A sample preparation device and method suitable for vitrinite reflectance determination by image method

Abstract

The application discloses a sample preparation device and method suitable for determining vitrinite reflectivity by an image method, and the device comprises a sample table, the top of the sample table is provided with a sample groove, and the sample groove is used for carrying a sample to be measured; a plurality of standard sample grooves are uniformly arranged in the sample groove; and a plurality of standard sample tubes are inserted into the standard sample grooves, and the standard sample tubes are used for containing standard samples. The sample preparation device suitable for determining vitrinite reflectivity by the image method inserts the standard sample tubes containing the standard samples into the standard sample grooves of the sample groove, uniformly lays the sample to be tested on the sample groove except the area of the standard sample grooves, so that the sample to be tested is uniformly laid around the standard samples, uniform sample preparation of the standard samples and the sample to be tested is realized, the device is convenient to assemble and disassemble, the standard samples can be repeatedly used, the method is simple, and the test efficiency is high.

Description

Technical Field

[0001] The invention belongs to the field of oil and gas exploration, and particularly relates to a sample preparation device and method suitable for measuring vitrinite reflectance using an imaging method. Background Art

[0002] Currently, there are two main methods for measuring vitrinite reflectance: photometry and imaging. The traditional photometry method measures the percentage of light intensity reflected from the vitrinite surface relative to the incident light intensity. Under an optical microscope with a fixed incident light intensity, the sample's reflectance is determined by comparing the photoelectric signal between the vitrinite in the sample and a standard sample of known reflectance (SY / T 5124-2012). Frequent calibration with standard samples is required during the test, which is time-consuming and inefficient, and prolonged observation through the eyepiece can easily fatigue the operator (Bai Xiangfei, 2011). The imaging method utilizes grayscale image analysis technology. By measuring the grayscale value of a standard vitrinite, a function is obtained that determines the relationship between the standard sample's reflectance and grayscale. A fixed area of ​​the sample is then scanned, and the grayscale value data is optimized and fitted with the standard sample's grayscale curve to determine the sample's vitrinite reflectance (Yang Yunfeng, 2017). Compared to the traditional photometry method, the tester does not need to stare at the eyepiece for a long time, allowing for on-screen operation and improved automation (Wang Wentao, 2003). However, since the grayscale value (reflected light intensity) decreases from the center of the image toward the surrounding areas (Wang Yue, 2017), only one vitrinite in the center of the field of view can be used for grayscale testing during testing. No points can be taken for test objects outside the center of the field of view. This requires obtaining a large number of grayscale photos for optimization, which increases the number of test steps and errors, and the test efficiency needs to be improved.

[0003] Therefore, there is a particular need for a sample preparation device and method with simple testing steps and high testing efficiency. Summary of the Invention

[0004] The object of the present invention is to provide a sample preparation device and method with simple testing steps and high testing efficiency.

[0005] To achieve the above-mentioned object, the present invention provides a sample preparation device suitable for measuring vitrinite reflectance by an imaging method, comprising: a sample stage, a sample slot is provided on the top of the sample stage, and the sample slot is used to hold a sample to be measured; a plurality of standard sample slots, and the plurality of standard sample slots are evenly arranged in the sample slots; and a plurality of standard sample tubes, each of the standard sample tubes is inserted in one of the standard sample slots, and the standard sample tubes are used to accommodate standard samples.

[0006] Optionally, the sample stage is circular in shape.

[0007] Optionally, the sample tank is square in shape.

[0008] Optionally, the plurality of standard sample grooves are uniformly arranged in an array in the entire sample groove, and the distance between every two adjacent standard sample grooves is the same.

[0009] Optionally, the to-be-tested sample is uniformly laid in the area between every two adjacent standard sample grooves in the sample groove.

[0010] Optionally, the standard sample groove is a cylindrical shape, and the standard sample tube is a circular tube.

[0011] Optionally, the diameter of the standard sample groove ranges from 115 um to 125 um.

[0012] Optionally, the distance between every two adjacent standard sample tubes ranges from 495 um to 505 um.

[0013] Optionally, the inner diameter of the standard sample tube ranges from 100 um to 105 um.

[0014] The application also provides a sample preparation method suitable for image method for determining vitrinite reflectance, which utilizes the sample preparation device suitable for image method for determining vitrinite reflectance, and the method comprises the following steps: step 1, loading standard samples into each standard sample tube, and uniformly laying a to-be-tested sample in the area between every two adjacent standard sample grooves in the sample groove; step 2, collecting images of the standard sample and the to-be-tested sample under the same central view; step 3, performing gray scale processing on the images to obtain the gray scale value of the standard sample and the gray scale value of the to-be-tested sample; step 4, calculating the reflectance of the to-be-tested sample based on the gray scale value of the standard sample, the gray scale value of the to-be-tested sample and the reflectance of the standard sample; and step 5, repeatedly performing steps 2 to 4 to obtain the reflectance of a plurality of to-be-tested samples and calculate the average value of the reflectance of the plurality of to-be-tested samples.

[0015] Optionally, the reflectance of the to-be-tested sample is calculated by the following formula:

[0016]

[0017] wherein R1 is the reflectance of the to-be-tested sample, G1 is the gray scale value of the to-be-tested sample, R0 is the reflectance of the standard sample, and G0 is the gray scale value of the standard sample.

[0018] The sample preparation device suitable for image method for determining vitrinite reflectance has the advantages that the standard sample tube loaded with the standard sample is inserted into the standard sample groove of the sample groove, and the to-be-tested sample is uniformly laid in the area of the sample groove except the standard sample groove, so that the to-be-tested sample is uniformly laid around the standard sample, and the standard sample and the to-be-tested sample are uniformly dispersed for sample preparation, the device is convenient to assemble and disassemble, the standard sample can be repeatedly used, the method is simple and efficient in testing.

[0019] The sample preparation method for determining vitrinite reflectivity by image method of the present application uses the sample preparation device described above to collect standard sample and sample to be tested under the same central view, and to obtain the gray value of the standard sample and the sample to be tested, and to calculate the reflectivity value of the sample to be tested from the linear relationship between the reflectivity value of the standard sample and the gray value, which is simple and has high measurement accuracy.

[0020] The present application has other characteristics and advantages that will be apparent from and / or set forth in more detail in the accompanying drawings and subsequent detailed description, which together serve to explain certain principles of the present application. BRIEF DESCRIPTION OF DRAWINGS

[0021] The above and other objects, features and advantages of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which like reference characters refer to like parts throughout the several views.

[0022] Figure 1 A top view of a sample preparation device for determining vitrinite reflectivity by image method according to one embodiment of the present application is shown.

[0023] Figure 2 A sectional view of a sample preparation device for determining vitrinite reflectivity by image method according to one embodiment of the present application is shown.

[0024] Figure 3 A partial enlarged view of the positional relationship between the sample to be tested and the standard sample of a sample preparation device for determining vitrinite reflectivity by image method according to one embodiment of the present application is shown.

[0025] Figure 4 A flow chart of a sample preparation method for determining vitrinite reflectivity by image method according to one embodiment of the present application is shown.

[0026] BRIEF DESCRIPTION OF DRAWINGS

[0027] 1, sample stage; 2, standard sample groove; 3, standard sample tube; 4, sample groove; 5, sample to be tested; 6, standard sample. DETAILED DESCRIPTION

[0028] Preferred embodiments of the present application will be described in more detail below. Although the following describes preferred embodiments of the present application, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present application is more thoroughly and completely conveyed to those skilled in the art, and so that the scope of the present application is fully conveyed to those skilled in the art.

[0029] According to the sample preparation device for measuring vitrinite reflectance by image method, the standard sample tube containing the standard sample is inserted into the standard sample groove of the sample groove, and the sample to be tested is uniformly laid on the area of the sample groove except the standard sample groove, so that the sample to be tested is uniformly laid around the standard sample, and the sample preparation of the standard sample and the sample to be tested is uniformly dispersed.

[0030] Specifically, the sample table is a light sheet base, a square part is arranged in the middle, and a groove with a downward concave of 1 mm is called a sample groove, which is used to carry the standard sample and the sample to be tested. The sample groove is also uniformly arranged with a plurality of standard sample grooves, each standard sample tube containing a standard sample is inserted into a standard sample groove, and the sample to be tested is uniformly laid around the standard sample groove, and the position of the standard sample is fixed to ensure the uniformity of the mixed standard sample and the sample to be tested.

[0031] The standard sample tube is a capillary column for containing the crushed standard sample. The capillary column has an inner diameter of 100 um and a wall thickness of 10 um. After the standard sample is crushed to a particle size of 50-100 um, it is injected into the capillary column, and then the capillary column is inserted into the standard sample groove. The top of the capillary column is flush with the top of the sample table.

[0032] According to the sample preparation device for measuring vitrinite reflectance by image method, the standard sample tube containing the standard sample is inserted into the standard sample groove of the sample groove, and the sample to be tested is uniformly laid on the area of the sample groove except the standard sample groove, so that the sample to be tested is uniformly laid around the standard sample, and the sample preparation of the standard sample and the sample to be tested is uniformly dispersed.

[0033] As an optional solution, the shape of the sample table is circular.

[0034] As an optional solution, the shape of the sample groove is square.

[0035] As an optional solution, the plurality of standard sample grooves are uniformly arranged in an array manner in the entire sample groove, and the distance between every two adjacent standard sample grooves is the same.

[0036] Specifically, the plurality of standard sample tubes are arranged in a multi-row and multi-column array form in the entire sample groove, that is, uniformly arranged in the entire sample groove along the transverse direction and the longitudinal direction. The shape of the plurality of sample tubes is the same as that of the sample groove, which is also square, and the distance between every two adjacent standard sample grooves is the same.

[0037] As an optional solution, the sample to be tested is uniformly laid in the area between every two adjacent standard sample grooves in the sample groove.

[0038] Specifically, the to-be-tested sample is uniformly laid on the area of the sample groove except for the plurality of standard sample grooves, that is, the to-be-tested sample is laid on the area of the sample groove between two adjacent standard sample grooves, and the to-be-tested sample is laid around each standard sample groove.

[0039] Alternatively, the standard sample groove is a cylindrical shape, and the standard sample tube is a circular tube.

[0040] Specifically, the standard sample groove is a cylindrical shape that is concave downward from the bottom surface of the sample groove, facilitating insertion of the standard sample tube.

[0041] Alternatively, the diameter of the standard sample groove ranges from 115 um to 125 um.

[0042] In an example, the aperture of the standard sample groove ranges from 120 um.

[0043] Alternatively, the spacing between two adjacent standard sample tubes ranges from 495 um to 505 um.

[0044] Specifically, the spacing between two adjacent standard sample tubes is preferably 500 um, ensuring that a group of standard samples and to-be-tested samples or a plurality of groups of adjacent standard samples and to-be-tested samples can be collected under the same central view.

[0045] Alternatively, the inner diameter of the standard sample tube ranges from 100 um to 105 um.

[0046] Specifically, the inner diameter of the standard sample tube is configured to be able to be inserted into the standard sample groove and to be able to accommodate the standard sample particles.

[0047] The application also provides a sample preparation method for determining vitrinite reflectance by the image method, which utilizes the sample preparation device for determining vitrinite reflectance by the image method. The method comprises the following steps: step 1, loading standard samples into each standard sample tube and uniformly laying to-be-tested samples between two adjacent standard sample grooves; step 2, collecting images of the standard samples and the to-be-tested samples under the same central view; step 3, performing gray scale processing on the images to obtain the gray scale values of the standard samples and the to-be-tested samples; step 4, calculating the reflectance of the to-be-tested sample based on the gray scale values of the standard samples, the gray scale values of the to-be-tested samples, and the reflectance of the standard samples; step 5, repeating steps 2 to 4 to obtain the reflectance of a plurality of to-be-tested samples and calculate the average value of the reflectance of the plurality of to-be-tested samples.

[0048] Specifically, compared with the traditional sample preparation method, the standard sample is mixed in the sample to be measured, so that the gray value of the sample to be measured and the standard sample can be obtained at the same time when the vitrinite reflectance is measured by the image method. A group or multiple groups of the sample to be measured and the standard sample in the same central field of view are selected for photographing when the gray value is measured. The reflectance value of the sample to be measured is calculated through the linear relationship between the reflectance value of the standard sample and the gray value. The images of different samples to be measured and standard samples are obtained by repeating the above steps, the average value of the reflectance of multiple samples to be measured is calculated, and the average value is taken as the final reflectance of the sample to be measured.

[0049] According to the exemplary embodiment, the sample preparation method for measuring vitrinite reflectance by the image method of the present application uses the above-mentioned sample preparation device to collect the standard sample and the sample to be tested under the same central field of view, and simultaneously obtains the gray value of the standard sample and the sample to be tested. The reflectance value of the sample to be tested is calculated through the linear relationship between the reflectance value of the standard sample and the gray value. The method is simple and has high measurement accuracy.

[0050] As an optional solution, the reflectance of the sample to be measured is calculated by the following formula:

[0051]

[0052] Wherein, R1 is the reflectance of the sample to be measured, G1 is the gray value of the sample to be measured, R0 is the reflectance of the standard sample, and G0 is the gray value of the standard sample.

[0053] Specifically, the reflectance value of the sample to be tested is calculated through the linear relationship between the reflectance value of the standard sample and the gray value.

[0054] Embodiment

[0055] Figure 1 A top view of a sample preparation device for measuring vitrinite reflectance by the image method according to an embodiment of the present application is shown. Figure 2 A sectional view of a sample preparation device for measuring vitrinite reflectance by the image method according to an embodiment of the present application is shown.

[0056] In combination Figure 1 And Figure 2 As shown in the figure, the sample preparation device for measuring vitrinite reflectance by the image method comprises a sample table 1, a sample groove 4 is arranged on the top of the sample table 1, and the sample groove 4 is used to carry the sample to be measured 5. A plurality of standard sample grooves 2 are uniformly arranged in the sample groove 4. A plurality of standard sample tubes 3 are inserted into one standard sample groove 2, and the standard sample tube 3 is used to contain the standard sample 6.

[0057] Wherein, the shape of the sample table 2 is circular.

[0058] The sample groove 4 is square in shape.

[0059] The plurality of standard sample grooves 2 are uniformly arranged in an array in the entire sample groove 4, and the distance between every two adjacent standard sample grooves 2 is the same.

[0060] The to-be-tested sample 5 is uniformly laid in the area between every two adjacent standard sample grooves 2 in the sample groove 4.

[0061] The standard sample groove 2 is cylindrical and recessed downward from the bottom surface of the sample groove 4; and the standard sample tube 3 is a circular tube.

[0062] The diameter of the standard sample groove 2 ranges from 115 um to 125 um.

[0063] The distance between every two adjacent standard sample tubes 3 ranges from 495 um to 505 um.

[0064] The inner diameter of the standard sample tube 3 ranges from 100 um to 105 um.

[0065] Take a kerogen sample (coal sample) as an example. According to the requirements for the particle diameter of rock samples in the industry standard “Method for Identification and Statistics of Whole Rock Optical Microscopic Components”, the sample is loaded into the sample groove and bonded with a curing agent. The sample groove is previously coated with a layer of release agent to facilitate the removal of the sample after testing. The standard sample commonly used in reflectance testing is selected, crushed, and then ground into particles with a particle size of about 100 um using a ball mill. The standard sample tube is loaded with the particles and firmly bonded with a curing agent, and then the standard sample tube is inserted into the standard sample groove. The entire sample groove is distributed in a square shape on the resin optical slice, with a side length of 20 mm x 20 mm. A standard sample groove is distributed every 500 um, and the to-be-tested sample can be filled between two standard sample grooves. In this way, the distribution can ensure that at least one standard sample particle and one to-be-tested sample particle will appear in each field of view under the largest visual field light field, fully ensuring the uniformity of the mixture, so as to measure the gray scale of the standard sample and the to-be-tested sample at the same time in the same field of view.

[0066] Example Two

[0067] Figure 3 A partial enlarged view of the positional relationship between the to-be-tested sample and the standard sample of the sample preparation device suitable for image method vitrinite reflectance determination according to an embodiment of the present application is shown. Figure 4 A flowchart of the sample preparation method suitable for image method vitrinite reflectance determination according to an embodiment of the present application is shown.

[0068] In combination Figure 3 and Figure 4As shown, the sample preparation method suitable for measuring vitrinite reflectance by the imaging method utilizes the sample preparation device suitable for measuring vitrinite reflectance by the imaging method described above, and the method comprises:

[0069] Step 1: Place the standard sample into each standard sample tube and evenly spread the sample to be tested in the area between two adjacent standard sample slots in the sample slot;

[0070] Step 2: Collect images of the standard sample and the sample to be tested under the same central field of view;

[0071] Step 3: Perform grayscale processing on the image to obtain the grayscale value of the standard sample and the grayscale value of the sample to be tested;

[0072] Step 4: Calculate the reflectivity of the sample to be tested based on the grayscale value of the standard sample, the grayscale value of the sample to be tested, and the reflectivity of the standard sample;

[0073] Step 5: Repeat steps 2 to 4 to obtain the reflectance of multiple samples to be tested, and calculate the average value of the reflectance of the multiple samples to be tested.

[0074] The reflectivity of the sample to be tested is calculated using the following formula:

[0075]

[0076] Among them, R1 is the reflectivity of the sample to be tested, G1 is the grayscale value of the sample to be tested, R0 is the reflectivity of the standard sample, and G0 is the grayscale value of the standard sample.

[0077] When testing grayscale, two adjacent groups in the same central field of view are selected to take pictures. Figure 3 Take two groups of adjacent particles as an example. The grayscale of the standard sample is measured to be G0, and the grayscale of the sample to be tested is G1. Since the reflectivity of the standard sample is known to be R0, there is a linear relationship between the grayscale Gray and the reflectivity Ro of the standard sample. The reflectivity R2 of the sample to be tested can be calculated through the three parameters of the grayscale values ​​G0 and G1 of the two and the reflectivity R0 of the standard sample. The reflectivity values ​​of multiple samples to be tested can be calculated in the same way, and the average value of the reflectivity values ​​of multiple samples to be tested can be calculated as the final reflectivity value of the sample to be tested.

[0078] While various embodiments of the present invention have been described above, the above description is intended to be illustrative, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A sample preparation method suitable for measuring vitrinite reflectance by an imaging method, using a sample preparation device suitable for measuring vitrinite reflectance by an imaging method, characterized in that: The device comprises: A sample stage, wherein a sample slot is provided on the top of the sample stage, and the sample slot is used to hold the sample to be tested; A plurality of standard sample slots, wherein the plurality of standard sample slots are evenly distributed in the sample slot; A plurality of standard sample tubes, each of which is inserted into one of the standard sample slots, and is used to accommodate a standard sample; Wherein, the shape of the sample stage is circular, and the shape of the sample tank is square; The plurality of standard sample slots are evenly arranged in an array throughout the sample slot, and the distance between any two adjacent standard sample slots is the same; The spacing between two adjacent standard sample tubes ranges from 495um to 505um, ensuring that a group of standard samples and samples to be tested, or multiple groups of adjacent standard samples and samples to be tested, can be collected in the same central field of view. The method comprises: Step 1: Place the standard sample into each standard sample tube and evenly spread the sample to be tested in the area between two adjacent standard sample slots in the sample slot; Step 2: Collect images of the standard sample and the sample to be tested under the same central field of view; Step 3: performing grayscale processing on the image to obtain the grayscale value of the standard sample and the grayscale value of the sample to be tested; Step 4: Calculating the reflectivity of the sample to be tested based on the grayscale value of the standard sample, the grayscale value of the sample to be tested, and the reflectivity of the standard sample; Step 5: Repeat steps 2 to 4 to obtain the reflectivity of multiple samples to be tested, and calculate the average value of the reflectivity of the multiple samples to be tested; The reflectivity of the sample to be tested is calculated using the following formula: Among them, R1 is the reflectivity of the sample to be tested, G1 is the grayscale value of the sample to be tested, R0 is the reflectivity of the standard sample, and G0 is the grayscale value of the standard sample.

2. The sample preparation method for measuring vitrinite reflectance by image method according to claim 1, wherein The sample to be tested is evenly spread in the area between every two adjacent standard sample grooves in the sample groove.

3. The sample preparation method for measuring vitrinite reflectance by image method according to claim 1, wherein The standard sample tank is cylindrical and is concave downward from the bottom surface of the sample tank; the standard sample tube is a round tube.

4. The sample preparation method for measuring vitrinite reflectance by image method according to claim 3, wherein: The diameter of the standard sample tank ranges from 115 μm to 125 μm.

5. The sample preparation method for measuring vitrinite reflectance by image method according to claim 4, wherein: The inner diameter of the standard sample tube ranges from 100 μm to 105 μm.

Images