Test method and test system for simulating exploitation of shale oil

Abstract

The present application provides a kind of test method and test system for simulating exploitation of shale oil.The test method for simulating exploitation of shale oil comprises: step S100: measuring the quality of reservoir core sample, and sealing and fixing the reservoir core sample;step S200: performing acoustic wave vibration on the reservoir core sample for a preset time length, and obtaining the acoustic wave attribute parameters of the reservoir core sample;step S300: under constant temperature environment, microwave radiation heating is performed on the reservoir core sample to a preset temperature, and maintained for a first preset time length;step S400: injecting supercritical carbon dioxide into the reservoir core sample, and stewing well for a second preset time length to carry out oil and gas exploitation;step S500: collecting the decomposition products of the reservoir core sample, and recording the cumulative production of the decomposition products.The present application solves the problem that the exploitation rule and recovery efficiency of shale oil in the prior art are difficult to evaluate effectively, resulting in high difficulty and low recovery efficiency in shale oil exploitation.

Description

Technical Field

[0001] This invention relates to the field of shale oil extraction technology, and more specifically, to a test method and test system for simulating shale oil extraction. Background Technology

[0002] Shale oil refers to liquid hydrocarbons that exist in organic-rich mudstone and shale formations in various forms, including free, adsorbed, and dissolved states. These mudstone and shale formations are the source rocks for the generation of liquid hydrocarbons and may still be in an oil-generating state. They are typical self-generated and self-storing in-situ oil and gas accumulation types.

[0003] In existing technologies, shale oil extraction is difficult, has a low recovery rate, and severely damages the ecological environment and water quality during extraction, resulting in significant limitations in the extraction process. Summary of the Invention

[0004] The main objective of this invention is to provide a test method and system for simulating shale oil extraction, in order to solve the problem that the extraction patterns and recovery rates of shale oil are difficult to evaluate effectively in the existing technology, resulting in high extraction difficulty and low recovery rates.

[0005] To achieve the above objectives, according to one aspect of the present invention, a test method for simulating shale oil extraction is provided, comprising: step S100: measuring the mass of a reservoir core sample and sealing and fixing the reservoir core sample; step S200: subjecting the reservoir core sample to acoustic vibration for a preset duration and obtaining the acoustic property parameters of the reservoir core sample; step S300: subjecting the reservoir core sample to microwave radiation heating to a preset temperature under constant temperature environment and maintaining it for a first preset duration; step S400: injecting supercritical carbon dioxide into the reservoir core sample and shutting the well for a second preset duration to perform oil and gas extraction; and step S500: collecting the decomposition products of the reservoir core sample and recording the cumulative yield of the decomposition products.

[0006] Furthermore, the experimental method also includes: before measuring the mass of the reservoir core sample, step S110: collecting shale oil reservoir cores and sealing them for preservation, and obtaining the formation temperature at the shale oil reservoir core collection location; step S120: conducting a pyrolysis test on the shale oil reservoir cores to obtain the pyrolysis parameters of the shale oil reservoir cores; step S130: conducting an acoustic vibration test on the shale oil reservoir cores to obtain the natural frequency of the shale oil reservoir cores; and step S140: cutting, polishing, and grinding the shale oil reservoir cores under liquid nitrogen conditions.

[0007] Furthermore, the experimental method also includes: repeating step S400, or steps S300 and S400, wherein in step S500, recording the cumulative yield of the decomposition products includes:

[0008] Calculate the total amount of oil, Mo′, in the decomposition products:

[0009] Calculate the total amount of water Mw′ in the decomposition products:

[0010] Calculate the total amount of gas V′ in the decomposition products:

[0011] in, Let be the mass of the oil obtained in the j-th carbon dioxide huff and puff test under the i-th microwave radiation test; Let be the mass of water obtained in the j-th carbon dioxide ionization test under the i-th microwave radiation test; Let be the volume of gas obtained in the j-th carbon dioxide ionization test under the i-th microwave radiation test; i is the number of microwave radiation tests, n is the total number of microwave radiation tests; j is the number of carbon dioxide ionization tests, and m is the total number of carbon dioxide ionization tests.

[0012] Further, in step S500, collecting the decomposition products of the reservoir core sample includes: cooling the decomposition products to cool the oil and water in the decomposition products, and centrifuging the cooled oil and water to separate them; removing the carbon dioxide mixed in the decomposition products, and collecting the gas in the decomposition products.

[0013] According to another aspect of the present invention, a test system for simulating shale oil extraction is provided, comprising a microwave radiation device, a clamping device, an acoustic vibration device, an ultrasonic measuring device, a supercritical carbon dioxide supply device, and an oil-water-gas collection device. The clamping device is disposed within the microwave radiation device. The acoustic vibration device and the ultrasonic measuring device are detachably connected to the clamping device, respectively. The supercritical carbon dioxide supply device is connected to the clamping device, and the oil-water-gas collection device is connected to the clamping device.

[0014] Furthermore, the clamping device includes a first pump body, a first container, a clamp, and a sealing sleeve. The first pump body, the first container, and the clamp are connected in sequence. A first valve is provided between the first container and the clamp. The first container is used to store nitrogen gas and injects nitrogen gas into the clamp through the first pump body to provide ring pressure. The sealing sleeve is provided inside the clamp and is used to seal the reservoir core sample.

[0015] Furthermore, the acoustic vibration device includes an acoustic generator, a power amplifier, and an acoustic transducer connected in sequence, with the acoustic transducer detachably connected to the outer wall of the clamp.

[0016] Furthermore, the ultrasonic measuring device includes an ultrasonic exciter, an oscilloscope, and an ultrasonic probe assembly. The ultrasonic probe assembly is detachably connected to the outer wall of the holder. The oscilloscope is connected to both the ultrasonic exciter and the terminal device. The ultrasonic probe assembly includes a transmitting probe and a receiving probe. The transmitting probe is connected to the ultrasonic exciter, and the receiving probe is connected to the oscilloscope.

[0017] Furthermore, the microwave radiation device includes a microwave generator, a microwave anechoic chamber, a microwave radiating plate, a thermocouple, and a temperature transmitter. The microwave generator is connected to the terminal equipment. The microwave radiating plate is installed in the microwave anechoic chamber and connected to the microwave generator. The thermocouple is installed in the microwave anechoic chamber and connected to the temperature transmitter. The temperature transmitter is connected to the terminal equipment.

[0018] Furthermore, the supercritical carbon dioxide supply device includes a second pump body, a second container, and a constant temperature chamber. The second pump body, the second container, and the clamp are connected in sequence. A four-way valve is provided between the second container and the clamp, and a vent valve is provided on the four-way valve. A second valve is provided between the second container and the four-way valve. A third valve and a pressure gauge are provided between the clamp and the four-way valve. The microwave anechoic chamber and the second container are located inside the constant temperature chamber.

[0019] Furthermore, the oil-water-gas collection device includes a cooling metering component, a carbon dioxide removal component, a flow meter, and a gas collection component connected in sequence. The cooling metering component is connected to a four-way valve, and a fourth valve and a back pressure valve are provided between the cooling metering component and the four-way valve.

[0020] By applying the technical solution of this invention, measuring the mass of reservoir core samples provides a basis for determining the volume of supercritical carbon dioxide injected into them. Sealing and fixing the reservoir core samples stabilizes the experimental process, avoids interference from the external environment, and improves the accuracy of the experimental data. By subjecting the reservoir core samples to ultrasonic vibration for a preset duration and obtaining their acoustic properties, the changes in pore structure and fracture formation under vibration excitation can be reflected, providing experimental data support for waterless fracturing of formations. Microwave heating of the reservoir core samples to a preset temperature under constant temperature conditions for a first preset duration ensures sufficient heating after vibration fracturing. Microwave heating induces molecular vibration during the heating process, promoting more complete decomposition reactions. Injecting supercritical carbon dioxide into the reservoir core samples for a second preset duration allows for sufficient diffusion and contact within the samples. By collecting decomposition products from reservoir core samples and recording their yield, different decomposition rates under different experimental conditions can be obtained. Based on the experimental data, experimental parameters, such as microwave radiation heating power and isothermal time, can be optimized. In the above experimental method, experimental parameters such as the first preset duration, the second preset duration, and the preset temperature can be set within a reasonable range. Based on this method, the extraction law and recovery rate of shale oil under the synergistic effect of microwave-supercritical carbon dioxide huff and puff can be obtained, thus providing necessary theoretical research and experimental basis for shale oil extraction, facilitating the optimization of shale oil extraction methods, and improving recovery rates. Attached Figure Description

[0021] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0022] Figure 1 A flowchart of the experimental method for simulating shale oil extraction according to the present invention is shown;

[0023] Figure 2 A schematic diagram of the experimental system for simulating shale oil extraction according to the present invention is shown.

[0024] The above figures include the following reference numerals:

[0025] 112. Microwave generator; 113. Microwave anechoic chamber; 114. Microwave radiating plate; 115. Thermocouple; 116. Temperature transmitter; 121. First pump body; 122. First container; 123. Clamp; 124. Sealing sleeve; 125. First valve; 132. Sound wave generator; 134. Power amplifier; 136. Sound wave transducer; 142. Ultrasonic exciter; 144. Oscilloscope; 146. Transmitting probe ; 148. Receiving probe; 151. Second pump body; 152. Second container; 153. Four-way valve; 154. Second valve; 155. Third valve; 156. Pressure gauge; 157. Thermostatic chamber; 159. Vent valve; 161. Cooling metering assembly; 162. Carbon dioxide removal assembly; 163. Flow meter; 164. Gas collection assembly; 165. Fourth valve; 166. Back pressure valve; 170. Terminal equipment. Detailed Implementation

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0028] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0029] To address the challenges of effectively evaluating the extraction patterns and recovery rates of shale oil in existing technologies, which leads to high extraction difficulty and low recovery rates, this invention provides a test method and system for simulating shale oil extraction.

[0030] like Figure 1 The method for simulating shale oil extraction includes: Step S100: Measuring the mass of a reservoir core sample and sealing and fixing it; Step S200: Performing acoustic vibration on the reservoir core sample for a preset duration and obtaining the acoustic property parameters of the reservoir core sample; Step S300: Heating the reservoir core sample to a preset temperature under constant temperature environment using microwave radiation and maintaining it for a first preset duration; Step S400: Injecting supercritical carbon dioxide into the reservoir core sample and simmering the well for a second preset duration to perform oil and gas extraction; Step S500: Collecting the decomposition products of the reservoir core sample and recording the cumulative yield of the decomposition products.

[0031] This embodiment measures the mass of reservoir core samples to provide a basis for determining the volume of supercritical carbon dioxide injected into them. Sealing and fixing the reservoir core samples stabilizes the experiment and avoids interference from the external environment, thus improving the accuracy of the experimental data. By subjecting the reservoir core samples to ultrasonic vibration for a preset duration and acquiring their acoustic properties, the changes in pore structure and fracture formation under vibration excitation can be reflected, providing experimental data support for waterless fracturing of formations. Microwave heating of the reservoir core samples to a preset temperature under constant temperature conditions and maintaining this temperature for a first preset duration ensures sufficient heating of the vibratory fracturing process. Microwave heating also induces molecular vibration during the heating process, promoting more complete decomposition reactions. Injecting supercritical carbon dioxide into the reservoir core samples and maintaining this injection for a second preset duration allows for sufficient diffusion of carbon dioxide within the samples, ensuring adequate contact. By collecting decomposition products from reservoir core samples and recording their yield, different decomposition rates under different experimental conditions can be obtained. Based on the experimental data, experimental parameters, such as microwave radiation heating power and isothermal time, can be optimized. In the above experimental method, experimental parameters such as the first preset duration, the second preset duration, and the preset temperature can be set within a reasonable range. Based on this method, the extraction law and recovery rate of shale oil under the synergistic effect of microwave-supercritical carbon dioxide huff and puff can be obtained, thus providing necessary theoretical research and experimental basis for shale oil extraction, facilitating the optimization of shale oil extraction methods, and improving recovery rates.

[0032] The following is a detailed explanation of each of the above steps:

[0033] S100. Measure the mass of the reservoir core sample and seal and fix the reservoir core sample.

[0034] Specifically, after measuring the mass of the reservoir core sample, the reservoir core sample can be placed in a temperature- and pressure-resistant rubber sleeve for sealing and fixed in a specific position, such as a clamp.

[0035] S200. Perform acoustic vibration on the reservoir core sample for a preset duration and obtain the acoustic property parameters of the reservoir core sample.

[0036] Specifically, the reservoir core samples are subjected to acoustic vibration excitation for a preset duration so that the acoustic parameters measured after the reservoir core samples are excited have certain reference value. Based on the acoustic property parameters, the changes in the pore structure and the formation of fractures in the reservoir core samples after excitation can be known. This is used to simulate the process of waterless fracturing to transform the formation and to provide experimental support for shale oil extraction.

[0037] During the experiment, the changes in pore structure and fracture formation of the reservoir core sample under vibration excitation can be reflected by measuring the first arrival time of the first wave and the amplitude of the waveform. That is, a longer first arrival time and a smaller amplitude indicate an increase in fractures in the reservoir core sample. This experimental process will simulate the formation stimulation process without water fracturing, providing necessary data for the advancement of actual mining.

[0038] S300, under constant temperature environment, the reservoir core sample is heated to the preset temperature by microwave radiation and maintained for the first preset time.

[0039] It should be noted that the constant temperature environment is used to simulate the temperature of the formation where the reservoir core sample is located, ensuring that the normal extraction of shale oil is not affected by formation temperature issues during actual shale oil reservoir development. Additionally, microwave radiation heating of the reservoir core sample, i.e., conducting a microwave radiation experiment, can cause vibration of the reservoir core sample during heating, which is beneficial for subsequent decomposition of the reservoir core sample. This preset temperature can be determined based on the pyrolysis characteristics of the obtained reservoir core sample, such as 300℃, and is maintained at this temperature for a first preset time to ensure that the reservoir core sample is fully heated. For example, this first preset time can be set to 20 minutes.

[0040] S400: Inject supercritical carbon dioxide into reservoir core samples and shut the well for a second preset time to carry out oil and gas extraction.

[0041] Specifically, the carbon dioxide pressure inside the carbon dioxide storage container can be made greater than the supercritical pressure of carbon dioxide, and supercritical carbon dioxide can be injected into the reservoir core sample. After injection, the carbon dioxide and the reservoir core sample are allowed to come into full contact in a sealed environment. This process continues for a second preset time, i.e., a carbon dioxide huff and puff test is conducted. For example, the second preset time can be set to 30 minutes to facilitate oil and gas extraction.

[0042] S500. Collect the decomposition products of reservoir core samples and record the cumulative yield of the decomposition products.

[0043] Specifically, the decomposition products include oil, gas, and water. By changing the temperature or time mentioned above and comparing the yield of the decomposition products, it is of great significance to determine the appropriate parameters for actual shale oil extraction based on experimental data.

[0044] In this embodiment, the test method further includes performing the following operations before measuring the mass of the reservoir core sample:

[0045] S110. Collect shale oil reservoir cores and seal them for preservation to obtain the formation temperature at the shale oil reservoir core collection location.

[0046] Specifically, in practice, high-quality shale oil reservoir sections can be identified based on geological, seismic, and well logging data. The collected shale oil reservoir cores are then sealed and preserved to prevent oxidation or other uncertainties from affecting the test results. When collecting shale oil reservoir cores, the target section being drilled needs to be cored in a sealed environment. During core collection, hydrocarbon loss must be minimized. After reaching the surface, the cores are wrapped in tin foil, sealed with wax, and stored in a low-temperature environment. A water-based sealing fluid is used, and it is crucial to prevent the sealing fluid from seeping into the shale oil reservoir core and affecting its quality. Simultaneously, the formation temperature at the core collection location is measured to simulate the formation temperature during subsequent tests. The formation temperature is determined by the formation depth of the shale oil reservoir. For example, the formation temperature is typically 110℃~130℃, with the actual measured temperature being the most accurate.

[0047] S120. Conduct pyrolysis tests on shale oil reservoir cores to obtain pyrolysis parameters of the shale oil reservoir cores.

[0048] Specifically, the pyrolysis temperature of the collected shale oil reservoir cores can be determined through pyrolysis tests. For example, the optimal pyrolysis temperature for shale oil reservoir cores is 300℃ to 500℃. Based on the measured pyrolysis parameters, subsequent heating of the reservoir core samples is conducted within a clearly defined heating range, avoiding indiscriminate heating that could affect the experimental process.

[0049] S130. Conduct acoustic vibration tests on shale oil reservoir cores to obtain the natural frequencies of the shale oil reservoir cores.

[0050] Specifically, by conducting acoustic vibration tests on the collected shale oil cores, the natural frequency of the shale oil reservoir cores can be obtained through the vibration waveforms of the cores. This allows for rapid destruction of the reservoir core samples in subsequent tests, saving testing time.

[0051] Shale oil reservoir core cutting, polishing and grinding under S140 and liquid nitrogen environment.

[0052] Specifically, liquid nitrogen environment can provide the necessary low temperature environment for shale oil reservoir core processing, avoiding excessively high local temperatures at the processing site of the shale oil reservoir core during cutting, polishing, and grinding, which would affect the quality of the shale oil core.

[0053] In this embodiment, the experimental method further includes: repeating step S400, or steps S300 and S400, to conduct multiple experiments. In step S500, recording the cumulative yield of the decomposition products includes:

[0054] Calculate the total amount of oil, Mo′, in the decomposition products:

[0055] Calculate the total amount of water Mw′ in the decomposition products:

[0056] Calculate the total amount of gas V′ in the decomposition products:

[0057] in, Let be the mass of the oil obtained in the j-th carbon dioxide huff and puff test under the i-th microwave radiation test; Let be the mass of water obtained in the j-th carbon dioxide ionization test under the i-th microwave radiation test; Let be the volume of gas obtained in the j-th carbon dioxide ionization test under the i-th microwave radiation test; i is the number of microwave radiation tests, n is the total number of microwave radiation tests; j is the number of carbon dioxide ionization tests, and m is the total number of carbon dioxide ionization tests.

[0058] To fully extract the decomposition products, step S400 can be repeated. When the extracted products no longer increase, steps S300 and S400 can be repeated, allowing the reservoir core sample to undergo radiation heating decomposition again. Then, supercritical carbon dioxide huff and puff experiments are used for product extraction, ultimately ensuring full decomposition and product extraction from the reservoir core sample. Based on the three formulas mentioned above, the total oil (Mo′), total water (Mw′), and total gas (V′) in the decomposition products are calculated. Analysis of the decomposition products reveals the extraction patterns and recovery rates of shale oil under different extraction conditions. This provides a basis for further optimization of microwave radiation power, the number of microwave radiation experiments, carbon dioxide injection volume, and carbon dioxide huff and puff frequency, thus providing the necessary theoretical research and experimental foundation for the microwave-supercritical carbon dioxide huff and puff co-production of shale oil.

[0059] In step S500, the collection of decomposition products from reservoir core samples includes: cooling the decomposition products to cool the oil and water in the decomposition products, and centrifuging the cooled oil and water to separate them; removing carbon dioxide mixed in the decomposition products, and collecting the gas in the decomposition products.

[0060] Specifically, the cooling medium required for condensation can be liquid nitrogen, ice, or a mixture of ice and water, etc. This embodiment does not impose specific limitations on this, as long as the required condensation conditions are met. When collecting the gas from the decomposition products, a flow meter can be installed on the gas collection pipeline after removing carbon dioxide to measure the volume of the generated gas.

[0061] It should be noted that the order in which the above experimental methods are described does not represent the order in which the experiments are conducted. The same experimental process may also be performed multiple times, and is not limited to the steps described in this embodiment. In addition, the above experimental methods can also be used to test oil shale reservoir samples, and the specific operations are the same as described above, so they will not be repeated here.

[0062] like Figure 2 As shown, this embodiment also provides a test system for simulating shale oil extraction, including a microwave radiation device, a clamping device, an acoustic vibration device, an ultrasonic measuring device, a supercritical carbon dioxide supply device, and an oil-water-gas collection device. The clamping device is installed inside the microwave radiation device. The acoustic vibration device and the ultrasonic measuring device are detachably connected to the clamping device. The supercritical carbon dioxide supply device is connected to the clamping device, and the oil-water-gas collection device is connected to the clamping device.

[0063] Specifically, the aforementioned experimental system is used in conjunction with the aforementioned experimental methods. During operation, the reservoir core sample is placed inside the clamping device, and a microwave radiation device heats the sample. Before heating, the reservoir core sample is vibrated using an acoustic vibration device. After vibration excitation, an ultrasonic measuring device is used to detect the acoustic properties of the reservoir core sample to understand changes in its pore structure, facilitating subsequent operational steps. A supercritical carbon dioxide supply device provides supercritical carbon dioxide to the reservoir core sample, and the final product is collected using an oil-water-gas collection device. The shale oil simulation system provided in this embodiment provides the necessary experimental environment for the aforementioned experimental methods, ensuring stable experimental execution, providing necessary hardware support for shale oil extraction, facilitating optimization of shale oil extraction methods, and improving the accuracy and reliability of experimental data. Furthermore, this shale oil simulation system can also be used to test oil shale samples using the aforementioned experimental methods, which will not be elaborated further here.

[0064] like Figure 2 As shown, the clamping device includes a first pump body 121, a first container 122, a clamp 123, and a sealing sleeve 124 disposed inside the clamp 123. The sealing sleeve 124 is used to seal the reservoir core sample. The first pump body 121, the first container 122, and the clamp 123 are connected in sequence. A first valve 125 is provided between the first container 122 and the clamp 123. The first container 122 is used to store nitrogen gas, and the nitrogen gas is injected into the clamp 123 through the first pump body 121 to provide annular pressure.

[0065] Specifically, the sealing sleeve 124 can be a rubber sleeve to seal the reservoir core sample, and the clamp 123 is made of a temperature- and pressure-resistant special engineering plastic, such as polyetheretherketone, polyimide, or polyphenylene ester. This material needs to meet the requirements of a maximum pressure of 30 MPa and a maximum temperature of 800°C to meet the needs of heating and pressurization. In this way, when nitrogen gas from the first container 122 is injected into the clamp 123 through the first pump body 121, it can support the pressure of the nitrogen gas. In addition, when the reservoir core sample is heated by a microwave radiation device, it can also withstand the heat of heating well, which helps to improve the stability of the clamp device during use.

[0066] It should be noted that the embodiments of the present invention do not impose specific limitations on the first pump body 121; for example, a hand-cranked pump or an electric pump can be used. Additionally, the first valve 125 is used to control the flow of nitrogen. After injecting nitrogen at a preset pressure, the first valve 125 can be closed to prevent nitrogen leakage along the channel. Furthermore, the acoustic vibration device, ultrasonic measuring device, supercritical carbon dioxide supply device, and oil-water-gas collection device are respectively connected to the clamp 123 of the clamping device to facilitate experimental operations on reservoir core samples.

[0067] like Figure 2 As shown, the acoustic vibration device includes an acoustic generator 132, a power amplifier 134 and an acoustic transducer 136 connected in sequence. The acoustic transducer 136 is detachably connected to the outer wall of the clamp 123.

[0068] Thus, during use, by turning on the acoustic generator 132 and adjusting the power amplifier 134, the reservoir core sample inside the clamping device can be excited by acoustic vibration. When performing microwave radiation heating, the acoustic transducer 136 can be temporarily removed to avoid damage from high temperatures.

[0069] like Figure 2 As shown, the ultrasonic measuring device includes an ultrasonic exciter 142, an oscilloscope 144, and an ultrasonic probe assembly. The oscilloscope 144 is connected to the ultrasonic exciter 142 and the terminal device 170, respectively. The ultrasonic probe assembly is detachably connected to the outer wall of the holder 123. The ultrasonic probe assembly includes a transmitting probe 146 and a receiving probe 148. The transmitting probe 146 is connected to the ultrasonic exciter 142, and the receiving probe 148 is connected to the oscilloscope 144.

[0070] Specifically, the transmitting probe 146 and the receiving probe 148 are located on both sides of the holder 123, and are used to monitor the arrival time and waveform of the first wave of the excited reservoir core sample inside the holder 123. After the required parameters are measured, the transmitting probe 146 and the receiving probe 148 can also be removed from the holder 123 to avoid damage from high temperatures during microwave radiation heating. In addition, the terminal device 170 can be a computer for convenient viewing, calculation, or statistical analysis of the parameters.

[0071] like Figure 2 As shown, the microwave radiation device includes a microwave generator 112, a microwave anechoic chamber 113, a microwave radiating plate 114, a thermocouple 115, and a temperature transmitter 116. The microwave radiating plate 114 is disposed in the microwave anechoic chamber 113 and connected to the microwave generator 112. The microwave generator 112 is connected to the terminal device 170. The thermocouple 115 is disposed in the microwave anechoic chamber 113 and connected to the temperature transmitter 116. The temperature transmitter 116 is connected to the terminal device 170.

[0072] Specifically, the microwave generator 112 heats the microwave anechoic chamber 113 through the microwave radiator 114, thereby heating the reservoir core sample inside the clamping device. Thermocouple 115 inside the microwave anechoic chamber 113 is connected to temperature transmitter 116, which in turn is connected to terminal device 170, so that the temperature information in the microwave anechoic chamber 113 can be fed back to the terminal device 170 for relevant operations based on the information.

[0073] like Figure 2 As shown, the supercritical carbon dioxide supply device includes a second pump body 151, a second container 152, and a constant temperature chamber 157. The second pump body 151, the second container 152, and the clamp 123 are connected in sequence. A four-way valve 153 is provided between the second container 152 and the clamp 123. A vent valve 159 is provided on the four-way valve 153. A second valve 154 is provided between the second container 152 and the four-way valve 153. A third valve 155 and a pressure gauge 156 are provided between the clamp 123 and the four-way valve 153. The microwave anechoic chamber 113 and the second container 152 are located inside the constant temperature chamber 157.

[0074] Specifically, this embodiment of the invention does not impose specific limitations on the second pump body 151. For example, the second pump body 151 can be a high-precision displacement pump to provide supercritical carbon dioxide. When providing supercritical carbon dioxide to the reservoir core sample in the holder 123, the vent valve 159 must first be opened to purge the air in the pipeline, and then the third valve 155 must be opened to provide supercritical carbon dioxide. Additionally, the constant temperature chamber 157 is used to provide the temperature of the environment in which the reservoir core sample is located. This ensures that the normal extraction of shale oil is not affected by formation temperature issues during actual shale oil extraction.

[0075] like Figure 2 As shown, the oil, water and gas collection device includes a cooling metering component 161, a carbon dioxide removal component 162, a flow meter 163 and a gas collection component 164 connected in sequence. The cooling metering component 161 is connected to a four-way valve 153. A fourth valve 165 and a back pressure valve 166 are provided between the cooling metering component 161 and the four-way valve 153.

[0076] Specifically, during the collection of decomposition products, both the second valve 154 and the vent valve 159 are closed. At this time, the decomposition products flow through the third valve 155, the fourth valve 165, and the back pressure valve 166, passing through the cooling metering assembly 161, the carbon dioxide removal assembly 162, and the flow meter 163. The final generated gas is collected by the gas collection assembly 164. The cooling metering assembly 161 consists of a test tube and a cooling medium, such as liquid nitrogen, ice, or an ice-water mixture. The generated gas and carbon dioxide pass through the cooling metering assembly 161 to the carbon dioxide removal assembly 162. An alkaline solution, such as sodium hydroxide solution, can be used to absorb the carbon dioxide. The total flow rate and volume of the absorbed gas can be measured by the flow meter 163, and the produced gas is collected by the gas collection assembly 164. For component analysis of the collected decomposition products, a gas chromatograph can be used to detect whether the carbon dioxide has been completely removed and to identify specific components in the gas, such as methane and ethane.

[0077] It should be noted that "multiple" in the above embodiments refers to at least two.

[0078] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0079] 1. It solves the problem that the extraction patterns and recovery rates of shale oil are difficult to evaluate effectively in existing technologies, resulting in high extraction difficulty and low recovery rates for shale oil;

[0080] 2. Based on the experimental method, the extraction law and recovery rate of shale oil under the synergistic effect of microwave-supercritical carbon dioxide huff and puff can be obtained, thus providing the necessary theoretical research and experimental basis for shale oil extraction, facilitating the optimization of shale oil extraction methods and improving the recovery rate;

[0081] 3. The test system provides the necessary test environment for the test method, which helps to ensure the stable conduct of the test, provides the necessary hardware support for shale oil extraction, facilitates the optimization of shale oil extraction methods, and improves the accuracy and reliability of test data.

[0082] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0083] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0084] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0085] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A test method for simulating shale oil extraction, characterized in that, include: Step S100: Measure the mass of the reservoir core sample and seal and fix the reservoir core sample; Step S200: Perform acoustic vibration on the reservoir core sample for a preset duration and obtain the acoustic property parameters of the reservoir core sample; Step S300: The reservoir core sample is heated to a preset temperature by microwave radiation under constant temperature environment and maintained for a first preset time; Step S400: Inject supercritical carbon dioxide into the reservoir core sample and shut the well for a second preset time to carry out oil and gas extraction; Step S5 00: Collect the decomposition products of the reservoir core sample and record the cumulative yield of the decomposition products; The experimental method further includes: repeating step S400, or steps S300 and S400, wherein in step S500, recording the cumulative yield of the decomposition products includes: Calculate the total amount of oil (Mo') in the decomposition products: ; Calculate the total amount of water Mw in the decomposition products: ; Calculate the total amount of gas V' in the decomposition products: ; in, Let be the mass of the oil obtained in the j-th carbon dioxide huff and puff test under the i-th microwave radiation test; Let be the mass of water obtained in the j-th carbon dioxide ionization test under the i-th microwave radiation test; Let be the volume of gas obtained in the j-th carbon dioxide ionization test under the i-th microwave radiation test; i is the number of microwave radiation tests, n is the total number of microwave radiation tests; j is the number of carbon dioxide ionization tests, and m is the total number of carbon dioxide ionization tests. By analyzing the decomposition products, the extraction patterns and recovery rates of shale oil under different extraction conditions were obtained. Before measuring the mass of the reservoir core sample. Step S110: Collect shale oil reservoir cores and seal them for preservation, and obtain the formation temperature at the core collection location of the shale oil reservoir; Step S120: Conduct a pyrolysis test on the shale oil reservoir core to obtain the pyrolysis parameters of the shale oil reservoir core; Step S130: Conduct an acoustic vibration test on the shale oil reservoir core to obtain the natural frequency of the shale oil reservoir core; Step S140: The shale oil reservoir core is cut, polished, and ground in a liquid nitrogen environment; In step S500, the decomposition products collected from the reservoir core sample include: The decomposition products are cooled to cool the oil and water in the decomposition products, and the cooled oil and water are separated by centrifugation. After removing the carbon dioxide mixed in the decomposition products, the gas in the decomposition products is collected.

2. A test system for simulating shale oil extraction, employing the test method for simulating shale oil extraction as described in claim 1, characterized in that, The experimental system includes a microwave radiation device, a clamping device, an acoustic vibration device, an ultrasonic measuring device, a supercritical carbon dioxide supply device, and an oil, water, and gas collection device. The clamping device is located inside the microwave radiation device. The acoustic vibration device and the ultrasonic measuring device are detachably connected to the clamping device. The supercritical carbon dioxide supply device is connected to the clamping device, and the oil, water, and gas collection device is connected to the clamping device.

3. The testing system according to claim 2, characterized in that, The clamping device includes a first pump body (121), a first container (122), a clamp (123), and a sealing sleeve (124). The first pump body (121), the first container (122), and the clamp (123) are connected in sequence. A first valve (125) is provided between the first container (122) and the clamp (123). The first container (122) is used to store nitrogen gas, and the nitrogen gas is injected into the clamp (123) through the first pump body (121) to provide ring pressure. The sealing sleeve (124) is disposed in the clamp (123) and is used to seal the reservoir core sample.

4. The testing system according to claim 3, characterized in that, The acoustic vibration device includes an acoustic generator (132), a power amplifier (134), and an acoustic transducer (136) connected in sequence. The acoustic transducer (136) is detachably connected to the outer wall of the clamp (123).

5. The testing system according to claim 3, characterized in that, The ultrasonic measuring device includes an ultrasonic exciter (142), an oscilloscope (144), and an ultrasonic probe assembly. The ultrasonic probe assembly is detachably connected to the outer wall of the holder (123). The oscilloscope (144) is connected to the ultrasonic exciter (142) and the terminal device (170) respectively. The ultrasonic probe assembly includes a transmitting probe (146) and a receiving probe (148). The transmitting probe (146) is connected to the ultrasonic exciter (142), and the receiving probe (148) is connected to the oscilloscope (144).

6. The testing system according to claim 3, characterized in that, The microwave radiation device includes a microwave generator (112), a microwave anechoic chamber (113), a microwave radiating plate (114), a thermocouple (115), and a temperature transmitter (116). The microwave generator (112) is connected to a terminal device (170). The microwave radiating plate (114) is located in the microwave anechoic chamber (113) and connected to the microwave generator (112). The thermocouple (115) is located in the microwave anechoic chamber (113) and connected to the temperature transmitter (116). The temperature transmitter (116) is connected to the terminal device (170).

7. The testing system according to claim 6, characterized in that, The supercritical carbon dioxide supply device includes a second pump body (151), a second container (152), and a constant temperature chamber (157). The second pump body (151), the second container (152), and the clamp (123) are connected in sequence. A four-way valve (153) is provided between the second container (152) and the clamp (123). A vent valve (159) is provided on the four-way valve (153). A second valve (154) is provided between the second container (152) and the four-way valve (153). A third valve (155) and a pressure gauge (156) are provided between the clamp (123) and the four-way valve (153). The microwave anechoic chamber (113) and the second container (152) are located inside the constant temperature chamber (157).

8. The testing system according to claim 7, characterized in that, The oil, water and gas collection device includes a cooling metering component (161), a carbon dioxide removal component (162), a flow meter (163) and a gas collection component (164) connected in sequence. The cooling metering component (161) is connected to the four-way valve (153). A fourth valve (165) and a back pressure valve (166) are provided between the cooling metering component (161) and the four-way valve (153).

Images