Simulation device and simulation method for full-sequence oil-gas accumulation process of full-oil-gas system

Abstract

The invention provides a simulation device and a simulation method for a full-sequence oil-gas accumulation process of a full-oil-gas system, and relates to the technical field of oil-gas accumulation. The simulation device comprises a fixed frame, a visual model, an angle adjusting frame, a pressurizing device and a drainage device; the visual model is placed on the fixed frame, the visual model is provided with a cavity for placing a stratum sample, and an angle adjusting frame is placed below the visual model so as to simulate different geological environments or experimental conditions; the stratum model is completely saturated with simulated stratum water through a displacement method; measuring basic physical property parameters of the formation model in a saturated formation water state; performing a simulation experiment through pressure filling and liquid adding, and recording experiment data; and analyzing experimental data to obtain pressure and liquid outlet data of oil gas during primary migration and secondary migration and high-definition photos of oil gas migration and accumulation processes and distribution characteristics, and accurately displaying the underground oil gas migration and accumulation process.

Description

Technical Field

[0001] The present invention relates to the technical field of oil and gas accumulation, and in particular to a simulation device and method for a full-sequence oil and gas accumulation process of a full oil and gas system. Background Art

[0002] The full petroleum system theory is a theory of oil and gas accumulation proposed in recent years based on the exploration of deep and ultra-deep oil and gas. While theoretical reconstructions of the entire oil and gas system's full sequence of accumulation have been achieved, experimental devices capable of simulating this full sequence are still lacking. Oil and gas migration, accumulation, and accumulation are complex processes governed by a variety of geological conditions. Studying this process is a crucial component of petroleum geology. By studying fundamental processes such as conventional and unconventional oil and gas generation, migration, and accumulation, we can understand the conditions, influencing processes, and dynamic mechanisms of oil and gas accumulation. Over the years, physical simulation experiments have flourished and have been widely applied in oil and gas reservoir research. These experiments allow for the intuitive reflection of oil and gas migration, accumulation, and simulating dominant oil and gas migration pathways through physical simulation models under laboratory conditions.

[0003] Despite the continuous development of simulation methods, equipment improvements, and the increasing number of elements, many problems remain: ① The limited physical properties of oil and gas reservoirs make it difficult to capture changes in reservoir properties and to reconstruct the full sequence of reservoir formation. ② Subtle phenomena of oil and gas filling and migration are not readily apparent, making observation difficult. ③ The limited observation area makes parameter determination difficult. These issues hinder the applicability of physical simulation of oil and gas accumulation and hinder a comprehensive understanding of the processes and mechanisms of oil and gas filling, migration, accumulation, and reservoir formation. Summary of the Invention

[0004] To address the above issues, this design invention addresses some of the shortcomings of traditional two-dimensional physical simulation methods and designs a simulation method for the entire oil and gas system and the entire sequence of oil and gas accumulation processes, including: Step 1: Connect and debug the simulation device for the entire oil and gas system and the entire sequence of oil and gas accumulation process; Step 2: preparing a solution for a simulation experiment; Step 3: Build a stratum model; Step 4: Fully saturate the formation model with simulated formation water through displacement method; Step 5: Determine the basic physical parameters of the formation model under the state of saturated formation water; Step 6: Conduct simulation experiments by filling pressure and adding liquid, and record experimental data; Step 7: Analyze the experimental data to obtain the pressure and liquid output data of oil and gas during primary and secondary migration, as well as high-definition photos of the process and distribution characteristics of oil and gas migration and accumulation.

[0005] In a preferred embodiment, in step 2, the preparation process of the solution for the simulation experiment is: preparing a saturated sodium chloride solution as formation water; preparing a calcium chloride solution for standby use; using a red oil-soluble dye to dye kerosene to prepare a red tracer oil phase; using a blue oil-soluble dye to dye kerosene to prepare a blue tracer oil phase.

[0006] In a preferred embodiment, in step 3, quartz sand with a mesh size of 110 mesh and 200 mesh is selected, and sodium carbonate powder is selected and mixed in proportion to obtain conventional formation material, transitional formation material and unconventional formation material; Conventional reservoir materials, 110 mesh quartz sand: 200 mesh quartz sand = 4:1; Transition reservoir material, 110 mesh quartz sand: 200 mesh quartz sand: sodium carbonate powder = 11:7:2; Unconventional reservoir materials: 110 mesh quartz sand: 200 mesh quartz sand: sodium carbonate powder = 11:8:1; The three reservoir materials were loaded into the cavity of the formation sample in layers from bottom to top at a volume ratio of 1:1:1 and subjected to oscillation compaction to simulate the compaction state of the formation under long-term pressure.

[0007] In a preferred embodiment, in step 4, the saturated sodium chloride solution prepared in step 2 is slowly injected into the formation model to fully saturate the formation model. During the injection process, the water absorption of the formation model is closely observed to ensure that the saturated sodium chloride solution is evenly distributed in the pores of the formation model until a stable water flow is discharged from the outlet section without obvious bubbles.

[0008] In a preferred embodiment, step six includes: Start the air compressor and adjust the output pressure. Close valves 2 and 3, open valve 1, and slowly inject the red tracer oil phase from inlet 1 into the formation model using the liquid injection nozzle. Use a high-definition camera to observe and record the migration path and accumulation of the red tracer oil phase in the formation model in real time. Also record the distribution changes and migration speed of the red tracer oil phase. Close valve one, adjust the air compressor pressure, open valve three, and quickly inject the prepared calcium chloride solution from inlet three into the formation model through the liquid injection nozzle to cause a densification reaction between the calcium chloride solution and sodium carbonate. After the injection is completed, close valve three and let the formation model stand to allow the densification reaction to proceed fully. Close valve three, adjust the air compressor pressure, and open valve two. Use the liquid injection nozzle to control the slow injection of blue tracer oil phase from the imported two-dimensional formation model. Use a high-definition camera to observe and record the migration characteristics and accumulation process of the blue tracer oil phase in the densified reservoir in real time, and compare them with the oil and gas migration and accumulation process in conventional reservoirs.

[0009] In a preferred embodiment, in step seven, the collected pressure, liquid output data and high-definition photos are analyzed, including: pressure change curve, relationship between liquid output and time, oil phase distribution characteristics in different reservoirs, and analysis of the control effect of formation porosity and pressure factors on oil and gas migration and accumulation.

[0010] In a preferred embodiment, in step one, the visualization model is fixed on a fixed frame, the angle adjustment frame is connected and placed, the pressure device is connected to ensure that the connection is tight and leak-free, the drainage device is connected to the visualization model through pipe valves, and the high-definition camera is focused on the observation surface of the visualization model.

[0011] The present invention also proposes a simulation device for the full sequence of oil and gas accumulation process of the entire oil and gas system, which is used to implement the above simulation method. The simulation device includes: a fixed frame, a visualization model, an angle adjustment frame, a pressurizing device and a drainage device; The visualization model is placed on a fixed frame, and has a cavity for placing formation samples. An angle adjustment frame is placed below the visualization model to simulate different geological environments or experimental conditions. The pressurizing device is provided at the inlet side of the visualization model and includes an air compressor, a liquid adding tank, a pressure sensor, and pipe valves. The air compressor provides compressed air to simulate the pressure environment of the underground oil and gas reservoir; the liquid adding tank is used to store and add liquid required for the simulation experiment; the pressure sensor is used to detect pressure changes in the pipeline, and the liquid inlet valve is used to control the on-off of liquid or gas; The drainage device comprises a measuring cylinder and a liquid outlet valve, wherein the measuring cylinder is used to measure the volume of liquid flowing out of the visualization model, and the liquid outlet valve is used to drain the liquid.

[0012] Compared with the prior art, the present invention has the following beneficial effects: To address the shortcoming of the single observation surface in traditional two-dimensional physical simulation experiments, the oil and gas filling theme model of the present invention is designed as a translucent visualization device, which can observe the entire process of oil and gas migration and accumulation. In addition, current physical simulations are mostly aimed at oil-water displacement experiments in single strata or fractures. The present invention uses a visualization model to simulate the real "conventional-unconventional" underground strata by controlling the porosity of different strata, more accurately displaying the process of underground oil and gas migration and accumulation, and clarifying the control effect of different parameters such as porosity and permeability on oil and gas accumulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a three-dimensional schematic diagram of the simulation device of the present invention; Figure 2 Schematic diagram of the structure of each part of the simulation device of the present invention.

[0014] Reference numerals 1: Visual model; 2: Angle adjustment frame; 3: Fixed frame; 4: Air compressor; 5: Liquid filling tank; 6: Liquid inlet valve; 7: Pressure sensor; 8: Liquid outlet valve; 9: Measuring cylinder. DETAILED DESCRIPTION

[0015] The present invention is described in detail below with reference to specific examples. The following examples will help those skilled in the art further understand the present invention but are not intended to limit the present invention in any way. It should be noted that variations and modifications are possible within the scope of the present invention, without departing from the spirit of the present invention. These variations and modifications are all within the scope of protection of the present invention.

[0016] Example 1 This embodiment provides a simulation device for the full-sequence oil and gas accumulation process of the entire oil and gas system, including: a fixed frame, a visualization model, an angle adjustment frame, a pressurizing device, and a drainage device.

[0017] The visualization model for oil and gas migration and accumulation simulation is placed on a fixed frame. The visualization model has a cavity for placing formation samples. Three inlets and two outlets are set on both sides of the cavity. Both the inlet and outlet are equipped with filter screens to prevent experimental materials used to simulate the formation from entering the pipeline and causing blockage.

[0018] An angle adjustment rack is placed under the visualization model to simulate different geological environments or experimental conditions.

[0019] The pressurizing device is located at the inlet side of the visualization model for oil and gas migration and accumulation simulation. It consists of an air compressor, a liquid filling tank (or gas cylinder), a pressure sensor, and a liquid inlet valve. The air compressor provides compressed air to move the liquid in the filling tank, or to provide specific air pressure conditions during the experiment to simulate the pressure environment of underground oil and gas reservoirs. The filling tank is used to store and add liquids required for the simulation experiment, such as formation water and simulated oil. The pressure sensor detects pressure changes in the pipeline and provides pressure data for the experiment. The liquid inlet valve controls the on / off flow of liquid or gas, facilitating precise control of fluid flow during the experiment and ensuring experimental readiness and reliability.

[0020] The drainage device includes a measuring cylinder and a liquid outlet valve. The measuring cylinder is used to measure the volume of liquid flowing out of the visualization model, thereby obtaining relevant data such as liquid output during the experiment; the liquid outlet valve is used to drain the liquid.

[0021] Example 2 This embodiment provides a method for simulating the full-sequence oil and gas accumulation process of the entire oil and gas system.

[0022] Step 1: Connect and debug the simulation device in Example 1.

[0023] Fix the visualization model to the fixed frame and connect the angle adjustment bracket.

[0024] Connect the air compressor, liquid filling tank (or gas cylinder), pressure sensor, liquid inlet valve and other pressurizing devices, ensure that the connections between each accessory are tight and leak-free, and correctly connect the drainage device to the main body of the visualization model through pipes and valves.

[0025] Conduct a comprehensive inspection of the entire experimental device, turn on the air compressor to test its pressure output, check the sealing of the liquid filling tank, debug the pressure sensor to ensure accurate display of pressure data, test the opening and closing functions of the pipe valves, and ensure that all equipment can operate normally.

[0026] Place a high-definition camera to focus on the observation surface of the visual model and calibrate the light source to avoid reflections.

[0027] Step 2: Prepare the solution for the simulation experiment.

[0028] Prepare saturated sodium chloride solution as formation water; prepare 1 mol / L calcium chloride solution for standby use; use red oil-soluble dye to dye kerosene to prepare red tracer oil phase; use blue oil-soluble dye to dye kerosene to prepare blue tracer oil phase.

[0029] Step 3: Build a stratum model.

[0030] Grind the sodium carbonate particles into fine powder. Select quartz sand with mesh sizes of 110 mesh and 200 mesh respectively, and then select sodium carbonate powder, and mix them thoroughly according to the proportion to obtain conventional formation materials, transitional formation materials and unconventional formation materials; Conventional reservoir materials, 110 mesh quartz sand: 200 mesh quartz sand = 4:1; Transition reservoir material, 110 mesh quartz sand: 200 mesh quartz sand: sodium carbonate powder = 11:7:2; Unconventional reservoir materials: 110 mesh quartz sand: 200 mesh quartz sand: sodium carbonate powder = 11:8:1.

[0031] Three reservoir materials of varying proportions were loaded into the formation sample cavity in layers from bottom to top at a volume ratio of 1:1:1. The loaded mixture was then compacted by oscillation and topped with an appropriate counterweight to simulate the compaction state of the formation under long-term pressure, making the model more realistic.

[0032] Step 4: Use displacement method to fully saturate the formation model and simulate formation water.

[0033] Slowly inject the saturated sodium chloride solution (formation water) prepared in Step 2 into the visualization model for oil and gas migration and accumulation simulation through the liquid injection nozzle and the liquid inlet valve to fully saturate the formation model in the visualization model. During the injection process, closely observe the water absorption of the formation model to ensure that the saturated sodium chloride solution (formation water) is evenly distributed in the pores of the formation model until a steady flow of water is discharged from the outlet section without obvious bubbles.

[0034] Step 5: Determine the basic physical parameters of the formation model under the saturated formation water state.

[0035] After the formation model is saturated with formation water, close all inlet and outlet valves and record the initial pressure data of the formation model displayed on the pressure display.

[0036] Step 6: Conduct simulation experiments by filling pressure and adding liquid, and record the experimental data.

[0037] Turn on the air compressor and adjust the output pressure to 0.10 MPa. Close valves 2 and 3, and open valve 1. Use the liquid injection nozzle to slowly inject the red tracer oil phase from inlet 1 into the formation model to simulate the preferential migration and accumulation of oil and gas in conventional reservoirs. Use a high-definition camera to observe and record the migration path and accumulation of the red tracer oil phase in the formation model in real time. Also record changes in the red tracer oil phase distribution and migration velocity. Record the following: injection pressure of 0.10 MPa, injection time of 40 minutes, and output of 60 ml from outlet 1.

[0038] Close valve one, adjust the air compressor pressure to 0.60 MPa, and open valve three. Using the liquid dosing device, rapidly inject the prepared 1 mol / L calcium chloride solution from inlet three into the model to induce a densification reaction between the calcium chloride solution and the sodium carbonate. Record the injection pressure as 0.60 MPa, the injection time as 10 minutes, and the total output from outlets one and two as 450 g (solid-liquid mixture). After injection, close valve three and allow the model to rest for 10 minutes to ensure the densification reaction is fully complete.

[0039] Close valve three, adjust the air compressor pressure to 0.60 MPa, and open valve two. Use the liquid injection nozzle to slowly inject the blue tracer oil phase into the inlet two-dimensional formation model. Use a high-definition camera to observe and record the migration and accumulation characteristics of the blue tracer oil phase in the densified reservoir in real time, comparing it with the migration and accumulation of oil and gas in conventional reservoirs. Record: Injection pressure 0.60 MPa, injection time 50 minutes, and output 50 ml from outlet one.

[0040] Step 7: Process the recorded experimental data to obtain high-definition photos of the pressure and liquid output data of oil and gas during primary and secondary migration, as well as the process and distribution characteristics of oil and gas migration and accumulation.

[0041] Collected data such as pressure, fluid output, and high-definition photos are collated and analyzed. This includes, but is not limited to, pressure curves, the relationship between fluid output and time, and the distribution characteristics of oil phases in different reservoirs. This analysis reveals the controlling effects of key factors such as formation porosity and pressure on oil and gas migration and accumulation.

[0042] Finally, the visualization model was dismantled, and sand samples were taken from the conventional, transitional, and unconventional reservoir zones. These sand samples were cleaned and dried, and thin sections of the castings were prepared. Polarizing microscopy was used to observe the pore structure, throat size and distribution, and densification product distribution.

[0043] As shown in Table 1 , the sand body ratio schemes of the simulated formations in different experimental groups simulate rock formations with different porosities; As shown in Table 2, the filling pressure and corresponding liquid output during the experiment of different experimental groups simulate the liquid output under different pressures.

[0044] Table 1 Formation sand body ratio scheme Table 2 Filling pressure, liquid output and oil phase accumulation area The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above. Persons skilled in the art may make various changes or modifications within the scope of the claims without affecting the essence of the present invention. The embodiments of this application and the features within these embodiments may be combined in any manner, unless there is a conflict.

Claims

1. A simulation method for the full sequence of oil and gas accumulation in the entire oil and gas system, characterized by: include: Step 1: Connect and debug the simulation device for the entire oil and gas system and the entire sequence of oil and gas accumulation process; Step 2: preparing a solution for a simulation experiment; Step 3: Build a stratum model; Step 4: Fully saturate the formation model with simulated formation water through displacement method; Step 5: Determine the basic physical parameters of the formation model under the state of saturated formation water; Step 6: Conduct simulation experiments by filling pressure and adding liquid, and record experimental data; Step 7: Analyze the experimental data to obtain the pressure and liquid output data of oil and gas during primary and secondary migration, as well as high-definition photos of the process and distribution characteristics of oil and gas migration and accumulation.

2. The method for simulating the full-sequence oil and gas accumulation process of the entire oil and gas system according to claim 1 is characterized in that: In step 2, the preparation process of the solution for the simulation experiment is as follows: prepare a saturated sodium chloride solution as formation water; prepare a calcium chloride solution for standby use; use a red oil-soluble dye to dye kerosene to prepare a red tracer oil phase; use a blue oil-soluble dye to dye kerosene to prepare a blue tracer oil phase.

3. The method for simulating the full-sequence oil and gas accumulation process of the entire oil and gas system according to claim 1, characterized in that: In step 3, quartz sand with mesh sizes of 110 and 200 is selected, and sodium carbonate powder is selected and mixed in proportion to obtain conventional formation materials, transitional formation materials, and unconventional formation materials; Conventional reservoir materials, 110 mesh quartz sand: 200 mesh quartz sand = 4:1; Transition reservoir material, 110 mesh quartz sand: 200 mesh quartz sand: sodium carbonate powder = 11:7:2; Unconventional reservoir materials: 110 mesh quartz sand: 200 mesh quartz sand: sodium carbonate powder = 11:8:1; The three reservoir materials were loaded into the cavity of the formation sample in layers from bottom to top at a volume ratio of 1:1:1 and subjected to oscillation compaction to simulate the compaction state of the formation under long-term pressure.

4. The method for simulating the full-sequence oil and gas accumulation process of the entire oil and gas system according to claim 2, characterized in that: In step 4, the saturated sodium chloride solution prepared in step 2 is slowly injected into the formation model to fully saturate the formation model. During the injection process, the water absorption of the formation model is closely observed to ensure that the saturated sodium chloride solution is evenly distributed in the pores of the formation model until a stable water flow is discharged from the outlet section without obvious bubbles.

5. The method for simulating the full-sequence oil and gas accumulation process of the entire oil and gas system according to claim 1 is characterized in that: Step six includes: Start the air compressor and adjust the output pressure. Close valves 2 and 3, open valve 1, and slowly inject the red tracer oil phase from inlet 1 into the formation model using the liquid injection nozzle. Use a high-definition camera to observe and record the migration path and accumulation of the red tracer oil phase in the formation model in real time. Also record the distribution changes and migration speed of the red tracer oil phase. Close valve one, adjust the air compressor pressure, open valve three, and quickly inject the prepared calcium chloride solution from inlet three into the formation model through the liquid injection nozzle to cause a densification reaction between the calcium chloride solution and sodium carbonate. After the injection is completed, close valve three and let the formation model stand to allow the densification reaction to proceed fully. Close valve three, adjust the air compressor pressure, and open valve two. Use the liquid injection nozzle to control the slow injection of blue tracer oil phase from the imported two-dimensional formation model. Use a high-definition camera to observe and record the migration characteristics and accumulation process of the blue tracer oil phase in the densified reservoir in real time, and compare them with the oil and gas migration and accumulation process in conventional reservoirs.

6. The method for simulating the full-sequence oil and gas accumulation process of the entire oil and gas system according to claim 1, characterized in that: In step seven, the collected pressure and liquid output data and high-definition photos are analyzed, including: pressure change curves, the relationship between liquid output and time, and the distribution characteristics of oil phases in different reservoirs, and the control of formation porosity and pressure factors on oil and gas migration and accumulation.

7. The method for simulating the full-sequence oil and gas accumulation process of the entire oil and gas system according to claim 1, characterized in that: In step one, the visualization model is fixed on a fixed frame, connected to an angle adjustment frame, connected to a pressurizing device to ensure a tight connection without leakage, the drainage device is connected to the visualization model through pipe valves, and the high-definition camera is focused on the observation surface of the visualization model.

8. A simulation device for the full sequence of oil and gas accumulation in the entire oil and gas system, characterized by: Used to implement the simulation method according to any one of claims 1 to 7, the simulation device comprises: a fixed frame, a visualization model, an angle adjustment frame, a pressurizing device and a drainage device; The visualization model is placed on a fixed frame, and has a cavity for placing formation samples. An angle adjustment frame is placed below the visualization model to simulate different geological environments or experimental conditions. The pressurizing device is provided at the inlet side of the visualization model and includes an air compressor, a liquid adding tank, a pressure sensor, and pipe valves. The air compressor provides compressed air to simulate the pressure environment of the underground oil and gas reservoir; the liquid adding tank is used to store and add liquid required for the simulation experiment; the pressure sensor is used to detect pressure changes in the pipeline, and the liquid inlet valve is used to control the on-off of liquid or gas; The drainage device comprises a measuring cylinder and a liquid outlet valve, wherein the measuring cylinder is used to measure the volume of liquid flowing out of the visualization model, and the liquid outlet valve is used to drain the liquid.

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