and the second well produces through tubing. In step 4, the first well is continued to be simmered because when the first well is in a closed state, no gas will be injected and produced from the first well, so that part of the gas near the first well It continues to spread into the pores of the reservoir, while the other part flows and displaces towards the second well. This step 4 is used for the gas to displace the remaining crude oil to the second well. Through depressurization depletion development of production wells, the mechanism of solution gas flooding can be fully utilized to achieve efficient development of remaining oil in the matrix, low permeability areas and between wells. At the same time, this process does not require gas injection, which can save injection costs and increase the oil-gas ratio. Improve economy.

During the execution of step 1 and step 4, only step 1 and step 2 inject gas into the first well.

During the execution of the above steps, when the formation pressure in step 1 is higher than the preset first target pressure, step 2 is executed; when the formation pressure in step 2 is lower than the preset second target pressure, step 2 is executed. 3; When the derivative of the average formation pressure in step 3 is zero, perform step 4. The first target pressure is 1.4 times the minimum miscible pressure; the second target pressure is 1.2 times the minimum miscible pressure.

Performing steps 1 to 4 in sequence constitutes one oil production cycle. When multiple oil production cycles are executed, the injection wells and production wells in adjacent oil production cycles can be interchanged. For example, in the first oil production cycle, the first well is the injection well and the second well is the production well. In the second oil production cycle, the first well can be changed to the production well and the second well is the injection well.

The entire development and production process can keep the injection wells of all well groups synchronized, and the production wells of all well groups also synchronized; several well groups can also be combined into a large well group, and the wells in the combined large well group can be synchronized, or The well group performs asynchronous cycle injection and production development in sequential, reverse or irregular order. Preferably, the first wells of the plurality of horizontal well groups operate asynchronously, and/or the second wells of the plurality of horizontal well groups operate asynchronously.

In the process of asynchronous periodic injection and production, according to the gas channeling situation of the production well, chemical agents for inhibiting gas channeling can be added during the injection process of the injection well. The chemical agent can be a foam system, a gel system or other substances that can effectively inhibit gas channeling. Channeling system. In the injection process of the injection well in a single cycle, methods such as alternating gas and water can also be used to effectively suppress gas channeling.

Furthermore, the oil area to be produced is an unconventional oil reservoir or a conventional oil reservoir. Wherein, the unconventional oil reservoir is selected from shale oil and tight oil, and the conventional oil reservoir is selected from at least one of low permeability oil reservoir, fault block oil reservoir, heavy oil oil reservoir and carbonate rock oil reservoir. .

In each process within a single cycle, key parameters such as gas injection pressure, injection speed, injection time, well soaking time, production time, and production speed are optimized using indoor physical simulation or numerical simulation.

Among the four processes in the single cycle, only the first process and the second process inject gas from the injection well, and the remaining two injection processes do not require gas injection, so that less injected gas can be used to achieve better results. The oil recovery effect effectively improves the oil-gas ratio and economy.

The control unit is also used to obtain the environmental parameters of the well group in real time to control the oil production parameters. Specifically, the formation pressure and the minimum miscible pressure of the formation fluid are determined according to the environmental parameters, and then the oil production parameters are controlled according to the formation pressure and the minimum miscible pressure of the formation fluid. For example, when the average formation pressure is lower than the minimum miscible pressure, the injection volume is controlled in real time with 1.4MMP as the target pressure, and the injection speed is designed to be no higher than 90% of the maximum injection speed of the injection pump. When the average formation pressure is higher than 1.4MMP, the first process is skipped and the second process is directly entered.

The environmental parameters at least include: the bottom hole pressure and wellbore pressure of the first well, the bottom hole pressure and wellbore pressure of the second well; the oil production parameters at least include injection pressure, gas injection rate, gas injection duration, well soaking Duration, production time and production speed. The first well and the second well of the same horizontal well group are arranged in parallel along the longitudinal direction of the wellbore, and the distance between the first well and the second well is twice the half height of a single well fracture.

According to a specific implementation, as shown in Figure 1, two horizontal wells are deployed vertically: the injection well m and the production well n. The two wells share the vertical section of the wellbore. The two horizontal wells can use depletion development in the initial stage, or they can directly enter asynchronous development. Periodic injection and production development stage. If depletion development is adopted, the first well produces from the annular space of tubing j and casing i, and the second well produces from tubing j.

During asynchronous period injection and production development, the first well is used as the injection well m, and the second well is used as the production well n. In the vertical section of the wellbore, a packer k is used to seal the annular space of the tubing and casing. When the injection starts, _CO2 is injected from the injection end c of the wellhead Christmas tree into the annular space of the tubing and casing, and enters the horizontal section of the injection well m; when the production well n is in production, the produced fluid flows into the tubing of the production well n, from the wellhead The production nozzle b of the Christmas tree is extracted.

Specifically, it includes: during the CO ₂ asynchronous cycle injection and production process, automatic control is carried out through the control unit a of the intelligent injection and production of the wellhead Christmas tree. The control unit a includes sensors, calculators and controllers. Wherein, the sensor is used to collect environmental information of the well group in real time; the calculator is used to calculate the formation pressure, the minimum miscible pressure of the formation fluid and the derivative of the average formation pressure based on the collected environmental information; the controller is used to control oil production parameters, and execute the oil production method formed by steps 1 to 4 above. Further, the sensor is used to collect the second pressure gauge f, the first pressure gauge d of the casing at the wellhead, the oil pipe gas composition analysis system e, the third pressure gauge f of the injection well m, and the fourth pressure gauge h of the production well n. real-time data; the calculator is used to collect bottom hole pressure gauge data in real time, and calculate the average formation pressure in real time through a built-in mathematical model; and, based on the collected oil pipe gas composition, use the original formation fluid composition to subtract the oil pipe produced gas composition , obtain the current formation fluid composition, and then calculate the corresponding molecular weight through the current formation fluid composition, and further use the following data model to calculate the minimum miscible pressure (MMP) of the formation fluid in real time: MMP=[(7.727×MW×1.005 ^T )-4.377 ×MW-329]/145, where MW is the molecular weight and T is the reservoir temperature. Furthermore, the calculator is used to calculate the derivative of mean formation pressure in real time.

In addition, the controller is also used to optimize the injection rate and production rate using built-in model calculations based on the minimum miscible pressure (MMP) of the formation fluid calculated in real time and combined with the pressure target. For example: when the minimum miscible pressure of the formation fluid and the formation pressure are both less than the pressure target, then increase the injection rate and/or production rate; when the minimum miscibility pressure of the formation fluid and the formation pressure are both greater than the pressure target, then Reduce injection speed and/or production speed.

Furthermore, in accordance with the requirements of the asynchronous cycle injection and production development mode, the controller controls the injection pump, the injection port c of the wellhead Christmas tree and the production nozzle b of the wellhead Christmas tree in real time to perform intelligent injection and production control and achieve efficient development of the reservoir.

In addition, preferably, each well group may include multiple horizontal well groups, and the angle between two adjacent horizontal well groups is 90°-180°. FIG. 2 is a schematic top view of a first example of an asynchronous cycle-based oil production device according to the embodiment of the present application. Figure 3 is a schematic top view of a second example of an asynchronous cycle-based oil production device according to the embodiment of the present application. As shown in Figure 2, it is a top view of a well group in an oil production device. The well group includes a first wellbore 300, a first horizontal well group 301, a second horizontal well group 302, a third horizontal well group 303 and a fourth Horizontal well groups 304, each horizontal well group only includes a first well and a second well, and the angle between two adjacent horizontal well groups is 90 degrees. As shown in Figure 3, the well group includes a second wellbore 400, a fifth horizontal well group 401 and a sixth horizontal well group 402. The angle between two adjacent horizontal well groups is 180 degrees.

The asynchronous periodic oil production device of the present invention realizes efficient, automatic and intelligent control, and designs a low-cost three-dimensional development injection and production well model for the asynchronous periodic gas injection and oil production method.

The oil production device also exerts the mechanisms of pressurizing miscible crude oil, displacing crude oil, well diffusion, expanding crude oil, and depressurizing dissolved gas to drive crude oil. The oil displacement efficiency exceeds 90%, breaking through the _CO2 injection to develop shale oil, The technical bottleneck of unconventional reservoirs such as tight oil has achieved efficient development of gas injection in heterogeneous reservoirs with fractures or high permeability strips; among the four processes in a single cycle, only the first and second processes Gas is injected from the injection well, and there is no need to inject gas in the other two injection processes. In this way, better oil recovery results can be achieved with less injected gas, effectively improving the oil-gas ratio and economy; and the low-cost three-dimensional structure of the present invention The injection and production well model is developed, and two horizontal wells are deployed vertically. The two wells share the vertical section of the wellbore, which can effectively reduce the drilling cost of a single well. The injection and production of two horizontal wells are integrated by using casing gas injection and tubing production, which improves the efficiency of the injection and production wells. Efficiency; the present invention also integrates sensors, calculators, and controllers on the production tree through intelligent control to achieve real-time calculation and precise control of average formation pressure, minimum miscible pressure of formation fluid, target formation pressure, injection rate, and production rate.

Based on the above-mentioned oil production device based on asynchronous cycle, the present invention also proposes an oil production method based on asynchronous cycle. The oil production method is implemented according to the above-mentioned asynchronous period-based oil production device. This oil production method is mainly used in unconventional resources such as shale oil and tight oil, low permeability reservoirs, heavy oil reservoirs, integrated reservoirs, fault block reservoirs, high water content reservoirs, high temperature and high salt reservoirs, carbonic acid reservoirs, etc. Development of salt rock reservoirs and other special lithology reservoirs.

Figure 4 is a schematic flowchart of the asynchronous cycle-based oil production method according to the embodiment of the present application. As shown in Figure 4, step S101 is: setting up at least one well group in the oil production area, each well group includes a wellbore and at least one horizontal well group, and each horizontal well group includes at least a first well and a second well, The wellbore is perpendicular to the ground, and each well group shares one wellbore. The first well and the second well are both horizontal wells parallel to the ground. Wherein, the first well may be an injection well, and the second well may be a production well. Each well group may include multiple first wells and multiple second wells, and the first well and the second well may include The injection and production methods can be different, and the injection and production cycles can be asynchronous. The first well and the second well of the same horizontal well group are arranged in parallel along the longitudinal direction of the wellbore, and the distance between the first well and the second well is twice the half height of a single well fracture. Each well group may include multiple horizontal well groups. Preferably, the angle between two adjacent horizontal well groups is 180°.

The wellbore is provided with casing, oil pipe and packer. The casing is used for gas injection of the first well, the oil pipe is used for crude oil production of the second well, and the packer is used for isolation. The tubing and casing.

This invention can effectively reduce the drilling cost of a single well by vertically deploying two horizontal wells: the first well and the second well, and the two wells share the vertical section wellbore. The horizontal sections of the two wells are parallel, and staged fracturing is implemented. The vertical distance is twice the height of the single-well fracturing half-fracture to ensure control of more reserves and maximize single-well EUR (Estimated Ultimate Recovery).

Step S102 is: injecting gas into the first well through the casing, and performing well boiling on the second well. The injected gas can be hydrocarbon gas and/or non-hydrocarbon gas. The hydrocarbon gas is liquefied petroleum gas, rich gas, dry gas, etc., and the non-hydrocarbon gas is CO ₂ , N ₂ , air, flue Qi and so on. The specific location and connection status of the first well and the second well are determined based on the stratigraphic conditions of the specific oil production area.

This step S102 can increase the pressure of the entire formation. The increase in pressure can achieve miscibility of the injected gas and the formation crude oil, while reducing reservoir stress sensitivity and improving seepage capacity and oil recovery efficiency.

Step S103 is: continuing to inject gas into the first well to displace crude oil to the second well, while the second well produces through the oil pipe. According to a preferred embodiment. Producing the second well includes extracting crude oil in the second well and exporting it for collection.

This step S103 can establish effective displacement between wells, exert the displacing effect of gas between wells, efficiently displace crude oil in fractures or high permeability channels, quickly extract crude oil from easy-flow areas, and at the same time increase the injection rate of gas. The contact area with the matrix or low permeability area effectively improves the utilization rate of crude oil in the matrix or low permeability area.

Step S104 is: the first well and the second well are soaked to allow the gas to enter the low permeability area. This step mainly plays the role of gas diffusion during the soaking process. The gas diffuses into the crude oil, expands the crude oil, and reduces the multiphase interface tension and crude oil viscosity. Since it is a soaking process, this step can weaken the cross-flow effect of the gas, realize the diffusion of the gas into the matrix or low permeability area, play the role of expansion, reduce the interface tension, and reduce the viscosity of the crude oil, and efficiently mobilize the crude oil in the matrix and low permeability area.

Step S105 is: the first well continues to simmer, and the second well produces through oil pipes. This step S105 is used for the gas to displace the remaining crude oil to the second well. Through depressurization depletion development of production wells, the mechanism of solution gas flooding can be fully utilized to achieve efficient development of remaining oil in the matrix, low permeability areas and between wells. At the same time, this process does not require gas injection, which can save injection costs and increase the oil-gas ratio. Improve economy.

During the execution of steps 102 and 105, only steps 102 and 103 are used to inject gas into the first well. Between other adjacent steps, for example, between steps 103 and 104, no gas is injected into the first well. The operation of injecting gas into a well.

During the execution of the above steps, when the formation pressure in step 102 is higher than the preset first target pressure, step 103 is executed; when the formation pressure in step 103 is lower than the preset second target pressure, step 104 is executed; when the derivative of the average formation pressure in step 104 is zero, step 105 is executed.

Executing steps S101 to S105 in sequence constitutes one oil production cycle. When multiple oil production cycles are executed, the injection wells and production wells in adjacent oil production cycles can be interchanged. For example, in the first oil production cycle, the first well is the injection well and the second well is the production well. In the second oil production cycle, the first well can be changed to the production well and the second well is the injection well.

The entire development and production process can keep the injection wells of all well groups synchronized, and the production wells of all well groups also synchronized; several well groups can also be combined into a large well group, and the wells in the combined large well group can be synchronized, or The well group performs asynchronous cycle injection and production development in sequential, reverse or irregular order. Preferably, the first wells of the plurality of horizontal well groups operate asynchronously, and/or the second wells of the plurality of horizontal well groups operate asynchronously.

During the asynchronous periodic injection and production process, according to the gas channeling situation of the production well, chemical agents can be added to inhibit gas channeling during the injection process of the injection well. The chemical agent can be a foam system, a gel system, or other systems that can effectively inhibit gas channeling. In the injection process of the injection well in a single cycle, methods such as alternating gas and water can also be used to effectively suppress gas channeling.

In each process within a single cycle, key parameters such as gas injection pressure, injection speed, injection time, well soaking time, production time, and production speed are optimized using indoor physical simulation or numerical simulation.

Among the four processes in the single cycle, only the first process and the second process inject gas from the injection well, and the remaining two injection processes do not require gas injection, so that less injected gas can be used to achieve better results. The oil recovery effect effectively improves the oil-gas ratio and economy.

The oil production method also includes obtaining environmental parameters of the well group in real time for controlling oil production parameters. Specifically, it includes determining the formation pressure and the minimum miscible pressure of the formation fluid based on environmental parameters; controlling the oil production parameters based on the formation pressure and the minimum miscible pressure of the formation fluid. For example, when the average formation pressure is lower than the minimum miscible pressure, the injection volume is controlled in real time with a target pressure of 1.4MMP, and the injection rate is designed to be no higher than 90% of the maximum injection rate of the injection pump. When the average formation pressure is higher than 1.4MMP, the first process is skipped and the second process is entered directly. The environmental parameters at least include: bottom hole pressure and wellbore pressure of the first well and the second well; the oil production parameters at least include gas injection pressure, gas injection speed, gas injection time, well soaking time, production time and Production speed.

Specifically, it includes: during the CO ₂ asynchronous cycle injection and production process, automatic control is carried out through the control unit a of the intelligent injection and production of the wellhead Christmas tree. The control unit a includes a sensor, a calculator and a controller. The sensor is used to collect real-time data of the second pressure gauge f, the first pressure gauge d of the casing at the wellhead, the oil pipe gas composition analysis system e, the third pressure gauge f of the injection well m, and the fourth pressure gauge h of the production well n. data; the calculator shown is used to collect bottom hole pressure gauge data in real time, and calculates the average formation pressure in real time through the built-in mathematical model; using the collected oil pipe gas composition, subtracting the oil pipe gas composition from the original formation fluid composition, the current formation fluid composition is obtained. The molecular weight is obtained through composition calculation and the following built-in mathematical model: MMP=[(7.727×MW×1.005 ^T )-4.377×MW-329]/145, where MW is the molecular weight and T is the reservoir temperature. Calculate the minimum miscible pressure (MMP) of the formation fluid in real time, and use the built-in model to calculate and optimize the injection rate and production rate according to the pressure target; calculate the derivative of the average formation pressure in real time. In accordance with the requirements of the asynchronous cycle injection and production development method, the controller controls the injection pump, the injection port c of the wellhead Christmas tree and the production nozzle b of the wellhead Christmas tree in real time to perform intelligent injection and production control to achieve efficient development of the reservoir.

For example: Process 1: The sensor of the control unit a of the wellhead Christmas tree intelligent injection and production collects the bottom hole pressure gauge data of two horizontal wells, and its calculator calculates the average of the bottom hole pressure of the two horizontal wells in real time to obtain the average formation pressure, which is calculated as 1.4 times the minimum miscible pressure (MMP) as the target average formation pressure, calculate and optimize the injection rate, and start CO ₂ injection. When the average formation pressure reaches 1.4 times the MMP, the intelligent injection and production control system controls the production nozzle b to open and enter the first Second process. The main purpose of process one is to increase the pressure and achieve miscibility.

Process 2: With the average formation pressure reaching 1.2 times MMP as the target pressure, the intelligent injection-production displacement process is carried out. CO ₂ is injected into the injection well and produced by the production well. The production-injection ratio is set in the calculator of the intelligent injection-production control system, and the production wells are produced according to the production speed results calculated by the intelligent injection-production control system and the constant liquid volume to control the size of the nozzle. The average formation pressure gradually decreases during the entire displacement process. The intelligent injection-production ratio is set in the calculator of the intelligent injection-production control system. The calculator of the injection and production control system calculates the average formation pressure in real time. When the average formation pressure drops to 1.2 times MMP, both the injection well and the production well are closed and enter the next process. The main purpose of process two is to use pressure difference to displace crude oil and gravity to displace crude oil, thereby expanding the spread of CO ₂ in the reservoir.

Process 3: Two horizontal wells are shut in and soaked at the same time. The intelligent injection and production control system determines in real time whether the derivative of the average formation pressure is zero. When it reaches zero, the soaking ends and the next process begins. The main purpose of process 3 is to allow _CO2 to diffuse into the matrix during the soaking process, and the crude oil in the mobilized crude oil and fractures flows to the production well under the action of gravity.

Process 4: The injection well continues to be shut in, and the production well goes into production. The intelligent injection and production control system calculates the real-time average formation pressure. When the average formation pressure drops to 0.8 times MMP, the production well is shut down. The four processes of the first cycle end and enter the next cycle. The main purpose of process four is to displace crude oil by dissolved gas and displace oil by gravity.

Repeat the four processes of the above cycle, and obtain the oil-gas ratio of the crude oil in real time until the oil-gas ratio is lower than the set threshold, then oil production is completed. As long as the output is higher than the economic limit output, production continues, otherwise, the development process stops.

An output CO ₂ separation and recovery device can be added at the wellhead to separate CO ₂ from the output fluid of the production well and reinject it through the injection well, thus achieving separation and reinjection at the same wellhead, recycling CO ₂ and reducing CO ₂ costs.

Example 1:

A certain shale reservoir to be tested is 90 meters thick and is developed in two layers. The horizontal section of the first well in a horizontal well group is 15 meters from the bottom. The horizontal section is 500 meters long. Fracturing is carried out in 10 sections. Microseismic Monitoring shows that the half-fracture of the horizontal well's pressure fracture is 15 meters high. The horizontal section of the second well travels 45 meters from the bottom. The horizontal section is 500 meters long. The fracturing is carried out in 10 sections. Microseismic monitoring shows that the horizontal well's pressure fracture is 15 meters high. The seam height is 15 meters. The horizontal sections of the two horizontal wells are parallel and share the vertical well section. _CO2 is injected from the casing into the upper horizontal well, and crude oil and other produced fluids are produced from the tubing of the lower horizontal well. The wellhead Christmas tree is equipped with an intelligent injection and production control system, which directly uses asynchronous cycles. Developed by injection-mining development method.

The original reservoir pressure is 17MPa, and the original reservoir temperature is 80 degrees Celsius. The experimentally measured minimum miscible pressure of formation crude oil and _CO2 at the reservoir temperature is 20MPa.

Asynchronous cycle injection and mining development steps:

Step 1: The sensors of the intelligent injection and production control system of the wellhead Christmas tree collect the bottom hole pressure of the two horizontal wells to be 17MPa. The average formation pressure at the beginning is 17MPa. The target average formation pressure is 1.4 times the minimum miscible pressure (MMP) of 28MPa. The _CO2 injection is calculated and optimized to start at an injection rate of 60 tons/day. The calculator of the intelligent injection and production control system calculates the average formation pressure in real time. When the average formation pressure reaches 28MPa, the signal is transmitted to the production end of the wellhead Christmas tree, the production nozzle is opened, and the second process begins.

Step 2: With the average formation pressure 1.2 times MMP24MPa as the target pressure, carry out the intelligent injection and production displacement process. Inject CO ₂ into the injection well and maintain the injection rate at 60 tons/day. In the calculator of the intelligent injection and production control system, the injection and production The ratio is set to 1.1, and the production well is produced according to 66 tons/day and the size of the nozzle is controlled by a constant liquid volume. The entire process gradually reduces the average formation pressure. The calculator of the intelligent injection and production control system calculates the average formation pressure in real time. When the average formation pressure When it drops to 24MPa, both the injection well and the production well are closed and the next process is entered.

Step 3: The two horizontal wells are shut in at the same time and the intelligent injection and production control system determines in real time whether the derivative of the average formation pressure is zero. After 30 days of well soaking, the derivative of the average formation pressure reaches zero, and the well soaking is completed and the next process is entered.

Step 4: The injection well continues to be shut in, and the production well produces according to 66 tons/day, constant liquid volume, and controlled nozzle size. The intelligent injection and production control system calculates the real-time average formation pressure. When the average formation pressure drops to 0.8 times MMP16MPa, the production well Close the well. The four processes of the first cycle end and enter the next cycle.

Six cycles are repeated, at which time the oil-to-gas ratio is 0.05 and the development process is stopped.

FIG5 is a schematic diagram of the cycle recovery rate in the asynchronous cycle-based oil recovery method of the embodiment of the present application. As shown in FIG5, after 6 cycles, the recovery rate is as high as 34%, and the effect of significantly improving the recovery rate is clearly seen. From the cycle recovery rate characteristics, as the number of cycles increases, the recovery rate shows a trend of first increasing rapidly and then increasing slowly. Among them, the recovery rate of the first cycle is the largest, reaching 15.5%. The asynchronous cycle oil production method of the present invention brings into play the mechanism of boosting mixed phase to produce crude oil, displacing crude oil, soaking well diffusion, expanding crude oil, gravity oil drainage, and depressurized dissolved gas to drive crude oil, with an oil recovery efficiency of more than 90%, breaking through the technical bottleneck of injecting _CO2 to develop unconventional oil reservoirs such as shale oil and tight oil, and realizing efficient gas injection development of heterogeneous oil reservoirs with fractures or high permeability bands; in the four processes of a single cycle, gas is injected from the injection well only in the first process and the second process, and gas injection is not required in the other two injection processes, so that better oil production effect can be achieved with less injected gas, and the oil-gas ratio and economy are effectively improved; and the low-cost three-dimensional development injection and production well mode of the present invention deploys two horizontal wells in the vertical direction, and the two wells share a vertical section wellbore, which can effectively reduce the drilling cost of a single well, and realizes the integration of injection and production of two horizontal wells by using casing gas injection and oil pipe oil production, thereby improving efficiency; the present invention also integrates sensors, calculators, and controllers on the oil tree through intelligent control, and realizes real-time calculation and precise control of average formation pressure, minimum miscible pressure of formation fluid, target formation pressure, injection speed, and production speed.

On the other hand, the present invention also provides an oil production system based on asynchronous cycles. The oil production system includes the above-mentioned oil production device and gas recovery device. The gas recovery device is used to separate and recover gas flowing out of the well group. When the injection of this oil production system starts, CO ₂ is injected from the injection end c of the wellhead Christmas tree into the annular space of the tubing and casing, and enters the horizontal section of injection well A; when production well B is producing, the produced fluid flows into the horizontal section of horizontal well B The oil pipe is extracted from the production nozzle b of the wellhead Christmas tree. It realizes gas injection and oil production in the same well, realizing a low-cost three-dimensional development injection and production well model.

The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technology can easily think of changes or substitutions within the technical scope disclosed in the present invention. , should all be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

It should be understood that the disclosed embodiments of the present invention are not limited to the specific structures, process steps, or materials disclosed herein, but extend to equivalents of these features as understood by those of ordinary skill in the relevant art. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

Reference in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Therefore, appearances of the phrases "one embodiment" or "an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment.

Although the embodiments disclosed in the present invention are as above, the described contents are only used to facilitate the understanding of the present invention and are not intended to limit the present invention. Any person skilled in the technical field to which the present invention belongs may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed by the present invention. However, the patent protection scope of the present invention shall not The scope defined by the appended claims shall prevail.

Claims (24)

1. An oil production device based on asynchronous cycles, characterized in that the oil production device includes: at least one well group and a control unit,

   The well group includes a wellbore and at least one horizontal well group, each horizontal well group includes at least a first well and a second well, the wellbore is vertical to the ground, each well group shares one wellbore, and the third wellbore is The first well and the second well are both horizontal wells parallel to the ground;

   The wellbore is provided with casing, oil pipe and packer. The casing is used for gas injection of the first well, the oil pipe is used for crude oil production of the second well, and the packer is used for isolation. The annular space between the oil pipe and the casing;

   The control unit is used to execute the following steps on the well group:

   Step 1: Inject gas into the first well through the casing, and perform well boiling in the second well;

   Step 2: Continue to inject the gas into the first well to displace crude oil to the second well, while the second well produces through the oil pipe;

   Step 3: Stew the first well and the second well to allow the gas to enter the low permeability area;

   Step 4: Continue to simmer the first well, and the second well produces through the oil pipe.
2. The oil production device according to claim 1, characterized in that the control unit is also used to obtain environmental parameters of the well group in real time to control oil production parameters.
3. The oil production device according to claim 2, characterized in that:

   The control device is also used to determine the formation pressure and the minimum miscible pressure of the formation fluid according to the environmental parameters, and control the oil production parameters according to the formation pressure and the minimum miscible pressure of the formation fluid.
4. The oil production device according to claim 2 or 3, characterized in that:

   The environmental parameters at least include: the bottom hole pressure and the wellbore pressure of the first well, the bottom hole pressure and the wellbore pressure of the second well;

   The oil production parameters at least include injection pressure, injection rate of the gas, injection time of the gas, well soaking time, production time and production speed.
5. The oil production device according to claim 3 or 4, characterized in that the control unit is also used to perform the following steps:

   In step 1, when the formation pressure is higher than the preset first target pressure, step 2 is executed;

   In step 2, when the formation pressure is lower than the preset second target pressure, step 3 is executed;

   In step 3, when the derivative of the average formation pressure is zero, step 4 is performed.
6. The oil production device according to claim 5, characterized in that:

   The first target pressure is 1.4 times the minimum miscible pressure;

   The second target pressure is 1.2 times the minimum miscible pressure.
7. The oil production device according to any one of claims 4 to 6, characterized in that the control unit is also configured to detect that the formation pressure and the minimum miscible pressure of the formation fluid are both less than the pressure target, Increase the injection rate and/or the production rate, and when it is detected that the formation pressure and the minimum miscible pressure of the formation fluid are both greater than the pressure target, decrease the injection rate and/or the production rate. .
8. The oil production device according to any one of claims 1 to 7, characterized in that the control unit is also configured to repeatedly execute the steps 1 to 4 in sequence and obtain the oil-gas ratio of the crude oil in real time, When the oil-gas ratio is lower than the preset threshold, asynchronous periodic oil production is completed.
9. The oil production device according to any one of claims 2 to 7, characterized in that the control unit includes:

   Sensors used to collect environmental information of the well group in real time;

   A calculator configured to calculate derivatives of the formation pressure, the minimum miscible pressure of the formation fluid, and the average formation pressure based on the environmental information;

   A controller, which is used to control the oil production parameters and execute the oil production mode formed by step 1 to step 4.
10. The oil production device according to any one of claims 1 to 9, characterized in that the well group includes a plurality of horizontal well groups, and the angle between two adjacent horizontal well groups is 90°-180 °.
11. The oil production device according to any one of claims 1-10, characterized in that,

    The first well and the second well of the same horizontal well group are arranged in parallel along the longitudinal direction of the wellbore, and the distance between the first well and the second well is twice the half height of a single well fracture.
12. The oil production device according to any one of claims 1 to 11, characterized in that the gas is hydrocarbon gas and/or non-hydrocarbon gas, wherein the hydrocarbon gas is liquefied petroleum gas, rich gas, At least one of dry gases, and the non-hydrocarbon gas is at least one of CO ₂ , N ₂ , air, and flue gas.
13. The oil production device according to claim 12, characterized in that a chemical agent for inhibiting gas channeling is added to the gas, and the chemical agent is foam or gel.
14. The oil production device according to any one of claims 1 to 13, characterized in that the oil area to be produced is an unconventional oil reservoir or a conventional oil reservoir, wherein the unconventional oil reservoir is selected from the group consisting of shale oil and tight oil reservoirs. Oil, the conventional oil reservoir is selected from at least one of low permeability oil reservoir, fault block oil reservoir, heavy oil oil reservoir and carbonate rock oil reservoir.
15. The oil production device according to any one of claims 1-14, characterized in that,

    The first well of the plurality of horizontal well groups operates asynchronously, and/or the second well of the plurality of horizontal well groups operates asynchronously.
16. An oil production method based on asynchronous cycles, characterized in that the oil production method is implemented according to the oil production device according to any one of claims 1 to 15, wherein the oil production method includes:

    Step 1: Set up at least one well group in the oil to be produced area, the well group includes a wellbore and at least one horizontal well group, each horizontal well group includes at least a first well and a second well, and the wellbore is vertical to the ground, Each well group shares one wellbore, and both the first well and the second well are horizontal wells parallel to the ground. The wellbore is provided with casings for gas injection in the first well, and casings for gas injection in all wellbores. The oil pipe for crude oil production of the second well and the packer used to isolate the annular space between the oil pipe and the casing;

    Step 2: Inject gas into the first well through the casing, and perform well boiling in the second well;

    Step 3: Continue to inject the gas into the first well to displace crude oil into the second well, while the second well produces through the oil pipe;

    Step 4: Stew the first well and the second well to allow the gas to enter the low permeability area;

    Step 5: Continue to simmer the first well, and the second well produces through the oil pipe.
17. The oil production method according to claim 16, characterized in that the oil production method further includes:

    Steps 2 to 5 are repeatedly executed in sequence, and the oil-gas ratio of the crude oil is obtained in real time. When the oil-gas ratio is lower than a preset threshold, asynchronous periodic oil production is completed.
18. The oil production method according to claim 16 or 17, characterized in that the well group includes a plurality of horizontal well groups, and the angle between two adjacent horizontal well groups is 90°-180°.
19. The oil recovery method according to any one of claims 16-18, characterized in that,

    The first well and the second well of the same horizontal well group are arranged in parallel along the longitudinal direction of the wellbore, and the distance between the first well and the second well is twice the half height of a single well fracture.
20. The oil production method according to any one of claims 16 to 19, characterized in that the gas is hydrocarbon gas and/or non-hydrocarbon gas, wherein the hydrocarbon gas is liquefied petroleum gas, rich gas, At least one of dry gases, and the non-hydrocarbon gas is at least one of CO ₂ , N ₂ , air, and flue gas.
21. The oil recovery method according to claim 20, characterized in that a chemical agent for inhibiting gas channeling is added to the gas, and the chemical agent is foam or gel.
22. The oil production method according to any one of claims 16 to 21 is characterized in that the area to be produced is an unconventional oil reservoir or a conventional oil reservoir, wherein the unconventional oil reservoir is selected from shale oil and tight oil, and the conventional oil reservoir is selected from at least one of a low permeability oil reservoir, a fault block oil reservoir, a heavy oil reservoir and a carbonate oil reservoir.
23. The oil recovery method according to any one of claims 16-22, characterized in that,

    A first well of a plurality of horizontal well groups operates asynchronously, and/or a second well of a plurality of horizontal well groups operates asynchronously.
24. An oil production system based on asynchronous cycles, characterized in that the oil production system includes:

    The asynchronous cycle-based oil production device according to any one of claims 1 to 15; and a gas recovery device, which is used to separate and recover gas flowing out of the well group.

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