Apparatus and Method for Evaluating the Online Dynamic Effect of CO2 Huff and Puff in Heavy Oil Fields

Abstract

The application discloses a device and method for evaluating the on-line dynamic effect of CO2 huff and puff in a thickened oil field, the device comprising an injection mechanism, a model mechanism, an oil-water saturation mechanism, a pressure control mechanism, a temperature control mechanism, an output metering and component analysis mechanism, and a data control mechanism, wherein the injection mechanism is used for providing different injection fluids for the model mechanism; the model mechanism is used for simulating CO2 huff and puff of a target reservoir; the oil-water saturation mechanism is used for realizing oil-water saturation of the model mechanism; the pressure control mechanism is used for controlling the pressure of the whole CO2 huff and puff simulation process; the temperature control mechanism is used for controlling the temperature of the whole CO2 huff and puff simulation process; the output metering and component analysis mechanism is used for realizing output metering and on-line detection of oil and gas components in the CO2 huff and puff process; and the data control mechanism is used for collecting temperature, pressure, output and component data of the whole CO2 huff and puff simulation process. The application can simultaneously realize dynamic effect evaluation of CO2 huff and puff and change of output gas and output crude oil components with injection time, and has the advantages of simple operation, convenient method, repeated use of the device, high experimental simulation repetition rate, no interruption in the whole process, and zero carbon emission.

Description

Technical Field

[0001] This invention belongs to the field of petroleum extraction technology, specifically relating to a device and method for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields. Background Technology

[0002] my country possesses substantial and widely distributed heavy oil reserves, but the high viscosity of its crude oil increases the difficulty of extraction. With the continuous improvement of domestic oilfield extraction technology, heavy oil extraction has gradually become a key development focus for various oilfields. CO2, upon contact with formation heavy oil, rapidly dissolves in the crude oil, causing it to expand in volume, reduce viscosity, and improve fluidity. It can also extract and vaporize light hydrocarbons in the crude oil, achieving dissolved gas drive, improving interfacial tension and oil-water mobility ratio, and simultaneously possessing water shut-off, profile control, and acid plugging / unblocking effects. These characteristics all contribute to improving heavy oil recovery. Furthermore, CO2, as the most produced greenhouse gas in China's industrial sector, causes severe air pollution. CO2 huff and puffing in heavy oil fields can not only solve the CO2 sequestration problem, protect the atmospheric environment, and suppress the greenhouse effect, but also meet the needs of oilfield development, significantly improving reservoir recovery. Therefore, CO2 huff and puffing technology in heavy oil fields can both improve crude oil recovery and provide a solution for greenhouse gas consumption, representing an innovative approach to greenhouse gas emission treatment. Evaluation of CO2 huff and puff performance in heavy oil fields determines the potential of this technology and is key to its research and application. This includes research on oil displacement mechanism, huff and puff performance evaluation, huff and puff production component analysis, research on the variation law of production components at different stages of huff and puff, optimization of huff and puff injection and production parameters, determination of huff and puff well shut-in time, huff and puff cycle research, and pressure decay rate and pressure control methods during huff and puff.

[0003] To address the aforementioned research content, the current evaluation of CO2 huff and puff dynamics in heavy oil fields primarily relies on a combination of devices such as core displacement units, high-temperature and high-pressure reactors, gas chromatography, and liquid chromatography. However, these traditional CO2 huff and puff dynamics evaluation devices have the following drawbacks: (1) The sampling and detection of the produced gas is delayed, and there are errors in the sampling and detection; (2) The sampling and testing of produced crude oil is delayed, and there are errors in the sampling and testing. (3) Manual measurement is outdated and prone to errors; (4) The back pressure gradient problem caused by manual back pressure control during the back pressure flow-through process cannot truly simulate the linear decay process of formation pressure; (5) Pressure and temperature were manually controlled throughout the process, resulting in data lag and human error; (6) Unable to provide online feedback; (7) The produced gas is discharged into the atmosphere and cannot be collected; (8) Discontinuous and delayed sampling by human intervention; (9) Discontinuity and lag in operation and control caused by human intervention in the entire process of device operation and control. Summary of the Invention

[0004] This invention is proposed to solve the problems existing in the above-mentioned traditional CO2 huff and puff dynamic effect evaluation technology, and its purpose is to provide an apparatus and method for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields.

[0005] This invention is achieved through the following technical solution: An apparatus for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields, comprising: The injection mechanism provides different injection fluids for the model mechanism; Model structure for simulating target reservoirs with CO2 huff and puff; Oil-water saturation mechanism to achieve oil-water saturation of the model mechanism; Pressure control mechanism, used to control the pressure throughout the CO2 throughput simulation; Temperature control mechanism used to control the temperature throughout the CO2 throughput simulation; The output metering and component analysis unit is used to realize the output metering and online detection of oil and gas components during the CO2 huff and puff process; The data control mechanism is used to collect temperature, pressure, output, and composition data throughout the CO2 throughput simulation.

[0006] In the above technical solution, the injection mechanism includes a CO2 injection mechanism, an oil injection mechanism, and a water injection mechanism, which are respectively connected to the model mechanism, as well as a power source. The CO2 injection mechanism includes a CO2 cylinder and a CO2 intermediate container, which are respectively connected to the model mechanism, and the CO2 intermediate container is connected to the power source. The oil injection mechanism includes an oil intermediate container, one end of which is connected to the model mechanism and the other end of which is connected to the power source. The water injection mechanism includes a water intermediate container, one end of which is connected to the model mechanism and the other end of which is connected to the power source.

[0007] In the above technical solution, a pressure reducing valve, a pressure regulating valve, and valve No. I are sequentially installed on the pipeline between the CO2 cylinder and the model mechanism; the pressure reducing valve is located close to the CO2 cylinder; valve No. IV is installed on the pipeline between the CO2 intermediate container and the model mechanism, and valve No. III is installed on the pipeline between the CO2 intermediate container and the power source.

[0008] In the above technical solution, valve VI is installed on the pipeline between the oil intermediate container and the model mechanism, and valve V is installed on the pipeline between the oil intermediate container and the power source; valve VIII is installed on the pipeline between the water intermediate container and the model mechanism, and valve VII is installed on the pipeline between the water intermediate container and the power source; the power source is an injection pump, and valve II is installed at the output end of the injection pump.

[0009] In the above technical solution, the model mechanism includes a clamp, one end of which is connected to the injection mechanism and the other end of which is connected to the oil-water saturation mechanism. A valve IX is installed on the pipeline between the clamp and the injection mechanism, and a valve XII is installed on the pipeline between the clamp and the oil-water saturation mechanism. A pressure gauge I is installed between the valve IX and the clamp, and a pressure gauge II is installed between the clamp and the valve XII.

[0010] In the above technical solution, the oil-water saturation mechanism includes an oil-water metering pipe and an oil-water monitoring camera located next to the oil-water metering pipe. The oil-water metering pipe is connected to the model mechanism through an oil-water production pipeline.

[0011] In the above technical solution, the pressure control mechanism includes a back pressure pump, a back pressure control mechanism, and a return back pressure control mechanism; the back pressure control mechanism includes a back pressure valve disposed between the model mechanism and the oil-water saturation mechanism, and a No. II buffer container connected to the back pressure valve, the other end of which is connected to the back pressure pump; a No. XIII valve is disposed between the No. II buffer container and the back pressure pump, and a No. XX valve is disposed between the No. II buffer container and the back pressure valve; the return back pressure control mechanism includes a No. II back pressure valve disposed between the injection mechanism and the output metering and component analysis mechanism, the No. II back pressure valve is connected to the back pressure pump, and a No. XIV valve is disposed on the pipeline between the two, and a No. XV valve is disposed on the pipeline between the No. II back pressure valve and the output metering and component analysis mechanism; the pressure control mechanism also includes a No. I buffer container and a confining pressure pump connected to each other, and a No. XI valve is disposed on the pipeline between the two, the No. I buffer container is connected to the clamp, and a No. X valve is disposed on the pipeline between the two.

[0012] In the above technical solution, the output metering and component analysis mechanism includes an oil-gas-water metering pipe, a gas detection mechanism connected to the oil-gas-water metering pipe via a gas output pipeline, and a crude oil detection mechanism connected to the oil-gas-water metering pipe via a crude oil output pipeline; an oil-water monitoring camera is installed beside the oil-gas-water metering pipe; the gas detection mechanism includes a gas component detector and an output gas trap connected to each other, and valves XVII, XIX, and XVII are sequentially installed on the pipeline between the gas component detector and the oil-gas-water metering pipe; the crude oil detection mechanism includes a suction pump, a metering pump, and a crude oil component detector connected in sequence, with valve XVIII between the suction pump and the metering pump, and valve XVI between the suction pump and the oil-gas-water metering pipe; a float is installed at one end of the crude oil output pipeline that extends into the oil-gas-water metering pipe, and the float is suspended between the oil-water interface and the oil-gas interface of the oil-gas-water metering pipe; the oil-gas-water metering pipe is connected to the injection mechanism via interconnected oil-gas-water output pipelines and return fluid transmission pipelines.

[0013] In the above technical solution, the model mechanism, oil-water saturation mechanism, output metering and component analysis mechanism, and pressure control mechanism are all located inside a constant temperature chamber.

[0014] A method for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields includes the following steps: (I) Add CO2 to the intermediate CO2 container to the pressure required for the experiment; (II) Set the temperature of the constant temperature chamber to the experimental temperature, start the confining pressure pump to the experimental confining pressure, and start the return pressure pump to the experimental return pressure; (III) The fluid in the oil-water production pipeline flows into the oil-water metering pipe, and the clamp is aged in a constant temperature chamber; (IV) Inject CO2 into the clamp and age the clamp in a constant temperature chamber; (V) The fluid in the clamp flows from the oil, gas and water production pipeline into the oil, gas and water metering pipe. The production output and production speed of the oil, gas and water are measured by the oil and water monitoring camera and the gas flow meter, respectively. The online real-time detection of oil and gas components is achieved by the crude oil component detector and the gas component detector. (VI) Adjust the back pressure pump pressure in real time according to the experimental requirements to simulate the CO2 backflow pressure until the end of the experiment.

[0015] The beneficial effects of this invention are: This invention provides an apparatus and method for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields. It can simultaneously evaluate the dynamic effect of CO2 huff and puff, as well as the composition of produced gas and crude oil and the changes of composition with injection time. The operation is simple and convenient. The apparatus can be reused multiple times, the experimental simulation has a high repeatability, and the experiment can be conducted without interruption from the initial preparation to the effect evaluation process, achieving zero carbon emissions during the evaluation process. It solves the problems of traditional online dynamic effect evaluation of CO2 huff and puff requiring multiple sets of equipment and inconsistent detection methods. It has important guiding significance for the research on CO2 huff and puff technology to enhance oil recovery in heavy oil fields and for the efficient development of heavy oil fields. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the device for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields according to the present invention.

[0017] in: 1 CO2 cylinder 2 Pressure reducing valve 3 Pressure regulating valve 4 Valve No. I 5. Injection pump; 6. Valve II 7. Valve No. Ⅲ; 8. CO2 intermediate container 9. Valve No. IV; 10. Valve No. V 11. Intermediate oil container; 12. Valve No. VI 13 Valve VII 14 Intermediate Water Container Valve No. 15 (VIII) and Valve No. 16 (IX) 17 Clamping device 18 Valve X 19 Buffer Container No. 1 20 Valve No. XI 21 Confining pressure pump 22 Valve XII 23 Back pressure valve No. 1 24 Oil-water production pipeline 25 Oil-water metering pipe 26 Oil-water monitoring camera 27 Back pressure pump 28 Valve XIII 29 Valve XIV, 30 Pressure Gauge I 31. Valve XV; 32. Oil, gas, and water metering pipe 33 Oil-water interface 34 Oil-gas interface 35 Oil, gas and water production pipelines 36 Gas output pipelines 37 Crude oil output pipeline 38 Float Valve No. 39 XVI Valve No. 40 XVII 41 Suction pump 42 Metering pump 43 Valve XVIII 44 Crude Oil Component Detector 45 Valve No. XIX 46 Gas Component Detector 47. Produced gas trap 48. Oil-water monitoring camera 49 Data recording and processing system 50 Injection pump data transmission line 51 Back pressure pump data transmission line; 52 Saturated oil-water data transmission line 53 Pressure gauge No. II 54 Pressure data transmission line No. II 55 Confining Pressure Data Transmission Line 56 Pressure Data Transmission Line I 57. Backflow fluid transmission line; 58. Gas flow data transmission line 59 Gas component data transmission line; 60 Crude oil component data transmission line 61 Crude oil suction pump data transmission line 62 Constant temperature chamber 63 Gas flow meter 64 Valve No. XX 65 Buffer container No. Ⅱ; 66 Back pressure valve No. Ⅱ.

[0018] For those skilled in the art, other related figures can be obtained from the above figures without any creative effort. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solution of the present invention, the technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0020] Example 1

[0021] like Figure 1 As shown, an apparatus for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields includes: The injection mechanism provides different injection fluids for the model mechanism; Model structure for simulating target reservoirs with CO2 huff and puff; Oil-water saturation mechanism to achieve oil-water saturation of the model mechanism; Pressure control mechanism, used to control the pressure throughout the CO2 throughput simulation; Temperature control mechanism used to control the temperature throughout the CO2 throughput simulation; The output metering and component analysis unit is used to realize the output metering and online detection of oil and gas components during the CO2 huff and puff process; The data control mechanism is used to collect data such as temperature, pressure, output, and composition throughout the CO2 throughput simulation. The various institutions work together organically, coordinating their efforts in a sequential manner, to evaluate the online dynamic effects of CO2 throughput in heavy oil fields.

[0022] The injection mechanism includes a CO2 injection mechanism, an oil injection mechanism, and a water injection mechanism, which are respectively connected to the model mechanism, as well as a power source. The CO2 injection mechanism includes a CO2 cylinder 1 and a CO2 intermediate container 8, which are respectively connected to the model mechanism. The CO2 intermediate container 8 is connected to a power source. The oil injection mechanism includes an intermediate oil container 11, one end of which is connected to the model mechanism and the other end is connected to a power source. The water injection mechanism includes a water intermediate container 14, one end of which is connected to the model mechanism and the other end is connected to the power source; In this embodiment, a pressure reducing valve 2, a pressure regulating valve 3, and valve 4 (No. I) are sequentially installed on the pipeline between the CO2 cylinder 1 and the model mechanism; the pressure reducing valve 2 is located close to the CO2 cylinder 1; valve 9 (No. IV) is installed on the pipeline between the CO2 intermediate container 8 and the model mechanism, and valve 7 (No. III) is installed on the pipeline between the CO2 intermediate container 8 and the power source; the CO2 cylinder 1, pressure reducing valve 2, pressure regulating valve 3, and valve 4 (No. I) work together to provide CO2 gas to the CO2 intermediate container 8, thus replenishing the CO2 gas in the CO2 intermediate container 8; valve 7 (No. III), the CO2 intermediate container 8, valve 9 (No. IV), the injection pump 5, and valve 6 (No. II) work together to pressurize the CO2 in the CO2 intermediate container 8 to the pressure required for the experiment; In this embodiment, valve VI 12 is installed on the pipeline between the intermediate oil container 11 and the model mechanism, and valve V 10 is installed on the pipeline between the intermediate oil container 11 and the power source; In this embodiment, valve VIII 15 is installed on the pipeline between the intermediate water container 14 and the model mechanism, and valve VII 13 is installed on the pipeline between the intermediate water container 14 and the power source; In this embodiment, the power source is an injection pump 5, and valve 6 of type II is installed at the output end of the injection pump 5; the power source provides power to the injection mechanism and adjusts the injection speed and pressure control according to experimental requirements.

[0023] The model mechanism includes a clamp 17, one end of which is connected to the injection mechanism and the other end is connected to the oil-water saturation mechanism. Valve IX 16 is installed on the pipeline between the clamp 17 and the injection mechanism, and valve XII 22 is installed on the pipeline between the clamp 17 and the oil-water saturation mechanism. The clamp 17 is used for simulating the CO2 huff and puff target reservoir. In this embodiment, a pressure gauge 30 is installed between valve IX 16 and clamp 17, and a pressure gauge 53 is installed between clamp 17 and valve XII 22.

[0024] In this embodiment, the clamp 17 has a maximum pressure resistance of 100 MPa and a temperature resistance of 180°C, and its length is adjustable from 5 cm to 200 cm. The clamp 17 has a diameter of 1 inch and is made of Hastelloy alloy. The clamp 17 is a core displacement clamp and is a commercially available conventional product.

[0025] The oil-water saturation mechanism includes an oil-water metering pipe 25 and an oil-water monitoring camera 26 located beside the oil-water metering pipe 25. The oil-water metering pipe 25 is connected to the model mechanism through an oil-water production pipeline 24. The oil-water monitoring camera 26 can monitor the amount and speed of oil and water production in the oil-water metering pipe 25 in real time, and can realize the real-time online saturation of the clamp 17 in the model system.

[0026] The pressure control mechanism includes a back pressure pump 27, a back pressure control mechanism, and a return back pressure control mechanism. The back pressure control mechanism includes a back pressure valve 23 disposed between the model mechanism and the oil-water saturation mechanism, and a No. II buffer container 65 connected to the back pressure valve 23. The other end of the No. II buffer container 65 is connected to a back pressure pump 27. The back pressure control mechanism and the back pressure pump 27 can realize the back pressure control of the clamp 17 in the model system, thereby realizing that the pressure of the clamp 17 in the model system is consistent with the formation pressure simulated in the experiment. In this embodiment, valve XIII 28 is provided between buffer container II 65 and back pressure pump 27, and valve XX 64 is provided between buffer container II 65 and back pressure valve 23; The backpressure control includes a No. II backpressure valve 66 located between the injection mechanism and the production metering and component analysis mechanism. The No. II backpressure valve 66 is connected to the backpressure pump 27, and a No. XIV valve 29 is installed on the pipeline between the two. A No. XV valve 31 is installed on the pipeline between the No. II backpressure valve 66 and the production metering and component analysis mechanism. Through the effective combination of the backpressure pump 27, the No. XIV valve 29, and the No. II backpressure valve 66, the backpressure control of the clamp 17 in the model system can be realized, thereby making the backpressure of the clamp 17 in the model system consistent with the formation backpressure simulated in the experiment. In this embodiment, the pressure control mechanism further includes a No. I buffer container 19 and a confining pressure pump 21 connected to each other, and a No. XI valve 20 is installed on the pipeline between the two. The No. I buffer container 19 is connected to the clamp 17, and a No. X valve 18 is installed on the pipeline between the two. The back pressure pump of the pressure control system can simultaneously realize the back pressure control of the oil-water saturated system and the back pressure control of the pressure control system in the whole model. Moreover, the back pressure pump can realize the linear reduction of pressure during the back flow of CO2 in the clamp 17 of the model system, and realistically simulate the back flow process of the formation.

[0027] The output metering and component analysis mechanism includes an oil, gas and water metering pipe 32, a gas detection mechanism connected to the oil, gas and water metering pipe 32 through a gas output pipeline 36, and a crude oil detection mechanism connected to the oil, gas and water metering pipe 32 through a crude oil output pipeline 37; an oil and water monitoring camera 48 is installed on the side of the oil, gas and water metering pipe 32. The gas detection mechanism includes a gas component detector 46 and a produced gas collector 47 connected to each other. On the pipeline between the gas component detector 46 and the oil, gas and water metering pipe 32, valve XVII 40, gas flow meter 63 and valve XIX 45 are sequentially installed. The crude oil testing mechanism includes a suction pump 41, a metering pump 42 and a crude oil component detector 44 connected in sequence. A valve 43 of XVIII is provided between the suction pump 41 and the metering pump 42, and a valve 39 of XVI is provided between the suction pump 41 and the oil, gas and water metering pipe 32. A float 38 is installed at one end of the crude oil output pipeline 37 that extends into the oil-gas-water metering pipe 32. The float 38 is suspended between the oil-water interface 33 and the oil-gas interface 34 of the oil-gas-water metering pipe 32. The suspension depth can be adjusted by the density of the float 38, thereby ensuring that the fluid pumped by the suction pump 41 during operation is crude oil. The pumping speed of the suction pump 41 can be adjusted in real time according to the liquid level height of the oil-water interface 33 and the oil-gas interface 34. The oil, gas and water metering pipe 32 is connected to the injection mechanism through the interconnected oil, gas and water production pipeline 35 and the return fluid transmission pipeline 57. The free end of the oil, gas and water production pipeline 35 located inside the oil, gas and water metering pipe 32 is horizontally lower than the gas output pipeline 36 and higher than the float 38. The oil-water monitoring camera 48 can realize real-time monitoring of the oil-water interface 33 and the oil-gas interface 34 in the oil-gas-water metering pipe 32, thereby realizing the oil-water production rate and flow rate during the CO2 backflow process; the gas flow meter 63 can monitor the gas production rate and flow rate during the CO2 backflow process in real time; through the effective combination of the gas output pipeline 36, valve XVII 40, gas flow meter 63, valve XIX 45, and gas component detector 46, the flow rate, velocity, and composition of the produced gas can be detected in real time. The system can measure and detect the content ratio of various components in the produced mixed gas online. The produced gas after detection can be collected through the produced gas trap 47, thereby achieving zero carbon emissions for the entire model. Through the effective combination of crude oil output pipeline 37, float 38, valve XVI 39, suction pump 41, metering pump 42, valve XVIII 43, and crude oil component detector 44, the system can achieve real-time detection of the components in the produced crude oil and detect the content ratio of various components in the produced oil sample online. The data control mechanism includes a data recording and processing system 49, which is electrically connected to the injection pump 5 via the injection pump data transmission line 50, to the back pressure pump 27 via the back pressure pump data transmission line 51, to the oil-water monitoring camera 26 via the saturated oil-water data transmission line 52, to pressure gauge 53 via ...

[0028] The model mechanism, oil-water saturation mechanism, output metering and component analysis mechanism, and pressure control mechanism are all located inside the constant temperature chamber 62.

[0029] The simulation principle of this invention: The oil and water in the intermediate oil container 11 and intermediate water container 14 of the injection system are injected into the clamp 17 of the model system through the injection pump 5 and then flow into the oil and water metering pipe 25 of the oil and water saturation system, thereby achieving oil and water saturation of the model. CO2 in the intermediate CO2 container 8 of the injection system is injected into the clamp 17 of the model system through the injection pump 5, thereby simulating the injection process in CO2 throughput. The fluid in the clamp 17 of the model system flows into the oil, gas and water metering pipe 32 of the output metering and component analysis system, thereby realizing the backflow of simulated CO2 throughput.

[0030] The components of the device for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields are organically connected and work synergistically in sequence to achieve the evaluation of the online dynamic effect of CO2 huff and puff in heavy oil fields.

[0031] This invention enables online detection of dynamic produced gas components during CO2 huff and puff in heavy oil fields, online detection of produced crude oil components, automatic online metering of produced fluids, automatic control of back pressure during heavy oil huff and puff backflow, real-time monitoring and control of pressure / temperature throughout the process, online evaluation of dynamic CO2 huff and puff effects, zero carbon emissions throughout the process, real-time sampling of produced crude oil, and online operation and control of the entire process.

[0032] Example 2

[0033] A method for using a device for online dynamic evaluation of CO2 huff and puff effects in heavy oil fields includes the following steps: Step 1: Close valves 10 (V), 12 (VI), 13 (VII), 15 (VIII), 16 (IX), 18 (X), 20 (XI), 22 (XII), 28 (XIII), 29 (XIV), 31 (XV), 39 (XVI), 40 (XVII), pump 41 (suction pump), 43 (XVIII), 45 (XIX), and 64 (XX). Open valves 4 (I), 9 (IV), 6 (II), and 7 (III). Adjust pressure reducing valve 2 and pressure regulating valve 3 to replenish CO2 in CO2 cylinder 1 to the intermediate CO2 container 8, and bring the pressure to the required experimental pressure. Then close valves 4 (I) and 7 (III) to complete the CO2 replenishment. Step 2: Set the temperature of the 62 constant temperature chamber to the experimental temperature, open valve 18 of X and valve 20 of XI, and start the confining pressure pump 21 until the pressure reaches the experimental confining pressure; open valve 28 of XIII and valve 64 of XX, and start the back pressure pump 27 until the pressure reaches the experimental back pressure; Step 3: Open valves VII (13), VIII (15), IX (16), and XII (22), set the displacement speed of injection pump 5 to the experimental speed, and start injection pump 5. Fluid will flow from the oil-water production pipeline 24 into the oil-water metering pipe 25. Monitor the output and flow rate of the produced fluid using the oil-water monitoring camera 26 until it matches the injection flow rate of injection pump 5, then close injection pump 5. Close valves VII (13) and VIII (15), and open valves V (10) and VI (12). Set the displacement speed of injection pump 5 to the experimental speed and start injection pump 5. The fluid flows into oil and water metering pipe 25 through oil and water production pipeline 24. Monitor the output and flow rate of the produced fluid through oil and water monitoring camera 26 until it is consistent with the injection flow rate of injection pump 5. Then shut down injection pump 5 and back pressure pump 27. Close valves 10 (V), 12 (VI), 16 (IX), 22 (XII), and 28 (XIII). Age clamp 17 in constant temperature chamber 62 for 24 hours. Step 4: Open valves 7 (III), 9 (IV), and 16 (IX), set the displacement speed of injection pump 5 to the experimental speed and start injection pump 5 to inject CO2 into clamp 17, then close injection pump 5, valves 7 (III), 9 (IV), and 16 (IX). The aging time of clamp 17 in constant temperature chamber 62 shall be determined by the experiment. Step 5: Open valves XIV 29 and XV 31, start back pressure pump 27 until the pressure reaches the experimental back pressure, open valve IX 16 so that the fluid in clamp 17 flows from oil, gas and water production pipeline 35 into oil, gas and water metering pipe 32, open valves XVII 40, XIX 45, XVI 39, and XVIII 43, use oil and water monitoring camera 48 and gas flow meter 63 to measure the output and production speed of oil, gas and water respectively, and use crude oil component detector 44 and gas component detector 46 to realize online real-time detection of oil and gas components; Step 6: Adjust the back pressure pump 27 in real time according to the experimental requirements to simulate the CO2 backflow pressure until the end of the experiment.

[0034] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0035] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0036] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0037] The applicant declares that the above description is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention fall within the protection and disclosure scope of the present invention.

Claims

1. A device for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields, characterized in that: include: The injection mechanism provides different injection fluids for the model mechanism; Model structure for simulating target reservoirs with CO2 huff and puff; Oil-water saturation mechanism to achieve oil-water saturation of the model mechanism; Pressure control mechanism, used to control the pressure throughout the CO2 throughput simulation; Temperature control mechanism used to control the temperature throughout the CO2 throughput simulation; The output metering and component analysis unit is used to realize the output metering and online detection of oil and gas components during the CO2 huff and puff process; The data control mechanism is used to collect temperature, pressure, output, and composition data throughout the CO2 throughput simulation. The oil-water saturation mechanism includes an oil-water metering pipe (25) and an oil-water monitoring camera (26) located next to the oil-water metering pipe (25). The oil-water metering pipe (25) is connected to the model mechanism through an oil-water production pipeline (24). The pressure control mechanism includes a back pressure pump (27), a back pressure control mechanism, and a return back pressure control mechanism; the back pressure control mechanism includes a back pressure valve (23) disposed between the model mechanism and the oil-water saturation mechanism, and a No. II buffer container (65) connected to the back pressure valve (23), the other end of the No. II buffer container (65) being connected to the back pressure pump (27); a No. XIII valve (28) is disposed between the No. II buffer container (65) and the back pressure pump (27), and a No. XX valve (64) is disposed between the No. II buffer container (65) and the back pressure valve (23); the return back pressure control mechanism includes a back pressure pump (27), a back pressure control mechanism, and a return back pressure control mechanism; the back pressure control mechanism includes a back pressure valve (23) disposed between the injection mechanism and the oil-water saturation mechanism, and a No. XX buffer container (64) connected to the back pressure valve (23); the return back pressure control mechanism includes a back pressure pump (27), a back pressure control mechanism, and a return back pressure control mechanism; the back pressure control mechanism includes a back pressure valve (23) disposed between the injection mechanism and the oil-water saturation ... The pressure control mechanism includes a No. II back pressure valve (66) between the output metering and component analysis unit and a back pressure pump (27). The No. II back pressure valve (66) is connected to the back pressure pump (27), and a No. XIV valve (29) is installed on the pipeline between the two. A No. XV valve (31) is installed on the pipeline between the No. II back pressure valve (66) and the output metering and component analysis unit. The pressure control mechanism also includes a No. I buffer container (19) and a confining pressure pump (21) connected to each other. A No. XI valve (20) is installed on the pipeline between the two. The No. I buffer container (19) is connected to the clamp (17), and a No. X valve (18) is installed on the pipeline between the two. The output metering and component analysis mechanism includes an oil, gas and water metering pipe (32), a gas detection mechanism connected to the oil, gas and water metering pipe (32) through a gas output pipeline (36), and a crude oil detection mechanism connected to the oil, gas and water metering pipe (32) through a crude oil output pipeline (37). A No. II oil-water monitoring camera (48) is installed beside the oil-gas-water metering pipe (32); the gas detection mechanism includes a gas component detector (46) and a produced gas trap (47) connected to each other, and valves No. XVII (40), a gas flow meter (63), and valves No. XIX (45) are installed in sequence on the pipeline between the gas component detector (46) and the oil-gas-water metering pipe (32); the crude oil detection mechanism includes a suction pump (41), a metering pump (42), and a crude oil component detector (44) connected in sequence, and the suction pump (41) and A valve (43) of type XVIII is installed between the metering pump (42), and a valve (39) of type XVI is installed between the suction pump (41) and the oil-gas-water metering pipe (32); a float (38) is installed at one end of the crude oil output pipeline (37) that extends into the oil-gas-water metering pipe (32), and the float (38) is suspended between the oil-water interface (33) and the oil-gas interface (34) of the oil-gas-water metering pipe (32); the oil-gas-water metering pipe (32) is connected to the injection mechanism through the interconnected oil-gas-water production pipeline (35) and the return fluid transmission pipeline (57).

2. The device for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields according to claim 1, characterized in that: The injection mechanism includes a CO2 injection mechanism, an oil injection mechanism, and a water injection mechanism that are respectively connected to the model mechanism, as well as a power source. The CO2 injection mechanism includes a CO2 cylinder (1) and a CO2 intermediate container (8) that are respectively connected to the model mechanism. The CO2 intermediate container (8) is connected to the power source. The oil injection mechanism includes an oil intermediate container (11), one end of which is connected to the model mechanism and the other end of which is connected to the power source. The water injection mechanism includes a water intermediate container (14), one end of which is connected to the model mechanism and the other end of which is connected to the power source.

3. The device for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields according to claim 2, characterized in that: A pressure reducing valve (2), a pressure regulating valve (3), and valve I (4) are sequentially installed on the pipeline between the CO2 cylinder (1) and the model mechanism; the pressure reducing valve (2) is located close to the CO2 cylinder (1); valve IV (9) is installed on the pipeline between the CO2 intermediate container (8) and the model mechanism, and valve III (7) is installed on the pipeline between the CO2 intermediate container (8) and the power source.

4. The device for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields according to claim 2, characterized in that: A valve VI (12) is installed on the pipeline between the oil intermediate container (11) and the model mechanism, and a valve V (10) is installed on the pipeline between the oil intermediate container (11) and the power source; a valve VIII (15) is installed on the pipeline between the water intermediate container (14) and the model mechanism, and a valve VII (13) is installed on the pipeline between the water intermediate container (14) and the power source; the power source is an injection pump (5), and a valve II (6) is installed at the output end of the injection pump (5).

5. The apparatus for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields according to claim 1, characterized in that: The model mechanism includes a clamp (17), one end of which is connected to the injection mechanism and the other end is connected to the oil-water saturation mechanism. A valve IX (16) is installed on the pipeline between the clamp (17) and the injection mechanism, and a valve XII (22) is installed on the pipeline between the clamp (17) and the oil-water saturation mechanism. A pressure gauge I (30) is installed between the valve IX (16) and the clamp (17), and a pressure gauge II (53) is installed between the clamp (17) and the valve XII (22).

6. The apparatus for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields according to claim 1, characterized in that: The model mechanism, oil-water saturation mechanism, output metering and component analysis mechanism, and pressure control mechanism are located inside the constant temperature chamber (62).

7. A method for evaluating the online dynamic effect of CO2 huff and puff in heavy oil fields based on the device described in any one of claims 1 to 6, characterized in that: Includes the following steps: (I) Add CO2 to the intermediate CO2 container to the pressure required for the experiment; (II) Set the temperature of the constant temperature chamber to the experimental temperature, start the confining pressure pump to the experimental confining pressure, and start the return pressure pump to the experimental return pressure; (III) The fluid in the oil-water production pipeline flows into the oil-water metering pipe, and the clamp is aged in a constant temperature chamber; (IV) Inject CO2 into the clamp and age the clamp in a constant temperature chamber; (V) The fluid in the clamp flows from the oil, gas and water production pipeline into the oil, gas and water metering pipe. The No. II oil and water monitoring camera and the gas flow meter are used to measure the output and production rate of the oil, gas and water respectively. The online real-time detection of oil and gas components is achieved by using the crude oil component detector and the gas component detector. (VI) Adjust the back pressure pump pressure in real time according to the experimental requirements to simulate the CO2 backflow pressure until the end of the experiment.

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