A method for preventing and controlling high temperature in a cylindrical coal bunker

Abstract

The present invention discloses a method for preventing and controlling high temperature in a cylindrical coal bunker. By continuously extracting and analyzing gas at the top of the silo and cooperating with the detection of optical fiber temperature measurement, a prevention space is delimited according to the position of the optical fiber temperature measurement, so as to achieve more accurate monitoring of the temperature abnormal area, and injecting inert gas into the temperature abnormal area and / or the cylindrical coal bunker to prevent spontaneous combustion. The present invention utilizes continuously collecting and analyzing the components of the gas at the top of the silo to determine the oxidation situation of the coal in the whole silo; meanwhile, the method of optical fiber temperature measurement is used to monitor the temperature abnormal points near the side wall of the silo, and give early warning to the monitored temperature abnormal points or directly implement flame retardant measures.

Description

Technical Field

[0001] The present invention relates to the field of coal storage, and particularly to a method for preventing and controlling high temperature in a cylindrical coal bunker. Background Art

[0002] Coal storage forms are generally divided into stacking and storage in bins. With the increasing requirements for environmental protection, storage efficiency, coal quality, etc., the storage method of enclosed coal bunkers has gradually become the mainstream. However, there are also many problems with enclosed coal bunkers. The diameter of enclosed coal bunkers is dozens or hundreds of meters, and most coal bunker reclaiming devices are funnels. Generally speaking, the coal directly above the funnel is easier to be discharged from the funnel compared with other areas, while the coal near the coal bunker wall area is prone to form a coal stacking dead angle, and the coal in this area will spontaneously combust after long-term stacking. In the field of coal bunker temperature detection, it is relatively advanced to use optical fiber temperature measurement. However, the optical fiber temperature measurement cable has a maximum operating temperature of only 120°C, while the spontaneous combustion temperature of coal can reach more than 250°C. The optical fiber temperature measurement cable is easily damaged by the burning coal, and the optical fiber temperature measurement cable can only measure the temperature change around it. Given the very poor heat transfer efficiency of the coal body, if the heat source is far from the optical cable, when the optical cable detects the temperature change, the temperature at the heat source is likely to be out of control.

[0003] In summary, for enclosed cylindrical coal bunkers, all current prevention and control measures for high temperature and even spontaneous combustion caused by slow oxidation of coal are very passive, and it is very difficult to accurately intervene at the initial stage of high temperature. Summary of the Invention

[0004] In order to solve the problems of 1. it is very difficult to monitor and warn the high temperature generated at the coal bunker wall and the center of the silo; 2. it is very difficult to control the key areas where high temperature is generated near the coal bunker wall, the present invention provides a method for preventing and controlling high temperature in a cylindrical coal bunker.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for preventing and controlling high temperature in a cylindrical coal bunker, comprising the following steps:

[0007] Step 1: Collect the gas at the top inside the cylindrical coal bunker through a gas analysis device, analyze the change in the volume content of the gas, and evaluate the oxidation state of the coal inside the cylindrical coal bunker based on the analyzed content change;

[0008] Step 2: Arrange temperature measurement optical fibers with an adjacent distance of L near the inner wall of the cylindrical coal bunker to collect the temperature of the coal around the coal bunker wall;

[0009] Step 3: When the gas analysis device in Step 1 analyzes that the volume content of carbon monoxide continues to increase and exceeds the volume content of ethylene, fill the cylindrical coal bunker with inert gas;

[0010] Step 4: When the abnormal high-temperature data is continuously detected by the temperature-measuring optical fiber described in Step 2, insert a temperature-measuring device into the prevention space with a radius of L around the high-temperature position detected by the temperature-measuring optical fiber from the outside of the cylindrical coal bunker to monitor the temperature of the coal pile.

[0011] Step 5: When the temperature of the coal detected by the temperature-measuring device in Step 4 exceeds the set threshold temperature, inject inert gas directly into the high-temperature position from the external space of the cylindrical coal bunker and / or fill the entire cylindrical coal bunker with inert gas.

[0012] Preferably, in the implementation of Step 1, it further includes continuously extracting gas from the inner top of the cylindrical coal bunker and analyzing the volume content of carbon monoxide and the volume content of ethylene.

[0013] Preferably, in Step 2, the temperature-measuring optical fiber is arranged in a spiral vertical arrangement with a pitch of L.

[0014] Preferably, in the implementation of Step 2: The range of L is not more than 3 meters.

[0015] More preferably, the L is 2 meters.

[0016] Further, in the implementation of Step 4, when the temperature-measuring device is inserted into the high-temperature position, the temperature-measuring device penetrates through the wall of the cylindrical coal bunker, and a sealing treatment is performed at the penetration of the wall to isolate air from entering the cylindrical coal bunker.

[0017] Further, the sealing treatment includes using a colloid or a self-foaming material to seal the temperature-measuring device and the cylindrical coal bunker.

[0018] Further, in the implementation of Step 5, when it is necessary to inject inert gas into the high-temperature position, after the temperature-measuring device is withdrawn from the cylindrical coal bunker, inert gas is injected into the gap after the temperature-measuring device is withdrawn.

[0019] Compared with the prior art, the present invention has the following beneficial effects: The present invention uses continuous collection and analysis of the gas components at the top of the silo to determine the oxidation situation of the coal in the entire silo; at the same time, it uses the optical fiber temperature measurement method to monitor the abnormal temperature points near the side wall of the silo, and gives early warnings or directly implements flame retardant measures for the monitored abnormal temperature points. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the present invention.

[0021] In the figure, 1 is the abnormal point, 11 is the temperature abnormal point, 2 is the first optical fiber, 3 is the second optical fiber, 4 is the gas analysis device, 41 is the collection pipeline, 5 is the temperature-measuring device, 6 is the high-temperature position, and 7 is the prevention space. DETAILED DESCRIPTION OF THE INVENTION

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

[0023] Comparative Example 1:

[0024] As Figure 1 shown, a method for preventing and controlling high temperatures in a cylindrical coal bunker includes the following steps:

[0025] Step A: Collect the gas at the top inside the cylindrical coal bunker through a gas analysis device, analyze the change in the volume content of the gas, and evaluate the oxidation state of the coal inside the cylindrical coal bunker based on the analyzed content change; as Figure 1 shown, the gas analysis device 4 continuously extracts the gas at the top of the cylindrical coal bunker through the collection pipeline 41, and then analyzes the gas components. Specifically, the main detection index gas volume content of the collected gas is detected, such as carbon monoxide and ethylene.

[0026] It also includes the following Step B: On a computer, compare the change in the gas content analyzed by the gas analysis device 4. When the volume content of carbon monoxide continuously increases and exceeds the volume content of ethylene, immediately fill the cylindrical coal bunker with an inert gas; the inert gas includes carbon dioxide or nitrogen and other gases that do not support combustion.

[0027] The function of Comparative Example 1 is not only to prevent and detect high temperatures generated during slow oxidation near the inner wall of the cylindrical coal bunker, but also for the entire cylindrical coal bunker, such as Figure 1 the temperature anomaly point 11 located in the middle of the cylindrical coal bunker.

[0028] Example 1:

[0029] When the coal near the inner wall of the cylindrical coal bunker shows abnormal high temperature, the gas analysis device 4 collects the temperature change, and at the same time detects an abnormal temperature change on the temperature measurement optical fiber near the inner wall of the cylindrical coal bunker. When the abnormal point of the abnormal temperature is near the inner wall of the cylindrical coal bunker, as Figure 1 described, to detect the abnormal high temperature of the coal near the inner wall of the cylindrical coal bunker and implement accurate monitoring, based on Comparative Example 1, the following steps are further included. Step a: Arrange temperature measurement optical fibers with an adjacent distance of L near the inner wall of the cylindrical coal bunker to collect the temperature of the coal around the coal bunker wall; in the arrangement, the distance of L is, as Figure 1 shown in the distance between the first optical fiber 2 and the second optical fiber 3. To meet the adjacent distance of L, the arrangement method of the temperature measurement optical fiber is to arrange the temperature measurement optical fiber vertically in a spiral with a pitch of L. The pitch of the temperature measurement optical fiber can be set not to exceed 3 meters, and preferably, the pitch can be set to 2 meters.

[0030] Step b: When the temperature measurement optical fiber continuously detects abnormal high temperature data in Step a, as Figure 1At the high-temperature position 6 detected by the temperature-measuring optical fiber, a temperature change is first detected. With the high-temperature position 6 as the center and L as the radius, a prevention space 7 is delimited. A temperature-measuring device 5 is inserted into the delimited prevention space 7 from the outside of the cylindrical coal bunker for temperature monitoring. The temperature of the prevention space 7 is monitored in real time by the temperature-measuring device 5, and the temperature-measuring device 5 can be a probe rod with a temperature sensor. In the implementation of this step b, when the temperature-measuring device 5 is inserted to the high-temperature position 6, the temperature-measuring device 5 penetrates through the wall of the cylindrical coal bunker, and a sealing treatment is performed at the penetration of the wall to isolate air from entering the cylindrical coal bunker. The specific isolation method can be: using a colloid or self-foaming agent to seal the temperature-measuring device 5 and the cylindrical coal bunker. The self-foaming agent can be flame-retardant polyurethane or other foams with foaming and flame-retardant effects.

[0031] Step c: When the temperature-measuring device 5 in step b detects a temperature exceeding the set threshold, inert gas is directly injected into the prevention space 7 determined in step b from the external space of the cylindrical coal bunker and / or the entire cylindrical coal bunker is filled with inert gas. When injecting inert gas into the prevention space 7, the inert gas can be injected through the through-hole left on the upper part of the cylindrical coal bunker after the temperature-measuring device 5 is withdrawn, that is, the inert gas is injected through the gap after the temperature-measuring device 5 is withdrawn. Since the inert gas will quickly diffuse in the prevention space 7, the oxygen content in the environment of the prevention space 7 can be quickly changed. Injecting inert gas by this method has the advantage of quick effect and can be used to prevent spontaneous combustion in case of emergency.

[0032] From Comparative Example 1, it can be seen that Comparative Example 1 can only detect the overall oxidation state of the cylindrical coal bunker, but there is no way to locate more accurately. When high temperature is generated by oxidation near the coal wall, compared with Comparative Example 1, Example 1 is provided with an optical fiber temperature measurement system, which can detect the high temperature generated by the slow oxidation of the coal in the cylindrical coal bunker. For the high-temperature area of coal oxidation found near the coal wall, the temperature-measuring device 5 is directly inserted from the coal bunker wall into the high-temperature area of the coal to achieve monitoring. And when the monitored temperature continues to rise, inert gas can also be directly injected into this place to achieve rapid flame retardancy, or the entire coal bunker can be filled with inert gas to achieve the prevention and treatment of coal spontaneous combustion. On the contrary, if the optical fiber temperature measurement does not detect a temperature change, and the gas analysis device collects and analyzes that the coal pile is in an oxidation high-temperature state, it means that the oxidation high-temperature area is in the central area of the coal bunker. At this time, it is necessary to inject inert gas for timely intervention.

[0033] The present invention has been described based on the embodiments and variants, but the embodiments in the above aspects are for facilitating the understanding of the examples of the present invention and do not limit the present invention. Any deformation, improvement, equivalent substitution, etc. made within the spirit and principle of the present invention and within the scope of the claims should be included in the protection scope of the present invention. In addition, if its technical features are not described as indispensable in this specification, they can be appropriately deleted.

Claims

1. A method for preventing and controlling high temperature in a cylindrical coal bunker, characterized in that, It includes the following steps: Step 1: Collect the gas at the top inside the cylindrical coal bunker through a gas analysis device, analyze the change in the volume content of the gas, and evaluate the oxidation state of the coal in the cylindrical coal bunker based on the analyzed content change; Step 2: Arrange temperature-measuring optical fibers with an adjacent distance of L near the inner wall of the cylindrical coal bunker to collect the temperature of the coal around the coal bunker wall; Step 3: When the gas analysis device in Step 1 analyzes that the volume content of carbon monoxide continues to increase and exceeds the volume content of ethylene, fill the cylindrical coal bunker with inert gas; Step 4: When the temperature-measuring optical fibers in Step 2 continuously detect abnormal high-temperature data, insert a temperature-measuring device into the prevention space with a radius of L around the high-temperature position measured by the temperature-measuring optical fibers from outside the cylindrical coal bunker to monitor the coal pile temperature; when the temperature-measuring device reaches the high-temperature position, the temperature-measuring device penetrates through the wall of the cylindrical coal bunker, and seal the penetration of the bunker wall to prevent air from entering the cylindrical coal bunker; the sealing treatment includes: using a colloid or self-foaming material to seal the temperature-measuring device and the cylindrical coal bunker; Step 5: When the temperature-measuring device in Step 4 detects that the coal temperature exceeds the set threshold temperature, directly inject inert gas from the external space of the cylindrical coal bunker to the high-temperature position; when it is necessary to inject inert gas into the high-temperature position, first withdraw the temperature-measuring device from the cylindrical coal bunker, and then inject inert gas through the gap after the temperature-measuring device is withdrawn.

2. The high-temperature prevention and control method for the cylindrical coal bunker according to claim 1, characterized in that, In the implementation of Step 1, it further includes: continuously extracting gas at the top inside the cylindrical coal bunker and analyzing the volume content of carbon monoxide and the volume content of ethylene.

3. The method for preventing and controlling high temperature in the cylindrical coal bunker according to claim 1, characterized in that, In Step 2, the temperature-measuring optical fibers are arranged in a vertical spiral with a pitch of L.

4. The method for preventing and controlling high temperature in a cylindrical coal bunker according to claim 1 or 3, characterized in that In the implementation of Step 2: The range of L is not more than 3 meters.

5. The method for preventing and controlling high temperature in the cylindrical coal bunker according to claim 4, characterized in that, The L is 2 meters.

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