Coal seam gas desorption amount measuring device and measuring method

Abstract

The invention belongs to the field of coal mine underground gas parameter measurement, and relates to a coal seam gas desorption amount measurement device and method. The measuring device comprises a tank body and a tank cover detachably mounted on the tank body, a containing cavity is formed in the can cover, and the integrated circuit board is arranged in the containing cavity; a pressure sensor and a temperature sensor facing the interior of the tank body are arranged on the bottom surface of the tank cover and are electrically connected with the integrated circuit board; and a Bluetooth communication module is arranged on the integrated circuit board. A lithium battery is further arranged in the containing cavity and electrically connected with the integrated circuit board. A display screen is arranged on the top face of the tank cover and electrically connected with the integrated circuit board. According to the coal seam gas desorption amount measuring device, the coal sample gas desorption amount is calculated through the pressure data and the temperature data, long-time manual reading needed by a measuring cylinder drainage and gas collection method in an underground coal mine is avoided, and the measuring efficiency of the coal sample gas desorption amount is improved.

Description

Technical Field

[0001] The invention belongs to the field of underground coal mine gas parameter measurement, and relates to a coal seam gas desorption amount measurement device and a measurement method. Background Art

[0002] As one of the most basic gas parameters of coal seams, the accurate measurement of gas content is of vital importance for in-depth research on the distribution law of coal seam gas, accurate prediction of mine gas outburst volume, effective evaluation of gas extraction effect, and scientific prediction and prevention of coal and gas outbursts.

[0003] The traditional method for determining gas content (normal pressure natural desorption method) divides the gas content into three parts: normal pressure gas desorption (including natural desorption of coal samples and crushing desorption), normal pressure non-desorption, and gas loss during sampling. The normal pressure gas desorption is obtained by direct measurement, while the gas loss is calculated based on the exposure time of the coal sample during the sampling process and the law of normal pressure natural desorption in the well after sampling. By accurately measuring the desorption of coal samples and combining the measurement and calculation of other relevant parameters, the gas content of the coal seam can be directly obtained. It can be seen that obtaining the gas desorption of coal samples is the basis and prerequisite for calculating the gas content of coal seams.

[0004] The traditional gas content determination process is usually divided into two stages: underground in the coal mine and in the ground laboratory. Both stages rely on the cylinder drainage gas collection method. Specifically, the atmospheric pressure gas desorption of the coal sample is measured underground in the coal mine, and the atmospheric pressure desorption of the coal sample before and after crushing is measured in the ground laboratory. The desorption law is derived from the atmospheric pressure desorption data of the underground coal mine to further calculate the gas loss in the underground sampling process. The atmospheric pressure non-desorbable amount is calculated based on the a and b adsorption constants of the coal and laboratory data such as industrial analysis, and finally the total gas content of the coal seam is obtained.

[0005] In the underground measurement stage of coal mines, according to relevant standards, the underground measurement requires continuous observation of the measuring tube reading for 60 to 120 minutes, or until the desorption volume drops to less than 2 cm 3 / min. This process requires manual reading and recording. However, when measuring underground, due to factors such as insufficient ambient light and dust interference, manual reading is prone to errors, affecting the accuracy of the data. This measurement method significantly reduces the efficiency of measuring the gas content of a single coal sample and increases the waiting time of the measurement personnel underground, which may affect the overall work progress and personnel safety. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a coal seam gas desorption amount measuring device and method, which calculates the coal sample gas desorption amount through pressure data and temperature data, avoids the long time manual reading required by the measuring cylinder drainage gas collection method in the coal mine, improves the measurement efficiency of the coal sample gas desorption amount, and further improves the measurement efficiency of the coal sample gas content.

[0007] To achieve the above-mentioned purpose, the present invention provides a coal bed gas desorption amount measuring device, which includes a tank body and a tank cover detachably mounted on the tank body; the tank cover has a containing cavity, and an integrated circuit board is arranged in the containing cavity; the bottom surface of the tank cover is provided with a pressure sensor and a temperature sensor facing the tank body, and the pressure sensor and the temperature sensor are electrically connected to the integrated circuit board; the integrated circuit board is provided with a Bluetooth communication module for wireless communication with a mobile terminal. The mobile terminal calculates the gas desorption amount of the coal sample through the measurement data of the pressure sensor and the temperature sensor.

[0008] Optionally, the accommodating cavity is eccentrically arranged in the tank cover, and the solid part of the tank cover is provided with an air passage connecting the interior of the tank body and the outside.

[0009] Optionally, the air passage includes two sections vertically connected to each other, the first section extends from the side of the tank cover to the inside of the tank cover, and the second section is perpendicular to the first section and extends into the tank body.

[0010] Optionally, an opening of the air passage on the side of the tank cover is provided with an air nozzle, and the air nozzle is connected to the air passage in a manner of being partially embedded in the tank cover.

[0011] Optionally, the solid part of the tank cover is provided with an embedded valve, which is inserted into the tank cover from the top surface of the tank cover and is arranged in the extension direction of the second section of the airway in a manner of connecting or blocking the two sections of the airway, and the end of the embedded valve extends out of the top surface of the tank cover.

[0012] Optionally, a lithium battery is also disposed in the accommodating cavity, and the lithium battery is electrically connected to the integrated circuit board.

[0013] Optionally, a display screen is provided on the top surface of the can cover, and the display screen is electrically connected to the integrated circuit board; a Type-c charging port is provided on the side of the can cover, and the Type-c charging port is electrically connected to the integrated circuit board.

[0014] Optionally, a charging port protection cover is provided outside the Type-c charging port.

[0015] Optionally, the tank body has a double-layer structure, a vacuum interlayer is formed between the inner layer and the outer layer, or a heat-insulating material is filled between the inner layer and the outer layer.

[0016] Optionally, at least one first connecting ear symmetrically distributed along the center of the can cover is provided on the bottom surface of the can cover, and a second connecting ear matching the first connecting ear is provided on the edge of the can body, and the first connecting ear and the second connecting ear are fixed by a clamp.

[0017] Optionally, a sealing member for isolating gas from entering or exiting is provided at the connection between the first connecting ear and the second connecting ear.

[0018] Optionally, an annular groove is provided on the bottom surface of the tank cover, and an O-ring is embedded in the annular groove; the annular groove is arranged adjacent to the first connecting ear, and one end of the second connecting ear is inserted into the annular groove.

[0019] The present invention provides a method for measuring the desorption amount of coal seam gas, which is applied to the above-mentioned device for measuring the desorption amount of coal seam gas, and comprises the following steps:

[0020] S1. Load the coal sample into the measuring device and seal the measuring device;

[0021] S2, transferring the measuring device to the ground, during which the desorption measurement is started;

[0022] S3, set the measurement time t1, collect the desorption pressure and temperature of the coal sample every minute, and the measuring device automatically shuts down after reaching t1;

[0023] S4. Using the ideal gas state equation PV = nRT, the desorption pressure and temperature per unit time in the period t1 are converted into the gas desorption amount per unit time Q t .

[0024] Furthermore, in step S1, the exposure time t0 of the coal sample from the start of drilling to the completion of loading and sealing is recorded to calculate the gas loss within the exposure time t0.

[0025] The beneficial effects of the present invention are:

[0026] The coal seam gas desorption amount measuring device proposed by the present invention integrates the coal sample storage container and the desorption amount measuring function, and is particularly suitable for the measurement of coal sample gas desorption in coal mines. When in use, the underground measuring personnel only need to cooperate with the explosion-proof mobile phone to input the coal sample information. After the fresh coal sample is loaded into the coal seam gas desorption amount measuring device and sealed, the underground coal sample gas desorption amount measurement process can be started. The measuring personnel do not need to wait for a long time underground, and the "load sample and go" is realized.

[0027] When the coal sample is transported to the ground laboratory, it can be paired with the coal seam gas desorption amount measuring device through an explosion-proof mobile phone to easily read the initial gas desorption data of the coal sample. In addition, the coal seam gas desorption amount measuring device also has the function of automatically measuring the temperature and pressure during the gas desorption process of the underground coal sample. By calculating these data through the mobile phone software model, the corresponding coal sample gas desorption amount can be obtained. In general, the coal seam gas desorption amount measuring device provided by the present invention will greatly improve the efficiency of coal seam gas content measurement and effectively reduce the labor intensity of the measurement personnel.

[0028] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0030] Figure 1 This is a schematic structural diagram of a device for measuring coal seam gas desorption amount provided by the present invention.

[0031] Reference numerals:

[0032] 1-tank cover, 1.1-accommodating cavity, 1.2-first connecting ear, 1.3-annular groove, 1.4-O-ring, 2-tank body, 2.1-second connecting ear, 3-clamp, 4-embedded valve, 5-air nozzle, 6-pressure sensor, 7-temperature sensor, 8-display screen, 9-integrated circuit board, 10-lithium battery, 11-Type-c charging port, 12-charging port protection cover, 13-air duct, 13.1-first section, 13.2-second section. DETAILED DESCRIPTION

[0033] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0034] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0035] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0036] Example 1

[0037] The present invention provides a coal seam gas desorption amount measuring device, which integrates the coal sample storage container and the desorption amount measuring function, and is particularly suitable for the measurement link of the coal sample gas desorption amount in coal mines. The coal seam gas desorption amount measuring device mainly includes a tank body 2 and a tank cover 1, and the tank cover 1 is detachably mounted on the tank body 2. A receiving cavity 1.1 is provided inside the tank cover 1, and an integrated circuit board 9 is arranged in the receiving cavity 1.1. A pressure sensor 6 and a temperature sensor 7 are arranged on the bottom surface of the tank cover 1 facing the tank body 2, and the two are electrically connected to the integrated circuit board 9 for real-time monitoring of the temperature and pressure changes during the coal sample gas desorption process. The integrated circuit board 9 is also equipped with a Bluetooth communication module to wirelessly communicate with a mobile terminal, and the mobile terminal calculates the gas desorption amount of the coal sample through the measurement data of the pressure sensor 6 and the temperature sensor 7. The mobile terminal is preferably a matching explosion-proof mobile phone, and the explosion-proof mobile phone establishes wireless communication with the integrated circuit board 9 to realize remote control of the measurement process and read the measurement data of the pressure sensor 6 and the temperature sensor 7, and further calculate the desorption amount of the coal sample through an embedded algorithm.

[0038] Furthermore, the accommodating cavity 1.1 is arranged eccentrically in the tank cover 1, and the solid part of the tank cover 1 is provided with an air passage 13 connecting the inside of the tank body 2 and the outside. The air passage 13 is composed of two sections of channels that are vertically connected to each other, the first section 13.1 extends from the side of the tank cover 1 into the tank cover 1, and the second section 13.2 is perpendicular to the first section 13.1 and extends into the tank body 2. The air passage 13 is provided with a gas nozzle 5 at the opening of the side of the tank cover 1, and the gas nozzle 5 is connected to the air passage 13 in a manner of being partially embedded in the tank cover 1, so as to facilitate the discharge of gas in the tank. In addition, the solid part of the tank cover 1 is also provided with an embedded valve 4, which is inserted into the tank cover 1 from the top surface of the tank cover 1, and the embedded valve 4 is threadedly matched with the tank cover 1, so that the embedded valve 4 can move in the extension direction of the second section 13.2, thereby controlling the on-off of the air passage 13, thereby ensuring the sealing of the coal sample during the desorption process.

[0039] In order to improve the portability and practicality of the coal seam gas desorption measuring device, a lithium battery 10 is also placed in the accommodating cavity 1.1 to provide long-lasting power support for the integrated circuit board 9. A display screen 8 is provided on the top surface of the tank cover 1 for displaying coal sample information and working status. At the same time, a Type-c charging port 11 is also provided on the side of the tank cover 1 for convenient charging of the lithium battery 10. A charging port protective cover 12 is provided outside the Type-c charging port 11 to prevent dust and water, and to prevent physical damage and foreign objects from entering, provide safety protection, reduce the risk of electrostatic discharge and accidental touch, and keep the appearance of the device neat and beautiful, thereby improving the overall user experience.

[0040] In order to enhance the thermal insulation effect of the coal sample tank, the tank body 2 adopts a double-layer structure, forming a sandwich between the inner layer and the outer layer. The sandwich can be vacuumed or filled with thermal insulation material to reduce the impact of external temperature on the gas temperature measurement in the tank.

[0041] In terms of the connection between the can cover 1 and the can body 2, at least one first connection ear 1.2 symmetrically distributed along the center of the can cover 1 is provided on the bottom surface of the can cover 1, and a second connection ear 2.1 matching with the first connection ear 1.2 is provided on the edge of the can body 2. The first connection ear 1.2 and the second connection ear 2.1 are fixed by a clamp 3, so that the can cover 1 and the can body 2 are tightly connected. At the same time, a sealing member is also provided at the connection between the first connection ear 1.2 and the second connection ear 2.1 to isolate the gas from entering and exiting, and ensure the sealing inside the can body 2.

[0042] In some embodiments, the bottom surface of the tank cover 1 is further provided with an annular groove 1.3, in which an O-ring 1.4 is embedded. The annular groove 1.3 is arranged adjacent to the first connecting ear 1.2, and one end of the second connecting ear 2.1 is inserted into the annular groove 1.3. Such a design makes the sealing between the tank cover 1 and the tank body 2 more reliable.

[0043] In some embodiments, the top surface of the tank cover 1 is configured as a panel made of PC material.

[0044] Example 2

[0045] The present invention provides a method for measuring the desorption amount of coal seam gas, which is applied to the above-mentioned device for measuring the desorption amount of coal seam gas, and comprises the following steps:

[0046] S1. Load the coal sample into the measuring device and seal the measuring device;

[0047] Specifically, the underground measurement personnel turn on the coal seam gas desorption measurement device at the sampling site, and use the matching explosion-proof mobile phone for Bluetooth pairing. After entering the corresponding sampling information, it can enter the standby state. Subsequently, the embedded valve 4 is rotated outward to the maximum open state to allow the interior of the tank body 2 to communicate with the external environment. Open the clamp 3, separate the tank cover 1 and the tank body 2, and then quickly load the fresh coal sample drilled from the coal mine into the tank body 2 after screening it to a specific particle size (for example, 1-3mm), and immediately cover the tank cover 1 and seal it with the clamp 3. After recording various times on the explosion-proof mobile phone, tighten the embedded valve 4 to completely isolate the inside and outside of the tank body 2.

[0048] S2, transferring the measuring device to the ground, during which the desorption measurement is started;

[0049] Specifically, close the valve 4 and press the start desorption button on the explosion-proof mobile phone software at the same time. At this time, the coal seam gas desorption amount measuring device will automatically collect the desorption pressure and temperature of the coal sample every minute.

[0050] S3, set the measurement time t1, collect the desorption pressure and temperature of the coal sample every minute, and the measuring device automatically shuts down after reaching t1;

[0051] S4. Using the ideal gas state equation PV = nRT, the desorption pressure and temperature per unit time in the period t1 are converted into the gas desorption amount per unit time Q t .

[0052] Furthermore, in step S1, the exposure time t0 of the coal sample from the start of drilling to the completion of loading and sealing is recorded to calculate the gas loss within the exposure time t0.

[0053] When the coal seam gas desorption amount measuring device is transported to the ground laboratory, it only needs to be turned on and paired with the explosion-proof mobile phone via Bluetooth. According to the coal sample information input underground, the explosion-proof mobile phone will read the corresponding desorption pressure and temperature data. Through the algorithm model embedded in the mobile phone software, the coal sample gas desorption amount per minute can be obtained. This innovation not only greatly improves the efficiency of coal seam gas content determination, but also effectively reduces the labor intensity of the measurement personnel. In general, the coal seam gas desorption amount measuring device provided by the present invention realizes the combination of coal sample storage and desorption amount measurement, which brings great convenience and efficiency improvement to the measurement of coal sample gas desorption amount in coal mines.

[0054] Example 3

[0055] Based on the gas desorption amount determination method provided in Example 2 of the present invention, the present invention also provides a coal seam gas content determination method. Specifically, after step S4, the following steps are also included:

[0056] S5. Release: Unscrew the built-in valve 4 to connect the first section 13.1 and the second section 13.2 of the airway 13, and release the gas in the measuring device through the gas nozzle 5 until the pressure in the device is balanced with the external atmospheric pressure. During the process, the volume of the discharged gas is measured by a flow meter or a drainage gas collection method, and the final volume data Q1 is recorded with an explosion-proof mobile phone;

[0057] S6. After the gas in the device is released, take out the coal sample and crush it with a special laboratory crusher until more than 95% of the coal sample particle size is less than 0.25mm. During the crushing process, the gas desorption volume of the coal sample is measured by a flow meter or drainage gas collection method, and the final volume data Q2 is recorded with an explosion-proof mobile phone;

[0058] S7. Use an explosion-proof mobile phone to record the ambient temperature and pressure of the ground laboratory to convert Q1 and Q2 into Q′1 and Q′2 under standard working conditions;

[0059] S8. Calculate the gas loss during the exposure time t0;

[0060] Specifically, the ideal gas state equation PV = nRT is used to convert the desorption pressure and temperature per unit time in the period t1 into the gas desorption amount per unit time, and Q t =a(t-t0) i +Q 损失 The desorption data in all t1 periods are fitted, where a is the fitting coefficient, i is the particle size characteristic value of the fixed particle size coal sample, and the fitting Q is obtained through experimental investigation. 损失 The gas loss Q′ can be obtained by converting under standard working conditions. 损失 ;

[0061] S9. Calculate the amount of non-desorbable at normal pressure Q c ;

[0062] Specifically, the Langmuir formula is used to combine the adsorption constants a and b of coal and the industrial analysis of Q c Perform calculations.

[0063]

[0064] In the formula, a and b are the adsorption constants of coal, A ad is the ash content of the coal sample, M ad is the moisture content of the coal sample, F is the porosity of the coal sample, and ARD is the apparent density of the coal sample.

[0065] S10. Calculate the total gas content of the coal sample:

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A device for measuring coal bed gas desorption, characterized in that: The coal seam gas desorption amount measuring device comprises a tank body (2) and a tank cover (1) detachably mounted on the tank body (2); the tank cover (1) has a receiving cavity (1.1) in it, and an integrated circuit board (9) is arranged in the receiving cavity (1.1); the bottom surface of the tank cover (1) is provided with a pressure sensor (6) and a temperature sensor (7) facing the tank body (2), and the pressure sensor (6) and the temperature sensor (7) are electrically connected to the integrated circuit board (9); a Bluetooth communication module is provided on the integrated circuit board (9) for wireless communication with a mobile terminal; the mobile terminal calculates the gas desorption amount of the coal sample through the measurement data of the pressure sensor (6) and the temperature sensor (7).

2. The coal bed gas desorption amount measuring device according to claim 1, characterized in that: The accommodating cavity (1.1) is arranged eccentrically in the tank cover (1), and the solid part of the tank cover (1) is provided with an air passage (13) connecting the interior of the tank body (2) and the outside.

3. The coal bed gas desorption amount measuring device according to claim 2, characterized in that: The air passage (13) comprises two sections which are vertically connected to each other, wherein the first section (13.1) extends from the side of the tank cover (1) into the tank cover (1), and the second section (13.2) is perpendicular to the first section (13.1) and extends into the tank body (2).

4. The coal bed gas desorption amount measuring device according to claim 2, characterized in that: The opening of the air passage (13) located on the side of the tank cover (1) is provided with an air nozzle (5), and the air nozzle (5) is communicated with the air passage (13) in a manner of being partially embedded in the tank cover (1).

5. The coal bed gas desorption amount measuring device according to claim 3 is characterized in that: The solid part of the tank cover (1) is provided with an embedded valve (4), which is inserted into the tank cover (1) from the top surface of the tank cover (1) and is arranged in the extension direction of the second section (13.2) of the air channel (13) in a manner of connecting or blocking the two sections of the air channel (13), and the end of the embedded valve (4) protrudes from the top surface of the tank cover (1).

6. The coal bed gas desorption amount measuring device according to claim 1, characterized in that: A lithium battery (10) is also arranged in the accommodating cavity (1.1), and the lithium battery (10) is electrically connected to the integrated circuit board (9).

7. The coal bed gas desorption amount measuring device according to claim 1, characterized in that: The top surface of the can cover (1) is provided with a display screen (8), and the display screen (8) is electrically connected to the integrated circuit board (9); the side surface of the can cover (1) is provided with a Type-C charging port (11), and the Type-C charging port (11) is electrically connected to the integrated circuit board (9).

8. The coal bed gas desorption amount measuring device according to claim 1, characterized in that: The bottom surface of the can cover (1) is provided with at least one first connecting ear (1.2) symmetrically distributed along the center of the can cover (1), and the edge of the can body (2) is provided with a second connecting ear (2.1) matching with the first connecting ear (1.2), and the first connecting ear (1.2) and the second connecting ear (2.1) are fixed by a clamp (3).

9. A method for measuring coal bed gas desorption, applied to the coal bed gas desorption measuring device according to any of the preceding claims, characterized in that: The following steps are involved: S1. Loading the coal sample into the measuring device and sealing the measuring device; S2, transferring the measuring device to the ground, and starting desorption measurement during this process; S3, set the measurement time t1, collect the desorption pressure and temperature of the coal sample every minute, and the measuring device automatically shuts down after reaching t1; S4. Using the ideal gas state equation PV = nRT, the desorption pressure and temperature per unit time in the period t1 are converted into the gas desorption amount per unit time Q t .

10. The determination method according to claim 9, characterized in that: In step S1, the exposure time t0 of the coal sample from the start of drilling to the completion of loading and sealing is recorded to calculate the gas loss within the exposure time t0.

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