Visual experiment method and system for multiphase microcosmic action mechanism

Abstract

The invention provides a visual experiment method and system for a multiphase microcosmic action mechanism. The visual experiment method comprises the following steps: S1, acquiring porous structure parameters of a rock sample; s2, manufacturing a hole network chip according to the porous structure parameters of the rock sample; s3, a thickened oil multiphase displacement visualization experiment system is built; s4, a thickened oil displacement experiment is carried out, and experiment data are collected; and S5, processing and analyzing the experimental data. The method is used for studying the microcosmic phase distribution characteristics and temperature distribution characteristics of the fluid in the heavy oil reservoir, further exploring the microcosmic mechanism of the fluid movement of the reservoir, and providing a practical visual experimental method for studying the oil displacement mechanism of heavy oil multi-element thermal compounding development.

Description

Technical Field

[0001] The invention relates to the technical field of oilfield development, and in particular to a visualization experimental method and system for a multiphase microscopic action mechanism. Background Art

[0002] China has abundant heavy oil resources, which are mainly distributed in Liaohe, Xinjiang, Shengli, Tahe, Tuha and other oilfield blocks. At present, most heavy oil reservoirs have entered the middle and late stages of steam stimulation or steam flooding. Steam stimulation and other displacement methods often require the injection of high-temperature and high-pressure gas into the oilfield. At present, the microscopic mechanism of this process is still unclear, so there are few related calculation models, which affects the improvement of oil recovery efficiency. Experimental methods that can study the coupling effect of phase migration and temperature distribution during displacement are becoming more and more important. Summary of the invention

[0003] In view of the above problems, the present invention is proposed to provide a visualization experimental method and system for multi-phase microscopic action mechanism that overcomes the above problems or at least partially solves the above problems.

[0004] According to one aspect of the present invention, a visualization experimental method for a multiphase microscopic action mechanism is provided, the visualization experimental method comprising:

[0005] Step S1: Obtaining porous structure parameters of rock samples;

[0006] Step S2: making a pore network chip according to the porous structure parameters of the rock sample;

[0007] Step S3: Building a visualization experimental system for heavy oil multiphase displacement;

[0008] Step S4: conducting a heavy oil displacement experiment and collecting experimental data;

[0009] Step S5: Processing and analyzing the experimental data.

[0010] Optionally, the step S1: obtaining the porous structure parameters of the rock sample specifically includes:

[0011] Use CT scanning technology to obtain tomographic images of rock samples;

[0012] The central axis extraction algorithm is used to obtain the porosity, pore size distribution curve, and throat size distribution curve of the sample to obtain the spatial structure information of the porous medium.

[0013] Optionally, the step S2: making a pore network chip according to the porous structure parameters of the rock sample specifically includes:

[0014] Designing the pore distribution structure of the pore network according to the sample structure information obtained in step S1;

[0015] The designed hole network channel is etched into the chip formed by bonding two layers of glass using laser etching technology.

[0016] Optionally, the step S3: building a heavy oil multiphase displacement visualization experimental system specifically includes:

[0017] The experimental system places a microscopic camera and a thermal imager on both sides of the pore network chip, and simultaneously collects the phase distribution and temperature distribution of the heavy oil to provide data support for analyzing the microscopic action mechanism.

[0018] Optionally, the step S4: performing a heavy oil displacement experiment and collecting experimental data specifically includes:

[0019] During the experiment, pure water was first injected into the pipeline. After the pore network chip was filled with pure water, heavy oil was injected into the pipeline to make the heavy oil and pure water in the pore network chip reach the set saturation.

[0020] Gas is injected into the pipeline to displace the oil-water mixture in the pore network chip, and the phase distribution and temperature distribution of the heavy oil are collected using a microscopic camera and a thermal imager.

[0021] Optionally, the step S5: processing and analyzing the experimental data specifically includes:

[0022] The time-lapse images reflect the dynamic changes in phase and temperature distribution in the pore network chip;

[0023] Extract the boundaries of the phase distribution image, obtain the volumes of the gas phase, liquid phase, and oil phase in the pore network chip, and calculate the change rate of each phase during the displacement process;

[0024] The phase distribution picture is compared with the temperature distribution picture, and the relationship between the migration of each phase and the temperature change is jointly analyzed.

[0025] Optionally, the equivalent pore network of the central axis extraction algorithm is constructed based on a tomographic image obtained by CT scanning of a rock sample.

[0026] Optionally, the visualization experiment system specifically includes: a high-pressure injection module, a low-pressure displacement module, a temperature control module and a microscopic observation module.

[0027] Optionally, the heavy oil multiphase displacement visualization experimental system uses an inserted temperature sensor arranged at the entrance of the microscopic observation platform to measure the temperature of the gas entering the pore network chip;

[0028] Two pressure sensors are set in the pipelines before and after the microscope observation platform to record the pressure data.

[0029] Optionally, in step S4: performing a heavy oil displacement experiment, during the process of collecting experimental data, a microscope camera and a thermal imager are placed on both sides of the microscope observation platform to record the phase distribution and temperature distribution in the pore network chip during the experiment from the upper and lower directions.

[0030] Optionally, the step S5: extracting the boundary of the phase distribution image in the processing and analysis of the experimental data specifically includes:

[0031] Use median filtering to remove noise from the image;

[0032] The Sobel operator is used to perform edge detection on the filtered image to obtain the boundaries of the gas phase, liquid phase, and oil phase;

[0033] According to the pixel coordinates of the boundary points, the area occupied by each phase is calculated, and the displacement migration rate of each phase during the displacement process is calculated.

[0034] The present invention also provides a visualization experiment system of a multiphase microscopic action mechanism, which uses the visualization experiment method of a multiphase microscopic action mechanism described above, and the visualization experiment system specifically comprises:

[0035] A structural parameter acquisition module is used to obtain porous structural parameters of rock samples;

[0036] A pore network chip manufacturing module, used for manufacturing a pore network chip according to the porous structure parameters of the rock sample;

[0037] Experimental system building module, used to build a heavy oil multiphase displacement visualization experimental system;

[0038] Experimental data acquisition module, used to conduct heavy oil displacement experiments and collect experimental data;

[0039] The data processing and analysis module is used to process and analyze the experimental data.

[0040] The present invention provides a visualization experimental method and system for multiphase microscopic action mechanism, the visualization experimental method comprising: step S1: obtaining porous structure parameters of rock samples; step S2: making pore network chips according to the porous structure parameters of rock samples; step S3: building a visualization experimental system for multiphase displacement of heavy oil; step S4: conducting heavy oil displacement experiments and collecting experimental data; step S5: processing and analyzing the experimental data. It is used to study the microscopic phase distribution characteristics and temperature distribution characteristics of fluids in heavy oil reservoirs, and then explore the microscopic mechanism of reservoir fluid movement, providing a practical visualization experimental method for the study of heavy oil multi-element thermal composite development and oil displacement mechanism.

[0041] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0043] Figure 1 A flow chart of a visual experimental method for a multiphase microscopic action mechanism provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0045] The terms "comprises" and "having" and any variations thereof in the description embodiments, claims and drawings of the present invention are intended to cover non-exclusive inclusions, for example, including a series of steps or units.

[0046] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0047] like Figure 1 As shown, a visualization experimental method for the multiphase microscopic action mechanism includes:

[0048] Step 101: extract parameter characteristics of the rock porous structure based on the CT scan image of the rock sample.

[0049] Step 102, using the sample structure information obtained in step 101 for designing a pore network structure, and etching the pore network on a glass chip, so that the phase distribution and temperature distribution during the heavy oil displacement process can be easily observed using a microscopic observation device and a thermal imager.

[0050] Step 103, build a visualization experimental system for multiphase displacement of heavy oil, arrange an inserted temperature sensor at the entrance of the microscopic observation platform to measure the temperature of the gas entering the pore network chip; set two pressure sensors in the pipelines before and after the microscopic observation platform to record pressure data; place a microscopic camera and a thermal imager on both sides of the pore network chip opposite to each other, and collect the phase distribution and temperature distribution of the heavy oil at the same time to provide data support for analyzing the microscopic action mechanism.

[0051] Step 104 , performing a heavy oil multiphase displacement experiment, and collecting the phase distribution and temperature distribution of the heavy oil using a microscopic camera and a thermal imager.

[0052] Step 105, extracting the boundaries of the experimental images, obtaining the dynamic change process of each phase during the displacement process, and jointly analyzing it with the temperature distribution change process to obtain the interaction relationship between phase movement and temperature change.

[0053] The present invention designs a pore network chip based on the pore structure information of the rock sample, and obtains the phase distribution and temperature distribution in the displacement process through a displacement visualization experimental system. It can be used to study the microscopic phase distribution characteristics and temperature distribution characteristics of the fluid in the heavy oil reservoir, and then explore the microscopic mechanism of reservoir fluid movement, thereby providing a practical visualization experimental method for the study of the heavy oil multi-element thermal composite development oil displacement mechanism.

[0054] The purpose of the present invention can be achieved by the following technical measures: a visualization experimental method for the microscopic mechanism of heavy oil multi-element thermal composite development, the method comprising:

[0055] Step 1: Obtain the porous structure parameters of the rock sample. Use CT scanning technology to obtain the tomographic image of the rock sample, and use the central axis extraction algorithm to obtain the spatial structure information of the porous medium such as the porosity, pore size distribution curve, and throat size distribution curve of the sample.

[0056] Step 2: Make a pore network chip. Design the pore distribution structure of the pore network based on the sample structure information obtained in step 1, and etch the designed pore network channel into the chip formed by bonding two layers of glass using laser etching technology.

[0057] Step 3: Build a visualization experimental system for multiphase displacement of heavy oil. Place an insertable temperature sensor at the entrance of the microscopic observation platform to measure the temperature of the gas entering the pore network chip. Set up two pressure sensors in the pipelines before and after the microscopic observation platform to record pressure data. Place the microscopic camera and thermal imager on both sides of the pore network chip opposite to each other, and collect the phase distribution and temperature distribution of the heavy oil at the same time to provide data support for the analysis of the microscopic action mechanism.

[0058] Step 4: Conduct a heavy oil multiphase displacement experiment and collect the phase distribution and temperature distribution of the heavy oil using a microscope camera and a thermal imager.

[0059] Step 5: Post-processing and analysis of experimental data. The time-lapse images reflect the dynamic changes in the phase distribution and temperature distribution in the pore network chip. The boundary of the phase distribution image is extracted to obtain the volume of the gas phase, liquid phase and oil phase in the pore network chip, and the change rate of each phase during the displacement process is calculated based on this. The phase distribution image is compared with the temperature distribution image to jointly analyze the relationship between the migration of each phase and the temperature change.

[0060] In step 1, the equivalent pore network of the extraction algorithm is constructed based on the tomographic images obtained by CT scanning of the rock samples.

[0061] In step 2, the sample structure information obtained in step 1 is used to design the pore network structure, and the pore network is etched on a glass chip. The resulting pore network chip is light-transmissive and can be easily used with a microscopic observation device and a thermal imager to observe the phase distribution and temperature distribution during the heavy oil displacement process.

[0062] In step 3, a visualization experimental system for multiphase displacement of heavy oil is built. An inserted temperature sensor is arranged at the entrance of the microscopic observation platform to measure the temperature of the gas entering the pore network chip. Two pressure sensors are set in the pipelines before and after the microscopic observation platform to record pressure data. The microscopic camera and thermal imager are placed opposite to each other on both sides of the pore network chip to collect the phase distribution and temperature distribution of the heavy oil at the same time to provide data support for the analysis of the microscopic action mechanism.

[0063] In step 4, a heavy oil multiphase displacement experiment is carried out, and the phase distribution and temperature distribution of the heavy oil are collected using a microscopic camera and a thermal imager.

[0064] In step 5, the boundary extraction of the phase distribution image first uses the median filter method to remove the noise in the image. Then the Sobel operator is used to detect the edge of the filtered image to obtain the boundaries of the gas phase, liquid phase and oil phase. Finally, according to the pixel coordinates of the boundary points, the area occupied by each phase is calculated, and then the displacement migration rate of each phase during the displacement process is calculated.

[0065] The experimental method of the present invention designs a pore network chip according to the pore structure information of the rock sample, and obtains the phase distribution and temperature distribution in the displacement process through a displacement visualization experimental system, which is used to study the microscopic phase distribution characteristics and temperature distribution characteristics of the fluid in the heavy oil reservoir, and then explore the microscopic mechanism of reservoir fluid movement, thereby providing a practical visualization experimental method for the study of the heavy oil multi-element thermal composite development oil displacement mechanism.

[0066] Beneficial effects: The present invention is used to study the microscopic phase distribution characteristics and temperature distribution characteristics of fluids in heavy oil reservoirs, explore the microscopic mechanism of reservoir fluid movement, and provide a practical visualization experimental method for the study of heavy oil multiphase development and oil displacement mechanism. The present invention fully considers the characteristics of heavy oil reservoirs and provides an experimental research method for the microscopic mechanism of heavy oil multiphase development, which has the advantages of low experimental cost and the ability to jointly observe phase distribution and temperature distribution.

[0067] The above specific implementation methods further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific implementation methods of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A visualization experimental method for multiphase microscopic action mechanism, characterized in that: The visualization experimental method comprises: Step S1: Obtaining porous structure parameters of rock samples; Step S2: making a pore network chip according to the porous structure parameters of the rock sample; Step S3: Building a visualization experimental system for heavy oil multiphase displacement; Step S4: conducting a heavy oil displacement experiment and collecting experimental data; Step S5: Processing and analyzing the experimental data.

2. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: The step S1: obtaining the porous structure parameters of the rock sample specifically includes: Use CT scanning technology to obtain tomographic images of rock samples; The central axis extraction algorithm is used to obtain the porosity, pore size distribution curve, and throat size distribution curve of the sample to obtain the spatial structure information of the porous medium.

3. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: The step S2: making a pore network chip according to the porous structure parameters of the rock sample specifically includes: Designing the pore distribution structure of the pore network according to the sample structure information obtained in step S1; The designed hole network channel is etched into the chip formed by bonding two layers of glass using laser etching technology.

4. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: The step S3: constructing a visual experimental system for heavy oil multiphase displacement specifically includes: The experimental system places a microscopic camera and a thermal imager on both sides of the pore network chip, and simultaneously collects the phase distribution and temperature distribution of the heavy oil to provide data support for analyzing the microscopic action mechanism.

5. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: The step S4: performing a heavy oil displacement experiment and collecting experimental data specifically includes: During the experiment, pure water was first injected into the pipeline. After the pore network chip was filled with pure water, heavy oil was injected into the pipeline to make the heavy oil and pure water in the pore network chip reach the set saturation. Gas is injected into the pipeline to displace the oil-water mixture in the pore network chip, and the phase distribution and temperature distribution of the heavy oil are collected using a microscopic camera and a thermal imager.

6. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: The step S5: processing and analyzing the experimental data specifically includes: The time-lapse images reflect the dynamic changes in phase and temperature distribution in the pore network chip; Extract the boundaries of the phase distribution image, obtain the volumes of the gas phase, liquid phase, and oil phase in the pore network chip, and calculate the change rate of each phase during the displacement process; The phase distribution picture is compared with the temperature distribution picture, and the relationship between the migration of each phase and the temperature change is jointly analyzed.

7. The method for visualizing a multiphase microscopic mechanism of action according to claim 2, characterized in that: The equivalent pore network of the central axis extraction algorithm is constructed based on the tomographic images obtained by CT scanning of rock samples.

8. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: The visualization experiment system specifically includes: a high-pressure injection module, a low-pressure displacement module, a temperature control module and a microscopic observation module.

9. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: The heavy oil multiphase displacement visualization experimental system uses an inserted temperature sensor arranged at the entrance of the microscopic observation platform to measure the temperature of the gas entering the pore network chip; Two pressure sensors are set in the pipelines before and after the microscope observation platform to record the pressure data.

10. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: Step S4: During the heavy oil displacement experiment and the experimental data collection process, a microscopic camera and a thermal imager are placed on both sides of the microscopic observation platform to record the phase distribution and temperature distribution in the pore network chip during the experiment from the upper and lower directions.

11. The method for visualizing a multiphase microscopic mechanism of action according to claim 1, characterized in that: The step S5: extracting the boundary of the phase distribution image in the processing and analysis of the experimental data specifically includes: Use median filtering to remove noise from the image; The Sobel operator is used to perform edge detection on the filtered image to obtain the boundaries of the gas phase, liquid phase, and oil phase; According to the pixel coordinates of the boundary points, the area occupied by each phase is calculated, and the displacement migration rate of each phase during the displacement process is calculated.

12. A visualization experimental system for multi-phase microscopic action mechanism, using a visualization experimental method for multi-phase microscopic action mechanism as described in any one of claims 1 to 11, characterized in that: The visualization experiment system specifically includes: A structural parameter acquisition module is used to obtain porous structural parameters of rock samples; A pore network chip manufacturing module, used for manufacturing a pore network chip according to the porous structure parameters of the rock sample; Experimental system building module, used to build a heavy oil multiphase displacement visualization experimental system; Experimental data acquisition module, used to conduct heavy oil displacement experiments and collect experimental data; The data processing and analysis module is used to process and analyze the experimental data.

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