Method for calculating coal rock gas adsorption capacity based on nuclear magnetic resonance T2 cutoff value

Abstract

This application discloses a method for calculating the adsorption capacity of coal shale gas based on the nuclear magnetic resonance (NMR) T2 cutoff value. The method includes: acquiring multiple coal shale samples and determining their ash content; performing NMR testing on the coal shale samples to obtain the NMR T2 spectrum under saturated water conditions; centrifuging the saturated coal shale samples to obtain the NMR T2 spectrum under bound water conditions; obtaining the NMR T2 cutoff value of the coal shale samples based on the NMR T2 spectrum; testing the adsorbed gas content of the coal shale samples to obtain their adsorbed gas content; establishing an adsorbed gas content calculation model through regression analysis; and inputting the ash content and NMR T2 cutoff value of the coal shale sample into the adsorbed gas content calculation model to obtain the adsorbed gas content of the coal shale sample. This invention reduces the high cost of experiments and significantly improves the efficiency of coal shale gas exploration and development.

Description

Technical Field

[0001] This application relates to the field of geological exploration technology, and more specifically, to a method for calculating the amount of coal rock gas adsorption based on the nuclear magnetic resonance T2 cutoff value. Background Technology

[0002] Coal shale gas, as an emerging and important sector in the unconventional oil and gas field, is undergoing vigorous exploration, development, and remediation. Assessing the gas content of coal is a crucial step in coal shale gas resource exploration and development. Based on its occurrence mode, coal shale gas can be divided into adsorbed gas and free gas. Adsorbed gas refers to gas preserved in an adsorbed state on the surface of organic matter particles. It is particularly abundant in deep coal shale gas reservoirs. Utilizing the rich microporous structure of the coal matrix surface, it is adsorbed onto the inner walls of the pores through intermolecular forces such as van der Waals forces and hydrogen bonds. It typically accounts for 70% to 90% of the total coal shale gas, making it the main contributor to coal shale gas resources. Since coal shale gas mainly exists underground in the form of adsorbed gas within coal seams, calculating the underground adsorption capacity of coal shale gas is of great significance for assessing the potential of deep coal shale gas resources, selecting favorable target areas, and formulating development plans.

[0003] Currently, the testing of methane adsorption content in coal mainly relies on methane adsorption experiments under high temperature and high pressure conditions. Commonly used methane adsorption experimental methods under these conditions include the volumetric method, the gravimetric method, and the more advanced nuclear magnetic resonance (NMR) technique. Specifically, the volumetric method calculates the adsorption amount by precisely monitoring the pressure change of the gas in a fixed-volume system; the gravimetric method uses a high-precision balance to directly measure the minute mass difference in the coal sample before and after methane adsorption, thus accurately quantifying the adsorption amount; and NMR technology, by capturing the unique response of methane molecules in a magnetic field during adsorption, can deeply and intuitively show the distribution of methane molecules in micropores, providing a new perspective for exploring the behavior of methane adsorption in coal. However, these experimental methods have drawbacks such as high experimental requirements and high testing costs.

[0004] This application employs a more convenient and faster water-saturated nuclear magnetic resonance experiment, combined with the coal quality characteristics of coal, to establish a calculation method for coal gas adsorption based on the nuclear magnetic resonance T2 cutoff value. Its advantages are simpler experimental conditions and more affordable experimental costs, which is of great significance for the large-scale exploration and development of coal gas. Summary of the Invention

[0005] To address the aforementioned issues, this application provides a method for calculating the amount of coal rock gas adsorbed based on the nuclear magnetic resonance T2 cutoff value, aiming to solve the problems of stringent testing conditions and high testing costs for coal rock adsorbed gas content.

[0006] The first aspect of this invention provides a method for calculating the adsorption amount of coal shale gas based on the nuclear magnetic resonance T2 cutoff value, comprising:

[0007] Multiple coal and rock samples were obtained, and the ash content of the coal and rock samples was determined.

[0008] The coal and rock samples were subjected to water-saturated nuclear magnetic resonance (NMR) tests to obtain the NMR T2 spectrum under water saturation. The coal and rock samples under water saturation were then centrifuged to obtain the NMR T2 spectrum under bound water conditions. Based on the NMR T2 spectra under water saturation and bound water conditions, the NMR T2 cutoff value of the coal and rock samples was obtained.

[0009] The adsorbed gas content of the coal and rock samples was tested to obtain the adsorbed gas content of the coal and rock samples; based on the ash content, nuclear magnetic resonance T2 cutoff value and adsorbed gas content of the coal and rock samples, an adsorbed gas content calculation model was established through regression analysis.

[0010] The ash content and nuclear magnetic resonance T2 cutoff value of the coal and rock sample to be tested are input into the adsorbed gas content calculation model to obtain the adsorbed gas content of the coal and rock sample to be tested.

[0011] In one optional implementation, the nuclear magnetic resonance (NMR) T2 cutoff value of the coal and rock samples is obtained based on the NMR T2 spectrum under saturated water and bound water conditions. The specific steps are as follows:

[0012] The cumulative porosity curve of saturated water was plotted based on the nuclear magnetic resonance T2 spectrum under the saturated water state.

[0013] The cumulative porosity curve of bound water was plotted based on the nuclear magnetic resonance T2 spectrum of the bound water state.

[0014] At the maximum value of the cumulative porosity curve of bound water, draw a straight line parallel to the nuclear magnetic resonance T2 time axis, which intersects the cumulative porosity curve of saturated water at a point;

[0015] Draw a perpendicular line from the intersection point to the T2 time axis of the nuclear magnetic resonance (NMR). The NMR T2 value corresponding to the intersection point of this perpendicular line and the T2 time axis is the NMR T2 cutoff value.

[0016] In one optional embodiment, the calculation model for the adsorbed gas content is a univariate regression equation between ash content and adsorbed gas content:

[0017]

[0018] in, The content of adsorbed gas in coal and rock. This refers to the ash content.

[0019] In one optional embodiment, the calculation model for the adsorbed gas content is a univariate regression equation between the nuclear magnetic resonance T2 cutoff value and the adsorbed gas content:

[0020]

[0021] in, The content of adsorbed gas in coal and rock. This is the T2 cutoff value for nuclear magnetic resonance.

[0022] In one optional embodiment, the calculation model for the adsorbed gas content is a binary regression equation of ash content and NMR T2 cutoff value with adsorbed gas content:

[0023]

[0024] in, The content of adsorbed gas in coal and rock. Ash content, This is the T2 cutoff value for nuclear magnetic resonance.

[0025] In one optional embodiment, before performing saturated nuclear magnetic resonance testing on the coal and rock sample, a sample preparation step is further included: making the coal and rock sample into a plunger with a diameter of 25 mm and a height of 50 mm.

[0026] In one alternative embodiment, the centrifugation process is carried out at a pressure of 1.38 MPa for 90 minutes.

[0027] A second aspect of this invention provides an apparatus for calculating the adsorption amount of coalbed methane based on the nuclear magnetic resonance T2 cutoff value, the apparatus comprising:

[0028] The data acquisition module is configured to acquire multiple coal and rock samples and determine the ash content of the coal and rock samples.

[0029] The T2 cutoff value calculation module is configured to perform saturated NMR testing on the coal and rock samples to obtain the NMR T2 spectrum under saturated water conditions, centrifuge the coal and rock samples under saturated water conditions to obtain the NMR T2 spectrum under bound water conditions, and obtain the NMR T2 cutoff value of the coal and rock samples based on the NMR T2 spectrum under saturated water conditions and the NMR T2 spectrum under bound water conditions.

[0030] The model building module is configured to test the adsorbed gas content of the coal and rock samples to obtain the adsorbed gas content of the coal and rock samples; based on the ash content, nuclear magnetic resonance T2 cutoff value and adsorbed gas content of the coal and rock samples, an adsorbed gas content calculation model is established through regression analysis.

[0031] The prediction module is configured to input the ash content and nuclear magnetic resonance T2 cutoff value of the coal and rock sample to be tested into the adsorbed gas content calculation model to obtain the adsorbed gas content of the coal and rock sample to be tested.

[0032] A third aspect of the present invention provides an electronic device, characterized in that it includes: a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, it implements a method for calculating the amount of coal gas adsorption based on the nuclear magnetic resonance T2 cutoff value.

[0033] A fourth aspect of the present invention provides a computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, a method for calculating the amount of coal gas adsorption based on the nuclear magnetic resonance T2 cutoff value.

[0034] This application has at least the following advantages or beneficial effects:

[0035] This application provides a more cost-effective and convenient method for calculating the content of adsorbed gas in coal and rock. By utilizing industrial component analysis and saturated water nuclear magnetic resonance experimental parameters commonly used in coal and rock gas research, it avoids conducting expensive and demanding high-pressure isothermal adsorption experiments. The content of adsorbed gas in coal and rock can be calculated using this formula, which is beneficial for conducting large-area, multi-well-area, and multi-sample analysis of adsorbed gas content in coal and rock, and is of great significance for large-scale exploration and development of coal and rock gas. Attached Figure Description

[0036] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a flowchart of a method for calculating the adsorption amount of coal rock gas based on the nuclear magnetic resonance T2 cutoff value, as proposed in an embodiment of this application;

[0038] Figure 2 This is a diagram illustrating a method for calculating the T2 cutoff value of nuclear magnetic resonance according to an embodiment of this application;

[0039] Figure 3 (a) is a linear regression diagram of ash content versus adsorbed gas content proposed in an embodiment of this application. Figure 3 (b) is a linear regression diagram of the nuclear magnetic resonance T2 cutoff value and adsorbed gas content proposed in an embodiment of this application;

[0040] Figure 4 This is a binary regression analysis graph proposed in one embodiment of this application;

[0041] Figure 5 This is a binary regression linear fitting graph proposed in one embodiment of this application;

[0042] Figure 6 This is a structural diagram of a device for calculating the adsorption amount of coal rock gas based on the nuclear magnetic resonance T2 cutoff value, according to an embodiment of this application.

[0043] Figure 7 This is a schematic diagram of an electronic device according to this application. Detailed Implementation

[0044] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0045] Please refer to Figure 1 , Figure 1 This is a flowchart illustrating a method for calculating coalbed methane adsorption based on the T2 cutoff value of nuclear magnetic resonance, as proposed in an embodiment of this application. Figure 1 As shown, a method for calculating the adsorption amount of coal shale gas based on the nuclear magnetic resonance T2 cutoff value includes:

[0046] S100: Obtain multiple coal and rock samples and determine the ash content of the coal and rock samples;

[0047] In this embodiment, coal core samples of different coal ranks from the Benxi Formation of the Carboniferous system were collected from the Mizhi, Shenmu, and Nalinhe areas of the Ordos Basin. Each sample was divided into three parts for testing of coal industrial composition, adsorbed gas content, and saturated water nuclear magnetic resonance. Industrial analysis was also conducted on the samples to obtain their ash content.

[0048] S200: Perform saturated water nuclear magnetic resonance (NMR) testing on the coal and rock sample to obtain the NMR T2 spectrum under saturated water conditions; centrifuge the coal and rock sample under saturated water conditions to obtain the NMR T2 spectrum under bound water conditions; based on the NMR T2 spectrum under saturated water conditions and the NMR T2 spectrum under bound water conditions, obtain the NMR T2 cutoff value of the coal and rock sample.

[0049] In this embodiment, before performing saturated nuclear magnetic resonance testing on the coal and rock samples, a sample preparation step is also included:

[0050] S210: Prepare a plunger with a diameter of 25 mm and a height of 50 mm from the coal and rock sample; number the coal sample after preparation, and then put the coal sample into a drying oven for drying at 60°C until the weight of the coal sample stops changing.

[0051] S220: All coal and rock samples were saturated with water for 24 hours under vacuum conditions (vacuum pressure of -0.1MPa). After saturation, nuclear magnetic resonance analysis was carried out to obtain the nuclear magnetic resonance T2 spectrum under saturated water conditions.

[0052] S230: After the saturated water test, the coal and rock samples were centrifuged at 1.38 MPa for 90 minutes to convert the samples into bound water state. Then, nuclear magnetic resonance analysis was performed to obtain the nuclear magnetic resonance T2 spectrum in the bound water state.

[0053] S240: As Figure 2 As shown, based on the nuclear magnetic resonance T2 spectrum under saturated water and bound water conditions, the nuclear magnetic resonance T2 cutoff value of the coal and rock samples is obtained. The specific steps are as follows:

[0054] S241: Plot the cumulative porosity curve of saturated water based on the nuclear magnetic resonance T2 spectrum under the saturated water state;

[0055] S242: Plot the cumulative porosity curve of bound water based on the nuclear magnetic resonance T2 spectrum of the bound water state;

[0056] S243: Draw a straight line parallel to the nuclear magnetic resonance T2 time axis at the maximum value of the cumulative porosity curve of the bound water, and the straight line intersects the cumulative porosity curve of the saturated water at a point;

[0057] S244: Draw a perpendicular line from the intersection point to the T2 time axis of the nuclear magnetic resonance (NMR). The NMR T2 value corresponding to the intersection point of this perpendicular line and the T2 time axis is the NMR T2 cutoff value.

[0058] The results of the analysis and testing of the coal and rock samples are shown in Table 1:

[0059] Table 1

[0060]

[0061] S300: The adsorbed gas content of the coal and rock sample is tested to obtain the adsorbed gas content of the coal and rock sample; based on the ash content, nuclear magnetic resonance T2 cutoff value and adsorbed gas content of the coal and rock sample, an adsorbed gas content calculation model is established through regression analysis;

[0062] In this embodiment, the coal sample was prepared with a particle size of 0.25 mm to 0.18 mm (60 mesh to 80 mesh) for coal rock adsorption gas content testing. The results of the high-pressure isothermal adsorption test for methane in the coal rock sample are shown in Table 2.

[0063] Table 2

[0064]

[0065] Regression results as follows Figure 3 As shown in (a), the calculation model for the adsorbed gas content is a univariate regression equation between the ash content and the adsorbed gas content:

[0066] (R) 2 =0.84)

[0067] in, The content of adsorbed gas in coal and rock. This refers to the ash content.

[0068] Regression results as follows Figure 3 As shown in (b), the calculation model for the adsorbed gas content is a univariate regression equation between the nuclear magnetic resonance T2 cutoff value and the adsorbed gas content:

[0069] (R) 2 =0.91)

[0070] in, The content of adsorbed gas in coal and rock. This is the T2 cutoff value for nuclear magnetic resonance.

[0071] The calculation model for the adsorbed gas content is a binary regression equation between ash content, NMR T2 cutoff value, and adsorbed gas content:

[0072] (R) 2 =0.93)

[0073] in, The content of adsorbed gas in coal and rock. Ash content, This is the T2 cutoff value for nuclear magnetic resonance.

[0074] Regression results as follows Figure 4 , Figure 5 As shown, the bivariate regression equation R 2 The value is significantly larger than that of the univariate regression equation, the predicted value is very close to the actual value, and the regression result is reliable.

[0075] S400: Input the ash content and nuclear magnetic resonance T2 cutoff value of the coal and rock sample to be tested into the adsorbed gas content calculation model to obtain the adsorbed gas content of the coal and rock sample to be tested.

[0076] In this embodiment, three coal and rock samples were collected, and industrial composition, saturated water nuclear magnetic resonance, and high-pressure methane isothermal adsorption tests were conducted. The adsorbed gas content was calculated using the calculation method of this patent, and the results are shown in Table 3.

[0077] Table 3

[0078]

[0079] The measured adsorbed gas content of sample 1 was 15.561 mg / L. 3 / t, the adsorbed gas content calculated by the method of this patent is 15.314m. 3 / t, error 1.59%; measured adsorbed gas content of sample 2 was 13.412m. 3 / t, the adsorbed gas content calculated by the method of this patent is 13.452m. 3 / t, error 0.30%; measured adsorbed gas content of sample 3 was 13.156m³. 3 / t, the adsorbed gas content calculated by the method of this patent is 13.326m. 3 / t, with an error of 1.29%. The error in the coal and rock adsorbed gas content calculated by this method is less than 2%. The technology of this invention is accurate and reliable, and the calculation effect is good.

[0080] Furthermore, the centrifugation process is carried out at a pressure of 1.38 MPa for 90 minutes.

[0081] Please refer to Figure 6 , Figure 6 This is a structural diagram of a device for calculating coal gas adsorption based on the T2 cutoff value of nuclear magnetic resonance, as proposed in an embodiment of this application. Figure 6 As shown in the figure, this disclosure also provides a device for calculating the adsorption amount of coalbed methane based on the nuclear magnetic resonance T2 cutoff value. The device includes: a data acquisition module 601, a T2 cutoff value calculation module 602, a model construction module 603, and a prediction module 604; wherein,

[0082] The data acquisition module 601 is configured to acquire multiple coal and rock samples and determine the ash content of the coal and rock samples.

[0083] The T2 cutoff value calculation module 602 is configured to perform water-saturated nuclear magnetic resonance (NMR) testing on the coal and rock sample to obtain the NMR T2 spectrum under water saturation, centrifuge the coal and rock sample under water saturation to obtain the NMR T2 spectrum under bound water; and obtain the NMR T2 cutoff value of the coal and rock sample based on the NMR T2 spectrum under water saturation and bound water.

[0084] The model building module 603 is configured to test the adsorbed gas content of the coal and rock samples to obtain the adsorbed gas content of the coal and rock samples; based on the ash content, nuclear magnetic resonance T2 cutoff value and adsorbed gas content of the coal and rock samples, an adsorbed gas content calculation model is established through regression analysis.

[0085] The prediction module 604 is configured to input the ash content and nuclear magnetic resonance T2 cutoff value of the coal and rock sample to be tested into the adsorbed gas content calculation model to obtain the adsorbed gas content of the coal and rock sample to be tested.

[0086] This disclosure also provides an electronic device, please refer to... Figure 7 , Figure 7 This is a schematic diagram of an electronic device illustrated in an embodiment of this disclosure. For example... Figure 7 As shown, the electronic device 100 includes a memory 110 and a processor 120. The memory 110 and the processor 120 are connected via a bus for communication. The memory 110 stores a computer program that can run on the processor 120 to implement the steps in the method for calculating the amount of coal gas adsorption based on the nuclear magnetic resonance T2 cutoff value disclosed in this embodiment.

[0087] The disclosed embodiments also provide a computer-readable storage medium that, when the instructions in the computer-readable storage medium are executed by a processor of a computer device, enables the computer device to perform the steps in the method for calculating coalbed methane adsorption based on nuclear magnetic resonance T2 cutoff values ​​as described in the embodiments of this disclosure.

[0088] In summary, this application, by utilizing industrial component analysis data and saturated water NMR experimental parameters conventionally available in coal shale gas research, cleverly avoids the high cost and stringent experimental conditions of traditional high-pressure isothermal adsorption experiments. Based on this method, the adsorption capacity of coal shale gas can be calculated using a simple formula, significantly reducing experimental costs and technical barriers. This method is particularly suitable for large-scale, multi-well-area, and multi-sample coal shale gas adsorption capacity analysis, and can significantly improve the efficiency of coal shale gas exploration and development, possessing significant application value and significance for promoting large-scale coal shale gas exploration and development.

[0089] This application describes embodiments with reference to flowchart illustrations and / or block diagrams of methods, apparatuses, electronic devices, and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0090] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1The function specified in one or more boxes.

[0091] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0092] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0093] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0094] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0095] The above provides a detailed description of a method for calculating coalbed methane adsorption based on the T2 cutoff value of nuclear magnetic resonance. Specific examples have been used to illustrate the principle and implementation of this application. The description of the above embodiments is only for the purpose of helping to understand the method and its core ideas. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A method for calculating the amount of coal rock gas adsorption based on a T2 cutoff value of nuclear magnetic resonance, characterized in that, include: Multiple coal and rock samples were obtained, and the ash content of the coal and rock samples was determined. The coal and rock samples were subjected to water-saturated nuclear magnetic resonance (NMR) tests to obtain the NMR T2 spectrum under water saturation. The coal and rock samples under water saturation were then centrifuged to obtain the NMR T2 spectrum under bound water conditions. Based on the NMR T2 spectra under water saturation and bound water conditions, the NMR T2 cutoff value of the coal and rock samples was obtained. The adsorbed gas content of the coal and rock samples was tested to obtain the adsorbed gas content of the coal and rock samples; based on the ash content, nuclear magnetic resonance T2 cutoff value and adsorbed gas content of the coal and rock samples, an adsorbed gas content calculation model was established through regression analysis. The ash content and nuclear magnetic resonance T2 cutoff value of the coal and rock sample to be tested are input into the adsorbed gas content calculation model to obtain the adsorbed gas content of the coal and rock sample to be tested. Based on the nuclear magnetic resonance T2 spectra under saturated water and bound water conditions, the nuclear magnetic resonance T2 cutoff values ​​of coal and rock samples are obtained. The specific steps are as follows: The cumulative porosity curve of saturated water was plotted based on the nuclear magnetic resonance T2 spectrum under the saturated water state. The cumulative porosity curve of bound water was plotted based on the nuclear magnetic resonance T2 spectrum of the bound water state. At the maximum value of the cumulative porosity curve of bound water, draw a straight line parallel to the nuclear magnetic resonance T2 time axis, which intersects the cumulative porosity curve of saturated water at a point; Draw a perpendicular line from the intersection point to the T2 time axis of the nuclear magnetic resonance (NMR). The NMR T2 value corresponding to the intersection point of this perpendicular line and the T2 time axis is the NMR T2 cutoff value. Before performing saturated nuclear magnetic resonance testing on the coal and rock samples, a sample preparation step is also included: the coal and rock samples are made into plungers with a diameter of 25 mm and a height of 50 mm. The centrifugation process was carried out at a pressure of 1.38 MPa for 90 minutes.

2. The method for calculating the coal rock gas adsorption capacity based on the T2 cutoff value of nuclear magnetic resonance according to claim 1, characterized in that, The calculation model for the adsorbed gas content is a univariate regression equation between ash content and adsorbed gas content: in, The content of adsorbed gas in coal and rock. This refers to the ash content.

3. The method for calculating coalbed methane adsorption based on nuclear magnetic resonance T2 cutoff value according to claim 2, characterized in that, The calculation model for the adsorbed gas content is a univariate regression equation between the nuclear magnetic resonance T2 cutoff value and the adsorbed gas content: in, The content of adsorbed gas in coal and rock. This is the T2 cutoff value for nuclear magnetic resonance.

4. The method for calculating coal gas adsorption based on the nuclear magnetic resonance T2 cutoff value according to claim 1, characterized in that, The calculation model for the adsorbed gas content is a binary regression equation between ash content, NMR T2 cutoff value, and adsorbed gas content: in, The content of adsorbed gas in coal and rock. Ash content, This is the T2 cutoff value for nuclear magnetic resonance.

5. An apparatus for performing the method for calculating the adsorption amount of coal shale gas based on the nuclear magnetic resonance T2 cutoff value as described in any one of claims 1-4, characterized in that, The device includes: The data acquisition module is configured to acquire multiple coal and rock samples and determine the ash content of the coal and rock samples. The T2 cutoff value calculation module is configured to perform saturated NMR testing on the coal and rock samples to obtain the NMR T2 spectrum under saturated water conditions, centrifuge the coal and rock samples under saturated water conditions to obtain the NMR T2 spectrum under bound water conditions, and obtain the NMR T2 cutoff value of the coal and rock samples based on the NMR T2 spectrum under saturated water conditions and the NMR T2 spectrum under bound water conditions. The model building module is configured to test the adsorbed gas content of the coal and rock samples to obtain the adsorbed gas content of the coal and rock samples; based on the ash content, nuclear magnetic resonance T2 cutoff value and adsorbed gas content of the coal and rock samples, an adsorbed gas content calculation model is established through regression analysis; The prediction module is configured to input the ash content and nuclear magnetic resonance T2 cutoff value of the coal and rock sample to be tested into the adsorbed gas content calculation model to obtain the adsorbed gas content of the coal and rock sample to be tested.

6. An electronic device, characterized in that, include: A processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor, when executing the program, implements the method for calculating coalbed methane adsorption based on nuclear magnetic resonance T2 cutoff value as described in any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the method for calculating coalbed methane adsorption based on the nuclear magnetic resonance T2 cutoff value as described in any one of claims 1 to 4.

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