KR20220134395A - System and Method for detecting spontaneous combustion in indoor coal yard - Google Patents

Abstract

Disclosed is a spontaneous fire breakout sensing system capable of sensing a spontaneous fire breakout occurrence portion of an indoor coal yard and suppressing spontaneous fire breakout through cooling fire extinguishment for the occurrence portion. The spontaneous fire breakout sensing system comprises: a measurement system detecting temperature information and gas information to detect a spontaneous fire breakout status of a coal pile stored in a coal block partitioned by a central bulkhead and a horizontal bulkhead in an indoor coal yard; a central control terminal calculating an array of low-coal fire breakout positions where the spontaneous fire breakout occurs using the temperature information and the gas information; and a spraying device sprinkling a fire extinguishing fluid to one of the array of the low-coal fire breakout positions according to a sprinkling control command.

Description

BACKGROUND ART System and Method for detecting spontaneous combustion in indoor coal yard

The present invention relates to a technology for controlling spontaneous ignition of a coal minefield, and more particularly, to coal

When spontaneous combustion occurs during the storage process of the pile, it detects carbon monoxide (CO) gas and a movable infrared temperature sensor, detects the spontaneous ignition site by automatic wireless transmission and reception, and can suppress spontaneous ignition through selective cooling and extinguishing of the generated part. A fire detection system and method are provided.

Coal is used as a basic raw material for thermal power plants worldwide due to its abundant reserves, low price, and stability of supply. Recently, the proportion of coal-fired power as a power source is increasing due to the increase in electricity demand due to electric vehicles, concerns about the risk of nuclear power generation, and the low base expansion of domestic renewable energy generation.

Accordingly, coal imports are increasing, and the import share and import volume of low-rank coal, which has many problems in spontaneous combustion, clinker generation, and composition, is also increasing significantly.

In the case of a 500MW standard coal-fired power plant, fuel coal is usually used after 1 to 3 months of coal storage.

In addition, when constructing a new coal-fired power plant, it is difficult not only to secure land for the construction of a coal-fired coal-fired power plant, but also to construct a new coal-fired coal mine due to friction and civil complaints between nearby residents and environmental groups. In order to solve these problems, the construction of a new coal yard is

Although it is being built as an indoor type, it is not possible to fundamentally prevent the spontaneous ignition problem of low-grade coal even with an indoor type storage yard. many.

In case of spontaneous combustion, major combustion gases such as carbon dioxide (CO ₂ ), carbon monoxide (CO), and water vapor (H ₂ O) and 66 organic compounds such as benzene, toluene, and acetic acid are generated, resulting in deterioration of the surrounding environment and increased odor generation. This is a cause of environmental complaints.

In the case of Korea, which is an energy importing country, heat loss of 1.5 to 5.8% into the air is also acting as a factor in raising the unit cost of power generation. Low Rank Coal (LRC) is divided into grades from peat to brown coal, lignite, sub-bituminous coal, bituminous coal, and anthracite. Bituminous coal is further divided into low volatile matter, medium volatile matter, and high volatile matter bituminous coal, and anthracite is divided into semi-anthracite, anthracite, Meta-anthracite and graphite-based anthracite.

Among them, low-grade coal (LRC) refers to from brown coal to sub-bituminous coal, and is classified from bituminous coal to high-grade coal (Hard Coal; High Rank Coal).

Low-grade sub-bituminous coal has many pores and has many peripheral hydrocarbons (volatiles), so the temperature rises due to the accumulation of heat of adsorption by adsorption and desorption of moisture. Oxidation reaction of group (-COOH) and carbony group (-C=O) raises the temperature inside the pores, which may cause spontaneous ignition.

Spontaneous ignition of coal-fired power plants occurs frequently about 8,000 to 10,000 times a year due to the increase in the use of low-grade coal, and the ignited coal type ratio is reported to be over 56%.

When coal spontaneously ignites, it not only loses heat (loss rate of about 5.8% or less) of the coal itself, but also deteriorates the working environment in the coal yard due to harmful gas and fumes generated during coal ignition, and causes civil complaints in the surrounding area. .

In addition, the risk of large-scale damage to equipment such as fire and dust explosion in the pulverizer system is increasing, which causes combustion failure due to heat loss and in the process of transport using a conveyor belt.

The existing countermeasures against spontaneous combustion can be divided into two main types as follows. The first is a method of blocking contact with moisture or oxygen in the atmosphere by applying/spraying a coating agent or a dusting agent using a cement hardener and a polymer hardener, etc. to a coal pile.

Second, there is a method of adsorbing oil to dry coal at a high temperature, or transforming the surface through compression or molding. However, in the case of the first method, it is difficult to fundamentally block the infiltration of moisture and oxygen, which is easy to be detached from rain or strong wind, and it is also a cause of fine powder and combustion failure when input into the boiler.

In addition, the second method is not very effective in consideration of economic feasibility because too much energy is input to transform the surface reforming of low-grade coal, and there is no case applied to actual coal-fired power plants.

In the existing technology, there is a method of suppressing ignition by installing a sintering filter that is stable even at a temperature of 250℃ in the pressure vessel to remove dust. In addition, there is disclosed a system for preventing fires occurring inside the differentiator in advance by providing the inside of the differentiator so that it can be monitored through a plurality of sensors around the entrance/exit portion of the differentiator. In addition, there is disclosed a method of alarming a fire by monitoring in real time a unique light source wavelength band and a unique temperature color of combustion products (ultraviolet, infrared by heat, flame) generated in a fire by being installed in the pulverizer.

In addition, there is disclosed a disaster prevention system that measures the level of pure oxygen concentration in the differentiator and sets a support signal therefor to sound an alarm in case of danger. In addition, there is disclosed a coal temperature automatic detection system capable of automatically detecting the surface temperature of a pile of coal stored for a long time in a yard to prevent spontaneous combustion therein.

In addition, an infrared camera installed inside the sealed storage to monitor the raw material files loaded in the sealed storage, a gas component detection sensor to detect gas components inside the sealed storage, and a spraying unit that sprays fire extinguishing agent when fire is detected. An apparatus is disclosed.

However, when coal resources are scarce as in Korea, low-grade coal that inevitably ignites and/or fires frequently is imported and used. Accordingly, there is a need for an invention capable of fundamentally preventing spontaneous ignition and/or fire in an indoor coal storage that provides a fatal cause to the working environment such as suffocation due to difficulty in air diffusion.

In particular, recently, coal imported from Southeast Asia occupies a large proportion. When coal-fired power plants are shut down due to special measures against fine dust in the spring, the mined coal is stored in a yard before being loaded onto a carrier. Therefore, spontaneous ignition has already started during the stockpiling process, causing a fire in the transport ship, and the proportion of coal showing a high surface temperature and flame at the time of unloading is increasing.

Already, in the case of coal that has been ignited, spontaneous ignition occurs immediately upon unloading or within one week after unloading, causing various problems. Therefore, there is an urgent need for a method of spontaneous ignition through fire extinguishing in the process of unloading and storing coals that have been basically spontaneously ignited.

In addition, when spontaneous ignition or fire occurs in an indoor coal yard, it is difficult to extinguish the fire with a fire extinguisher such as emulsion or carbon dioxide.

Therefore, from the initial point in time when spontaneous ignition starts at low temperature in the indoor coal yard, it fundamentally detects the ignition gas and detects the ignition location and surface temperature to fundamentally solve the spontaneous ignition phenomenon and do not cause additional problems like the above methods. Effective spontaneous ignition detection and control measures are absolutely necessary.

In addition, conventionally, a method of applying/spraying a coating agent or a dusting agent to the surface of a coal pile is mainly applied as a countermeasure against spontaneous ignition, and a method of additionally modifying the surface modification of coal has been proposed. However, these methods are highly likely to cause problems in coal transport and storage facilities such as conveyor belts, coal silos and pulverizers, and also cause unburned dust and combustion failure in the boiler furnace.

In addition, the method of modifying the surface of coal requires too much energy to obtain the effect of preventing spontaneous ignition and requires additional equipment, which is high in cost compared to the effect of preventing spontaneous ignition. There are no cases

1. Korea Patent No. 10-0799294 (Registration Date: January 23, 2008)

The present invention has been proposed to solve the problem according to the above background art, and a spontaneous ignition detection system and method capable of detecting a spontaneous ignition occurrence site of an indoor coal storage and suppressing spontaneous ignition through selective cooling and extinguishing of the occurrence part Its purpose is to provide

Another object of the present invention is to provide a self-ignition detection system and method capable of precisely measuring a location where spontaneous combustion occurs in an indoor coal yard and a surface temperature of the location.

The present invention provides a spontaneous ignition detection system capable of detecting a spontaneous ignition occurrence site of an indoor coal storage and suppressing spontaneous ignition through selective cooling and extinguishing of the occurrence part in order to achieve the object presented above.

The spontaneous ignition detection system,

a measuring system that detects temperature information and gas information to detect the spontaneous ignition state of coal piles stored in coal piles divided by a central bulkhead and a horizontal bulkhead in an indoor coal pit;

A central control terminal that calculates a low carbon ignition position arrangement in which the spontaneous ignition occurs by using the temperature information and the gas information, and generates a spray control command for extinguishing fluid for removing the spontaneous ignition state according to the low carbon ignition position arrangement ; and

and a spraying device for spraying the extinguishing liquid to one of the low carbon ignition positions according to the spraying control command.

In addition, the measuring system, a gas detection sensor for detecting the gas information from a predetermined surface depth of the coal pile; and a temperature sensor configured to detect the temperature information from the surface of the coal pile while moving along a preset movement trajectory line as the gas information is detected.

At this time, it is characterized in that the low carbon ignition position arrangement 350 is changed according to the movement of the temperature sensor.

The gas detection sensor may include a first gas detection sensor and a second gas detection sensor having a predetermined height from the upper portions of the central partition wall and the horizontal partition wall and installed at a predetermined distance from each other.

In addition, in the case of the moving track line, the first line pattern of the moving track line corresponding to the section of the first inclined surface G1 on the lower floor and the second inclined surface G2 connected to the first inclined surface G1 The distance between the plurality of transverse lines formed is formed to decrease toward the end section of the second inclined surface G2, and from the third inclined surface G3 and the third inclined surface G3 connected from the second inclined surface G2. The interval between the plurality of transverse lines forming the second line pattern of the moving orbit line corresponding to the section of the continuous fourth inclined surface G4 is characterized in that it increases toward the end section of the fourth inclined surface G4.

In addition, the spray angle slope of the extinguishing liquid from the first inclined surface G1 to the second inclined surface G2 is 5 to 20°, and from the second inclined surface G2 to the third inclined surface G3 is the amount of the extinguishing liquid. The injection angle slope is 20 to 30°, and the injection angle slope of the fire extinguishing liquid from the third inclined surface G3 to the fourth inclined surface G4 is 30 to 45°.

In addition, the particle size distribution of the first inclined surface G1 is 52.5 to 25.8 mm, the particle size distribution of the second inclined surface G2 is 41.8 to 18.8 mm, and the particle size distribution of the third inclined surface G3 is 19.0 to 4.3. mm, and the particle size distribution of the fourth inclined surface G4 is 4.5 to 2.5 mm.

In addition, from the first inclined surface (G1) to the second inclined surface (G2), the firing frequency for the spontaneous ignition is characterized in that 70 to 90%.

In addition, the moving track line has a third interval spaced apart from each other from the first top surface starting from the top of the coal pile to the contact surface reaching the central bulkhead, the third interval being greater than the first interval, but 2 It is characterized in that the distance is smaller than the interval.

In addition, from the contact surface (T1) to the central partition wall, the injection angle of the fire extinguishing liquid is characterized in that the slope is 50 to 60 °.

In addition, the particle size distribution of the first top surface T2 is 3.2 to 2.4 mm, and the particle size distribution of the contact surface T1 is 3.2 to 33.2 mm.

In addition, the ignition frequency for the spontaneous ignition on the contact surface T1 is characterized in that 10 to 30%.

In addition, it is characterized in that the liquid-to-liquid ratio of 0.045 to 0.08L fire extinguishing water/kg coal amount of hatan in the optimum fire extinguishing efficiency pressure range of 8-11 kgf/cm 2 when the injection nozzle of the injection device is operated.

In addition, the extinguishing solution is a coating film of calcium salt on the surface of the coal through a saponification reaction with oil ((HO-CO-CH ₂ ) _n ) of the coal surface of the coal pile ((Ca-(O-CO-CH ₂ ) ₂ ) It is characterized in that 3-9mg CaCO ₃ /1.0 ℓH ₂ O to form a.

In addition, the central control terminal is characterized in that if the temperature information is less than 50 ℃, stopping the spray control command.

On the other hand, in another embodiment of the present invention, (a) the measurement system is temperature information and gas to detect the spontaneous ignition state of the coal pile stored in the coal storage block partitioned by the central bulkhead and the horizontal bulkhead in the indoor type coal pit. detecting information; (b) the central control terminal calculates the low carbon ignition position arrangement in which the spontaneous ignition occurs by using the temperature information and the gas information, and a fire extinguishing solution for removing the spontaneous ignition state according to the low carbon ignition position arrangement 350 generating a spray control command; and (c) spraying, by the spraying device, the extinguishing liquid to one of the low carbon ignition positions according to the spray control command.

According to the effect of the present invention, it is possible to obtain a very large effect, such as prevention of spontaneous ignition of low-grade coal and long-term storage.

In addition, as another effect of the present invention, it is possible to detect the ignition position through a carbon monoxide detection at the initial stage in which it is difficult to visually distinguish the coal that has been ignited and detect the ignition position with a mobile infrared measuring instrument.

In addition, as another effect of the present invention, the initial position of ignition has a cooling effect through nozzle inclination adjustment and selective fire extinguishing, while forming a hard calcium salt film produced by the endothermic and saponification reaction of calcium carbonate within the low carbon period to form oxygen on the surface of coal. cut off contact

Therefore, it is possible to effectively detect and control spontaneous ignition.

In addition, as another effect of the present invention, calcium salt (Ca-(O-CO-CH ₂ ) ₂ ), which is a by-product of calcium carbonate incidentally, improves the desulfurization efficiency in the furnace and reduces greenhouse gas emission when burning in a boiler. Therefore, it is possible to realize an eco-friendly power generation industry and a clean coal-fired power plant.

1 is a structural conceptual diagram of an indoor type coal storage field according to an embodiment of the present invention.
Figure 2 is a prediction diagram of the location of spontaneous ignition of coal piles in an indoor coal mine according to an embodiment of the present invention.
3 is a block diagram illustrating the configuration of an indoor coal storage spontaneous ignition detection system according to an embodiment of the present invention.
4 is a flowchart showing the operation of detecting carbon monoxide (CO) and surface temperature of ignited coals, and operating a fire extinguishing liquid driving pump and an injection nozzle device according to an embodiment of the present invention.
5 is a conceptual diagram illustrating an indoor coal storage spontaneous ignition detection, an extinguishing fluid driving pump, and a nozzle injection operation according to an embodiment of the present invention.
6 is a block diagram of the central control terminal shown in FIG.
7 is a three-dimensional view of one block divided by bulkheads of an indoor coal storage shed according to an embodiment of the present invention.
FIG. 8 is a plan view of FIG. 7 .
9 is a driving concept of the fire extinguishing water injection device according to the movement arrangement of the temperature sensor according to an embodiment of the present invention.
10 is a cross-sectional view of an indoor coal storage bulkhead and an actual coal pile of coal according to an embodiment of the present invention.
11 is a graph showing the temperature change of the ignition-generated ignited coals according to the pressure of the extinguishing agent injection nozzle according to an embodiment of the present invention.
12 is a graph showing a change in the amount of fire extinguishing liquid injection amount (liquid height ratio) compared to the amount of stored ignition carbon for each pressure of the fire extinguishing agent injection nozzle according to an embodiment of the present invention.
13 is a view showing the measurement of the spray length for each inclination of the fire extinguishing water spray nozzle according to an embodiment of the present invention.
14 is a diagram illustrating the installation of a temperature change measuring sensor after unloading of a coal pit ignited coal according to an embodiment of the present invention.
15 is a table showing changes in temperature for each storage period and location according to an embodiment of the present invention.
16 is a table showing a 50 cm depth temperature sensor, an infrared surface temperature change, and a carbon monoxide concentration change according to an embodiment of the present invention.
17 is a graph showing the results of measuring the internal temperature at a depth of 50 cm for each slope for each period of expected spontaneous combustion coal storage according to an embodiment of the present invention.
18 is a graph showing a comparison value between a result of measuring a temperature of 50 cm in depth of a spontaneous ignition section with a t-type sensor and a surface temperature sensed by a mobile infrared measuring device according to an embodiment of the present invention.
19 is a graph showing the change in the CO concentration for each period of coal storage after unloading of spontaneously ignited coal according to an embodiment of the present invention.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and will be described in detail in the detailed description. However, this is not intended to limit the present invention to a specific embodiment, it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

In describing each figure, like reference numerals are used for like elements. The terms first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another.

For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The term “and/or” includes a combination of a plurality of related listed items or any of a plurality of related listed items.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. shouldn't

Hereinafter, an indoor coal storage spontaneous ignition detection system and method according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In general, water is the best extinguishing agent and coolant that can cool 639 kcal per 1 kg. It is known that the total caloric loss of coal is 80~320 kcal/kg, which is 1.5~5.85% of 5,400 kcal/kg, but if coal is extinguished immediately after ignition at 200°C or less before a flame occurs, it will be as low as 30 kcal/kg. it is known

Water is hydrophilic, so it can extinguish most fires efficiently by cooling, but it has low wettability and contact with the hydrophobic coal and oil components. I don't use it because I can't have it.

Of course, by adding surfactants and organic additives, wettability with oil is increased, but in use, toxic gases such as organic compounds are avoided due to generation of toxic gases. Therefore, the wettability can be improved by the forced contact method by using a fire extinguishing solution in which a small amount of calcium carbonate used as a desulfurization agent for fine dust precursors (SO ₂ ) in the exhaust gas of a boiler in a thermal power plant is hardly toxic in operation.

As such, in order to effectively detect and suppress the spontaneous combustion phenomenon of coal mines where coal is handled and stored on a large scale, when it is difficult to distinguish spontaneous combustion with the naked eye at the beginning of spontaneous combustion when the predicted coal is stored, it occurs in the low temperature section. A method of detecting a spontaneous ignition location having a surface temperature of 100°C or higher by driving a portable infrared temperature measuring device for measuring a spontaneous ignition location after detecting carbon monoxide (CO); A method of selectively absorbing the heat of the coal surface using calcium carbonate extinguishing water at the location of ignition and forming a film on the coal surface to prevent oxygen absorption; It is possible to derive a fire extinguishing method for efficiently contacting hydrophilic calcium carbonate digested water with hydrophobic high temperature coal surface and increasing wettability.

First, a carbon monoxide detection sensor and a wireless transmitter for detecting carbon monoxide (CO) generated from the start of low-temperature (100-150°C) ignition are provided on the upper part of the indoor storage, so the lowest temperature ignition that cannot detect spontaneous combustion with the naked eye Carbon monoxide (CO) generated from the starting point is lighter than air and moves to the upper part immediately after it is generated, so it detects the carbon monoxide (CO) rising to the top of the coal pile in the coal storage bulkhead and detects the internal temperature 50cm deep from the surface of the coal where spontaneous combustion begins. Thus, it can be configured to measure whether spontaneous ignition is initiated.

Second, when carbon monoxide (CO) is detected, a movable infrared sensor is automatically attached to the rotating line and moves from the bottom of the slope to the top wall by the height of the coal pile. can do.

The area with the highest frequency of spontaneous ignition has more granulated material than on the slope of the lower floor, and from the slope of the lower floor, where the updraft flows the most, to the 1/3 point of the slope, the distance between the moving trajectories of the infrared measuring device is dense, and the frequency of spontaneous combustion It is composed sparsely differently as it gets farther from the top where is lowered, and the slope from the top, which is the second bundle point, to the central bulkhead constitutes the second densely spaced temperature sensor.

Third, spontaneous combustion occurs during the coal low coal period, and spontaneous combustion can be suppressed only when the surface temperature of coal with a surface temperature of 80 to 200°C is stored at 25°C or less through cooling. In order to absorb the heat and generated gases (CO,CO ₂ ) from the surface of the coal with a high surface temperature, the solubility of 3~9mg CaCO ₃ /1L H ₂ O is used to absorb the heat of the coal surface and the exhaust gas carbon dioxide (CO ₂ ) It reacts with calcium bicarbonate (Ca(HCO ₃ ) ₂ ) to form calcium bicarbonate ₍ Ca-(O-) By forming a CO-CH ₂ ) ₂ ) film, it is possible to block the contact between the coal surface and oxygen, thereby suppressing the progress of spontaneous combustion.

CaCO ₃ + CO ₂ + H ₂ O + Heat → Ca(HCO ₃ ) ₂ <Reaction of coal surface ignition gas and heat absorption>

Ca(HCO ₃ ) ₂ + (HO-CO-CH ₂ )n (coal surface component)

→ Ca-(O-CO-CH ₂ ) ₂ + CO ₂ + H ₂ O <Saponification reaction>

In particular, the saponified compound (Ca-(O-CO-CH ₂ ) ₂ ) reacts with the fine dust precursor (SO2) generated in the boiler when reburning in the boiler to generate gypsum, so it is very beneficial because it acts as a desulfurization additive. .

Ca-(O-CO-CH ₂ ) ₂ + SO ₂ + O ₂ → CaSO ₄ + H ₂ O + CO ₂

Fourth, since the surface of coal is hydrophobic, it does not wet with water and does not react, so the injection pressure is maintained in the range of 7-10 kgf/cm 2 to increase the frequency and wettability of the surface of the coal by adopting a physical forced contact method. By spraying a nozzle that is capable of being able to fire at an angle of 5 to 25° vertically from the ground surface, the upper third of the slope is cooled and extinguished from the floor where the ignition frequency is 70 to 90%, and the ignition frequency is 10 to 30. %, the ignition position from the top to the middle wall is cooled to 25°C or less of the surface temperature of the coal from 100 to 250°C through selective cooling and fire extinguishing through nozzle injection that is inclined 50-60° vertically from the top of the ground. can be configured.

Fifth, the calcium carbonate fire extinguishing water spray nozzle is configured to automatically move along the central axis of the infrared temperature meter when the arrangement changes depending on the location of the ignition according to the arrangement of the red line temperature meter attached to the movable rotation line. Thus, it is configured to be automatically sprayed when an ignition starter over 100℃ is detected. In addition, the liquid height ratio, which represents the ratio of extinguishing liquid and ignition amount, is configured to operate with 0.04 to 0.08ℓ extinguishing water/kg coal. It is possible to provide a method of preventing ignition by detecting and extinguishing effective ignition initiation coal through an on-off method of stopping the operation of the engine.

1 is a structural conceptual diagram of an indoor type coal storage 100 according to an embodiment of the present invention. In particular, FIG. 1 is a structural conceptual diagram of an indoor type coal storage that is constructed and operated in a coal-fired power plant. The indoor coal storage yard 100 is basically installed with a roof 20 on the ground 10, and is divided into a longitudinal long-axis bulkhead and a transverse short-axis bulkhead 110 in the roof 20, and is divided into bulkheads. It is possible to store the desired coal 150 for each divided compartment. That is, the coal pile 150 is stored inside by dividing by the inclined bottom surface 50 descending toward the central bulkhead 111 . The coal pile 150 may mean individual coals or may mean a single lump of coals.

In addition, since the conveyor unit 180 for transporting coal is installed in the same direction as the long axis bulkhead, the coal extraction unit 141 of the reclaimer 140 moves toward the conveyor belt 131 of the conveyor unit 130 for coal transport. When the 150 is pushed, the conveyor belt 131 moving by the conveyor roller 132 transfers the coal to a pulverizer silo (not shown).

A temperature sensor 121-1 for measuring the temperature of the ignition starting coal during unloading is installed in the coal storage unit 120 . When spontaneous ignition is initiated within the central bulkhead 111, the transverse bulkhead 110, and the outwardly inclined bottom surface 50, the coal pile 150 at a depth of about 50 cm, it is indistinguishable with the naked eye and occurs at the beginning of spontaneous ignition. A gas detection sensor 121-2 for detecting carbon monoxide (CO), and a communication device (not shown) for transmitting the sensed data are configured.

When carbon monoxide (CO) is detected, the detection sensor 121-2 for detecting the location of ignition by measuring the surface temperature of the coal pile is moved along the trajectory line to the slope of the coal pile and the slope of the uppermost bulkhead (circulation) and The movement trajectory line is configured to move back (recirculate).

The injection device 160 that receives the data sensed by the measurement system 121 wirelessly and sprays fire extinguishing water is disposed between the conveyor belt 130 and the indoor coal storage reclaimer 140 . The measuring system 121 includes a temperature sensor 121-1 for measuring the temperature of the ignition starter and a gas detection sensor 121-2 for detecting carbon monoxide (CO).

Figure 2 is a prediction diagram of the spontaneous ignition of the coal pile of the indoor type coal yard 100 according to an embodiment of the present invention. Referring to FIG. 2 , it is basically divided into a longitudinal bulkhead and a short-axis bulkhead 110 in the horizontal direction, and is divided by an inclined bottom surface 50 descending toward the central bulkhead 111 to store coal inside. . In addition, in the case of coal that is expected to be spontaneously ignited, there is a particle size distribution characteristic of the inclined surface 211 and the central bulkhead 111 in which coarse powder is accumulated in the lower part and fine powder is accumulated in the upper part in the coal storage process. Therefore, in the inclined surface 211, a porosity occurs at the 1/3 point from the bottom of the lower inclined surface, and air communication is smooth, so that 70 to 90% (210) of the spontaneous ignition 212 is achieved with the central partition wall 111 in the case of the upper part. 10 to 30% (220) of the spontaneous ignition 222 is generated at the uppermost bulkhead contact surface where the collision airflow occurs.

3 is a block diagram of an indoor coal storage spontaneous ignition detection system 300 according to an embodiment of the present invention. Referring to FIG. 3 , the control system 300 for the coal storage spontaneously ignited coal may include a coal ejector 120 , a measurement system 121 , a central control terminal 310 , an injection device 160 , and the like.

The coal ejector 120 performs a function of dropping (that is, lowering coal) downward from the indoor coal yard.

The measuring system 121 detects the spontaneous ignition state of the coal pile and performs a function of generating temperature information and gas information. To this end, the measuring system 121 may include a temperature sensor 121-1 for generating temperature information and a gas detection sensor 121-2 for generating gas information. The temperature sensor 121-1 may be mainly an infrared temperature sensor, and the Gam detection sensor 121-2 may mainly be a carbon monoxide (CO) detection sensor.

The central control terminal 310 is connected to the measurement system 121 through the communication device 301 . Of course, the communication device 301 connects the measurement system 121 and the central control terminal 310 through a communication network. At this time, as the communication network, a wireless communication network such as IrDA (Infrared Data) communication, wireless LAN (Local Area Network), Bluetooth, LiFi (Light Fidelity), WiFi (Wireless Fidelity), NFC (Near Field Control), etc. may be used, but in this It is not limited, and may be S232, RS485, Modbus, CC-Link communication, Ethernet communication, or the like. Of course, in addition to Public Switched Telephone Network (PSTN), Public Switched Data Network (PSDN), Integrated Services Digital Networks (ISDN), Broadband ISDN (BISDN), Local Area Network (LAN) , a metropolitan area network (MAN), a wide area network (WLAN), or the like.

The central control terminal 310 determines whether spontaneous ignition has started using the temperature information and gas information obtained through the measurement system 121, and as a spontaneous ignition state according to the determination result, carbon monoxide (CO) and the surface of the coal It generates a spray control command that automatically sprays to the ignition location where the temperature is detected over 100℃. On the other hand, if it is less than 50° C., it is automatically turned off.

The central control terminal 310 may be a server, a personal computer, a notebook computer, or the like.

The injection device 160 may include a driving pump 320 , a spray nozzle 330 , a fire extinguishing liquid supply unit 340 , and the like. The driving pump 320 receives the extinguishing fluid from the extinguishing fluid tank 340 and supplies it to the spray nozzle 330 .

The spray nozzle unit 330 has a plurality of spray nozzles that can be adjusted in angle. The digestive fluid supply unit 340 performs a function of storing the digestive fluid. As the digestive fluid, water may be typically used, but is not limited thereto, and may be calcium carbonate, magnesium carbonate, or the like.

Accordingly, the coal loaded on the coal transport belt at the top of the indoor coal mine is loaded into the indoor coal mine through the coal ejector 120 of the coal miner. When the coal is lowered, the lower outer temperature measuring device 121 connected to the coal ejector 120 is automatically operated, and when the temperature measuring device 121 detects coal with a surface temperature of 80° C. or higher, the communication device 301 transmits the temperature information to the center. It is transmitted to the control terminal 310 side.

The central control terminal 310 that has received the signal drives the driving pump 320 , and the injection nozzle 330 is operated through the driving pump 320 in the extinguishing fluid supply unit 340 , and the temperature of the coal surface is 80° C. It is configured so as not to operate the driving pump 320 when lowering to less than.

Coal is piled up in the form shown in FIG. 1 , and spontaneous combustion begins as the low coal period passes. When spontaneous ignition is initiated near the surface depth of about 50 cm of the coal pile 150, carbon monoxide (CO) gas is first generated. The generated carbon monoxide (CO) is lighter than air and moves to the detection sensor 121-2 that detects carbon monoxide (CO) attached to the roof side of the coal storage bulkhead, and the detection sensor 121-2 detects carbon monoxide (CO). When this occurs, the temperature sensor 121-1 is automatically operated to detect the location where the ignition occurred.

When the temperature sensor 121-1 detects a coal surface temperature of about 100° C. or higher, the communication device 301 transmits temperature information to the central control terminal 310 . The central control terminal 310 that receives the signal drives the extinguishing fluid driving pump 320 , and the extinguishing fluid spray nozzle 330 is operated from the extinguishing fluid supply unit 340 through the extinguishing fluid driving pump 320 .

When the temperature of the coal surface decreases to less than about 25° C., the extinguishing fluid drive pump 320 is turned off. The surface temperature sensing of the coal pile 150 is performed by a temperature sensor 121-1 installed on the upper roof of the coal pile to move from outside to inside in a matrix form. The arrangement of the temperature sensor 121-1 for each position on the inclined surface and the central bulkhead side changes according to the movement, so that when the low carbon ignition position arrangement 350 moves in different directions (a, b, c, d, e, f), By giving a signal to the communication device 301 and the central control terminal 310, the spray nozzle 330 may be configured to automatically move to the central axis of the arrangement of the temperature sensor 121-1.

In an embodiment of the present invention, when low rank coal, which spontaneously ignites frequently, is stored in the indoor coal yard 100, spontaneous ignition is initiated through the detection of carbon monoxide (CO) gas generated at the initial stage of spontaneous ignition. Detect and measure the location of spontaneous ignition and/or the surface temperature of the location using the movable temperature sensor 121-1.

By operating the injection nozzle 330 having a high-pressure injection nozzle for calcium carbonate (CaCO ₃ ) fire extinguishing water installed on the bottom side of the coal pit, it cools and extinguishes the fire through selective fire extinguishing water injection at the location of the ignition and forms a calcium salt film on the surface of the coal. It is possible to continuously suppress spontaneous ignition through oxygen blocking. At this time, the hydrophobic coal is forcibly brought into contact with the hydrophilic fire extinguishing water, and the average particle diameter of about 50 mm coal that has been ignited at 100 to 250 ° C through heat absorption of calcium carbonate is cooled and digested to about 25 ° C or less. do.

_In particular, _the coal stored during cooling and digestion is _a hard calcium salt film ( Forms (Ca-(O-CO-CH ₂ ) ₂ ) to block contact with oxygen and inhibits spontaneous ignition. In addition, porosity is accumulated by accumulating granular particles with a frequency of about 70-90% of spontaneous ignition of low carbon stock. Suppresses spontaneous ignition of the entire surface through selective cooling and fire extinguishing from the high slope of the floor to the third point of the slope and the topmost wall contact with a firing frequency of 10 to 30%.

FIG. 4 is a flowchart showing the operation process of sensing carbon monoxide (CO) and surface temperature of ignited coals, and operating the extinguishing liquid driving pump 320 and the injection nozzle 330 according to an embodiment of the present invention. Referring to FIG. 4 , carbon monoxide (CO), which is first generated at low temperature due to spontaneous combustion, is detected by the gas detection sensor 121-2, and the detection area is detected by the left and right sensors at intervals of less than 10m on the left and right, and the ignition position is measured The temperature sensor 121-1 is driven (steps S401, S402, S410, and S420).

The temperature sensor 121-1 is configured to rotate left and right according to the slope position and the left and right sides, and the moving temperature sensor 121 measures the surface temperature of the stored coal according to the arrangement of each position of the coal storage unit to measure about 100 When a temperature of ℃ or higher is detected, the communication device 301 receives a signal and transmits it to the central control terminal 310, and the central control terminal 310 gives a signal to operate the drive pump 320 and the spray nozzle 330, , the central control terminal 310 is

In order to operate the digestive fluid driving pump 320, the central control terminal 310 supplies power to the extinguishing fluid driving pump 320 (steps S430, S440, S450).

When power is supplied to the extinguishing fluid driving pump 320, the extinguishing fluid from the extinguishing fluid supply unit 340 is sucked into the extinguishing fluid suction confluence pipe (not shown), and is sucked into the extinguishing fluid driving pump 320 through the suction amount control valve (not shown). (Steps S471, S472, S473, S481, S482).

The extinguishing fluid sucked into the suction confluence pipe (not shown) flows into the discharge confluence pipe (not shown) through the pump flow control valve (not shown), and is supplied to the nozzle through the control of the opening degree of the extinguishing fluid pump flow control valve (not shown). pressure can be adjusted. The extinguishing liquid flowing into the discharge confluence pipe (not shown) is sprayed onto the coal surface to be lowered by the spray nozzle 330 through a flow meter (not shown) and a pressure gauge (not shown) (steps S483, S484, S485, S487). ).

The flow rate of fire extinguishing water flowing into the spray nozzle device 330 is measured by a flow meter (not shown), and the pressure supplied to the spray nozzle device 330 is measured by a pressure gauge (not shown). That is, it is configured to control the pressure supplied to the spray nozzle unit 330 by adjusting the opening degree of the extinguishing fluid pump flow rate control valve (not shown).

On the other hand, the central control terminal 310 drives a motor (not shown) at the same time as supplying power to the driving pump 320, and adjusts the position of pushing and pulling the position of the spray nozzle 330 to move along the central axis of the temperature sensor array. It is configured to move left and right by driving a screw (not shown). When the position adjusting screw (not shown) rotates, the injection nozzle 330 moves to the left or right to adjust the position of the nozzle injector 330 to match the low carbon ignition position arrangement 350 (steps S461 and S462).

An angle adjustment plate (not shown) for adjusting the inclined surface spray angle of the spray nozzle device 330 is

When turning right, the rotation angle of the spray nozzle device 330 is increased upward, and when turning left, the rotation angle of the spray nozzle device 330 is returned to the vertical direction by the spring (elastic body) connected to the ground surface nozzle support and the nozzle injection side ( Steps S463, S464). On the other hand, the inclination to the low coal slope with respect to the ground surface is configured to be adjustable at any time.

5 is a conceptual diagram illustrating an indoor coal storage spontaneous ignition detection, an extinguishing fluid driving pump, and a nozzle injection operation according to an embodiment of the present invention. Referring to FIG. 5 , the spray nozzle 501 of the spray nozzle unit 330 is supported by an angle adjustment plate 502 , and the angle adjustment plate 502 is connected to a position adjustment ball screw 503 . In addition, a motor 504 for rotating the position adjusting ball screw 503 is configured.

The flow rate of the extinguishing liquid flowing into the spray nozzle 501 is measured by the flow meter 510 , and the pressure supplied to the spray nozzle 501 is measured by the pressure gauge 520 . That is, the pressure supplied to the nozzle of the spray nozzle 501 can be adjusted by adjusting the opening degree of the extinguishing fluid pump flow rate control valve (not shown).

In addition, a wireless communication circuit 540 for wireless communication may be configured in the central control terminal 310 . Of course, the central control terminal 310 may be configured to include a modem for wired communication. The first and second communication terminals 531 and 532 may be configured between the central control terminal 310 and the flowmeters/pressure gauges 510 and 520 .

The first and second communication terminals 531 and 532 are composed of a wired/wireless transceiver (not shown), a microprocessor, a memory, a display, and the like. The display may be a liquid crystal display (LCD), a light emitting diode (LED) display, a plasma display panel (PDP), an organic LED (OLED) display, a touch screen, a cathode ray tube (CRT), a flexible display, or the like.

6 is a configuration block diagram of the central control terminal 310 shown in FIG. Referring to FIG. 6 , the central control terminal 310 may include an input unit 610 , a calculation unit 620 , a control unit 630 , an output unit 640 , and the like.

Referring to FIG. 6 , the input unit 610 collects and receives information generated from the measuring meter 121 , the pressure gauge 520 , the flow meter 510 , and the like. Of course, the input unit 610 may be directly connected to the measuring meter 121 , the pressure gauge 520 , and the flow meter 510 , or may be connected only to the communication device 301 and/or the communication terminals 531 and 532 .

The calculator 620 performs a function of calculating a measured value by using measurement information measured by the measuring meter 121 , the pressure gauge 520 , the flow meter 510 , and the like. In addition, the temperature information is monitored to perform a function of comparing the temperature information with a preset reference value. Of course, it performs a function of comparing the measured pressure and flow with preset values.

The control unit 630 generates a control command according to the comparison result generated in the calculation unit 620, and transmits it to the injection device 160, the communication device 301 and/or the communication terminals 531 and 532 to control the function. carry out

The output unit 640 performs a function of displaying information processed by the calculation unit 620 , the analysis unit 630 , and the like. Accordingly, the output unit 640 may generate notification information using a combination of text, voice, and graphics. To this end, the output unit 640 may include a display, a sound system, and the like.

The display may be a liquid crystal display (LCD), a light emitting diode (LED) display, a plasma display panel (PDP), an organic LED (OLED) display, a touch screen, a cathode ray tube (CRT), a flexible display, or the like. In the case of a touch screen, it may function as an input means.

The calculation unit 620 and the analysis unit 630 illustrated in FIG. 6 mean a unit for processing at least one function or operation, which may be implemented in software and/or hardware. In hardware implementation, an application specific integrated circuit (ASIC), digital signal processing (DSP), programmable logic device (PLD), field programmable gate array (FPGA), processor, microprocessor, other It may be implemented as an electronic unit or a combination thereof. In software implementation, software composition component (element), object-oriented software composition component, class composition component and task composition component, process, function, attribute, procedure, subroutine, segment of program code, driver, firmware, microcode, data , databases, data structures, tables, arrays, and variables. Software, data, etc. may be stored in a memory and executed by a processor. The memory or processor may employ various means well known to those skilled in the art.

7 is a three-dimensional view of one block divided by partitions of the indoor coal storage 100 according to an embodiment of the present invention. Referring to FIG. 7 , a total of 40 blocks of 20 coal storage blocks are installed on either side of the central bulkhead 111 in a typical indoor coal storage yard.

As shown in FIG. 7 , if one block is described as an embodiment, a gas detection sensor 710 is installed at a height of about 2 to 4 m above the central bulkhead 111 and the horizontal bulkhead 110 of the coal storage shed, and gas detection The sensor 121-2 has a first gas detection sensor 714L and a second gas detection sensor 714R installed at regular intervals on the left and right sides of one block of a 13m long coal mine so that the left and right intervals are within about 10m, and the coal pile The generated carbon monoxide is lighter than air and is configured to be detected in the passageway to the roof. The gas detection sensors 714L and 714R include a sensing unit 714-1 for sensing gas and a communication unit 714-2 for transmitting the sensed data. The communication unit 714-2 transmits sensed data using wireless or wired communication.

When carbon monoxide (CO) is sensed, the temperature sensor 121-1 installed at a height of about 1 to 2 m from the top of the central partition wall 111 moves left and right along the moving orbit line 730 in the form of a matrix. The injection device 160 is operated according to the low-carbon ignition position arrangement 350 which is changed according to the movement of the temperature sensor 121-1. The gas detection sensor 121-2 for detecting the carbon monoxide (CO) concentration of the ignition start coal is installed in the upper part of the block in order to reduce the influence of carbon monoxide flowing in from the coal storage of the side block.

The temperature sensor 121-1 is attached to the left-rotation or right-turn movement track line 730 on the upper side, moves from the surface temperature of the coal pile on the lowest slope to the contact part of the top-side bulkhead, and then rotates left again to the original position. Measure the surface temperature while returning.

On the other hand, the coal storage block 700, the central bulkhead 111, the central bulkhead 111 for stacking coal piles as the center, the horizontal side bulkhead 110 and the inclined bottom surface 50 that descends toward the central bulkhead 111. is composed of At this time, the bottom surface 50 is configured with an inclination of about 5 ° inward to prevent the coal from going out.

The coal pile 150 is formed inside the partition walls 111 and 110 . Therefore, the area with the highest frequency of spontaneous ignition has more granulated material than the lower floor slope (G1) due to the inclined floor bulkhead, and the 1/3 point section of the slope from the lower floor slope (G1), where the updraft flows the most ( In G2), the distance between the moving track lines 730 is dense, and the distance between the moving track lines 730 is sparsely configured as the frequency of spontaneous ignition is lowered toward the normal. That is, the distance between the moving track line 730 is greater than the distance between the moving track line 730 from the lower bottom inclined surface G1 to the 1/3 point section G2 of the inclined surface as it goes further from the normal.

The inclined surface T1 from the second bundle point T2 to the central partition wall 111 constitutes a second densely spaced interval.

In other words, in the case of the moving track line 730, the moving track line 730 corresponding to the section of the first inclined surface G1 on the lower floor and the second inclined surface G2 connected to the first inclined surface G1. Intervals between a plurality of transverse lines constituting the first line pattern of are formed to decrease toward the end section of the second inclined surface G2, and the third inclined surface G3 and the third inclined surface G3 connected from the second inclined surface G2 and the second inclined surface G2 3 The interval between a plurality of transverse lines forming the second line pattern of the moving track line 730 corresponding to the section of the fourth inclined surface G4 connected from the third inclined surface G3 is the end section of the fourth inclined surface G4. increases towards Of course, the line pattern is composed of longitudinal lines and transverse lines.

In addition, the moving track line corresponding to the section between the first top surface T2 starting from the top of the coal pile 150 connected to the fourth inclined surface G4 and the contact surface T1 reaching the central bulkhead 111 . The spacing between the plurality of transverse lines constituting the third line pattern of 730 is decreased toward the end section of the contact surface T1.

FIG. 8 is a plan view of FIG. 7 . Referring to FIG. 8 , it is composed of first and second gas detection sensors 741L and 741R attached to the upper side in height by overlapping with the moving position of the upper coal storage unit of the coal pile 150 . Inside the central bulkhead 111 and the transverse bulkhead 110 , a moving orbit line 730 is installed in a matrix form on the upper side of the coal pile 150 .

The arrangement of the temperature sensor 121-1 attached to the moving track line 730 is changed to five positions according to the positions of the moving inclined surfaces G1, G2, G3, G4, and T1. The arrangement of the temperature sensor 121-1 is the first inclined surface G1, the second inclined surface G2, the third inclined surface G3, the fourth inclined surface G4, at the bottom of the coal pile 150, on the top side. The top surface (T2), which is located on the contact surface (T1) overlapping the coal storage outlet, may be omitted because spontaneous ignition hardly occurs.

The temperature sensor 121-1 includes a wheel (not shown) to move along the moving track line 730, a motor (not shown) rotating the wheel, a control circuit (not shown) for controlling the motor (not shown), etc. It may be composed of Of course, the control circuit may include a wired/wireless communication circuit.

The fire extinguishing water spray nozzle 330 rotates according to the low carbon ignition position arrangement (a, b, c, d, e, f) for each inclined surface of the temperature sensor 121-1), and when the temperature is about 100° C. or higher In response to signals from the communication device 301 and the central control terminal 310 , the extinguishing fluid driving pump 320 and the extinguishing fluid spraying nozzle 330 are operated. On the other hand, the movement orbit line 730 of the temperature sensor 121-1 has a dense interval from the lower bottom slope G1 with the highest ignition frequency to the 1/3 point section G2 of the slope, and the spontaneous ignition frequency is low. The further away from the normal, the more sparsely constructed.

The contact surface T1 from the top portion T2, which is the second bundle point, to the central partition wall 111 is configured with a second dense spacing.

In the case of the moving trajectory line 730, more strictly defined, the lines G1-1 and G1-2 are formed on the first inclined surface G1, and G2-1, G2-2, G2-1, G2-2, The line of G2-3 is constituted, the line of G3-1 is constituted on the third inclined surface G3, the line of G4-1 is constituted on the fourth inclined surface G4, and the line of T2-1 is constituted on the top surface T2. Lines are formed, and lines of T1-1 and T1-2 are formed on the contact surface T1.

9 is a driving concept of the fire extinguishing water injector 160 according to the movement arrangement of the temperature sensor 121-1 according to an embodiment of the present invention. Referring to FIG. 9 , the injection nozzle 501 of the injection nozzle machine is configured to rotate according to the low carbon ignition position arrangement (a, b, c, d, e, f, g) 350, and is divided based on the ground surface. It is configured to adjust the angle of inclination (5 ~ 60°). That is, the injection nozzle unit 330 moves left and right with a focus on the low-carbon ignition position arrangement (a, b, c, d, e, fg), and moves to the left and right positions of the injection nozzle 501 (910a, 910b, 910c, 910d, 910e, 910f, 910g).

When spraying from the bottom of the slope to the 1/3 point (G2) of the slope based on the ground surface where spontaneous ignition occurs at a frequency of 70 to 90%, the slope of the injection angle is about 5 to 20°, and the frequency of occurrence is 10 to 30%. For the injection of the contact surface (T1) section of the normal central bulkhead 111 of In order to spray from the point to the top (G4), it is configured to adjust the inclination of 30 to 45°.

It is configured to adjust the inclination and/or diffraction angle of the nozzle according to the detected coal position arrangement and/or the coal surface temperature. On the other hand, the movement trajectory line 730 of the temperature sensor 121-1 is the interval (G1 to 2, G2-1, G2) of the third point of the slope from the slope (G1) of the lower floor having the highest firing frequency. G2-2, G2~3) are densely configured and sparsely different as they move away from the top where the spontaneous ignition frequency is lowered, and the contact surface (T1) from the top surface (T2), which is the second bundle point, to the central partition wall (111). constitutes the second densely temperature sensor interval (T1 to 2, T1).

10 is a cross-sectional view of an indoor coal storage bulkhead and an actual coal pile 150 according to an embodiment of the present invention. Referring to FIG. 10 , the coal pile 150 unloads coal from the coal coal miner ( 120 in FIG. 1 ) moving in the upper part of the inner T2 of the coal coal block ( 700 in FIG. 7 ), so a top plane part is formed and the outside At (G1), a large inclined surface is formed, and a small inclined surface T1 is formed between the central partition walls 111 .

In the case of coal that is expected to spontaneously ignite, during the coal storage process, the coarse powder is accumulated at the bottom and the fine powder is piled up at the top. 70~90% (1010) of spontaneous ignition at 1/3 point (G2) from 1020) is occurring.

In the case of the bottom (G1) of the coal pile 150, the bottom surface inclined while descending toward the central bulkhead 111 serves to block the upward airflow, and from the bottom (G1) to 1/3 point rather than the bottom (G1). It is confirmed that the frequency of spontaneous ignition is high because oxygen flows into the inside of the rising slope G2 of the

On the other hand, the particle size distribution of the lower floor and the first slope (G1) is 52.5 to 25.8 mm, the particle size distribution of the slope (G2) to the 1/3 point of the lower floor slope is 41.8 to 18.8 mm, and the particle size distribution of the third slope (G3) is is 19.0~4.3mm, the particle size distribution of the 4th slope (G4) is 4.5~2.5mm, the particle size distribution of the top (T2) is 3.2~2.4mm, and the particle size of the normal slope (T1) between the top and the central partition wall (111) The distribution is characterized by stacking 3.2 to 33.2 mm, and the bottom surface (G1) is the most granulated part, whereas the bottom of the structure is inclined upward as shown in FIGS. and the second slope (G2) section, so that spontaneous ignition of the slope (G2) of the second section occurs best.

In general, the ignition index grade for each coal is calculated according to the relationship between temperature and spontaneous heat generation. This is shown in a table as follows.

Rank spontaneous heat T ¹⁸⁰ SCI A Fever difficulty >115 <2 B usually 85-115 2-4 C caution 70-85 4-8 D danger 50-70 8-20 E fever in a short time <50 >20

The following Spontaneous Combustion Index (SCI) can be obtained as a predictive index for the correlation with coal properties.

The following table shows the calorific value of real coal, industrial analysis, and elemental analysis results.

Therefore, when converted into an SCI index, 20 or more corresponds to a short-term fever, 8-20 is dangerous, and 2 or less corresponds to a difficult bullet type. Here, HHV is High Heating Value, M is moisture, FC is fixed carbon, VM is volatile matter, and Ash is ash.

<Example 1> (Evaluation of optimal fire extinguishing properties for ignited carbon)

Sub-bituminous SM coal imported from Indonesia, which is known as the coal with the highest frequency of spontaneous combustion, was used as the target coal. As shown in [Table 1], SM coal has a very high volatile content of 44.17%, and the oxygen concentration, which is a component of the oxygen functional group, is 21.54%, which is a component of elemental analysis, which causes ignition.

Coal is the most common.

The detailed specifications for each facility are as follows.

○ Coal outlet: 1m in diameter

○ Coal outlet: unloading capacity 100 ton/hr

○ Calcium carbonate tank capacity: 1,000 tons

○ Calcium carbonate concentration: 1.0∼11.0 mgCaCO3/1L H ₂ O

○ Infrared temperature measuring device: Maximum sensing temperature 400℃

○ Fire extinguishing fluid pump: Maximum discharge pressure 13kgf/㎠ (for variable damper)

○ Nozzle: Throat diameter 5cm

○ Liquid-to-liquid ratio: 0.01∼0.08ℓ fire extinguishing water/kg Hatan coal

Calcium carbonate (CaCO ₃ ) has a very low solubility in water at room temperature of 15.0 mgCaCO ₃ /1L H ₂ O or less. At the initial maximum temperature of 136°C, the ignited coal is cooled and extinguished by changing the concentration of the calcium carbonate extinguishing solution in the range of 1.0 to 11.0mgCaCO ₃ /1L H ₂ O at each interval of 10 mgCaCO ₃ /1L H ₂ O at the coal, injection pressure of 7 kgf/㎠. The results of measuring the effect are shown in the table below. As shown in the table below, when the calcium carbonate concentration is increased to 11.0 mgCaCO ₃ /1L H2O, the ignition initiator with a surface temperature of 136 ° C or higher is cooled to 45 ° C. As the concentration of calcium carbonate increases, the cooling fire extinguishing efficiency increases. It is confirmed that the optimum concentration of calcium carbonate as an extinguishing agent for ignited carbon is 3.0 to 9.0 mgCaCO ₃ /1L H ₂ O, which is a very low concentration range, for cooling and extinguishing up to the target range of 65°C.

The standard is 7kgf/cm ₂ .

The table below and FIG. 9 are the temperature changes of the fire extinguishing coals for each pressure of the fire extinguishing agent injection nozzle. The optimal concentration of calcium carbonate is 5mg CaCO ₃ /1L H ₂ O Fire water is set at a nozzle inclination of 20°, and the amount of coal is constant. It is the result of measuring the temperature change of the coal surface. As an experimental result according to the pressure of the driving pump according to the driving of the injection nozzle while lowering coal at 136℃ The temperature was cooled to less than 60℃, and the temperature was cooled up to a pressure of 10kgf/cm2 (0.08ℓ digested water/kg hatan coal), whereas it was found that the cooling rate became constant above 12kgf/cm2.

The standard is 5.0 mgCaCO ₃ /1L H ₂ O.

As such, the surface of the coal is hydrophobic, so it was found that the hydrophobicity was overcome in the calcium carbonate digested water in the pressure range of 9-11 kg/cm 2 , and the cooling and fire extinguishing effect was high through improved wettability. That is, as the injection pressure increases, the amount of sucked fire water increases and the liquid level ratio, which is the amount of fire extinguishing water compared to the coal amount of coal, also changes.

The change of the fire extinguishing liquid injection amount ratio (liquid height ratio) to the amount of coal for each fire extinguishing agent injection nozzle pressure is shown in FIG. 12 . The liquid-to-liquid ratio of 0.056 to 0.08ℓ fire extinguishing water/kg coal amount was found in the pressure range of 9-11kgf/cm2, which is the optimum fire extinguishing efficiency when the injection nozzle is operated. The length to reach the slope by spraying fire extinguishing water at intervals of 10° with a nozzle inclination of 5 to 60° in the upper vertical direction at a spray pressure of 9 and 11 kg/cm2 based on the ground surface is 2.0 to 2.5 m in height of the slope as shown in FIG. 13 , 4.6-5.2 m, 8.0-8.5 m. The sections are 12 to 14 m, 15.0 to 16 m, 18.5 to 19.0, and 20 to 20.5 m. Therefore, from the lower floor where spontaneous ignition occurs most frequently, it is driven at a normal inclination of 5 to 20°, and in the case of the contact surface T1 of the uppermost central partition wall 111 where the second spontaneous ignition occurs most, the nozzle slope is 50 to It is suitable for operation at 60°. On the other hand, it can be seen that the lower the nozzle inclination of 5 to 20°, the more coal at a position of 3.0 to 7.0 m, which is a position close to the floor, is cooled and extinguished by cooling.

It can be seen that the higher the slope, the lower the temperature of the coal accumulated in the upper part because it is sprayed on the upper coal. An embodiment of the present invention is for selectively cooling and extinguishing coal only in a portion where ignition occurs when storing coal.

<Example 2> ( Spontaneous ignition site detection and digestion characteristics evaluation )

In the case of Example 2, the size of the indoor coal pile is 10,600 m 2 of the coal pile surface area (based on 100,000 tons), 10,000 m ² on the sides, 600 m ₂ on the front and back sides, ₁₂ mH x 20 mW x 200 mL x both sides, and an apparent density of 0.8 ton/m ³ to be. In Example 2, one module 12mH x 16mW x 13m L section was used as the real section as shown in FIG. As shown in FIGS. 1 and 7, coal piles 150 were piled up as shown in FIGS. 1 and 7 while storing Indonesia SM coal, which is a spontaneously ignited cluster coal, and the left and right carbon monoxide concentrations were detected using a carbon monoxide (CO) concentration meter for each low coal period, and the carbon monoxide concentration was When detected, the surface temperature of the coal was measured while moving by the slope and left and right sections using a mobile infrared temperature measuring device, and it was configured to be automatically cooled and extinguished at the location where the ignition occurred.

The infrared temperature sensor is located on the inner upper side of the central partition wall 111 and the horizontal partition wall 110 at the moving positions (G1, G1~2, G2-1, G2-2, G2~3, G3, G4, T1) of the infrared measuring device. ∼2, T1), the arrangement is changed to 9 positions, so depending on the arrangement of the infrared thermometer, the bottom of the coal pile slope (G1), the second position (G2), the third position (G3), the four slopes The second position (G3 to G4), the fifth position on the slope (the bulkhead contact surface (T1) beyond the top, and the normal flat part (the section between T1 to G4) overlapping the coal storage outlet) were omitted because spontaneous ignition hardly occurred. The temperature sensor for measuring the internal temperature of the 50 cm depth of the coal pile 150, which is the point where the ignition occurs, is located at 1.5, 4.5, 7.5m, 10m, 12m and 19.0m positions from the floor based on the slope as shown in FIGS. 9 and 14. A t-type temperature sensor was installed, and it was installed on the whole of one convex at an interval of 3 m on the left and right.

On the other hand, the depth of the temperature sensor was installed at 0.5 m, which is the depth at which spontaneous ignition starts. The temperature sensor is t-type and can measure up to 400℃, and the data logger is configured to store data for 8 days at 1-minute intervals. Temperature data was acquired at weekly intervals and performed by rebooting.

11 is a graph showing the temperature change of the ignition-generated ignited coals according to the pressure of the extinguishing agent injection nozzle according to an embodiment of the present invention. Referring to FIG. 11 , since coal is hydrophobic of an oil component, the fire is not turned off at all when a hydrophilic fire extinguishing liquid is sprayed. Therefore, it is necessary to apply a physical contact force by adding more than a certain pressure depending on the fire extinguishing water used. In order to extinguish the ignition site of the contact surface (T1), where Indonesia SM coal was stored for one week and spontaneously ignited at a surface temperature of 136 ° C, 5 mg CaCO ₃ /1L H ₂ O fire extinguishing water was sprayed on the upper vertical axis based on the ground surface at an inclination of 55°. The hydrophobicity of the coal surface from the time of operation at 7kgf/cm2 (0.045ℓ extinguishing water/kg Hatan coal) with the pressure of the driving pump (2-5) in order to keep the coal surface temperature at a constant level and to extinguish the coal surface at 25℃ or less. It was found that the cooling effect was high by physically overcoming the

12 is a graph showing a change in the amount of fire extinguishing liquid injection amount (liquid height ratio) compared to the amount of stored ignition carbon for each pressure of the fire extinguishing agent injection nozzle according to an embodiment of the present invention. Referring to FIG. 12 , the liquid-to-liquid ratio of 0.045 to 0.08 L fire extinguishing water/kg hatan coal was found in the optimum fire extinguishing efficiency pressure range of 8-11 kgf/cm 2 when the injection nozzle was operated.

13 is a view showing the measurement of the spray length for each inclination of the fire extinguishing water spray nozzle according to an embodiment of the present invention. Referring to FIG. 13, at a spray pressure of 9 and 12 kg/cm ² based on the ground surface, the height of the slope is the length to reach the slope by spraying fire extinguishing water at intervals of 10° with a nozzle inclination of 5 to 60° in the upper vertical direction, respectively. 2.0-2.5 m, 4.6-5.2 m, 8.0-8.5 m. The sections are 12 to 14 m, 15.0 to 16 m, 18.5 to 19.0, and 20 to 20.5 m.

Accordingly, from the lower floor, where spontaneous ignition occurs most frequently, the vehicle is driven at a slope of 5 to 20° in general from the lower floor, where spontaneous ignition occurs most frequently, and in the case of the contact surface T1 of the uppermost central partition wall 111 where the second spontaneous ignition occurs most, the nozzle slope is 50 to It is suitable for operation at 60°. On the other hand, it can be seen that the lower the nozzle inclination of 5 to 20°, the colder and extinguished coal at a position of 3.0 to 7.0 m, which is a position close to the floor as granulated powder. It can be seen that the higher the slope, the lower the temperature of the coal accumulated on the upper side because it is sprayed on the upper side of the coal. Example 2 is for selectively cooling and extinguishing coal only in the portion where ignition occurs when storing coal.

14 is a diagram illustrating the installation of a temperature change measuring sensor after unloading of a coal pit ignited coal according to an embodiment of the present invention. Referring to FIG. 14 , it is an installation view of temperature sensors 1410 to 1490 for measuring a temperature change of a depth of 50 cm according to the height of each slope after unloading SM bullets, which are expected to cause spontaneous ignition. The temperature sensor is configured to measure the temperature below 400°C in real-time at 0.1°C intervals. It was installed on the inclined surface in contact with the central bulkhead 111, that is, 19.0 m in length. The left and right width intervals were installed at 3.0 m.

Since the arrangement of the temperature sensor is changed to 5 positions according to the moving positions (G1, G2, G3, G4, T1) of the infrared measuring device on the inner upper side of the central partition 111 and the horizontal partition 110, the infrared temperature measuring device According to the arrangement of the coal pile, the slope bottom part (G1), the second position of the slope (G2), the third position of the slope (G3), the fourth position of the slope (G3~G4), the fifth position of the slope (the bulkhead contact surface beyond the top side ( T1), the normal flat portion (the section between T1 and G4) overlapping the outlet of the coal storage unit 120 may be omitted because spontaneous ignition hardly occurs.

15 is a table showing changes in temperature for each storage period and location according to an embodiment of the present invention. 15, the coal storage period (days), the length of the slope, and the temperature change (°C) for each coal storage period are shown.

16 is a table showing a 50 cm depth temperature sensor, an infrared surface temperature change, and a carbon monoxide concentration change according to an embodiment of the present invention. Referring to FIG. 16 , it shows the storage time (days), the inclined plane orientation coefficient (TC: Texture Coefficient), and the infrared temperature (°C).

17 is a graph showing the results of measuring the internal temperature at a depth of 50 cm for each slope for each period of expected spontaneous combustion coal storage according to an embodiment of the present invention. Referring to FIGS. 15 and 17 , the average temperature of a temperature sensor with a depth of 50 cm for each slope installed after unloading Indonesian SM bullets, which are spontaneously igniting multiple bullets, was found to be high in the order of slope 4.5m>19.0m>7.5m>12m>10m. In particular, in the case of the 4.5 m section (G2), spontaneous ignition occurred 8 days after unloading, and in the case of the contact surface (T1) of the central bulkhead 111 at 19.0 m, spontaneous ignition occurred 12 days after unloading. .

On the other hand, in the case of the 4.5m (G2) section, the nozzle inclination was 10 to 15° and the injection pressure was 9 kg/cm ² , and in the 16.5 m (T1) section, the nozzle inclination was 50 to 55° and the injection pressure was 10 kg/cm ² . After cooling and extinguishing, the internal temperature was maintained below 50°C.

18 is a graph showing a comparison value between a result of measuring a temperature of 50 cm in depth of a spontaneous ignition section with a t-type sensor and a surface temperature sensed by a mobile infrared measuring device according to an embodiment of the present invention. 16 and 18, after unloading Indonesian SM bullets, which are spontaneously igniting multiple bullets, 8 and 12 days after unloading, a temperature sensor with a depth of 50 cm in the 4.5 m and 19.0 m sections of the slope where spontaneous ignition occurred and the moving infrared measurement results were shown. This is the comparative experimental result.

In the case of the 4.5m section (G2), the internal temperature at a depth of 50 cm was higher than the surface temperature until spontaneous ignition occurred 8 days after unloading, whereas spontaneous ignition started in earnest after 8 days and carbon monoxide and carbon dioxide were released Infrared temperature sensor on the same day

The surface temperature of the coal measured with . was higher than the internal temperature at a depth of 50 cm, indicating that spontaneous combustion was diffused from the inside to the surface. The same trend was also observed in the case of a slope of 16.5 m.

On the other hand, in the case of the 4.5m (G2) section of the slope, the surface temperature of 185℃ was cooled to 30℃ by spraying with a nozzle inclination of 10-15° and a spraying pressure of 9kg/cm2 on the day of spontaneous ignition (8 days after unloading), and 19.0m ( In the case of section 2-2T1), the surface temperature was maintained below 40 by cooling and extinguishing the surface temperature of 176°C to the surface temperature of 24°C by spraying with a nozzle inclination of 50 to 55° and an injection pressure of 10 kg/cm2.

19 is a graph showing the change in the CO concentration for each period of coal storage after unloading of spontaneously ignited coal according to an embodiment of the present invention. 16 and 19, after unloading Indonesian SM bullets, which are spontaneously igniting multiple bullets, 8 and 12 days after unloading, a temperature sensor with a depth of 50 cm and a movable infrared measurement result in the 4.5 m and 19.0 m sections of the slope where spontaneous ignition occurred This is the comparative experimental result.

In the case of the 4.5 m section (G2), the internal temperature at a depth of 50 cm was higher than the surface temperature until spontaneous ignition occurred 8 days after unloading, whereas spontaneous ignition started in earnest after 8 days and carbon monoxide and carbon dioxide were released. On the same day, the surface temperature of the coal measured by the infrared temperature sensor was higher than the internal temperature at a depth of 50 cm, indicating that spontaneous combustion spreads from the inside to the surface. On the other hand, in the case of the 4.5m (G2) section of the slope, the surface temperature of 185℃ was cooled to 30℃ by spraying with a nozzle inclination of 10-15° and a spraying pressure of 9kg/cm2 on the day of spontaneous ignition (8 days after unloading), and 19.0m ( In the case of section T1), the surface temperature was maintained below 40 by cooling and extinguishing the surface temperature of 176°C to the surface temperature of 24°C by spraying with a nozzle inclination of 50 to 55° and an injection pressure of 10 kg/cm2.

3~9mg CaCO ₃ /1.0 ℓ H ₂ O Calcium bicarbonate (Ca(HCO ₃ ) ₂ ) is formed through the endothermic reaction with the flue gas (CO, CO ₂ ) and surface-generated heat of the ignited coal using the fire extinguishing liquid, and By saponification reaction with oil ((HO-CO-CH ₂ ) _n ), a coating film of calcium salt ((Ca-(O-CO-CH ₂ ) ₂ ) can be formed on the coal surface to prevent contact with external oxygen.

In addition, the fire extinguishing liquid supplied at a pressure of 8-11kgf/cm2 is sprayed with a nozzle inclined 5-20° vertically from the top of the ground, and the upper 1/3 point (G2) of the inclined surface is removed from the floor where the ignition frequency is 70-90%. The fire is extinguished by cooling, and the ignition position (T1) from the top of the 10-30% ignition frequency to the contact slope of the central bulkhead 111 is selectively cooled and extinguished through the nozzle injection that is inclined 50-60° vertically from the top of the ground. Cool and extinguish the coal surface temperature of 100~250℃ to 25℃ or less.

Lastly, the calcium carbonate fire extinguishing water spray nozzle adjusts the nozzle position and inclination according to the arrangement of the movable red line temperature measuring device and the location of the ignition occurrence. The method allows for effective spontaneous ignition detection and control of spontaneous ignition through cooling fire extinguishing.

In addition, the steps of the method or algorithm described in connection with the embodiments disclosed herein are implemented in the form of program instructions that can be executed through various computer means such as a microprocessor, a processor, a CPU (Central Processing Unit), etc. It can be recorded on any available medium. The computer-readable medium may include program (instructions) codes, data files, data structures, and the like alone or in combination.

The program (instructions) code recorded on the medium may be specially designed and configured for the present invention, or may be known and available to those skilled in the art of computer software. Examples of the computer-readable recording medium include magnetic media such as hard disks, floppy disks and magnetic tapes, optical media such as CD-ROMs, DVDs, Blu-rays, and the like, and ROM, RAM ( A semiconductor memory device specially configured to store and execute program (instruction) code such as RAM), flash memory, and the like may be included.

Here, examples of the program (instruction) code include not only machine language codes such as those generated by a compiler but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

110: transverse bulkhead 111: central bulkhead
120: low carbon 121: measuring system
121-1: temperature sensor 121-2: gas detection sensor
150: coal block 160: injection device
300: indoor coal storage spontaneous ignition detection system
301: communication device
310: central control terminal
320: drive pump
330: spray nozzle
340: digestive fluid supply
350: low-projection firing position arrangement
730: moving orbit line
741L: first gas detection sensor 741R: second gas detection sensor
G1 to G4: first to fourth inclined surfaces
T1: contact surface T2: top surface

Claims (15)

A measuring system that detects temperature information and gas information in order to detect the spontaneous ignition state of the coal pile 150 stored in the coal storage block 700 divided by the central bulkhead 111 and the horizontal bulkhead 110 in the indoor type coal yard ( 121);
Using the temperature information and the gas information, a low carbon ignition position arrangement 350 in which the spontaneous ignition state occurs is calculated, and spraying control of the extinguishing liquid for removing the spontaneous ignition state according to the low carbon ignition position arrangement 350 a central control terminal 310 for generating commands; and
a spraying device 160 for spraying the extinguishing liquid to one location (a, b, c, d, e, f) of the low carbon ignition location array 350 according to the spray control command;
Indoor coal storage spontaneous ignition detection system comprising a.
The method of claim 1,
The measuring system 121 is
a gas detection sensor 121-2 for detecting the gas information from a predetermined surface depth of the coal pile 150; and
A temperature sensor 121-1 that detects the temperature information from the surface of the coal pile 150 while moving along a moving orbit line 730 set in advance as the gas information is detected; includes, the temperature sensor The indoor coal storage spontaneous ignition detection system, characterized in that the arrangement of the low coal ignition position (350) is changed according to the movement of (121-1).
3. The method of claim 2,
The gas detection sensor 121-2 includes a first gas detection sensor 741L and a second gas having a predetermined height from the upper portions of the central partition wall 111 and the horizontal partition wall 110 and installed at a predetermined distance from each other. Indoor coal storage spontaneous ignition detection system, characterized in that consisting of a detection sensor (741R).
3. The method of claim 2,
The moving track line 730 is a first of the moving track line 730 corresponding to a section between the first inclined surface G1 on the lower floor and the second inclined surface G2 connected to the first inclined surface G1. line pattern;
An indoor coal storage spontaneous ignition detection system, characterized in that the interval between the horizontal lines constituting the first line pattern decreases from the first inclined surface (G1) to the end section of the second inclined surface (G2).
5. The method of claim 4,
The movement trajectory line 730 corresponds to the section of the third inclined surface G3 connected from the end section of the second inclined surface G2 and the fourth inclined surface G4 connected from the third inclined surface G3. a second line pattern of the orbit line 730;
The interval between the horizontal lines forming the second line pattern increases from the third inclined surface (G3) to the end section of the fourth inclined surface (G4).
6. The method of claim 5,
An indoor coal storage spontaneous ignition detection system, characterized in that from the first inclined surface (G1) to the second inclined surface (G2), the ignition frequency for the spontaneous ignition is 70 to 90%.
7. The method of claim 6,
The moving track line 730 is a section between the first top surface T2 starting from the top of the coal pile 150 connected to the fourth inclined surface G4 and the contact surface T1 reaching the central bulkhead 111 . a third line pattern of the moving orbit line 730 corresponding to ;
The interval between horizontal lines forming the third line pattern is decreased from the first top surface (T2) to the end section of the contact surface (T1).
8. The method of claim 7,
An indoor coal storage spontaneous ignition detection system, characterized in that the ignition frequency for the spontaneous ignition on the contact surface (T1) is 10 to 30%.
The method of claim 1,
The extinguishing solution is a coating film of calcium salt on the surface of the coal through a saponification reaction with oil ((HO-CO-CH ₂ ) _n ) of the coal surface of the coal pile 150 ((Ca-(O-CO-CH ₂ ) ₂ ) ) to form 3 to 9mg CaCO ₃ /1.0 ℓH ₂ O Indoor coal storage spontaneous ignition detection system, characterized in that.
The method of claim 1,
The central control terminal 310, if the temperature information is less than 50 ℃, indoor coal storage spontaneous ignition detection system, characterized in that to stop the spray control command.
(a) temperature information in order to detect the spontaneous ignition state of the coal pile 150 stored in the coal storage block 700 divided by the central bulkhead 111 and the horizontal bulkhead 110 in the indoor type coal yard by the measuring system 121 and detecting gas information;
(b) the central control terminal 310 calculates the low carbon ignition position arrangement 350 in which the spontaneous ignition occurs by using the temperature information and the gas information, and the spontaneous ignition according to the low carbon ignition position arrangement 350 generating a dispensing control command of the digestive fluid for removing the condition; and
(c) spraying, by the spraying device 160, the extinguishing liquid to one position (a, b, c, d, e, f) of the low carbon ignition position arrangement 350 according to the spray control command;
Indoor coal storage spontaneous ignition detection method comprising a.
12. The method of claim 11,
The measuring system 121 is
a gas detection sensor 121-2 for detecting the gas information from a predetermined surface depth of the coal pile 150; and
A temperature sensor 121-1 that detects the temperature information from the surface of the coal pile 150 while moving along a moving orbit line 730 set in advance as the gas information is detected; includes, the temperature sensor The method for detecting spontaneous ignition of an indoor storage coal field, characterized in that the arrangement of the low coal ignition position (350) is changed according to the movement of (121-1).
13. The method of claim 12,
The moving track line 730 is a first of the moving track line 730 corresponding to a section between the first inclined surface G1 on the lower floor and the second inclined surface G2 connected to the first inclined surface G1. line pattern;
The method for detecting spontaneous ignition of an indoor coal yard, characterized in that the interval between the horizontal lines constituting the first line pattern is decreased from the first inclined surface (G1) to the end section of the second inclined surface (G2).
14. The method of claim 13,
The movement trajectory line 730 corresponds to the section of the third inclined surface G3 connected from the end section of the second inclined surface G2 and the fourth inclined surface G4 connected from the third inclined surface G3. a second line pattern of the orbit line 730;
The method for detecting spontaneous ignition of an indoor coal yard, characterized in that the interval between the horizontal lines constituting the second line pattern increases from the third inclined surface (G3) to the end section of the fourth inclined surface (G4).
15. The method of claim 14,
The moving track line 730 is a section between the first top surface T2 starting from the top of the coal pile 150 connected to the fourth inclined surface G4 and the contact surface T1 reaching the central bulkhead 111 . a third line pattern of the moving orbit line 730 corresponding to ;
The method for detecting spontaneous ignition of an indoor coal mine, characterized in that the interval between horizontal lines constituting the third line pattern decreases from the first top surface (T2) to the end section of the contact surface (T1).

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