A post-mining belt transportation carbon emission detection device and detection method

Abstract

The application discloses a kind of post-mining belt transport carbon emission detection device and method, belong to coal mine gas monitoring field.The device includes test bin, coal sample supply bin, coal sample extraction pipe, spiral conveying device and gas concentration sensor;Test bin two ends are connected with coal sample supply bin and coal sample extraction pipe respectively, and spiral conveying device and four gas concentration sensors are arranged in bin.The method determines in-situ gas content Q by underground sampling, dynamically monitors after preparing standard coal sample, establishes gas concentration time relationship and coal sample residual gas volume time relationship, obtains the function of gas concentration and overall coal sample gas content by correlation, and calculates gas escape amount δ.The application realizes real-time online carbon emission monitoring in belt transport section, is strong against working condition interference, and fills the detection technology blank of the process section.

Description

Technical Field

[0001] This invention belongs to the field of coal mine gas emission monitoring technology, specifically relating to a carbon emission detection device and method for post-mine belt conveyor. Background Technology

[0002] With the continuous advancement of national initiatives for green and zero-carbon mine construction, carbon emission management in coal mining enterprises has gradually shifted from extensive statistical methods to refined, digitalized, and life-cycle management. Accurately grasping the total amount and distribution of carbon emissions from coal mines has significant social and economic benefits for achieving the goal of "near-zero emissions" in coal mines. However, the carbon emission monitoring technologies in the coal mining industry are currently generally lacking, especially in the crucial process of transporting coal from underground mining to the coal washing plant via conveyor belts; carbon emission monitoring methods for this stage are almost nonexistent. This process is crucial and urgently needs improvement because after coal is mined underground, the rate of gas emission (the main greenhouse gas emitting carbon) in the coal seam reaches its peak due to pressure release, surface exposure, and the disturbance caused by continuous conveyor belt transport. Especially when the conveyor belt transport distance is long, the contact time between the coal surface and the atmosphere increases, significantly increasing the amount of gas emitted. Therefore, accurate detection of gas emission in this transport section is a vital indicator in the carbon emission assessment of the entire life cycle of coal mining. Existing monitoring methods cannot perform real-time, dynamic, "in-situ" measurements during conveyor belt transport, resulting in long-term missing or severely distorted carbon emission data for this stage.

[0003] Current methods for detecting carbon emissions from coal conveyor belts in mines typically employ a sampling-grinding-residual emission measurement approach. However, this method has drawbacks: the grinding process is irreversible, leading to inconsistencies between samples; furthermore, the anisotropic nature of gas storage within coal results in significant differences in residual gas measurements, sometimes even causing data inversion between samples. Therefore, there is an urgent need for a device and method that can achieve continuous and dynamic detection without damaging the overall sample structure. Summary of the Invention

[0004] The technical problem to be solved by this invention is to provide a simple, low-cost, easy-to-operate, and scientifically sound carbon emission detection device and method for post-mine belt conveyor transport. The specific technical solution is as follows: In a first aspect, the present invention provides a carbon emission detection device for conveyor belt transport in mines, characterized in that: it includes a test chamber 1, one end of which is connected to a coal sample supply chamber 2 and the other end is connected to a coal sample extraction pipe 3; a spiral transport device 4 is provided in both the test chamber 1 and the coal sample supply chamber 2; and a gas concentration sensor 5 is provided inside the test chamber 1.

[0005] Furthermore, a spiral conveyor 4 is provided inside the coal sample supply bin 2; two spiral conveyor 4 are arranged side by side inside the test bin 1, respectively located on both sides of the spiral conveyor 4 inside the coal sample supply bin 2.

[0006] Furthermore, there are four gas concentration sensors 5, which are respectively set at the four corners of the test chamber 1, at a height that is the middle position between the upper surface of the coal sample and the top of the test chamber 1.

[0007] Furthermore, the test chamber 1 and the coal sample supply chamber 2 are rectangular parallelepiped structures.

[0008] Furthermore, the length, width and height of the test chamber 1 and the coal sample supply chamber 2 are 0.8m×0.5m×0.3m and 0.4m×0.5m×0.3m, respectively. Secondly, the present invention provides a detection method using any one of the following mining belt conveyor carbon emission detection devices, comprising the following steps: (A) First, drill horizontally into the underground working face to a depth of 0.5m. Take 10 samples from the mining area at intervals of 3-5m. Seal and wrap each sample, with a weight of 1kg. After crushing, determine the gas content of each sample in the laboratory. Use box plot analysis to obtain the gas content per kg of coal, denoted as Q. (B) Take 100 kg of coal sample from a depth of 0.5 m in the underground working face, crush it to completely release its gas content, and then inject the required gas into the coal sample through the gas supply system. The injection amount is controlled to ensure that the coal sample and gas reach a balance. Take 1 kg of the prepared coal sample each time and test its gas content in the laboratory. Test it three times in total. If the gas content per kg of coal sample is greater than Q in each of the three consecutive tests, it is considered qualified. Take 90 kg of the remaining coal sample and use it as the original material for the experiment. If the gas content per kg of coal sample is not greater than Q in each of the seven tests, start this step again. (C) The carbon emission detection device of the post-mine belt conveyor is used for detection: 60 kg of the processed coal sample is placed in test chamber 1, and the remaining 30 kg is placed in coal sample replenishment chamber 2, ensuring that the chamber is basically flat; the spiral conveyor device 4 rotates at a constant speed to ensure that 1 kg of coal sample is transported out every 2 minutes. For each mass of coal sample taken out of test chamber 1, the coal sample replenishment chamber 2 replenishes the corresponding mass of coal sample into test chamber 1, and the gas content inside test chamber 1 is monitored; the relationship between gas concentration C and time t and the relationship between the residual gas content D inside 1 kg of coal sample and time t are obtained; with time t as the independent variable, the relationship function between the average gas concentration at the gas concentration sensor 5 and the overall gas content of the coal sample is obtained; then the gas escape amount δ is calculated.

[0009] Further, in step (A), the obtained 1kg sample is crushed into granules. More than 97% of the crushed coal sample has a particle size of more than 0.20mm. After drying at 40℃ and normal temperature and pressure for 3 hours, the gas content of each group is calculated, and the data is analyzed using box plots.

[0010] Furthermore, in step (B), more than 97% of the pulverized coal sample has a particle size of 0.20 mm or larger. It is dried at 40°C under normal temperature and pressure for 3 hours to completely release its gas content. The gas supply system includes a gas cylinder, a pressure regulator, pipelines, and flow control equipment. The required gas is slowly injected into the sealed container containing the coal sample, ensuring that the gas injection rate is controlled at 60~80 ml / min and the injection pressure is controlled within 0.8 atm. The experimental conditions are kept stable, and the injection process lasts for more than 12 hours to ensure that the coal sample and gas reach a state of equilibrium.

[0011] Further, in step (C), the average value of the gas concentration data from the four gas concentration sensors 5 is calculated to obtain the relationship between the gas concentration C monitored at the fixed point and time t under a test duration of 60 minutes, i.e., relationship function one: ; Where C is the methane concentration monitored at a fixed point, in cm³ / g; a1 is the methane diffusion correction coefficient for the coal sample, with a value of 1.3185; 60Q is the total methane content in the coal body, in cm³; b is the temperature correction coefficient, which is determined as follows: when T < 5℃, b = 1; when 5℃ ≤ T < 25℃, b = 1 + (T - 5) / 4; when T ≥ 25℃, b = 7; t is the time for normal methane escape, in min; m1 is the compensation coefficient for the degree of coal sample pulverization, which is determined as follows: when the pulverized particle size d < 0.10mm, m1 = 4; when 0.10mm ≤ d < 0.40mm, m1 = 4 - (d - 0.10) / 0.10; when d ≥ 0.40mm, m1 = 1. The experiment involved taking 1 kg of coal samples every 2 minutes and measuring the gas content of each sample. After taking 30 sets of coal samples, the experiment was stopped. A smooth curve was plotted based on the 30 sets of data to obtain the relationship between the residual gas content D in 1 kg of coal sample and time t, i.e., relationship function two: ; Where D represents the residual gas content inside 1 kg of coal sample, in cm³; a2 is the gas content correction coefficient of coal sample, with a value of 2.0232; m2 is the coal sample structure correction coefficient, with a value of 0.2637; and t is the time for normal gas escape, in min.

[0012] Further, in step (C), relational function one and relational function two are correlated with time t as the independent variable to obtain relational function three between the average gas concentration at gas concentration sensor 5 and the overall gas content of the coal sample: ; Where D represents the residual gas content inside 1 kg of coal sample, in cm³; K represents the total gas content of the coal body, i.e., 60Q, in cm³; b is the temperature correction coefficient, which is determined as follows: when T < 5℃, b = 1; when 5℃ ≤ T < 25℃, b = 1 + (T - 5) / 4; when T ≥ 25℃, b = 7; e is the base of the natural logarithm, with a value of 2.718; r is the coal dryness correction coefficient, with a value of 0.2; C is the gas concentration monitored at fixed points, in cm³ / g; and m is the coal pulverization correction coefficient, with a value of 10.

[0013] Further, in step (C), based on the total gas content of the coal body (60Q) and the residual gas content (D) inside 1 kg of coal sample, the gas escape amount (δ) is calculated: ; Wherein, 60Q is the total gas content of the coal body, in cm³; D is the residual gas content inside 1kg coal sample, in cm³; and 60D is the total residual gas content of 60kg coal sample, in cm³.

[0014] Compared with the prior art, the beneficial technical effects of this invention are reflected in: First, it has a compact structure, low energy consumption, and is suitable for belt conveyor scenarios. This invention forms a dynamic supply system through a coal sample replenishment bin, a test bin, and a spiral conveyor device. It eliminates the need for frequent coal sample crushing, and the device consists of only conventional mechanical parts, resulting in low cost and low energy consumption. It can be directly deployed on existing belt conveyor lines.

[0015] Secondly, it enables real-time online carbon emission monitoring of the belt conveyor section. This invention can collect data on the change of gas concentration in the test chamber over time in real time and continuously measure the residual gas content of coal samples, filling the technological gap in carbon emission monitoring of the process from underground coal to coal washing plant via belt conveyor.

[0016] Third, it has strong resistance to interference from operating conditions through the inversion of the difference between the beginning and end of the coal seam. Regardless of the process, wind speed, vibration or temperature changes that a unit of coal seam has encountered before, this invention can invert the change in gas content inside the coal seam (i.e., escape amount δ) by measuring the gas concentration difference between the sensors at the beginning and end of the coal seam, and directly output the gas escape amount of that process segment. It is not affected by fluctuations in external environmental conditions, and the data calculation process can be reproduced. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the carbon emission detection device for post-mine belt conveyor transport according to the present invention; Figure 2 for Figure 1 A top-view structural diagram.

[0018] In the diagram: 1-Test chamber, 2-Coal sample supply chamber, 3-Coal sample extraction pipe, 4-Spiral conveyor device, 5-Gas concentration sensor. Detailed Implementation

[0019] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0020] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0021] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0022] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] Example 1: Device Structure like Figure 1 and Figure 2 As shown, the carbon emission detection device for post-mine belt conveyor of the present invention includes a test chamber 1, and the two ends of the test chamber 1 are respectively connected to a coal sample replenishment chamber 2 and a coal sample extraction pipe 3.

[0024] Both the test chamber 1 and the coal sample supply chamber 2 are equipped with spiral conveyor devices 4. Specifically, one spiral conveyor device 4 is installed in the coal sample supply chamber 2; two spiral conveyor devices 4 are arranged side by side in the test chamber 1, located on either side of the spiral conveyor device 4 in the coal sample supply chamber 2, as shown below. Figure 2 As shown.

[0025] A gas concentration sensor 5 is installed inside the test chamber 1. There are four gas concentration sensors 5, located at the four corners of the test chamber 1, at a height equal to the midpoint between the coal sample height and the top of the test chamber 1. Both the test chamber 1 and the coal sample replenishment chamber 2 are cuboid structures with dimensions of 0.8m × 0.5m × 0.3m and 0.4m × 0.5m × 0.3m, respectively. The spiral diameter of the spiral conveyor 4 is 0.1m. The lower end of the spiral conveyor 4 is 0.01m from the bottom of the test chamber 1 or the coal sample supply chamber 2 to ensure a safe distance. The upper end of the spiral conveyor 4 is 0.01~0.05m from the top of the flattened coal seam to ensure that the coal sample can completely cover the spiral conveyor 4 without affecting the flatness of the top. The filling height of the coal sample in the test chamber 1 is 0.25m, which is the height from the top of the coal seam to the bottom of the chamber after stacking, with a 0.05m space reserved to prevent coal sample overflow.

[0026] The core working principle of this embodiment is as follows: the coal sample extraction tube 3 is used to continuously and uniformly extract the residual coal sample after the test from the test chamber 1. It works in conjunction with the feeding speed of the spiral conveyor device 4 in the coal sample replenishment chamber 2 to maintain the total mass and shape of the coal sample in the test chamber 1, so as to avoid the distortion of gas concentration measurement due to changes in coal sample mass.

[0027] Example 2: Detection Method A detection method using the carbon emission detection device for post-mine belt conveyor transport described in Example 1 includes the following steps: (A) Determine the gas content Q value per kg of coal; First, drill horizontally 0.5m into the coal face to a depth of 0.5m (ensuring the coal gas remains in situ). Take 10 samples from the mining area at 3-5m intervals, seal and wrap each sample, with each sample weighing 1kg. Crush the 1kg samples into granules, ensuring that over 97% of the pulverized coal samples have a particle size greater than 0.20mm. After drying at 40℃ under normal temperature and pressure for 3 hours, determine the gas content of each sample in the laboratory. Analyze the data using box plots, remove outliers, and calculate the average of the remaining data, which is taken as the gas content Q per kg of coal.

[0028] (B) Preparation of standard coal samples; Take 100 kg of coal sample from a depth of 0.5 m into the coal face. After crushing, over 97% of the coal sample should have a particle size greater than 0.20 mm. Dry the sample at 40℃ under normal temperature and pressure for 3 hours to completely release its methane content. Then, inject the required methane into the coal sample using a gas supply system. This system includes a gas cylinder, pressure regulator, pipeline, and flow control device. Slowly inject the required methane into the sealed container containing the coal sample, ensuring the injection rate is controlled at 60-80 ml / min and the injection pressure is controlled below 0.8 atm. Once the methane is injected into the coal sample, maintain stable experimental conditions for at least 12 hours to ensure the coal sample and methane reach equilibrium and that the methane adsorption in the coal is uniform.

[0029] Take 1 kg of the prepared coal sample each time and test its gas content in the laboratory, for a total of three tests. If the gas content per kg of coal sample is greater than Q in each of the three consecutive tests, it is considered qualified. Take 90 kg of the remaining coal sample and use it as the original material for the experiment. If the gas content per kg of coal sample is still not greater than Q in each of the three consecutive tests after 7 tests, start this step again.

[0030] (C) Dynamic monitoring and relationship function establishment; Take 60 kg of the processed coal sample and put it into test chamber 1. Put the remaining 30 kg into coal sample replenishment chamber 2, ensuring that the chamber is basically flat.

[0031] The spiral conveyor 4 rotates at a constant speed, ensuring that exactly 1 kg of coal sample is transported out every 2 minutes. The coal sample extraction tube 3, in conjunction with the coal sample replenishment chamber 2, replenishes the test chamber 1 with the corresponding mass of coal sample taken out, ensuring that the total mass and basic shape of the sample remain unchanged, thus avoiding distortion of gas concentration measurements due to changes in coal sample mass.

[0032] Four gas concentration sensors 5 are located at the four corners of the test chamber 1, with their height between the coal sample height and the top of the test chamber 1.

[0033] ① Relationship function one (the relationship between gas concentration C and time t); The average value of the gas concentration data from four gas concentration sensors 5 is calculated to obtain the relationship between the gas concentration C monitored at a fixed point and time t under a 60-minute test, i.e., relationship function one: ; Where: C is the gas concentration monitored at fixed points, in cm³ / g; a1 is the gas diffusion correction coefficient of the coal sample, with a value of 1.3185; 60Q is the total gas content of the coal body, in cm³; b represents the temperature correction coefficient, with specific values ​​referred to Table 1; t is the time for normal gas escape, in min; m1 is the compensation coefficient for the degree of coal sample pulverization, with specific values ​​referred to Table 2.

[0034] Table 1. Values ​​of temperature correction factor b

[0035] Linear interpolation formula: .

[0036] Table 2. Values ​​of the compensation coefficient m1 for the degree of coal pulverization.

[0037] Linear interpolation formula: .

[0038] ② Relationship Function Two (Relationship between residual gas content D inside a 1kg coal sample and time t). The experiment involved taking 1 kg of coal samples every 2 minutes, measuring the gas content of each sample, and recording the results in a table. After taking 30 sets of coal samples (60 minutes), the experiment was stopped, and the data was recorded. Based on the 30 sets of data, a smooth curve was plotted to derive the relationship between the residual gas content D in 1 kg of coal sample and time t, i.e., relationship function two. ; Where: D represents the residual gas content inside 1kg coal sample, in cm³; a2 is the gas content correction coefficient of coal sample, with a value of 2.0232; m2 is the coal sample structure correction coefficient, with a value of 0.2637; t is the time for normal gas escape, in min.

[0039] ③ Establish the correlation function between sensor measurement points and the overall coal sample content; Both relational functions one and two change with time. By taking time t as the independent variable, we obtain relational function three between the average gas concentration at the five measuring points of the gas concentration sensor and the overall gas content of the coal sample: ; Where: D represents the residual gas content inside 1 kg of coal sample, in cm³; K represents the total gas content in the coal body, i.e., 60Q, in cm³; b represents the temperature correction coefficient, the specific value of which is shown in Table 1; e is the natural logarithm, with a value of 2.718; r represents the coal dryness correction coefficient, with a value of 0.2; C is the gas concentration monitored at fixed points, in cm³ / g; and m represents the coal pulverization correction coefficient, with a value of 10.

[0040] (D) Determine the gas escape rate δ; Based on the total gas content of the coal body (60Q) and the residual gas content (D) inside a 1kg coal sample, the gas escape amount (δ) is calculated: δ=60Q 60D; Where: 60Q is the total gas content of the coal body, in cm³; D represents the residual gas content inside 1kg coal sample, in cm³; 60D is the total residual gas content of 60kg coal sample, in cm³.

[0041] Example 3: Specific Calculation Example The specific calculation process using the detection method described in Example 2 is as follows: Step 1: Determine the Q value.

[0042] At a depth of 0.5 m horizontally inward from the coal wall of the working face, 10 groups of mine samples are taken at intervals of 3 - 5 m, sealed and wrapped, with each group weighing 1 kg. The obtained samples are crushed into granular form, with more than 97% of the particle size of the crushed coal sample above 0.20 mm, and dried at normal temperature and pressure for 3 h at 40 °C. The gas content of each group is determined in the laboratory, and the gas content per kg of coal body is calculated as Q, with the unit of cm³.

[0043] Step 2: Prepare standard coal samples.

[0044] Another 100 kg of coal samples are taken at a depth of 0.5 m horizontally inward from the coal wall of the working face. The coal samples are crushed into granular form, with more than 97% of the particle size of the crushed coal sample above 0.20 mm, and dried at normal temperature and pressure for 3 h at 40 °C to completely release their gas content, and then gas is injected to prepare the coal samples. Take 1 kg of the prepared coal samples, determine their gas content in the laboratory, and conduct the experiment three times. When the gas content per kg in the obtained coal samples is greater than Q, it is qualified. Take out 90 kg from all the coal samples and use it as the experimental raw material.

[0045] Step 3: Conduct dynamic monitoring experiments.

[0046] Put the coal samples into the experimental device described in Example 1 to start the experiment. Take out 1 kg of coal samples every 2 min, measure the gas content of the coal samples, record it in the table. After continuously taking out 30 groups of coal samples, that is, after 60 min, stop the experiment and record the data. Obtain the relationship between the gas concentration C and time t of fixed-point monitoring under the condition of testing for 60 minutes; according to the 30 groups of data, draw a smooth curve to obtain the relationship between the residual gas content D inside 1 kg of coal samples and time t.

[0047] Step 4: Determine the specific form of the relationship function.

[0048] According to the experimental data fitting, obtain the specific numerical expressions of relationship function one and relationship function two: ; ; Step 5: Establish the associated relationship function.

[0049] Through relationship function one and relationship function two, obtain the relationship function between the average gas concentration at the 5 measuring points of the gas concentration sensor and the gas content of the overall coal samples: ; Step 6: Calculate the gas escape amount.

[0050] By measuring the gas concentration difference between gas concentration sensors 5 at both ends of the coal seam in the next process, the change in gas content within the coal seam can be calculated, i.e., the gas escape amount δ for this process. When t=60min, D≈0.687cm³, and based on this escape amount δ, the gas emission amount for this process can be calculated. twenty two.

[0051] Based on the above formula, the amount of gas escape in this process can be calculated, thus enabling a scientific and accurate calculation of carbon emissions from post-mine belt conveyor transport.

[0052] The above detailed description is a specific description of one of the feasible embodiments of the present invention. This embodiment is not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included within the scope of the technical solution of the present invention.

[0053] It should be particularly noted that the various embodiments listed in this specification and accompanying drawings are intended to illustrate the technical solutions and advantages of the present invention, and not to limit the scope of protection of the present invention. Without departing from the core ideas and technical effects of the present invention, those skilled in the art can make any form of improvement, substitution, combination, or modification to the structural arrangement, process parameters, material selection, control logic, etc., of the described embodiments; any obvious changes based on the same concept should be considered equivalent solutions of the present invention and should be included within the scope of protection defined by the claims of the present invention. The actual scope of protection of the present invention is determined by the appended claims and should be correctly understood in conjunction with the specification and accompanying drawings.

Claims

1. A carbon emission detection device for conveyor belts in mines, characterized in that: It includes a test chamber (1), one end of which is connected to a coal sample supply chamber (2) and the other end is connected to a coal sample extraction pipe (3); a spiral conveying device (4) is installed in both the test chamber (1) and the coal sample supply chamber (2); a gas concentration sensor (5) is installed inside the test chamber (1).

2. The carbon emission detection device for post-mine belt conveyor as described in claim 1, characterized in that: A spiral conveyor device (4) is provided in the coal sample supply bin (2); two spiral conveyor devices (4) are arranged side by side in the test bin (1), located on both sides of the spiral conveyor device (4) in the coal sample supply bin (2).

3. The carbon emission detection device for post-mine belt conveyor as described in claim 2, characterized in that: The number of gas concentration sensors (5) is 4, which are respectively set at the four corners of the test chamber (1) at the midpoint between the upper surface of the coal sample and the top of the test chamber (1).

4. The carbon emission detection device for post-mine belt conveyor as described in claim 3, characterized in that: The test chamber (1) and the coal sample supply chamber (2) are rectangular parallelepiped structures.

5. A detection method using the carbon emission detection device for post-mine belt conveyor transport as described in any one of claims 1 to 4, characterized in that, Includes the following steps: (A) First, drill horizontally into the underground working face to a depth of 0.5m. Take 10 samples from the mining area at intervals of 3-5m. Seal and wrap each sample, with a weight of 1kg. After crushing, determine the gas content of each sample in the laboratory. Use box plot analysis to obtain the gas content per kg of coal, which is denoted as Q. (B) Take 100 kg of coal sample from a depth of 0.5 m in the underground working face, crush it to completely release its gas content, and then inject the required gas into the coal sample through the gas supply system. The injection amount is controlled to ensure that the coal sample and gas reach a balance. Take 1 kg of the prepared coal sample each time and test its gas content in the laboratory. Test it three times in total. If the gas content per kg of coal sample is greater than Q in each of the three consecutive tests, it is considered qualified. Take 90 kg of the remaining coal sample and use it as the original material for the experiment. If the gas content per kg of coal sample is not greater than Q in each of the seven tests, start this step again. (C) The carbon emission detection device of the post-mine belt conveyor is used for detection: 60 kg of the processed coal sample is put into the test chamber (1), and the remaining 30 kg is put into the coal sample replenishment chamber (2) to ensure that the chamber is basically flat; the spiral conveyor (4) rotates at a constant speed to ensure that 1 kg of coal sample is transported out every 2 minutes. The coal sample replenishment chamber (2) replenishes the corresponding mass of coal sample into the test chamber (1) according to the mass of coal sample taken out of the test chamber (1) and monitors the gas content inside the test chamber (1); the relationship between gas concentration C and time t and the relationship between the residual gas content D inside 1 kg of coal sample and time t are obtained; the relationship function between the average gas concentration at the gas concentration sensor (5) and the overall coal sample gas content is obtained by taking time t as the independent variable; and then the gas escape amount δ is calculated.

6. The detection method according to claim 5, characterized in that: In step (A), the obtained 1kg sample is crushed into granules. More than 97% of the crushed coal sample has a particle size of more than 0.20mm. After drying at 40℃ and normal pressure for 3 hours, the gas content of each group is calculated, and the data is analyzed using a box plot.

7. The detection method according to claim 6, characterized in that: In step (B), more than 97% of the pulverized coal sample has a particle size greater than 0.20 mm. It is dried at 40°C under normal temperature and pressure for 3 hours, and then its gas content is completely released. The gas supply system includes a gas cylinder, a pressure regulator, pipelines and flow control equipment. The required gas is slowly injected into the sealed container containing the coal sample, ensuring that the gas injection rate is controlled at 60~80 ml / min and the injection pressure is controlled within 0.8 atm. The experimental conditions are kept stable, and the injection process lasts for more than 12 hours to ensure that the coal sample and gas reach a state of equilibrium.

8. The detection method according to claim 7, characterized in that: In step (C), the average value of the gas concentration data from the four gas concentration sensors (5) is calculated to obtain the relationship between the gas concentration C monitored at the fixed point and time t under the test for 60 minutes, i.e., relationship function one: ； Where C is the methane concentration monitored at a fixed point, in cm³ / g; a1 is the methane diffusion correction coefficient for the coal sample, with a value of 1.3185; 60Q is the total methane content in the coal body, in cm³; b is the temperature correction coefficient, which is determined as follows: when T < 5℃, b = 1; when 5℃ ≤ T < 25℃, b = 1 + (T - 5) / 4; when T ≥ 25℃, b = 7; t is the time for normal methane escape, in min; m1 is the compensation coefficient for the degree of coal sample pulverization, which is determined as follows: when the pulverized particle size d < 0.10mm, m1 = 4; when 0.10mm ≤ d < 0.40mm, m1 = 4 - (d - 0.10) / 0.10; when d ≥ 0.40mm, m1 = 1. The experiment involved taking 1 kg of coal samples every 2 minutes and measuring the gas content of each sample. After taking 30 sets of coal samples, the experiment was stopped. A smooth curve was plotted based on the 30 sets of data to obtain the relationship between the residual gas content D in 1 kg of coal sample and time t, i.e., relationship function two: ； Where D represents the residual gas content inside 1 kg of coal sample, in cm³; a2 is the gas content correction coefficient of coal sample, with a value of 2.0232; m2 is the coal sample structure correction coefficient, with a value of 0.2637; and t is the time for normal gas escape, in min.

9. The detection method according to claim 8, characterized in that: In step (C), relational function one and relational function two are correlated with time t as the independent variable to obtain relational function three between the average gas concentration at the gas concentration sensor (5) measuring point and the overall coal sample gas content: ； Where D represents the residual gas content inside 1 kg of coal sample, in cm³; K represents the total gas content of the coal body, i.e., 60Q, in cm³; b is the temperature correction coefficient, which is determined as follows: when T < 5℃, b = 1; when 5℃ ≤ T < 25℃, b = 1 + (T - 5) / 4; when T ≥ 25℃, b = 7; e is the base of the natural logarithm, with a value of 2.718; r is the coal dryness correction coefficient, with a value of 0.2; C is the gas concentration monitored at fixed points, in cm³ / g; and m is the coal pulverization correction coefficient, with a value of 10.

10. The detection method according to claim 9, characterized in that: In step (C), based on the total gas content of the coal body (60Q) and the residual gas content (D) inside 1 kg of coal sample, the gas escape amount (δ) is calculated: ； Wherein, 60Q is the total gas content of the coal body, in cm³; D is the residual gas content inside 1kg coal sample, in cm³; and 60D is the total residual gas content of 60kg coal sample, in cm³.

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