A system and method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics

Abstract

The present application discloses a system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, which includes two etched transparent dielectric sheets with pore structures for reflecting steam channeling dominant channels in the middle disposed on a heating device. The injection parts of the etched transparent dielectric sheets are connected with a steam generating device, an oil storage device and a particle suspension storage device, and the other ends of the two are commonly connected to a first displacement device. The other end of the steam generating device is connected to a second displacement device. The oil outlet parts of the etched transparent dielectric sheets are connected with a liquid production collection device and an image acquisition device is arranged above. The image acquisition device and the heating device are electrically connected to a data acquisition and analysis device. This system enables experimenters to observe the plugging and profile control process of steam and plugging agent particles and the oil production effect after steam channeling in heavy oil reservoirs at the pore scale, further explore the development potential after steam channeling in heavy oil reservoirs, and has higher simulation accuracy. The present application also discloses a method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics.

Description

Technical Field

[0001] The present invention belongs to the technical field of heavy oil reservoir development, and particularly relates to a system and method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics. Background Technique

[0002] The heavy oil resources in the world are extremely rich, and heavy oil has also become an important part of China's crude oil production. In terms of the utilization of heavy oil resources, the heavy components in heavy oil are often used to refine high-end lubricating oil, high-grade asphalt, refrigeration oil and other substances. In the case of increasingly prominent international energy contradictions, vigorously developing heavy oil resources meets the needs of China's economy, energy and strategic security.

[0003] Due to the high viscosity of heavy oil, steam injection is usually used to develop heavy oil reservoirs. Among them, steam huff and puff is the most widely used heavy oil thermal recovery development method. After multiple rounds of steam huff and puff, steam flooding becomes the main subsequent development method. Due to the heterogeneity within or between layers of heavy oil reservoirs, unreasonable steam injection parameters or steam override, in the later stage of heavy oil reservoir thermal recovery development, inter-well channeling channels develop, resulting in a decrease in the sweep efficiency of steam or hot water, and a large amount of residual oil remains in the formation. To further improve the recovery rate, effectively plugging the dominant steam channeling channels has become an important means to improve the development effect of heavy oil reservoirs in the later stage of steam development.

[0004] In the prior art, when simulating and studying steam channeling plugging and profile control in heavy oil reservoirs, an experimental system and method for evaluating the exploitation of heavy oil assisted by air foam steam flooding are adopted, and an experimental device of parallel sand-filled pipes is used for experiments, as Figure 1 shown Figure 1FIG. 0 is a schematic structural diagram of an experimental system for evaluating heavy oil recovery by air foam-assisted steam flooding in the prior art, which includes an air bottle 21, a dryer 22, a gas flow measurement and control device 23, a one-way valve 24, a first precision pressure gauge 25, a first ISCO injection pump 26, an intermediate container 27, a foam generator 28, a first back pressure valve 29, a second precision pressure gauge 210, a second ISCO injection pump 211, a steam generator 212, a second back pressure valve 213, a third precision pressure gauge 214, an injection pipeline 215 with a heat tracing device, a first beaker 217, a second beaker 219, a first production heat tracing pipeline 41, a third back pressure valve 42, a fourth precision pressure gauge 43, a first wide-mouth bottle with a stopper 44, a first gas sample collection bag 45, a second production heat tracing pipeline 46, a fourth back pressure valve 47, a fifth precision pressure gauge 48, a second wide-mouth bottle with a stopper 49, a second gas sample collection bag 410, and a data acquisition device 3 including a data acquisition and transmission device 31, a computer 32, a power supply 33, a core device 1A, a first core 16, a second core 16A, a connection device 162, a first sand-filled tube 161, and a second sand-filled tube 167. This experimental system and method can better evaluate the profile control effect of the injected medium after steam channeling in a heavy oil reservoir, but this experimental system and method cannot allow people to observe the process and effect of particle plugging profile control in a heavy oil reservoir at the pore scale after steam channeling. At the same time, in this traditional physical simulation of a sand-filled tube, there are disadvantages such as a long experimental period, a large workload for personnel, and a large consumption of samples. SUMMARY OF THE INVENTION

[0005] To solve the above problems, the present invention provides a system and method for simulating steam channeling plugging and profile control in a heavy oil reservoir based on microfluidics, which can enable an experimenter to observe the plugging and profile control process of steam and plugging agent particles and the oil production effect at the pore scale after steam channeling in a heavy oil reservoir, enabling people to more deeply understand and evaluate the plugging and profile control process and effect of plugging agent particles in a heavy oil reservoir in the later stage of thermal recovery development, further exploring the development potential after steam channeling in a heavy oil reservoir, and having higher simulation accuracy, simpler operation, a shorter experimental period, and less sample consumption.

[0006] A system for simulating steam channeling plugging and profile control in a heavy oil reservoir based on microfluidics provided by the present invention includes two etched transparent dielectric sheets with a pore structure for reflecting steam channeling dominant channels in the middle, which are arranged on a heating device. The injection parts of the etched transparent dielectric sheets are connected to a steam generation device, an oil storage device, and a particle suspension storage device. The other ends of the oil storage device and the particle suspension storage device are commonly connected to a first displacement device, and the other end of the steam generation device is connected to a second displacement device. The oil outlet part of the etched transparent dielectric sheet is connected to a liquid production collection device, and an image acquisition device is arranged above it. The image acquisition device and the heating device are commonly electrically connected to a data acquisition and analysis device.

[0007] Preferably, in the above-mentioned system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, a pressure sensor is further provided at the front end of the injection part of the etched transparent medium sheet, and the pressure sensor is electrically connected to the data acquisition and analysis device.

[0008] Preferably, in the above-mentioned system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, a flow sensor is further provided at the front end of the injection part of the etched transparent medium sheet, and the flow sensor is electrically connected to the data acquisition and analysis device.

[0009] Preferably, in the above-mentioned system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, the image acquisition device is an electron microscope.

[0010] Preferably, in the above-mentioned system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, a light source device facing the etched transparent medium sheet is further included.

[0011] Preferably, in the above-mentioned system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, the transparent etched medium sheet is an etched glass sheet.

[0012] Preferably, in the above-mentioned system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, the first displacement device includes a micro displacement pump that is connected to both the oil storage device and the particle suspension storage device, and a micro compressor connected to the other end of the micro displacement pump.

[0013] Preferably, in the above-mentioned system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, the second displacement device is a high-precision displacement pump.

[0014] Preferably, in the above-mentioned system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, the heating device is a heating plate that can be set to the formation temperature.

[0015] A method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics provided by the present invention uses the system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics as described in any one of the above, and includes:

[0016] Set the temperature of the heating device to the formation temperature, and place the etched transparent medium sheet on the heating device;

[0017] Inject heavy oil into the oil storage device, use the first displacement device to displace the oil storage device to saturate the oil sample in the injection part of the etched transparent medium sheet, and turn on the image acquisition device;

[0018] Use the second displacement device to inject the steam generated by the steam generating device into the etched transparent medium sheet until the water cut of the produced liquid reaches a preset threshold and then stop;

[0019] Use the first displacement device to displace the particle suspension storage device to inject a particle suspension with a volume that is a preset multiple of the pore volume into the etched transparent medium sheet;

[0020] Use the second displacement device again to inject the steam generated by the steam generation device into the etched transparent medium sheet until the water cut of the produced fluid reaches a preset threshold and then stop;

[0021] Use the data acquisition and analysis device to record the microscopic images, injection speed, and injection time during the displacement process collected by the image acquisition device, and record the water production volume in the produced fluid collection device;

[0022] Calculate different injection pore volume multiples using the injection speed, the injection time, and the total pore volume of the etched transparent medium sheet to obtain a relationship curve between the injection speed and the injection pore volume multiple;

[0023] Calculate the recovery factor through the total saturated oil volume in the etched transparent medium sheet and the oil saturation corresponding to different injection pore volume multiples to obtain a relationship curve between the recovery factor and the injection pore volume multiple, and analyze the oil production effect of plugging and diverting the steam channel in the heavy oil reservoir;

[0024] Calculate the water cut through the total saturated oil volume, the recovery factor, and the water production volume in the etched transparent medium sheet to obtain a relationship curve between the water cut and the injection pore volume multiple.

[0025] As can be seen from the above description, the system for simulating steam channel plugging and diverting in heavy oil reservoirs based on microfluidics provided by the present invention includes two etched transparent medium sheets with pore structures for reflecting steam channeling dominant channels in the middle disposed on a heating device. The injection part of the etched transparent medium sheet is connected to a steam generation device, an oil storage device, and a particle suspension storage device. The other ends of the oil storage device and the particle suspension storage device are commonly connected to a first displacement device. The other end of the steam generation device is connected to a second displacement device. The oil outlet part of the etched transparent medium sheet is connected to a produced fluid collection device and an image acquisition device is disposed above it. The image acquisition device and the heating device are commonly electrically connected to a data acquisition and analysis device. Therefore, it enables experimenters to observe the plugging and diverting process of steam and plugging agent particles and the oil production effect after steam channeling in heavy oil reservoirs at the pore scale, enabling people to more deeply understand and evaluate the plugging and diverting process and effect of plugging agent particles in heavy oil reservoirs during the late stage of thermal recovery development, further exploring the development potential after steam channeling in heavy oil reservoirs, and having higher simulation accuracy, simpler operation, shorter experimental period, and less sample consumption. The present invention also provides a method for simulating steam channel plugging and diverting in heavy oil reservoirs based on microfluidics, which has the same advantages as the above system. Description of the Drawings

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained according to the provided drawings.

[0027] Figure 1 It is a schematic structural diagram of an experimental system for evaluating the heavy oil recovery by air foam assisted steam flooding in the prior art;

[0028] Figure 2 It is a schematic diagram of an embodiment of a system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics provided by the present invention;

[0029] Figure 3 It is a schematic diagram of a specific embodiment of a system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics;

[0030] Figure 4 It is a schematic diagram of an embodiment of a method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics provided by the present invention;

[0031] Figure 5 It is the effect diagram of particle plugging and profile control for steam channeling in heavy oil reservoirs;

[0032] Figure 6 It is a schematic diagram of the relationship curves of injection rate, water cut and recovery factor at different injection pore volume multiples. Detailed implementation manners

[0033] The core of the present invention is to provide a system and method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, which can enable experimenters to observe the plugging and profile control process of steam and plugging agent particles after steam channeling in heavy oil reservoirs at the pore scale, and to more deeply understand and evaluate the plugging and profile control process and effect of plugging agent particles in heavy oil reservoirs in the later stage of thermal recovery development, further explore the development potential after steam channeling in heavy oil reservoirs, and have higher simulation accuracy, simpler operation, shorter experimental period and less sample consumption.

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0035] An embodiment of a system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics provided by the present invention is as Figure 2 shown. Figure 2Schematic diagram of an embodiment of a system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics provided by the present invention. The system may include two etched transparent dielectric sheets 2 disposed on a heating device 1 and having a pore structure in the middle for reflecting the dominant steam channeling channels. The injection part of the etched transparent dielectric sheet 2 is connected to a steam generating device 3, an oil storage device 4, and a particle suspension storage device 5. The oil storage device 4 and the particle suspension storage device 5 can be fixed by a fixing plate. The other ends of the oil storage device 4 and the particle suspension storage device 5 are commonly connected to a first displacement device 6, and the other end of the steam generating device 3 is connected to a second displacement device 7. The oil outlet part of the etched transparent dielectric sheet 2 is connected to a liquid production collection device 8 and an image acquisition device 9 is disposed above it. The lens of the image acquisition device 9 can be directly facing the etched transparent dielectric sheet 2. The liquid production collection device 8 can be a test tube fixed on a test tube holder. The image acquisition device 9 and the heating device 1 are commonly electrically connected to a data acquisition and analysis device 10.

[0036] It should be noted that the above embodiment is a microscopic visualization system. The working process using this system can be as follows: Place the etched transparent dielectric sheet 2 on the heating device 1 and set it to the formation temperature; prepare heavy oil and particle suspension; saturate the etched transparent dielectric sheet 2 with heavy oil; inject steam into the etched transparent dielectric sheet 2 to form steam channeling channels, inject particle suspension to plug the steam channeling channels, and then inject steam to divert to the uninvaded oil area until the water cut reaches 98%. Record the images, injection speed, and injection time of the displacement process through the data acquisition and analysis device 10 connected to the image acquisition device 9, record the oil production and water production of the test tube; plot the relationship curves of injection speed, water cut, recovery rate, and injection pore volume multiple; obtain the oil production effect of the steam channeling plugging and profile control technology in heavy oil reservoirs.

[0037] From the above description, it can be seen that in the embodiment of the system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics provided by the present invention, since it includes two etched transparent dielectric sheets disposed on a heating device and having a pore structure in the middle for reflecting the dominant steam channeling channels, the injection part of the etched transparent dielectric sheet is connected to a steam generating device, an oil storage device, and a particle suspension storage device, the other ends of the oil storage device and the particle suspension storage device are commonly connected to a first displacement device, the other end of the steam generating device is connected to a second displacement device, the oil outlet part of the etched transparent dielectric sheet is connected to a liquid production collection device and an image acquisition device is disposed above it, and the image acquisition device and the heating device are commonly electrically connected to a data acquisition and analysis device, it is possible for experimenters to observe the plugging and profile control process of steam and plugging agent particles after steam channeling in heavy oil reservoirs at the pore scale, enabling people to more deeply understand and evaluate the plugging and profile control process and effect of plugging agent particles in heavy oil reservoirs during the later stage of thermal recovery development, further exploring the development potential of heavy oil reservoirs after steam channeling, and having higher simulation accuracy, simpler operation, shorter experimental period, and less sample consumption.

[0038] In a specific embodiment of the above system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, refer to Figure 3 , Figure 3 As a schematic diagram of a specific embodiment of the system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, a pressure sensor 11 can also be provided at the front end of the injection part of the etched transparent dielectric sheet 2, and the pressure sensor 11 is electrically connected to the data acquisition and analysis device 10. In this way, by setting the pressure sensor 11 closer to the etched transparent dielectric sheet 2, the pressure magnitude during the injection process can be measured more accurately in real time, and the collected pressure data can be transmitted to the data acquisition and analysis device 10 in real time. Moreover, a flow sensor 12 can also be provided at the front end of the injection part of the etched transparent dielectric sheet 2, and the flow sensor 12 is electrically connected to the data acquisition and analysis device 10. In this way, by also setting the flow sensor 12 closer to the etched transparent dielectric sheet 2, the flow rate magnitude during the injection process can be measured more accurately in real time, and the collected flow rate data can be transmitted to the data acquisition and analysis device 10 in real time.

[0039] Continue to refer to Figure 3 , the above image acquisition device 9 can preferably be an electron microscope. It should be noted that this electron microscope can directly observe the structure of the sample surface. The size of the sample can be as large as 120mm×80mm×50mm. The sample preparation process is simple and does not require slicing. The sample can be translated and rotated in three dimensions in the sample chamber. Therefore, the sample can be observed from various angles, with a large depth of field and a three-dimensional rich image. The depth of field of the scanning electron microscope is hundreds of times larger than that of the optical microscope and dozens of times larger than that of the transmission electron microscope. The magnification range of the image is wide and the resolution is relatively high, which can be magnified from more than ten times to hundreds of thousands of times. It basically includes the magnification range from magnifying glass, optical microscope to transmission electron microscope. The resolution is between that of the optical microscope and the transmission electron microscope, reaching 3nm. The damage and contamination of the electron beam to the sample are relatively small. While observing the morphology, micro-area composition analysis can also be performed using other signals emitted from the sample. Further, a light source device 13 facing the etched transparent dielectric sheet 2 can also be included. By using this light source device 13, the etched transparent dielectric sheet 2 can be assisted in irradiation to make it brighter, so that the image acquisition device 9 can collect clearer images, which is more convenient for obtaining details in the images and making the analysis more accurate. The specific type of the light source device used can be set according to actual needs, such as LED light source, etc., which is not limited here.

[0040] In another specific embodiment of the above system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, the above transparent etched dielectric sheet 2 can preferably be an etched glass sheet. It should be noted that this glass material can withstand higher temperatures. Therefore, in this heavy oil experiment, the experimental temperature range is larger, and the real situation in the formation can be simulated better. Moreover, continue to refer toFigure 3 Specifically, the first displacement device 6 may include a micro displacement pump 601 that is connected to both the oil storage device 4 and the particle suspension storage device 5, and a micro compressor 602 that is connected to the other end of the micro displacement pump 601. Using such a micro compressor and a micro displacement pump, viscous oil and particle suspension can be displaced into the transparent etching medium sheet 2 to meet the requirements of the simulation experiment. In addition, the second displacement device 7 may preferably be a high-precision displacement pump, which is more suitable for steam displacement of viscous oil. In this way, the displacement volume can be controlled more precisely, making it more suitable for displacing steam into the transparent etching medium sheet 2 to meet the requirements of a more precise simulation experiment. It should also be noted that the heating device 1 may be a heating plate that can be set to the formation temperature, which can better simulate the situation in the formation, making the scenario more realistic and the analysis results more in line with the actual situation. Of course, in addition to being plate-shaped, it can also be other types of heating devices, and there is no limitation here.

[0041] It should also be noted that, continuing to refer to Figure 3 Specifically, a multi-way valve 14 can be used for connection. Specifically, the multi-way valve 14 can be used to connect the oil storage device 4, the particle suspension storage device 5, the steam generation device 3, and the inlet end of the transparent etching medium sheet 2 at the same time. Moreover, the data acquisition and analysis device 10 can be a computer, which can simultaneously implement functions such as data acquisition, storage, and analysis.

[0042] An embodiment of a method for simulating steam channeling plugging adjustment in a heavy oil reservoir based on microfluidics provided by the present invention is as Figure 4 shown Figure 4 As shown in the schematic diagram of an embodiment of a method for simulating steam channeling plugging adjustment in a heavy oil reservoir based on microfluidics provided by the present invention, using the system for simulating steam channeling plugging adjustment in a heavy oil reservoir based on microfluidics as described in any of the above, the following steps may be included:

[0043] S1: Set the temperature of the heating device to the formation temperature, and place the etched transparent medium sheet on the heating device;

[0044] S2: Inject viscous oil into the oil storage device, and use the first displacement device to displace the oil storage device to saturate the injection part of the etched transparent medium sheet with an oil sample, and turn on the image acquisition device;

[0045] S3: Use the second displacement device to inject the steam generated by the steam generation device into the etched transparent medium sheet until the water cut of the produced fluid reaches a preset threshold and then stop;

[0046] S4: Use the first displacement device to displace the particle suspension storage device to inject a particle suspension with a volume that is a preset multiple of the pore volume into the etched transparent medium sheet;

[0047] S5: Use the second displacement device to inject the steam generated by the steam generation device into the etched transparent dielectric sheet again until the water cut of the produced fluid reaches the preset threshold and then stop;

[0048] S6: Use the data acquisition and analysis device to record the microscopic images, injection speed, and injection time during the displacement process collected by the image acquisition device, and record the water production volume in the produced fluid collection device;

[0049] S7: Calculate different injection pore volume multiples using the injection speed, injection time, and total pore volume of the etched transparent dielectric sheet, and obtain the relationship curve between the injection speed and the injection pore volume multiple;

[0050] S8: Calculate the recovery factor by the total saturated oil volume and the oil saturation corresponding to different injection pore volume multiples in the etched transparent dielectric sheet, obtain the relationship curve between the recovery factor and the injection pore volume multiple, and analyze the oil production effect of plugging and adjusting the steam channeling in the heavy oil reservoir;

[0051] S9: Calculate the water cut by the total saturated oil volume, recovery factor, and water production volume in the etched transparent dielectric sheet, and obtain the relationship curve between the water cut and the injection pore volume multiple.

[0052] The above method will be described in detail with a specific example as follows:

[0053] (1) Statistically analyze the characteristics of the steam channeling dominant channels in the later stage of thermal recovery of the heavy oil reservoir, characterize the characteristics of the steam channeling dominant channels in the heavy oil reservoir, design the pore structure and data, draw the pore structure of the steam channeling characteristics using CAD software, and fabricate a microscopic displacement model reflecting the steam channeling in the heavy oil reservoir through photolithography technology, that is, etch a glass thin slice;

[0054] (2) Compound the heavy oil according to the heavy oil component content and the formation heavy oil viscosity. When the error between the measured viscosity of the compounded heavy oil and the formation heavy oil viscosity does not exceed 5%, the sample preparation is completed, and the compounded heavy oil is injected into the oil storage tank;

[0055] (3) Place the etched glass thin slice on a temperature-controlled heating plate, and set the temperature of the temperature-controlled heating plate (0 - 200°C) to the formation temperature (80°C);

[0056] (4) Start the micro-displacement pump, open the multi-way valve connecting the oil storage device, and displace the oil storage device at a constant speed to saturate the etched glass thin slice with the oil sample. The displacement pressure can be 0.5 MPa. Observe the oil saturation in the pores of the etched glass thin slice through an electron microscope. After the pores in the etched glass thin slice are completely saturated with oil, stop the pump injection, close the multi-way valve, and record the saturated oil volume at the same time;

[0057] (5) Open the multi-way valve of the steam generator, set the temperature of the steam generator at about 200 °C to generate steam, and inject the steam into the etched glass wafer through the steam generator at a pressure of 30 mbar. During the displacement process, record the distribution of heavy oil in the microscopic glass wafer, the steam injection rate, and the injection time through a computer. At the same time, record the oil production and water production in the test tube at different injection times. Stop injecting steam when the water cut of the produced fluid reaches 98%, and then close the multi-way valve;

[0058] (6) Open the multi-way valve connecting the particle suspension storage device, and displace the particle suspension storage device at a pressure of 30 mbar. During the displacement process, record the particle plugging characteristics, the heavy oil distribution state, the steam injection rate, and the injection time in the microscopic glass wafer through a computer. At the same time, record the oil production and water production in the test tube at different injection times. After injecting 0.5 times the pore volume of the particle suspension into the etched glass wafer, stop the pump injection, and then close the micro-flow displacement pump and the multi-way valve;

[0059] (7) Open the multi-way valve of the steam generator, and then inject steam into the etched glass wafer at a constant pressure of 30 mbar. During the displacement process, record the distribution of heavy oil in the microscopic glass wafer, the steam injection rate, and the injection time through a computer. At the same time, record the oil production and water production in the test tube at different injection times. Stop the experiment when the water cut of the produced fluid reaches 98%, and then clean and dry the experimental containers and pipelines with deionized water and nitrogen;

[0060] (8) Record the microscopic images, injection rate, and injection time of the displacement process through the computer connecting the electron microscope and the micro-flow displacement pump, and record the water production in the test tube;

[0061] (9) Through the microscopic images obtained during the experiment, obtain the plugging state of the particles in the steam channeling channel and the remaining oil distribution, as Figure 5 shown. Figure 5 It is the effect diagram of particle plugging and profile control in the steam channeling channel of the heavy oil reservoir. It can be seen that after using the particles in the particle suspension to plug the dominant steam channeling channel (the circled part), the subsequent steam turns to the un-swept area, thereby improving the heavy oil production degree. At the same time, use Photoshop and MATLAB software to analyze the oil saturation of the microscopic pictures during the experiment, and obtain the remaining oil saturation at different injected pore volume multiples in the etched glass wafer;

[0062] (10) Calculate different injected pore volume multiples through the injection rate, injection time, and total pore volume of the etched glass wafer, and draw the relationship curve between the injection rate and the injected pore volume multiple, as Figure 6 shown. Figure 6 It is the schematic diagram of the relationship curve of the injection rate, water cut, and recovery rate at different injected pore volume multiples;

[0063] (11) Calculate the recovery factor by etching the total saturated oil volume in the glass sheet and the oil saturation corresponding to different injection pore volume multiples, and plot the relationship curve between the recovery factor and the injection pore volume multiple. Similarly, as Figure 6 shown, obtain the oil production effect of the steam channel plugging and profile control technology for heavy oil reservoirs;

[0064] (12) Calculate the water cut by etching the total saturated oil volume, recovery factor and water production of the test tube in the glass sheet, and plot the relationship curve between the water cut and the injection pore volume multiple. Similarly, as Figure 6 shown.

[0065] In summary, the above system and method solve the problems existing in the process of particle plugging and profile control after steam channeling in the experimental simulation of heavy oil reservoirs, improve the experimental simulation accuracy, simplify the experimental operation process, greatly shorten the experimental period, reduce the consumption of experimental samples, and through this method, the plugging and profile control process and effect of steam and plugging agent particles can be directly observed, which can better simulate the experimental research on particle plugging and profile control after steam channeling in heavy oil reservoirs.

[0066] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, characterized in that, using a system for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics, the system for simulating steam channeling plugging and profile control in heavy oil reservoirs includes two etched transparent dielectric sheets with pore structures for reflecting steam channeling dominant channels in the middle, arranged on a heating device. The injection parts of the etched transparent dielectric sheets are connected to a steam generating device, an oil storage device, and a particle suspension storage device. The other ends of the oil storage device and the particle suspension storage device are commonly connected to a first displacement device, the other end of the steam generating device is connected to a second displacement device, the oil production part of the etched transparent dielectric sheet is connected to a liquid production collection device, and an image acquisition device is arranged above. The image acquisition device and the heating device are commonly electrically connected to a data acquisition and analysis device, including: Setting the temperature of the heating device to the formation temperature and placing the etched transparent dielectric sheet on the heating device; Injecting heavy oil into the oil storage device, using the first displacement device to displace the oil storage device to saturate the oil sample in the injection part of the etched transparent dielectric sheet, and turning on the image acquisition device; Using the second displacement device to inject the steam generated by the steam generating device into the etched transparent dielectric sheet until the water cut of the produced liquid reaches a preset threshold and then stopping; Using the first displacement device to displace the particle suspension storage device to inject a particle suspension with a preset multiple of the pore volume into the etched transparent dielectric sheet; Using the second displacement device again to inject the steam generated by the steam generating device into the etched transparent dielectric sheet until the water cut of the produced liquid reaches a preset threshold and then stopping; Using the data acquisition and analysis device to record the microscopic images, injection speed, and injection time during the displacement process collected by the image acquisition device, and record the water production volume in the liquid production collection device; Calculating different injection pore volume multiples using the injection speed, injection time, and total pore volume of the etched transparent dielectric sheet to obtain a relationship curve between the injection speed and the injection pore volume multiple; Calculating the recovery factor through the total saturated oil volume in the etched transparent dielectric sheet and the oil saturation corresponding to different injection pore volume multiples to obtain a relationship curve between the recovery factor and the injection pore volume multiple, and analyzing the oil production effect of steam channeling plugging and profile control in heavy oil reservoirs; Calculating the water cut through the total saturated oil volume, recovery factor, and water production volume in the etched transparent dielectric sheet to obtain a relationship curve between the water cut and the injection pore volume multiple.

2. The method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics according to claim 1, characterized in that, A pressure sensor is further arranged at the front end of the injection part of the etched transparent dielectric sheet, and the pressure sensor is electrically connected to the data acquisition and analysis device.

3. The method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics according to claim 1, characterized in that, A flow sensor is further arranged at the front end of the injection part of the etched transparent dielectric sheet, and the flow sensor is electrically connected to the data acquisition and analysis device.

4. The method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics according to claim 1, characterized in that, the image acquisition device is an electron microscope.

5. The method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics according to claim 4, characterized in that, it further includes a light source device arranged facing the etched transparent medium sheet.

6. The method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics according to claim 1, characterized in that, the etched transparent medium sheet is an etched glass sheet.

7. The method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics according to claim 1, characterized in that, the first displacement device includes a micro displacement pump that is connected to both the oil storage device and the particle suspension storage device, and a micro compressor connected to the other end of the micro displacement pump.

8. The method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics according to claim 1, characterized in that, the second displacement device is a high-precision displacement pump.

9. The method for simulating steam channeling plugging and profile control in heavy oil reservoirs based on microfluidics according to claim 1, characterized in that, the heating device is a heating plate with the temperature set to the formation temperature.

Images