Rock core pore basic parameter acquisition device

Abstract

The utility model discloses a device for acquiring basic parameters of core pores. The device comprises a porosity measurement module, a saturation measurement module and a core clamping module, the porosity measuring module comprises a liquid inlet assembly and a liquid metering assembly; the liquid inlet assembly is communicated with a liquid inlet pipeline of the rock core clamping module; the liquid metering assembly is communicated with a liquid outlet pipeline of the rock core clamping module; the saturation measuring module comprises a gas inlet assembly and a gas metering assembly; the air inlet assembly is communicated with an air inlet pipeline of the rock core clamping module; and the gas metering assembly is communicated with a liquid outlet pipeline of the rock core clamping module. By arranging the porosity measurement module, the saturation measurement module and the core clamping module, the porosity and the saturation of the core can be measured. The pressure stabilizing tank is arranged at the outlet of the core holder, and the back pressure valve is arranged at the top of the pressure stabilizing tank, so that the problem of unstable pressure in the core holder caused by direct connection of the core holder and the back pressure valve is solved.

Description

Technical Field

[0001] The present application relates to the field of core detection technology, and in particular to a device for acquiring basic parameters of core pores. Background Art

[0002] The basic parameters of core pores mainly include porosity and saturation, which are crucial parameters in rock physical property analysis and are of great significance to oil and gas exploration and development. Core porosity refers to the volume ratio of pores in rocks, which is a key parameter for evaluating the ability of rocks to store fluids. Generally speaking, the higher the porosity, the stronger the ability of rocks to store fluids, which has positive significance for exploration and development. Saturation describes the degree to which pores are filled with fluids, reflecting the existence state of fluids such as oil, gas, and water in rocks. Correctly evaluating the saturation of rocks is crucial to determining the type of fluids and reserve distribution in rocks.

[0003] By jointly studying the porosity and saturation of cores, we can have a more comprehensive understanding of the reservoir characteristics of underground rocks, evaluate the potential and risks of oil and gas exploration, and guide the design of drilling and production processes. At the same time, in-depth research on the pore structure and pore connectivity in cores will help improve the understanding and prediction of reservoir fluids in underground rocks, and provide more accurate guidance and support for oil and gas exploration and development.

[0004] Therefore, the study of core porosity and saturation has important theoretical and practical value in the fields of geological exploration and oil and gas development.

[0005] Traditional core porosity measurement devices cannot measure both porosity and saturation parameters at the same time, and require replacement of device components, which increases operational difficulty and complexity and reduces detection efficiency.

[0006] The conventional method for porosity measurement generally uses a Hassler clamp to measure the pore volume of the rock by applying pore pressure, and then obtains the porosity based on the total volume of the rock sample (for example, Han Xuehui, Zhang Hao, Mao Xinjun, etc. A method for measuring helium porosity in tight reservoirs based on core chamber stress-strain and uncertainty analysis [J]. Chinese Journal of Geophysics, 2021, 64(01): 289-297.).

[0007] A back pressure valve is generally provided at the outlet of the Hasler clamp. The back pressure valve is directly connected to the outlet of the Hasler clamp, which will cause unstable pressure in the Hasler clamp and make it difficult to establish the actual formation pressure of the reservoir.

[0008] Secondly, the back pressure valve is easy to deform, and the volume of the manifold from the core outlet to the back pressure valve is difficult to accurately measure. It is impossible to accurately measure the volume of liquid entering the core pore volume when the pore pressure increases, which affects the measurement accuracy of the pore volume. (For example, Lu Feng, Wang Jian, Pan Xiaohui, etc. An experimental measurement method for the porosity of abnormally high-pressure deep oil and gas reservoirs with dual pump joint control and joint measurement [J / OL]. Progress in Geophysics: 1-8 [2024-03-25].)

[0009] In traditional porosity measurement devices, when the first drop of liquid appears at the outlet of the back pressure valve, it is considered that all the gas in the device is discharged. However, in the actual measurement process, invisible gas may be discharged first before the first drop of liquid is discharged, and then liquid is discharged, or gas and liquid are discharged alternately. There is still a small amount of gas in the device, which leads to greater measurement errors.

[0010] Some traditional porosity measurement devices use flow meters to measure the amount of fluid injected. Since the fluid injection time is short, existing flow meters cannot accurately measure such fluids, which will increase the measurement error of the flow meter.

[0011] The information disclosed in the background technology section is only intended to increase the understanding of the overall background of the utility model, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to ordinary technicians in the field. Utility Model Content

[0012] In order to solve the above-mentioned technical problems, the present application provides a device for acquiring basic parameters of core pores, which can realize simultaneous measurement of core saturation and porosity, thereby improving the accuracy of measurement results.

[0013] The present application provides a core pore basic parameter acquisition device, including: a porosity measurement module, a saturation measurement module, and a core clamping module;

[0014] The porosity measurement module includes: a liquid inlet component and a liquid metering component; the liquid inlet component is connected to the liquid inlet pipeline of the core clamping module; the liquid metering component is connected to the liquid outlet pipeline of the core clamping module;

[0015] The saturation measurement module comprises: an air intake component and a gas metering component; the air intake component is connected with the air intake pipeline of the core clamping module; the gas metering component is connected with the liquid outlet pipeline of the core clamping module.

[0016] Preferably, the liquid inlet assembly comprises: a water bucket, a manual pump, and a piston cylinder; the water bucket is connected to the liquid inlet pipeline of the manual pump; the liquid outlet of the manual pump is connected to the bottom pipeline of the piston cylinder;

[0017] The core clamping module comprises: a core clamp; the top of the piston cylinder is connected to the liquid inlet pipeline of the core clamp;

[0018] Preferably, the liquid inlet assembly includes: a first ball valve, a second ball valve, and a first pressure gauge; the first ball valve is arranged on the pipeline connecting the water bucket and the manual pump; the second ball valve is arranged on the pipeline connecting the manual pump and the piston cylinder.

[0019] Preferably, the liquid inlet assembly comprises: a liquid discharge pipe and a drain valve; the liquid discharge pipe is connected to the pipeline at the bottom of the piston cylinder; and the drain valve is arranged on the liquid discharge pipe.

[0020] Preferably, the liquid metering assembly includes: a pressure stabilizing tank, a measuring cylinder, and a second pressure gauge; the pressure stabilizing tank is connected to the liquid outlet pipeline of the core clamp; the liquid outlet of the pressure stabilizing tank is set deep into the bottom of the measuring cylinder through the pipeline; the second pressure gauge is set on the pressure stabilizing tank.

[0021] Preferably, the air intake assembly includes: a gas cylinder, a heater, and a first thermometer; the gas outlet of the gas cylinder is connected to the air inlet pipeline of the heater; the gas outlet of the heater is connected to the air inlet pipeline of the core clamp; and a first thermometer is arranged on the pipeline connecting the air inlets of the heater and the core clamp.

[0022] Preferably, the air inlet assembly comprises: a sixth ball valve; and a sixth ball valve is arranged on the pipeline connecting the air inlets of the heater and the core clamp.

[0023] Preferably, the gas metering assembly includes: a condenser, a second thermometer, and a condensate recovery bucket; the air inlet of the condenser is connected to the air outlet pipeline of the core holder; the air outlet of the condenser is connected to the condensate recovery bucket pipeline, and a second thermometer is arranged on the connected pipelines.

[0024] Preferably, the core clamping module comprises: an oil bath; a core clamp clamping the core sample to be tested; and the core clamp is arranged in the oil bath.

[0025] The beneficial effects of this application include:

[0026] 1) The core pore basic parameter acquisition device provided in this application can measure the porosity and saturation of the core by setting a porosity measurement module, a saturation measurement module and a core clamping module. A pressure stabilizing tank is set at the outlet of the core clamp, and a back pressure valve is set on the top of the pressure stabilizing tank to solve the problem of unstable pressure in the core clamp caused by the core clamp being directly connected to the back pressure valve.

[0027] 2) The core pore basic parameter acquisition device provided in the present application can accurately measure the fluid volume in the piston cylinder, core clamp, pressure-stabilizing tank, measuring cylinder and pipeline, solving the problem that the volume of the manifold from the core outlet to the back pressure valve is difficult to measure.

[0028] 3) The core pore basic parameter acquisition device provided in this application adopts a manual pump pressurization and a piston cylinder to measure the fluid injection amount to solve the problem of large flow meter measurement error and achieve accurate measurement of fluid volume.

[0029] 4) The core pore basic parameter acquisition device provided by the present application has a back pressure valve on the top of the pressure regulating tank, and the gas accumulates in the upper space of the pressure regulating tank. The structure can use the continuous outflow of liquid in the back pressure valve as a sign of complete gas discharge, thereby reducing the measurement error caused by the alternating discharge of gas and liquid. The volume of the outflowing liquid can be accurately measured by a measuring cylinder connected to the pressure regulating tank pipeline, and the structure can be used without affecting the measurement of the total volume of the liquid. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A schematic diagram of a device for acquiring basic parameters of core pores in at least one embodiment provided in the present application;

[0031] Legend:

[0032] Bucket 1, first ball valve 2, manual pump 3, second ball valve 4, drain valve 5, piston cylinder 6, first pressure gauge 7, third ball valve 8, fourth ball valve 12, pressure regulating tank 13, second pressure gauge 14, back pressure valve 15, measuring cylinder 16, gas cylinder 17, fifth ball valve 18, heater 19, first thermometer 20, sixth ball valve 21, seventh ball valve 22, condenser 23, second thermometer 24, condensate recovery bucket 25, oil bath 9, core holder 10, core sample to be tested 11. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0035] The controller used in this embodiment is an existing structure, and the control circuit can be implemented through simple programming by technicians in this field. It belongs to the common knowledge in this field. It is only used without modification, so the control method and circuit connection are not described in detail.

[0036] The technical means that are not described in detail in this application and are not used to solve the technical problems of this application are all set according to the common knowledge in the field, and can be implemented in a variety of common knowledge settings.

[0037] See also Figure 1 The core pore basic parameter acquisition device provided in the present application includes: a porosity measurement module, a saturation measurement module and a core clamping module.

[0038] The porosity measurement module includes: a water bucket 1, a first ball valve 2, a manual pump 3, a second ball valve 4, a drain valve 5, a piston cylinder 6, a first pressure gauge 7, a third ball valve 8, a fourth ball valve 12, a pressure-stabilizing tank 13, a second pressure gauge 14, a back pressure valve 15, and a measuring cylinder 16;

[0039] The saturation measurement module includes a gas cylinder 17, a fifth ball valve 18, a heater 19, a first thermometer 20, a sixth ball valve 21, a seventh ball valve 22, a condenser 23, a second thermometer 24, and a condensate recovery bucket 25;

[0040] The core clamping module comprises an oil bath 9, a core clamp 10, and a core sample 11.

[0041] The inlet of the manual pump 3 is connected to the pipeline of the water bucket 1 through the first ball valve 2, and the outlet of the manual pump 3 is connected to the pipeline at the bottom of the piston cylinder 6 through the second ball valve 4. The drain valve 5 is connected to the pipeline at the bottom of the piston cylinder 6 to discharge the water in the lower space of the piston cylinder 6.

[0042] The first pressure gauge 7 is connected to the top pipeline of the piston cylinder 6 and is used to measure the pressure in the upper space of the piston cylinder 6 .

[0043] The piston cylinder 6 is connected to the liquid inlet of the core holder 10 through the third ball valve 8. The core holder 10 used in this application can be a Hasler holder. The structure of the core holder 10 does not belong to the improvement object of the utility model. The existing commercially available core holder 10 can be used.

[0044] The core sample 11 to be tested is placed in the core holder 10. The core holder 10 is placed in the oil bath 9, and the temperature in the core holder 10 is effectively controlled by adjusting the temperature of the oil bath 9. The outlet of the core holder 10 is connected to the inlet pipeline of the fourth ball valve 12. The fourth ball valve 12 extends into the bottom of the pressure-stabilizing tank 13 through a pipeline. The second pressure gauge 14 is connected to the top pipeline of the pressure-stabilizing tank 13, and can display the pressure in the pressure-stabilizing tank 13. One end of the back pressure valve 15 is connected to the top pipeline of the pressure-stabilizing tank 13, and the other end extends into the bottom of the measuring cylinder 16 through a pipeline.

[0045] The gas cylinder 17 is connected to the gas inlet pipeline of the heater 19 through the fifth ball valve 18, and the heater 19 can heat the gas to a high temperature state. The first thermometer 20 is set on the outlet pipe of the heater 19, which can display the temperature of the heated gas. The gas outlet of the heater 19 is connected to the gas inlet pipeline of the core holder 10, and the sixth ball valve 21 is connected to the connecting pipeline. The condenser 23 is connected to the gas outlet pipeline of the core holder 10 through the seventh ball valve 22.

[0046] The condenser 23 is placed vertically, and the gas outlet pipe of the condenser 23 extends into the interior of the condensation recovery barrel 25. The second thermometer 24 is arranged on the pipe of the gas outlet of the condenser 23 to display the temperature of the gas after condensation.

[0047] Volume measurement of the system except the iron block and the piston cylinder 6: Take an iron block with the same shape and volume as the core sample 11 and place it in the core holder 10. Clear the water in the device, fill the upper space of the piston cylinder 6 with water, the volume of water is recorded as V1, and the piston inside the piston cylinder 6 is placed at the bottom of the piston cylinder 6. Adjust the pressure set by the back pressure valve 15, use the manual pump 3 to pump the water in the bucket 1 into the lower space of the piston cylinder 6, the piston moves upward to push the water in the upper space of the piston cylinder 6 into the core holder 10 and the pressure tank 13, and the water in the pressure tank 13 is discharged into the measuring cylinder 16 through the back pressure valve 15.

[0048] After the water flow discharged by the back pressure valve 15 is continuous and stable, the manual pump 3 is stopped, and the volume of water in the measuring cylinder 16 is recorded as V2, and the data of the first pressure gauge 7 is recorded as P1.

[0049] Close the second ball valve 4, open the drain valve 5, and measure the volume of water discharged by the drain valve 5 to be V3.

[0050] V3-V2=V4, V4 is the volume of the system excluding the iron block and the piston cylinder 6.

[0051] Determination of the oil and water volume of the core: The core sample 11 containing oil and water is placed in the core holder 10. Close all valves, start the oil bath 9, heater 19, condenser 23, and after the temperature stabilizes, open the fifth ball valve 18, the sixth ball valve 21, the seventh ball valve 22 and the gas cylinder 17. The oil bath 9 heats the temperature of the core sample 11 to a high temperature state, and the oil and water inside the core sample 11 are heated to a steam state.

[0052] The fifth ball valve 18 controls the gas flow rate of the gas cylinder 17. The gas is heated to a high temperature in the heater 19. The high-temperature gas enters the gap of the core sample 11 to be tested. The high-temperature gas carries the water vapor and oil vapor in the core sample 11 to the condenser 23. The condenser 23 liquefies the water vapor and oil vapor to form droplets that enter the condensation recovery bucket 25.

[0053] The gas cylinder 17 continues to discharge gas to the outlet pipe of the condenser 23 for 4 hours. If no liquid condenses and flows out, it is considered that the oil and water in the core sample 11 have all flowed out.

[0054] The water volume V5 and the oil volume V6 in the condensate recovery tank 25 are measured.

[0055] After the core oil and water volume determination is completed, the core sample 11 to be tested is placed in the core holder 10. The water in the device is cleared, and the upper space of the piston cylinder 6 is filled with water until the piston inside the piston cylinder 6 is placed at the bottom of the piston cylinder 6. The volume of water added is recorded as V7.

[0056] The pressure set by the back pressure valve 15 is adjusted according to the data P1 of the first pressure gauge 7, and the water in the water bucket 1 is pumped into the lower space of the piston cylinder 6 by the manual pump 3. The piston moves upward to push the water in the upper space of the piston cylinder 6 into the core clamp 10 and the pressure stabilizing tank 13, and the water in the pressure stabilizing tank 13 is discharged into the measuring cylinder 16 through the back pressure valve 15.

[0057] After the water flow discharged by the back pressure valve 15 is continuous and stable, the manual pump 3 is stopped and the volume of water in the measuring cylinder 16 is recorded as V8.

[0058] Close the second ball valve 4, open the drain valve 5, and measure the volume of water discharged by the drain valve 5 to be V9.

[0059] The difference between V9 and V8 is the volume V10 of the system excluding the core and the piston cylinder.

[0060] The volume difference between V10 and V4 is the pore volume V11 in the core.

[0061] The core is a rectangular parallelepiped. Use a ruler to measure the length, width and height of the core and calculate the volume V12 of the core.

[0062] The ratio of the pore volume V11 to the core volume V12 is the porosity.

[0063] The water saturation of the core is the ratio of the water volume V5 to the pore volume V11.

[0064] The oil saturation of the core is the ratio of the oil volume V6 to the pore volume V11.

[0065] Although all the above embodiments use Figure 1 However, as a person skilled in the art can clearly know, there is no need to provide a separate drawing to represent, as long as the missing parts or structural features in the embodiment are removed from the drawing. This is clear to those skilled in the art. Of course, the embodiment with more parts is only the optimal embodiment, and the embodiment with fewer parts is the basic embodiment, but it can also achieve the basic purpose of the utility model, so all these modified embodiments are within the protection scope of the utility model.

[0066] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for obtaining basic parameters of core pores, characterized in that: include: Porosity measurement module, saturation measurement module, core clamping module; The porosity measurement module includes: a liquid inlet component and a liquid metering component; the liquid inlet component is connected to the liquid inlet pipeline of the core clamping module; the liquid metering component is connected to the liquid outlet pipeline of the core clamping module; The saturation measurement module comprises: an air intake component and a gas metering component; the air intake component is connected with the air intake pipeline of the core clamping module; the gas metering component is connected with the liquid outlet pipeline of the core clamping module.

2. The core pore basic parameter acquisition device according to claim 1, characterized in that: The liquid inlet assembly comprises: a water bucket (1), a manual pump (3), and a piston cylinder (6); the water bucket (1) is connected to the liquid inlet pipeline of the manual pump (3); the liquid outlet of the manual pump (3) is connected to the bottom pipeline of the piston cylinder (6); The core clamping module comprises: a core clamping device (10); the top of the piston cylinder (6) is connected to the liquid inlet pipeline of the core clamping device (10).

3. The core pore basic parameter acquisition device according to claim 2, characterized in that: The liquid inlet assembly comprises: a first ball valve (2), a second ball valve (4), and a first pressure gauge (7); the first ball valve (2) is arranged on a pipeline connecting the water bucket (1) and the manual pump (3); and the second ball valve (4) is arranged on a pipeline connecting the manual pump (3) and the piston cylinder (6).

4. The core pore basic parameter acquisition device according to claim 2, characterized in that: The liquid inlet assembly comprises: a liquid discharge pipe and a water discharge valve (5); the liquid discharge pipe is connected to a pipeline at the bottom of the piston cylinder (6); and the water discharge valve (5) is arranged on the liquid discharge pipe.

5. The core pore basic parameter acquisition device according to claim 2, characterized in that: The liquid metering assembly comprises: a pressure stabilizing tank (13), a measuring cylinder (16), and a second pressure gauge (14); the pressure stabilizing tank (13) is connected to a liquid outlet pipeline of a core holder (10); the liquid outlet of the pressure stabilizing tank (13) is arranged deep into the bottom of the measuring cylinder (16) through the pipeline; and the second pressure gauge (14) is arranged on the pressure stabilizing tank (13).

6. The core pore basic parameter acquisition device according to claim 2, characterized in that: The air intake assembly comprises: a gas cylinder (17), a heater (19), and a first thermometer (20); the gas outlet of the gas cylinder (17) is connected to the gas inlet pipeline of the heater (19); the gas outlet of the heater (19) is connected to the gas inlet pipeline of the core holder (10); and the first thermometer (20) is arranged on the pipeline connecting the gas inlets of the heater (19) and the core holder (10).

7. The core pore basic parameter acquisition device according to claim 6, characterized in that: The air intake assembly comprises: a sixth ball valve (21); the sixth ball valve (21) is arranged on a pipeline connecting the air intakes of the heater (19) and the core clamp (10).

8. The core pore basic parameter acquisition device according to claim 2, characterized in that: The gas metering component comprises: a condenser (23), a second thermometer (24), and a condensate recovery bucket (25); the gas inlet of the condenser (23) is connected to the gas outlet pipeline of the core holder (10); the gas outlet of the condenser (23) is connected to the condensate recovery bucket (25) pipeline, and the second thermometer (24) is arranged on the connected pipeline.

9. The core pore basic parameter acquisition device according to claim 2, characterized in that: The core clamping module comprises: an oil bath (9); a core clamping device (10) clamping a core sample to be tested (11); and the core clamping device (10) being arranged in the oil bath (9).

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