JP2011248646A - Fire detection system, fire detection device using the same system, and fire extinguishing method for granular metal using the same device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fire detection system for a granular metal capable of accurately detecting occurred flames and the possibility of fire breaking and also effectively extinguishing occurred live coals, a fire detecting device using the system, and a fire extinguishing method for the granular metal using the device.SOLUTION: A fire detection system includes infrared ray detection means, ultraviolet ray detection means, fire breaking determination means connected to those detection means, and alarm means. The detection means independently and severally detect infrared rays and ultraviolet rays emitted from a detection object which is continuously transferred on a transfer line. The fire breaking determination means determines presence/absence of fire breaking by analyzing a detected signal and operates an alarm device in the case the presence of fire breaking is determined by the detected signal from either of the detection means. Also a fire detection device operating the fire detection system and a fire extinguishing method for a granular metal using the fire detection device are provided.

Description

  The present invention relates to a granular metal fire detection system, a fire detection device using the system, and a method for extinguishing a granular metal in which a fire has occurred using the device.

  In the so-called crawl method, which is known as an industrial production method of titanium metal, titanium tetrachloride and molten metal magnesium are reduced in an inert gas atmosphere in a stainless steel reaction vessel heated to 900 to 1000 ° C. To produce sponge titanium.

  Molten magnesium chloride or unreacted molten metal magnesium by-produced by the reduction reaction remains in the voids of the sponge titanium produced in the reaction vessel. For this reason, the titanium sponge after the reaction is again heated to a high temperature under a reduced pressure atmosphere to evaporate the residual component in the titanium sponge, thereby separating and removing the residual component from the sponge titanium.

  Sponge titanium from which molten magnesium chloride and molten metal magnesium have been separated and removed is extracted from the reaction vessel in a lump shape, and then subjected to a crushing and pulverizing treatment step. In this step, first, the titanium sponge lump is crushed with a guillotine-type press cutter to form a sponge titanium lump, and further pulverized with a jaw crusher or the like. Then, it is sized and made into a granular product sponge titanium.

  When the sponge titanium blob is pulverized into granules by a jaw crusher or the like, it may be charged by being heated to a high temperature by frictional heat during pulverization. Therefore, a spark is generated between the granular sponge titanium, which becomes a fire type, which may develop to the combustion of the sponge titanium due to the presence of oxygen in the atmosphere, and eventually develop to a fire.

  In order to prevent such combustion and fire, in the process of crushing and crushing titanium sponge, we are striving to prevent the occurrence of fire by installing a monitoring camera in the process and constantly monitoring the generation of fire types. .

  However, the monitoring operation of the titanium sponge by the monitoring camera requires an operator to continuously monitor the monitor image constantly and requires a lot of labor, and the monitoring camera has a certain size. Until a flame or smoke is generated, the fire type cannot be determined, and it is difficult to detect a fine fire type or a fire type hidden behind another sponge titanium.

  Furthermore, even a sponge titanium having an appearance similar to that at room temperature without developing to a distinguishable fire type is heated to a high temperature of about 200 to 300 ° C. by frictional heat or the like. Titanium may ignite and cause a fire when it comes into contact with combustible materials such as resin components in the process or on the way of transfer. It is impossible to detect by observation.

  As a technique that can be applied to such a situation, a fire detection system is known in which infrared rays emitted from a high-temperature detection target are detected by an infrared sensor (see, for example, Patent Document 1). In the fire detection system disclosed in Patent Document 1 using infrared rays, the presence or absence of a fire is determined by analyzing the intensity and temporal change of infrared rays emitted from a detection object.

  However, in the method using infrared rays, the intensity and time change of the infrared rays may change depending on the type and size of the object to be detected, and it is necessary to change the setting each time. There is room for it. In addition, it is known that fire detection is difficult in a fire detection system using infrared rays when the detection target is small.

  On the other hand, there is known a fire detection system in which an ultraviolet sensor detects an ultraviolet ray caused by a fire type of a detection target or emitted sparks (see, for example, Patent Document 2). In the fire detection system disclosed in Patent Document 2 using ultraviolet rays, when the ultraviolet rays of the flame are detected for the first time, it is not determined that a fire has occurred. It is disclosed to judge. In this method, it is possible to accurately detect the occurrence of a continuous flame that can develop into a fire, without causing a single instantaneous firing or spark as a fire.

  However, in such a method using ultraviolet rays, there is no fire type, but the detection target heated to a temperature that causes a fire when it comes into contact with a flammable substance such as a resin product or paper product is heated. It is difficult to detect the condition as a potential fire. In addition, since the presence or absence of a flame or spark is detected, even if there is no fire, even if there are multiple instant sparks or fires occurring on the sponge titanium flowing in the crushing process line, it is detected as a fire. It is also known that there are many malfunctions. As described above, infrared rays and ultraviolet rays applied to fire detection have advantages and disadvantages, respectively.

  As another fire detection system, a fire detection system using both infrared rays and ultraviolet rays is also known (see, for example, Patent Document 3). The fire detection system described in Patent Document 3 is configured so that the field of view of the infrared sensor and the ultraviolet sensor overlaps the same field of view of the object to be detected, and processes the signals from the infrared sensor and the ultraviolet sensor independently. The system is configured to finally generate an alarm when the determination of the signal from both sensors is a fire.

  However, in the system of Patent Document 3, when the temperature of the sponge titanium is in an overheated state and there is a risk of fire even if no flame is generated like the sponge titanium being crushed, the infrared sensor fires. Although it is determined that a fire has occurred, the UV sensor determines that no fire has occurred because no flame has occurred. As a result, there is a risk that it may be determined that a fire does not occur comprehensively.

  As described above, the fire detection system disclosed in the patent document detects the state of sponge titanium that has many malfunctions and may cause a fire or fire. There is a need for a fire detection system that can not accurately detect the situation that can lead to the occurrence of a fire. In addition, although the conventional method can detect fires effectively, there is no disclosure of means for appropriately extinguishing or extinguishing fires, and depending on the time lag from detection of fires to fire extinguishing, There is a risk of fire spreading, and there is still room for further study. Thus, there is a demand for a fire detection and fire extinguishing system that can handle not only fire detection but also fire extinguishing in a self-contained manner.

JP 05-282570 A Japanese Patent Laid-Open No. 10-040478 JP 2006-338419 A

  The present invention can not only accurately detect the possibility of flames and fires generated on granular metal, especially on granular sponge titanium during crushing, but also effectively detects the generated fire type. It aims at providing the fire detection system which can be extinguished, the fire detection apparatus using the system, and the fire extinguishing method of the granular metal using the apparatus.

  In view of such circumstances, the present inventors have made extensive studies on the above-mentioned problems, particularly both infrared rays and ultraviolet rays, and independently detect infrared rays and ultraviolet rays emitted from granular metal flowing on the line. The detected signal is processed to determine the presence or absence of a fire, and the fire can be detected without causing a malfunction by determining whether or not a fire has occurred or its possibility based on the determination result of both. As a result, the present invention has been completed.

  That is, the fire detection system of the present invention includes infrared detection means, ultraviolet detection means, fire occurrence determination means connected to these detection means, and notification means, and the detection means is continuously provided on the transfer line. Infrared and ultraviolet rays emitted from the object to be transported automatically are detected independently, and the fire occurrence determination means analyzes the detection signal to determine the presence or absence of a fire, and detects from either detection means If it is determined that a fire has occurred in the signal, the alarm device is configured to operate.

  In the present invention, the detection object transferred on the transfer line is configured to first detect infrared rays on the upstream side of the line and then detect ultraviolet rays on the downstream side. Is a preferred embodiment.

  In this invention, it is set as the preferable aspect that a detection target object is a granular metal.

  In the present invention, even when it is determined that there is no fire by analysis of the infrared signal, when it is determined that there is a fire by detecting and analyzing the magnitude and duration of the ultraviolet signal, It is a preferred embodiment that the alarm device is configured to operate.

  The fire detection device of the present invention is a fire detection device for operating the above-described fire detection system, characterized in that infrared detection means and ultraviolet detection means are arranged in series with respect to the transfer line. It is said.

  In this invention, it is set as the preferable aspect that the hood is arrange | positioned so that the whole detection target object may be covered.

  In the present invention, the hood is provided with an infrared detection means and a window for attaching the ultraviolet detection means, and a water mist or inert gas supply nozzle is disposed inside the hood.

  Furthermore, a method for extinguishing a granular metal according to the present invention is a method for extinguishing a granular metal using the above-described fire detection device, and when a fire is detected by a fire detection system, a combustion state and / or an overheat state. In the hood, water mist or inert gas is supplied until the temperature of the granular metal in the hood decreases to room temperature.

  In this invention, it is set as the preferable aspect which reverses the transfer line in which the granular metal cooled to room temperature was mounted, and detects the temperature of the granular metal mounted in the line again.

  According to the present invention described above, it is possible to accurately detect whether or not a granular metal has fired and its possibility without malfunction due to a spark generated after the granular metal grinding process. There is an effect.

It is a schematic diagram which shows one Embodiment of the fire detection apparatus of this invention. It is a schematic diagram which shows other embodiment of the fire detection apparatus of this invention. It is a schematic diagram which shows the reduction | restoration process of this invention. It is a schematic diagram which shows the crushing process of this invention.

  The best embodiment of the present invention will be described below with reference to the drawings. In this embodiment, a preferred embodiment will be described below, taking as an example the case where the granular metal that is the detection target of the fire detection system according to the present invention is sponge titanium.

  First, the manufacturing process of the sponge titanium of the present invention will be described with reference to FIG. Titanium tetrachloride 32 is dropped on the surface of the molten metal magnesium bath 31 charged in advance in the reaction vessel 30 held in an inert gas, thereby generating sponge titanium 33 in the reaction vessel 30. As the reduction reaction of titanium tetrachloride 32 with magnesium 31 proceeds, sponge titanium 33 is deposited in the reaction vessel 30, and together with this, molten magnesium chloride 34 is produced as a by-product, and the bath in the reaction vessel 30. Level rises. Therefore, from the start of the reaction, an operation of extracting magnesium chloride by-produced by the reduction reaction of titanium tetrachloride at a predetermined time interval to the outside of the reaction vessel 30 is performed.

  By repeating the above operation, when a specified amount of sponge titanium 33 is formed inside the reaction vessel 30, the molten magnesium chloride and metal magnesium contained in the gap of the sponge titanium 33 are brought into the bottom of the reaction vessel 30 by gravity. The operation of letting it flow down and then pulling out is performed. Next, the sponge titanium 33 that has been subjected to the above treatment is kept at a high temperature and under reduced pressure, so that magnesium chloride and metal magnesium that permeate and remain in the voids of the sponge titanium 33 are vacuum separated.

  In the reaction vessel 30 after the vacuum separation operation is completed, high-purity sponge titanium is formed in a lump shape (hereinafter, referred to as “sponge titanium lump 33” in some cases). The sponge titanium lump 33 extracted from the reaction vessel 30 is cut by a crushing means 37 such as a press cutting machine in the crushing step to obtain a sponge titanium lump 36. The sponge titanium blob 36 is further pulverized in a pulverization step using a pulverizer such as a jaw crusher and then sized to obtain the granular sponge titanium 20 of the present invention shown in FIGS. be able to.

  During the pulverization step, the titanium sponge may ignite and cause a fire on the line after pulverization and further on the downstream transfer step due to friction during the pulverization of the sponge titanium. Or even if a fire does not generate | occur | produce, the sponge titanium overheated to the high temperature which contacts with a combustible material and leads to an ignition may exist. FIG. 1 shows a fire detection system S according to an embodiment of the present invention for preventing such a fire and a potential fire, and a fire detection apparatus A using the system S.

  As shown in FIG. 1, the fire detection system S of the present embodiment has an infrared detection means 10 such as a radiation thermometer having a visual field on the upstream side with respect to the detection target line, and a downstream side that does not overlap the visual field An ultraviolet ray detection means 11 having a visual field of view, a fire occurrence detection means 12 that is connected to both detection means and analyzes the input signals from both detection means to determine the presence or absence of a fire, and a fire occurrence detection means 12 connected to the fire occurrence detection means 12 It comprises an alarm means 13 for issuing an alarm when it is determined that the alarm has occurred.

  In addition, the fire detection device A of the present embodiment includes sponge titanium 20 to 23 that take various temperature states, which are fire detection objects, and a belt conveyor 14 (hereinafter simply referred to as “line”) that transfers these. And the fire detection system S having the above-described configuration installed so as to detect infrared rays and ultraviolet rays respectively at predetermined positions on the upstream side and downstream side of the belt conveyor 14.

  The sponge titanium 20 is a sponge titanium having a temperature of about room temperature that does not ignite even when it comes into contact with a combustible material, and the sponge titanium 21 has a high temperature that does not generate a flame but ignites upon contact with a combustible material. It shows the situation of overheating. However, since the sponge titanium 21 is not in an overheated state that changes color even at high temperatures, the state cannot be detected with the naked eye. Further, the titanium sponge 22 represents a situation in which a flame is generated by being overheated by the crushing process in the crushing process and reacting with the atmosphere. Further, the sponge titanium 23 is a fine sponge titanium in an ignited state, and is ignited after the high-temperature sponge titanium is pulverized into fine particles, or is formed by the collapse of the ignited sponge titanium 22.

  As shown in FIG. 1, in the present embodiment, first, upstream of the sponge titanium 20 to 23 having various temperature states that are fire detection objects transferred by the belt conveyor 14, infrared rays are first detected upstream. It is characterized in that it is configured to detect ultraviolet rays on the downstream side after detection.

  First, the temperature information of the titanium sponge detected by the upstream infrared detection means 10 or the information such as the wavelength and / or intensity of the infrared is guided to the fire occurrence determination means 12. The fire occurrence determination means 12 is preliminarily inputted with temperature information as a reference for determining whether the temperature of the detected sponge titanium is in a fire occurrence state or whether a fire has not occurred but is in a high temperature state. It is preferable to keep it. By performing the setting in advance as described above, the temperature information detected by the infrared detecting means 10 is analyzed, and the state of the titanium sponge flowing on the line is currently ignited based on the reference temperature information. There is an effect that it is possible to accurately determine whether or not there is a state that will cause a fire in the future.

  Among the titanium sponges flowing on the line, the heated granular sponge titanium 21 and the ignited granular sponge titanium 22 are detected by the infrared detection means 10, but the flame is generated but the size is small. 23 may not be detected by the infrared detection means 10.

  In that case, the infrared detection means 10 cannot detect the sponge titanium in which the flame is generated, but the ultraviolet detection means 11 disposed on the downstream side of the infrared detection means 10 effectively uses the sponge titanium. There is an effect that it can be detected.

  Furthermore, as another aspect of the titanium sponge, sparks may be generated due to collision or friction between the titanium sponges. In such a situation, the conventional ultraviolet detection means sometimes detects this as a flame and may cause a malfunction. Therefore, in the present invention, a signal having information such as the wavelength, intensity, and duration of the ultraviolet ray detected by the ultraviolet ray detection means 11 is input to the fire occurrence determination means 12 and analyzed, and the determination for the input signal is performed. By setting the fire occurrence determination means 12 in advance as a reference, it is possible to determine whether the signal is a sponge titanium spark or a fire caused.

  Specifically, for example, by analyzing the duration of the detected ultraviolet light and determining whether it is an ultraviolet signal that has continued for a certain period of time or an instantaneous signal, a flame is being generated. There is an effect that titanium sponge can be effectively detected. Alternatively, it is possible to determine the difference between the wavelength and intensity of ultraviolet rays emitted during combustion of normal sponge titanium and those during sparking.

  As described above, in the present invention, it is possible to determine whether there is a fire by determining at least one of the infrared detection means 10 and the ultraviolet detection means 11, so that the sponge titanium that has ignited and the possibility of ignition. It is prevented to miss some sponge titanium.

  If the fire occurrence detection means 12 determines that there is a fire as described above, the alarm means 13 connected to the fire occurrence detection means 12 may simply issue an alarm to the operator and take countermeasures manually. Further, it may be interlocked with a cooling / extinguishing gas or mist ejection means.

  In the present embodiment described above, the installation position of the infrared detecting means 10 is preferably arranged as upstream as possible on the belt conveyor 14. By disposing on the upstream side of the belt conveyor 14, the sponge titanium 21 in an overheated state and the sponge titanium 22 with a flame can be detected at an early stage.

  Moreover, it is preferable that the ultraviolet ray detection means 11 is disposed at a place as close as possible to the infrared ray detection means 10. The infrared detecting means 10 can detect infrared rays of the overheated sponge titanium 21 and the ignited sponge titanium 22 having a certain size, but may not be able to detect the fine sponge titanium 23 having a flame. Therefore, by arranging the ultraviolet ray detection means 11 as close as possible to the downstream side as described above, it is possible to effectively detect the ultraviolet rays of the ignited fine granular titanium sponge 23 which is avoided from the detection by the infrared ray detection means 10. There is an effect.

  Further, it is preferable that a hood 15 is provided below the infrared detecting means 10 and the ultraviolet detecting means 11 as shown in FIG. By providing the hood 15 as described above, it is possible to effectively suppress disturbance of both detection means by sunlight and illumination.

  In the embodiment having such a hood, when it is determined by the fire detection system S that a fire has occurred, the movement of the belt conveyor 14 is first stopped, and then the hood 15 covering the upper space of the sponge titanium is applied. It is preferable to supply a mist such as water or an inert gas such as argon gas from the formed nozzles 16a to 16c.

  By exposing the above-described mist atmosphere or inert gas atmosphere to sponge titanium that may cause a fire, it is possible to effectively suppress the sponge titanium fire.

  Furthermore, by appropriately selecting the flow rate of the inert gas, the temperature of the titanium sponge can be effectively cooled.

  Here, when using mist, there exists an effect that what is called general mist-like water can be used conveniently. However, in the present invention, the average particle diameter of the mist is preferably 1000 μm or less, and more preferably 500 μm or less. When the average particle diameter of the mist exceeds the upper limit, it is not preferable because the combustion of sponge titanium is made active. Therefore, the sponge titanium fire extinguishing and cooling mist used in the present invention is preferably 500 μm or less. If the particle diameter of the mist exceeds 1000 μm, the sprayed mist remains in the sponge titanium and becomes moisture, which may cause oxidation of the sponge titanium. Moreover, if it is introduced into the melting furnace in a state where moisture is contained in the sponge titanium, water vapor is suddenly generated, which may cause an accident, which is not preferable. Therefore, the size of the mist is preferably in the above range.

  It is preferable to reverse the belt conveyor 14 once after the above processing is completed. By performing the operation as described above, the cooling status and flame status of the titanium sponge cooled and suffocated by argon gas or mist are accurately grasped again by the infrared detecting means 10 and the ultraviolet detecting means 11. There is an effect that it is possible.

  As described above, by using the fire detection system according to the present invention, the fire detection device using the system, and the method for extinguishing granular metal using the device, In addition to being able to detect the occurrence of flame in advance, the fire that is occurring can be effectively extinguished.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.
[Example 1]
Using the fire detection device A shown in FIG. 1, a titanium sponge particle size of 1 to 12.5 mm was flowed on the belt conveyor 14, and the status of the titanium sponge was monitored by the infrared detection means 10 and the ultraviolet detection means 11. . In this embodiment, sponge titanium particles 21 (sample A) intentionally heated to 200 ° C., 5 mm sponge titanium 22 in a burning state (sample B), and 1 mm sponge titanium in a burning state. 23 (Sample C) was mixed in the sponge titanium particles to confirm the performance of the fire detector.

  As a result, the sponge titanium is quickly detected by the infrared detection means 10 for the sample A, the infrared detection means 10 and the ultraviolet detection means 11 for the sample B, and the ultraviolet detection means 11 for the sample C. Could be detected.

[Example 2]
In Example 1, instead of FIG. 1, using the fire detection device having the hood 15 shown in FIG. 2, the detection performance of sponge titanium in an overheated or burned state was confirmed. The sponge titanium state could be detected accurately.

  At that time, the movement of the belt conveyor 14 is stopped, and argon gas is ejected from the nozzles 16 disposed on the hood 15 disposed above the conveyor 14, so that the entire sponge titanium is brought into an inert gas atmosphere on the belt conveyor 14. Retained. After maintaining the above state for about 1 minute, the injection of argon gas was stopped, and the state of overheating combustion of sponge titanium was determined by the infrared detection means 10 and the ultraviolet detection means 11. As a result, since the existence of a high temperature region was confirmed for some sponge titanium, argon gas was blown out again to extinguish the sponge titanium. After that, when the belt conveyor 14 on which the sponge titanium was placed was rotated forward or backward, and the overheated combustion status of other areas on the belt conveyor 14 was confirmed, it was confirmed that there was no abnormality. After the sponge titanium was removed from the belt conveyor 14, the normal operation was resumed.

[Example 3]
In Example 2, except that water mist was used in place of argon gas, the sponge titanium fire was detected and the titanium sponge in a fire state was extinguished under the same conditions. As a result, in Example 2, it was confirmed that the time required for extinguishing the sponge titanium in a fire occurrence state could be extinguished in about half the time compared to Example 2.

[Comparative Example 1]
In Example 1, the situation of titanium sponge was monitored under the same conditions except that the ultraviolet ray detection means 11 was not used and only the infrared ray detection means 10 was used. As a result, the sponge titanium 22 in an overheated state was detected, but the fine sponge titanium 23 having a flame could not be detected.

[Comparative Example 2]
In Example 1, the situation of titanium sponge was monitored under the same conditions except that the infrared detection means 10 was not used and only the ultraviolet detection means 11 was used. As a result, fine sponge titanium 23 with flames was detected, but sponge titanium 22 in an overheated state could not be detected.

  The present invention can be suitably used for a metal processing process accompanied by heat generation such as a titanium sponge crushing process.

S ... Fire detection system,
A ... Fire detection device,
10: Infrared detection means (radiation thermometer),
11 ... UV detection means,
12 ... Fire occurrence determination means,
13 ... Reporting means,
14 ... belt conveyor,
15 ... food,
16a to 16c ... nozzles,
20 ... sponge titanium (granular),
21 ... Overheated granular sponge titanium,
22: Ignited granular sponge titanium,
23 ... Flamed fine titanium sponge,
30 ... reaction vessel,
31 ... Molten metal magnesium bath,
32 ... titanium tetrachloride,
33 ... sponge titanium (bulk),
34. Molten magnesium chloride bath,
35 ... temperature control means,
36 ... titanium sponge (small lump),
37: Crushing means (press cutting machine).

Claims (9)

A fire detection system comprising an infrared detection means, an ultraviolet detection means, a fire occurrence determination means connected to these detection means, and a notification means,
The detection means independently detects infrared rays and ultraviolet rays emitted from a detection object continuously transferred on a transfer line,
The fire occurrence determination means analyzes the detection signal to determine whether a fire has occurred,
A fire detection system configured to operate the alarm device when it is determined in the detection signal from any one of the detection means that a fire has occurred.   The detection object to be transferred on the transfer line is configured to first detect infrared rays on the upstream side of the line and then detect ultraviolet rays on the downstream side. The fire detection system according to claim 1.   The fire detection system according to claim 1, wherein the detection object is a granular metal.   Even if it is determined that there is no fire by analysis of infrared signals, the alarm device is activated when it is determined that there is a fire by detecting and analyzing the magnitude and duration of the ultraviolet signal. The fire detection system according to claim 1, wherein the fire detection system is configured to do so. A fire detection device for operating the fire detection system according to any one of claims 1 to 4,
The fire detection device, wherein the infrared detection means and the ultraviolet detection means are arranged in series with respect to the transfer line.   The fire detection device according to claim 5, wherein a hood is disposed so as to cover the entire detection target.   7. The hood is provided with a window for mounting the infrared detection means and the ultraviolet detection means, and a water mist or inert gas supply nozzle is disposed inside the hood. The fire detection device described in 1.   A method for extinguishing a granular metal using the fire detection device according to any one of claims 5 to 7, wherein when a fire is detected by the fire detection system, the granule is in a combustion state and / or an overheated state. A method for extinguishing a granular metal, characterized in that water mist or an inert gas is supplied into the hood until the temperature of the metallic metal is lowered to room temperature.   The granule according to claim 8, wherein the temperature of the granular metal placed on the line is detected again by reversing the transfer line on which the granular metal cooled to room temperature is placed. To extinguish metal.

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