Functional probe for measuring rock-liquid adhesive force and manufacturing method thereof

Abstract

The invention provides a functional probe for measuring rock-liquid adhesive force and a manufacturing method thereof, the probe is an atomic force microscope probe, and rock sample particles are adsorbed at the detection end of the probe. The manufacturing method comprises the following steps: cleaning the detection end of the probe, moving the probe to a position above the rock sample particles, and adsorbing the rock sample particles by the detection end of the probe to obtain the functional probe. According to the functional probe and the manufacturing method, the interaction force relation between rock and liquid can be rapidly and accurately represented, and the manufacturing method is simple and convenient.

Description

Technical Field

[0001] The invention belongs to the field of shale research and relates to a functional probe for measuring rock-liquid adhesion and a manufacturing method thereof. Background Art

[0002] Shale is a natural multi-scale heterogeneous composite material composed of mineral particles, clay mineral aggregates and organic matter. Due to the bottom porosity and low permeability of shale itself, it is necessary to use related measures such as fracturing to achieve oil and gas production increase. However, the selection of fracturing parameters depends largely on the mechanical properties of shale. Traditional uniaxial and triaxial compression experiments, acoustic logging, seismic attribute extraction and inversion and other related technologies have been widely used to evaluate the mechanical properties of shale, but these methods cannot achieve the study of the mechanical properties of shale at the nanoscale. In the past 20 years, with the exploration and development of unconventional resources such as shale gas, the application of nanoindentation technology has gradually expanded to the field of rock materials, and the test objects have also expanded from homogeneous bodies to heterogeneous bodies, gradually focusing on the study of rock deformation and fracture, and has been widely used to measure the microscopic mechanical properties of shale. However, the testing method of nanoindentation technology is to achieve the testing purpose by applying a load to the test object to cause it to be damaged, and the test range is limited to discrete points within a certain area, and the mechanical properties represented are only at the micron level rather than the true nanometer level. Moreover, the result of the nanoindentation test is only a load-displacement curve. The mechanical parameters derived and calculated by it are currently mostly limited to elastic modulus and hardness, which cannot fully reflect the mechanical properties of the test object, and cannot complete the characterization of the interaction force between rock and liquid.

[0003] Since the 1980s, with the increasing demand for technology in the exploration, development and research of unconventional shale oil and gas reservoirs, atomic force microscopy (AFM) has gradually opened up a new field of microscopic research in the oil and gas field, becoming the best choice for studying nanoscale pore structures, organic matter such as kerogen, minerals and microcracks in shale. Compared with nanoindentation technology, AFM can not only perform high-precision and targeted tests on individual components, but also the deformation and damage of the probe during the test are very small. Summary of the invention

[0004] In order to solve the technical problems existing in the prior art, the present invention provides a functional probe for measuring rock-liquid adhesion and a method for making the same. The functional probe and the method for making the same can quickly and accurately characterize the interaction force relationship between rock and liquid, and the method for making the same is simple.

[0005] In order to achieve the above technical effects, the present invention adopts the following technical solutions:

[0006] One of the purposes of the present invention is to provide a functional probe for measuring rock-liquid adhesion, wherein the probe is an atomic force microscope probe, and rock sample particles are adsorbed on the detection end of the probe.

[0007] As a preferred technical solution of the present invention, the particle size of the rock sample particles is nanometer or submicron.

[0008] In the present invention, the advantage of the functional probe provided is that there is no need to consider the wettability of the probe itself, and the conventional probe and the functional probe only need to be replaced once. Compared with the liquid-type functional probe, there is no need to frequently replace the conventional probe and the functional probe to achieve the measurement of the adhesion force between rocks and different fluids, which simplifies the experimental operation process. The probe can be used to measure the adhesion force between rocks and different liquid materials.

[0009] The second object of the present invention is to provide a method for making a functional probe for measuring rock-liquid adhesion provided by the first object, the method comprising:

[0010] The detection end of the probe is cleaned, and the probe is moved above the rock sample particles. The detection end of the probe adsorbs the rock sample particles to obtain the functional probe.

[0011] As a preferred technical solution of the present invention, a polar solvent is used to clean the detection end of the probe.

[0012] As a preferred technical solution of the present invention, an adhesive is applied to the detection end of the cleaned probe.

[0013] As a preferred technical solution of the present invention, the method of applying the adhesive includes: observing through the optical microscope system of the atomic force microscope, adjusting the position of the probe to move it above the adhesive, continuing to adjust the height of the probe to make it close to the adhesive surface until it contacts the adhesive surface at a position between the detection end and the cantilever beam, maintaining the stationary state, and lifting the probe.

[0014] As a preferred technical solution of the present invention, the rock sample particles are placed on a slide.

[0015] A third object of the present invention is to provide a method for measuring rock-liquid adhesion, the method comprising:

[0016] Place the liquid sample on the sample stage, perform a first scan using the original probe and record the original scan position;

[0017] The functional probe provided by one of the purposes is used to scan the original scanning position, and the interaction force curve between the rock sample and the liquid sample is measured.

[0018] As a preferred technical solution of the present invention, before the second scan, an optical microscope of an atomic force microscope is used to find the original scan area.

[0019] As a preferred technical solution of the present invention, the interaction force curve between the rock sample and the liquid sample is subjected to mathematical analysis to obtain the relationship between the interaction force between the rock and the liquid and the distance.

[0020] As a preferred technical solution of the present invention, the method for measuring rock-liquid adhesion includes:

[0021] Placing a liquid sample on a sample stage, scanning the liquid sample using a functional probe provided in one of the purposes, and determining an interaction force curve between the rock sample and the liquid sample;

[0022] The interaction force curve between the rock sample and the liquid sample is mathematically analyzed to obtain the relationship between the interaction force between the rock and the liquid and the distance.

[0023] Compared with the prior art, the present invention has at least the following beneficial effects:

[0024] (1) The present invention provides a functional probe for measuring rock-liquid adhesion and a method for making the same. The functional probe can quickly and accurately characterize the interaction force relationship between rock and liquid, overcoming the limitations of existing rock research methods;

[0025] (2) The present invention provides a functional probe for measuring rock-liquid adhesion and a method for making the same. The method for making the same is simple and low-cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the structure of the functional probe provided in a specific embodiment of the present invention;

[0027] Figure 2 A physical diagram of a functional probe provided in a specific embodiment of the present invention;

[0028] Figure 3 This is a curve showing the change of the interaction force between the rock sample and the liquid sample with the distance in the embodiment of the present invention.

[0029] The present invention is further described in detail below. However, the following examples are only simplified examples of the present invention and do not represent or limit the scope of protection of the present invention. The scope of protection of the present invention shall be subject to the claims. DETAILED DESCRIPTION

[0030] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0031] A specific embodiment of the present invention provides a functional probe for measuring rock-liquid adhesion, wherein the probe is an atomic force microscope probe, and rock sample particles are adsorbed on the detection end of the probe.

[0032] In a specific embodiment of the present invention, rock sample particles can be refined by ball milling or other refinement methods to obtain nano-scale or submicron-scale rock sample particles.

[0033] In a specific embodiment of the present invention, the specifications of the atomic force microscope probe can be specifically selected according to the needs of the test and are not specifically limited here.

[0034] A specific embodiment of the present invention provides a method for making a functional probe for measuring rock-liquid adhesion, the method comprising:

[0035] The detection end of the probe is cleaned, and the probe is moved above the rock sample particles. The detection end of the probe adsorbs the rock sample particles to obtain the functional probe.

[0036] In a specific embodiment of the present invention, the polar solvent used to clean the detection end of the probe is preferably an alcohol solvent, and more preferably an ethanol solution.

[0037] In a specific embodiment of the present invention, the binder may be a commonly used binder that has good adhesion to rock samples, and is not specifically limited herein.

[0038] In a specific embodiment of the present invention, the adhesive is placed on the surface of the slide, and the slide is preferably a mica sheet.

[0039] In a specific embodiment of the present invention, the slide for placing the rock sample particles is preferably a mica slide.

[0040] A specific embodiment of the present invention provides a method for measuring rock-liquid adhesion, the method comprising:

[0041] The liquid sample is placed on a sample stage, the liquid sample is scanned using a functional probe, and an interaction force curve between the rock sample and the liquid sample is measured.

[0042] In one embodiment of the present invention, the method for preparing the liquid sample can be to drop the liquid to be tested onto a glass slide and allow it to air-dry to form a thin film.

[0043] In one embodiment of the present invention, the surface of the liquid sample is maintained in a horizontal plane.

[0044] In a specific embodiment of the present invention, the interaction force curve between the rock sample and the liquid sample can be analyzed by analysis software. The specific analysis software is commonly used in the field and is not specifically limited here.

[0045] To better illustrate the present invention and facilitate understanding of the technical solution of the present invention, typical but non-limiting embodiments of the present invention are as follows:

[0046] Example 1

[0047] This embodiment provides a method for measuring rock-liquid adhesion, the method comprising:

[0048] Instrument: Oxford Instruments Jupiter XR atomic force microscope was used.

[0049] Selection and preparation of shale samples: Select samples from the shale formations in the Changqing area, use a rock sample particle crusher to make crushed samples, and screen out crushed samples smaller than 1 mm, and then use a ball mill to further make spherical samples with a diameter of ≤1μm; spread the prepared spherical samples on a glass slide, ensuring that there is a distance of about 1mm between the crushed samples to facilitate the probe to stick to them.

[0050] Probe type: Choose PN-TR-TL probe or ContAI-G contact probe. Drop 502 glue on the glass slide with a thickness of not less than 1mm. Observe with the atomic force microscope, adjust the probe position to move it above the glue on the glass slide, and continue to adjust the probe height to make it close to the glue surface until the position between the needle tip and the cantilever beam contacts the glue surface. Stay for 10 seconds and lift the probe to obtain a probe with adhesive ability.

[0051] Functional probe preparation: Use the atomic force microscope's built-in optical microscope system to find rock fragments with relatively regular shapes and sizes. You can choose organic fragments, pyrite fragments, or felsic fragments as needed, adjust the probe's proximity position with adhesive ability, and stick the selected rock fragments to make a functional probe ( Figure 1 , Figure 2 ).

[0052] Adhesion force measurement: Place the liquid to be tested on a glass slide. The liquid to be tested can be crude oil, formation water, polymer solution, fracturing fluid, surfactant, or other liquids related to the oil and gas industry in the target block. Select the contact mode of the force microscope, and obtain the force-distance curve between the organic matter fragments and the crude oil through the process of the functional probe contacting the liquid on the glass slide and lifting it up ( Figure 3 ), the adhesion value between solid and liquid can be obtained according to the graphical method.

[0053] placing a liquid sample on a sample stage, scanning the liquid sample using a functional probe, and determining an interaction force curve between the rock sample and the liquid sample;

[0054] The interaction force curve between the rock sample and the liquid sample is mathematically analyzed to obtain the relationship between the interaction force between the rock and the liquid and the distance.

[0055] The applicant declares that the present invention illustrates the detailed structural features of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned detailed structural features, that is, it does not mean that the present invention must rely on the above-mentioned detailed structural features to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the components selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0056] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0057] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0058] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A functional probe for measuring rock-liquid adhesion, characterized in that: The probe is an atomic force microscope probe, and the detection end of the probe is adsorbed with rock sample particles.

2. The functional probe according to claim 1, characterized in that The particle size of the rock sample particles is nanometer or submicron.

3. A method for making a functional probe for measuring rock-liquid adhesion according to claim 1 or 2, characterized in that: The production method comprises: The detection end of the probe is cleaned, and the probe is moved above the rock sample particles. The detection end of the probe adsorbs the rock sample particles to obtain the functional probe.

4. The method according to claim 3, characterized in that: The detection end of the probe is cleaned using a polar solvent.

5. The manufacturing method according to claim 3, characterized in that: Apply adhesive to the detection end of the cleaned probe.

6. The method according to claim 4, characterized in that: The method for applying the adhesive comprises: observing through the optical microscope system of the atomic force microscope, adjusting the position of the probe to move it above the adhesive, continuing to adjust the height of the probe to make it close to the adhesive surface until it contacts the adhesive surface at a position between the detection end and the cantilever beam, maintaining the stationary state, and lifting the probe.

7. The manufacturing method according to claim 3, characterized in that: The rock sample particles are placed on a slide.

8. A method for measuring rock-liquid adhesion, characterized in that: The method comprises: A liquid sample is placed on a sample stage, the liquid sample is scanned using the functional probe provided in claim 1 or 2, and an interaction force curve between the rock sample and the liquid sample is measured.

9. The method according to claim 8, characterized in that The interaction force curve between the rock sample and the liquid sample is mathematically analyzed to obtain the relationship between the interaction force between the rock and the liquid and the distance.

10. The method according to claim 8 or 9, characterized in that: The method comprises: Placing a liquid sample on a sample stage, scanning the liquid sample using the functional probe provided in claim 1 or 2, and measuring an interaction force curve between the rock sample and the liquid sample; The interaction force curve between the rock sample and the liquid sample is mathematically analyzed to obtain the relationship between the interaction force between the rock and the liquid and the distance.

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