Carbon dioxide cyclic capture fire extinguishing device and automatic fire extinguishing method for coal mine goaf

Abstract

The invention discloses a carbon dioxide cyclic trapping fire extinguishing device which comprises a plurality of fire extinguishing assemblies, each fire extinguishing assembly comprises a waterproof breathable film wrapped with a solid amine sealing material, the waterproof breathable film is arranged on a temperature sensor, and the temperature sensor is arranged on a gas taking beam tube of an automatic detection system. A resistance wire with a heating function is arranged in the solid amine sealing material, a control unit is arranged on the temperature sensor, the control unit is electrically connected with the resistance wire and the temperature sensor, and an information transmission function and an information receiving function can be realized between each control unit and a control center of the automatic detection system. The invention further discloses an automatic fire extinguishing method for the coal mine goaf. The solid amine sealing material is used in a coal mine, and automatic fire extinguishing of the goaf of the coal mine is realized by utilizing the functions of automatic adsorption and carbon dioxide release of the solid amine sealing material.

Description

Technical Field

[0001] The present invention belongs to the technical field of mine fire prevention and extinguishing, and in particular relates to a carbon dioxide circulation capture fire extinguishing device and an automatic fire extinguishing method for a coal mine goaf. Background Art

[0002] my country's coal seams are complex and diverse in their occurrence conditions and geological structures, leading to frequent disasters and accidents. Fires caused by spontaneous coal combustion are particularly prominent. Mine fires are a major threat to production safety and cause significant losses in coal mines. Solid-state amine adsorbents are gaining popularity in the field of CO2 capture because they can improve the performance of solid-state amine materials by modifying the material matrix and the type of grafted amine functional groups, thereby enhancing CO2 capture efficiency. However, in the field of coal mine fire prevention and control, the application of temperature-sensitive materials for plugging leaks in coal mine goafs has yet to be seen. Summary of the Invention

[0003] The present invention proposes a carbon dioxide circulation capture fire extinguishing device, which enables solid amine materials to be used in coal mine goafs, thereby realizing automatic fire extinguishing in coal mine goafs.

[0004] To this end, the technical solution adopted by the present invention is: a carbon dioxide circulation capture fire extinguishing device, comprising several fire extinguishing components, each fire extinguishing component comprising a water-proof and breathable membrane wrapped with a solid amine sealing material, the water-proof and breathable membrane being arranged on a temperature sensor, the temperature sensor being arranged on an air intake bundle tube of an automatic detection system, a resistance wire with a heating function being arranged in the solid amine sealing material, a control unit being arranged on the temperature sensor, the control unit being electrically connected to the resistance wire and the temperature sensor, and each control unit being able to realize information transmission and information receiving functions with the control center of the automatic detection system.

[0005] As a preferred embodiment of the above scheme, the fire extinguishing assembly further includes a protective shell, which is arranged outside the water-proof and breathable membrane, the temperature sensor and the control unit, and is provided with a plurality of first through holes for gas to pass through.

[0006] More preferably, a hard protective cover is provided on the outer surface of each gas extraction bundle tube, the hard protective cover is provided with a plurality of second through holes for gas to pass through, and each fire extinguishing assembly is provided in the hard protective cover.

[0007] Further preferably, the temperature sensor is an optical fiber temperature sensor.

[0008] Also disclosed is a method for automatically extinguishing fire in a coal mine goaf, comprising the following steps:

[0009] S1: Installation of the device: evenly arrange the above-mentioned fire extinguishing components at a certain distance on the gas extraction bundle pipe arranged by the automatic detection system in the goaf;

[0010] S2: Automatic fire extinguishing. When the automatic detection system fails to detect the concentration of combustible gas in the goaf, the coal will undergo oxidation reaction and begin to heat up spontaneously. When the temperature reaches T0, the solid amine sealing material in the fire extinguishing component will desorb and release carbon dioxide, inerting the goaf environment and suppressing the spontaneous combustion of the coal. When the coal in the goaf loses its spontaneous combustion hazard and drops to room temperature, the solid amine material will absorb and store the carbon dioxide in the goaf.

[0011] When the automatic detection system detects combustible gas in the goaf, the solid amine sealing material in the corresponding area is heated through the resistance wire according to the temperature detected by the temperature sensor and the concentration of the combustible gas, so that the solid amine sealing material automatically releases a certain amount of carbon dioxide, thereby extinguishing the fire. After the fire is extinguished, the heating of the solid amine sealing material is stopped, and the solid amine material is cooled to absorb carbon dioxide for storage. The amount of carbon dioxide released is calculated according to the following formula:

[0012]

[0013] in, is the amount of carbon dioxide released, in units of , is the air leakage compensation coefficient, which is adjusted according to the complexity of the air leakage path. is the air leakage in the goaf, in units of , is the amount of coal left in the goaf, in tons. is the residual coal coverage factor, in units of , adjusted according to the tendency of coal spontaneous combustion, is the action time, the unit is , It is the risk level of spontaneous combustion of coal, which is divided into levels according to the volatile matter of coal. It is the environmental risk level, which is divided into levels according to the detected gas concentration and temperature data.

[0014] More preferably, the value range of the air leakage compensation coefficient is 0.5-1.2, and the higher the value, the more complex the air leakage path.

[0015] Further preferably, the residual coal coverage coefficient is in the range of 0.1-0.3, and the higher the spontaneous combustion tendency of the coal, the higher the value.

[0016] Further preferably, the spontaneous combustion risk level of coal ranges from 1.0 to 1.5, and the higher the volatile matter of the coal, the higher the value. Usually, when the volatile matter of the coal is less than 15%, that is, When <15%, is 1.0, when 15%≤ <25%, is 1.2, when When ≥25%, is 1.5.

[0017] Further preferably, when the temperature is detected to be lower than T0 and the combustible gas concentration is lower than the warning value, it is a low risk. When the temperature is between T0 and T1, or the concentration of combustible gas is between the warning value and the critical value, it is a medium risk. When the temperature is higher than T1 or the concentration of combustible gas is higher than the critical value, it is a high risk. is 1.8.

[0018] Beneficial effects of the present invention:

[0019] 1) The solid amine sealing material with the function of cyclically capturing carbon dioxide is used in underground fire prevention and extinguishing. The conditions for absorbing and releasing carbon dioxide are simple and are only affected by temperature. When the temperature is reached, it can automatically release carbon dioxide, making the overall response timely.

[0020] 2) Solid amine sealing materials are distributed in the goaf. At the same time, according to the ambient temperature and gas concentration, the solid amine sealing materials in the corresponding area are heated to automatically release carbon dioxide to extinguish the fire, thereby effectively achieving the targeted release of carbon dioxide in the coal mine goaf, and then achieving efficient and timely control of coal mine goaf fires. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of the fire extinguishing assembly in the present invention.

[0022] Figure 2 This is an installation diagram of the fire extinguishing assembly when a hard protective cover is used in the present invention.

[0023] Figure 3 This is a schematic diagram of the fire extinguishing assembly of the present invention being laid in the goaf.

[0024] Figure numerals: fire extinguishing component-10, solid amine sealing material-11, water-proof and breathable membrane-12, temperature sensor-13, air extraction bundle tube-20, hard protective cover-30. DETAILED DESCRIPTION

[0025] The present invention will be further described below by way of examples and in conjunction with the accompanying drawings:

[0026] like Figure 1-3As shown, a carbon dioxide circulation capture fire extinguishing device is mainly composed of a number of fire extinguishing components 10, each of which includes a water-proof breathable membrane 12 wrapped with a solid amine sealing material 11, the water-proof breathable membrane 12 is arranged on a temperature sensor 13, and the temperature sensor 13 is arranged on an air extraction bundle pipe 20 of an automatic detection system. A resistance wire with a heating function is arranged in the solid amine sealing material 11 (not shown in the figure), and a control unit is arranged on the temperature sensor 13, and the control unit is electrically connected to the resistance wire and the temperature sensor 13, and each control unit can realize information transmission function and information receiving function with the control center of the automatic detection system.

[0027] The automatic detection system, deployed within a mine to monitor gases such as CO, is a conventional system. The gas bundle tube is a component of the automatic detection system. The water-proof, breathable membrane is primarily used to isolate moisture while allowing carbon dioxide to pass through. Due to its adhesive properties, it can be bonded to the temperature sensor. The control unit, which utilizes an MCU, primarily transmits the temperature signal detected by the corresponding temperature sensor to the control center. By receiving signals from the control center requesting the resistor wire to operate, it controls the resistor wire's operation, thereby heating the solid-state amine sealing material.

[0028] The production process of the solid amine sealing material is as follows: solid waste materials such as coal gangue generated during coal mining and fly ash from coal-fired power plants are crushed and screened. Then, water glass is used as an alkaline activator to activate the coal gangue and fly ash. A foaming agent is added, uniformly stirred, and poured into a mold. Finally, amino groups are grafted onto the solid waste-based porous particles through a grafting method to prepare the solid amine sealing material. A resistance wire is embedded in the mold during casting, thus creating a built-in resistance wire within the solid amine sealing material. Of course, the solid amine sealing material can also be made from other ingredients.

[0029] To prevent overburden from collapsing and damaging the equipment, the fire extinguishing assembly 10 also includes a protective housing. This housing covers the waterproof and breathable membrane 12, temperature sensor 13, and control unit. The housing is provided with a number of primary through-holes for gas passage. Each fire extinguishing assembly is provided with a separate protective housing. Alternatively, each air extraction bundle can be provided with a hard protective cover 30, each with a number of secondary through-holes for gas passage. Each fire extinguishing assembly is housed within the hard protective cover. In this case, fire extinguishing assemblies on the same air extraction bundle share a single hard protective cover, which can be made of stainless steel tubing.

[0030] Preferably, the temperature sensor 13 is an optical fiber temperature sensor, which has a wide temperature detection range and high resolution. In this application, optical fiber is used to transmit signals, and each control unit is equipped with a separate power supply.

[0031] A method for automatically extinguishing fire in a coal mine goaf comprises the following steps:

[0032] Step 1: Device Installation. Evenly space the fire extinguishing components on the air extraction pipes of the automatic detection system within the goaf. Ideally, the distance between adjacent fire extinguishing components should be 1 meter.

[0033] Step 2: Automatic fire extinguishing. According to the concentration of combustible gas, that is, CO, detected by the automatic detection system, combustible gas is usually a marker gas such as CO. Automatic fire extinguishing is divided into two ways, specifically:

[0034] When the automatic detection system does not detect the concentration of combustible gas in the goaf, the residual coal undergoes oxidation reaction and begins to heat up spontaneously. When the temperature reaches T0, the solid amine sealing material in the fire extinguishing component desorbs and releases carbon dioxide, inerting the goaf environment and suppressing spontaneous combustion of the residual coal. When the residual coal in the goaf loses the risk of spontaneous combustion and drops to room temperature, the solid amine material absorbs and stores the carbon dioxide in the goaf.

[0035] When the automatic detection system detects combustible gas in the goaf, the solid amine sealing material in the corresponding area is heated through the resistance wire according to the temperature detected by the temperature sensor and the concentration of the combustible gas, so that the solid amine sealing material automatically releases a certain amount of carbon dioxide, thereby extinguishing the fire. After the fire is extinguished, the heating of the solid amine sealing material is stopped, and the solid amine material is cooled to absorb carbon dioxide for storage. The total amount of carbon dioxide released is calculated according to the following formula:

[0036]

[0037] in, is the total amount of carbon dioxide released, in units of . It is the air leakage compensation coefficient, which is adjusted according to the complexity of the air leakage path. The value range is usually 0.5-1.2. The higher the value, the more complex the air leakage path. That is, 0.5 is used for simplicity and 1.2 is used for complexity. is the air leakage in the goaf, in units of . is the amount of coal left in the goaf, in tons, and and It is determined based on the mine site and is the basic parameter of the mine. Conventionally, the air leakage in the goaf is calculated based on the air supply, and the amount of coal left in the goaf can be calculated based on the coal loss rate during the mining process, which is generally 10%. The amount of coal left can then be calculated by multiplying the actual length, width and height of the working face by the coal loss rate.

[0038] is the residual coal coverage factor, in units of , adjusted according to the spontaneous combustion tendency of coal, the coverage coefficient of residual coal is usually in the range of 0.1-0.3, and the higher the spontaneous combustion tendency of coal, the higher the value, that is, low natural coal takes 0.1 and high volatile coal takes 0.3. It is the spontaneous combustion risk level of coal, which is divided into levels according to the volatile matter of coal. The value range is 1.0-1.5, and the higher the volatile matter of coal, the higher the value. Usually when the volatile matter of coal is less than 15%, that is, When <15%, is 1.0, when 15%≤ <25%, is 1.2, when When ≥25%, is 1.5.

[0039] It is the environmental risk level, which is divided into levels according to the detected gas concentration and temperature data. When the detected temperature is lower than TO and the combustible gas concentration is lower than the warning value, it is a low risk. When the temperature is between T0 and T1, or the concentration of combustible gas is between the warning value and the critical value, it is a medium risk. When the temperature is higher than T1 or the concentration of combustible gas is higher than the critical value, it is a high risk. It is 1.8, that is, when the gas concentration and temperature are distributed in different areas, the value with the higher risk is taken.

[0040] During coal spontaneous combustion, the critical temperature and critical values ​​of indicator gases vary depending on the geological characteristics of the mined coal seam. According to the national standard GB / T 44819-2024, the critical temperature for coal spontaneous combustion is divided into T0 and T1. T0 is the temperature at which CO is first detected, and T1 is the point where the CO concentration-temperature trend curve shows a sudden change. The CO concentration at T0 is determined as the warning value, and the CO concentration at T1 is determined as the critical value.

[0041] Because the solid amine sealing material in each fire extinguishing assembly is fixed, the amount of carbon dioxide released by each fire extinguishing assembly is also fixed. Based on the calculated total amount of carbon dioxide released, the number of fire extinguishing assemblies required to be heated in the area is determined to meet the required total amount of carbon dioxide released. In other words, by calculating the total amount of carbon dioxide released, the number of fire extinguishing assemblies required to extinguish a fire can be determined. The amount of carbon dioxide released by each fire extinguishing assembly can be calculated using existing techniques and will not be further elaborated here.

Claims

1. A carbon dioxide circulation capture fire extinguishing device, characterized by: The invention comprises a plurality of fire extinguishing components (10), each of which comprises a water-proof and breathable membrane (12) wrapped with a solid amine sealing material (11), the water-proof and breathable membrane (12) being arranged on a temperature sensor (13), the temperature sensor (13) being arranged on an air extraction bundle pipe (20) of an automatic detection system, a resistance wire with a heating function being arranged in the solid amine sealing material (11), a control unit being arranged on the temperature sensor (13), the control unit being electrically connected to the resistance wire and the temperature sensor (13), and each control unit being able to realize information transmission function and information reception function with a control center of the automatic detection system.

2. The carbon dioxide circulating capture fire extinguishing device according to claim 1, characterized in that: The fire extinguishing assembly (10) further comprises a protective shell, the protective shell cover being arranged outside the water-proof and breathable membrane (12), the temperature sensor (13) and the control unit, and the protective shell being provided with a plurality of first through holes for gas to pass through.

3. The carbon dioxide circulating capture fire extinguishing device according to claim 1, characterized in that: It also includes a hard protective cover (30) disposed outside each gas extraction bundle pipe, the hard protective cover (30) being provided with a plurality of second through holes for gas to pass through, and each fire extinguishing assembly being disposed within the hard protective cover.

4. The carbon dioxide circulating capture fire extinguishing device according to claim 1, characterized in that: The temperature sensor (13) is an optical fiber temperature sensor.

5. A method for automatic fire extinguishing in coal mine goaf, characterized in that: The steps include: S1: Device installation: The fire extinguishing assembly according to any one of claims 1 to 4 is evenly arranged at a certain distance on the air extraction bundle pipe arranged by the automatic detection system in the goaf; S2: Automatic fire extinguishing. When the automatic detection system fails to detect the concentration of combustible gas in the goaf, the coal will undergo oxidation reaction and begin to heat up spontaneously. When the temperature reaches T0, the solid amine sealing material in the fire extinguishing component will desorb and release carbon dioxide, inerting the goaf environment and suppressing the spontaneous combustion of the coal. When the coal in the goaf loses its spontaneous combustion hazard and drops to room temperature, the solid amine material will absorb and store the carbon dioxide in the goaf. When the automatic detection system detects combustible gas in the goaf, the solid amine sealing material in the corresponding area is heated through the resistance wire according to the temperature detected by the temperature sensor and the concentration of the combustible gas, so that the solid amine sealing material automatically releases a certain amount of carbon dioxide, thereby extinguishing the fire. After the fire is extinguished, the heating of the solid amine sealing material is stopped, and the solid amine material is cooled to absorb carbon dioxide for storage. The amount of carbon dioxide released is calculated according to the following formula: in, is the amount of carbon dioxide released, in units of , is the air leakage compensation coefficient, which is adjusted according to the complexity of the air leakage path. is the air leakage in the goaf, in units of , is the amount of coal left in the goaf, in tons. is the residual coal coverage coefficient, in units of , adjusted according to the tendency of coal spontaneous combustion, is the action time, the unit is , It is the risk level of spontaneous combustion of coal, which is divided into levels according to the volatile matter of coal. It is the environmental risk level, which is divided into levels according to the detected gas concentration and temperature data.

6. The automatic fire extinguishing method for coal mine goaf according to claim 5, characterized in that: The value range of the air leakage compensation coefficient is 0.5-1.2, and the higher the value, the more complex the air leakage path.

7. The automatic fire extinguishing method for coal mine goaf according to claim 5, characterized in that: The coverage coefficient of the residual coal ranges from 0.1 to 0.3, and the higher the spontaneous combustion tendency of the coal, the higher the value.

8. The automatic fire extinguishing method for coal mine goaf according to claim 5, characterized in that: The spontaneous combustion risk level of coal ranges from 1.0 to 1.5, and the higher the volatile matter of the coal, the higher the value.

9. The automatic fire extinguishing method for coal mine goaf according to claim 5, characterized in that: When the temperature is detected to be lower than T0 and the concentration of combustible gas is lower than the warning value, it is a low risk. When the temperature is between T0 and T1, or the concentration of combustible gas is between the warning value and the critical value, it is a medium risk. When the temperature is higher than T1 or the concentration of combustible gas is higher than 200ppm, it is a high risk. is 1.8.

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