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Implementation Plan of Fire Extinguishing and Proposed Explosion System for Pulverized Coal System in Cement Industry

At present, there is a serious problem in the domestic cement manufacturing industry, that is, coal powder system explosion. The pulverized coal system did not explode once or twice in a row, and the second explosion was more violent than the first. After the explosion, it was accompanied by a fire. The brunt of the pulverized coal fire was a dust collector. It would seriously ignite accumulated powder if not fire-fighted. Will have more serious consequences.

    The pulverized coal system fire extinguishing function is relatively mature in the field of fire application. The pulverized coal system in the cement or power industry has been widely used, and the fire extinguishing effect is very obvious. However, the current pulverized coal system has two problems that urgently need to be solved: 1. The installation position and the number of installations of fire detectors need to be actually dealt with in practice, and it is not possible to use a detector or a setting method in a uniform manner, especially for collection. Dust fire detection should be based on its structure and temperature trend to determine the detection method. 2, fire extinguishing systems usually use high-pressure carbon dioxide or low-pressure carbon dioxide fire extinguishing system, the fire extinguishing function itself is beyond reproach, but can the carbon dioxide system with a thousandth of a second time fusion in the proposed explosion system, each designer should be more The theme of concern is, after all, the prevention of fire is what we are pursuing. Extinguishing fire is the frustration we use to prevent further disasters from expanding.

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1. How to set the temperature detector

    The temperature detector is used in the pulverized coal system and has two main functions. First, it detects whether the ambient temperature exceeds the normal production temperature to remind the staff to deal with it accordingly. Second, find out the real fire.

    In the detection of dust collectors, it is common practice to install a cable-type linear differential temperature detector, which is basically arranged around the horizontal position of the “milk shank” of the dust collector. If an explosion occurs, the detector is broken. This disposition is skeptical. In addition, the temperature and flame of the “lid” of the dust collector will spread upward after ignition, and it is more doubtful whether the side-arranged detector temperature detection speed is more effective. At present, many dust collectors use high-density and small-scale liners. If they are arranged directly above the bladder, it will cause inconvenience to the replacement of the bladder and the installation of the detector. However, if it is arranged according to the following figure, the detector detection density and detection speed There is a great advantage. In addition, the ambient temperature is detected and a temperature-sensing rod is installed at each "bucket" to detect the ambient temperature. If you use the air pipeline temperature sensor that is currently on the market and you can detect the ambient temperature, you can also play the role of a fixed temperature difference. In addition, anti-knock ability and anti-aging have their own irreplaceable functions.

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In the pulverized coal bunker temperature detector arrangement method is best placed on the top of the warehouse and the warehouse wall layout density should be appropriate, the country also has relevant specifications for reference. Not much to mention here.

    There are not many fire detection methods in the coal mill at present. Generally, only one temperature-sensing rod hole is left in the coal mill. It is more difficult to arrange linear or other detectors.

2. Design of explosion suppression system

    The explosion suppression system detects and releases inhibitors in the system equipment in the early stages of the explosion to prevent the spread and expansion of the explosion. Before designing an explosion suppression system, it is necessary to understand the characteristics of flammable substances in the operating environment; for example, the upper and lower explosion limits (LEL/UEL), the maximum explosion pressure (Pmax), the explosion index (Kst), and the maximum explosion pressure rise rate (dP/ Dt) max, material composition, etc. The concentration of flammable dust clouds is within the explosion range (upper and lower limits of explosion). Generally, the higher the degree of dispersion of dust, the greater the content of combustible gas and oxygen, the higher the intensity of fire source, the original temperature, the lower the humidity, and the lower the inert dust and ash, the greater the explosion limit range. The lower limit of explosion of general dust is 20-60g/m3, and the upper limit is 2-6kg/m3.

    Explosion suppression systems generally consist of sensors, suppressors, and controllers. Once the sensor of the suppression system senses a change in temperature and pressure in the device, it can be predicted whether an explosion will occur. The types of sensors can generally be classified into the following three types:

Boost Rate Sensor

Pressure Sensing Sensor

UV/IR Sensor

    It is generally more common in the industry as an explosion suppression system for ultraviolet or infrared sensors and boost rate sensors. The suppressor is composed of multiple inhibitor release devices. The main principle of explosion suppression is the use of the initial stage of explosion. The increase in pressure is more moderate, usually when the sensor detects the slight pressure change at this stage until the explosion is about to happen. A high-speed release valve is actuated to release the inhibitor instantaneously for a fraction of a thousandth of a second. A complete explosion suppression system is usually activated when the explosion pressure reaches 0.1 bar. Suppresses the effect of the explosion. The advantages of such a device not only prevent the device from breaking and damaging, but also limit the explosion to the device, which can avoid the impact of the explosion on the outside of the device. It can also be used as a treatment for toxic flammable materials, or there is no space on the container. Use on device vent outlets.


3, the fire extinguishing system has been relatively mature in the country, the following is part of the drawings of the past works for reference. In addition, it needs to be clarified that inerting and extinguishing is a system. If inerting, there is no fire extinguishing. According to the actual situation, the inerting and extinguishing doses can be stored separately, each with its own pharmaceuticals. It can be stored with the largest functional agent and has another function.

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Address: RM. 1103, Lihe Building, NO.59 Suli Road, Suzhou, Jiangsu, China

Tel:13862166059

Email:sales@licornechina.com

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