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Safety knowledge of trichlorosilane, physical and chemical properties and production principles. Trichlorosilane, also known as trichlorosilane and silicon chloroform, is the most basic monomer in organosilane coupling agents and a raw material for the production of semiconductor silicon and single crystal silicon. With the development of the organosilane coupling agent industry, the demand for trichlorosilane is increasing. Trichlorosilane is produced from silicon powder and hydrogen chloride gas in a fluidized bed reactor. It is a colorless liquid, easily volatile and deliquescent, decomposes when exposed to water, and is soluble in organic solvents such as benzene and ether. Trichlorosilane is a first-class flammable substance when exposed to moisture. It is flammable and explosive. It reacts with water to produce hydrogen chloride gas. ； It can react strongly with oxidants and may burn or explode when exposed to open flames or high heat. Fire Hazard Analysis: The raw materials for producing trichlorosilane are all non-combustible substances, but the products during its production process are mostly flammable and explosive substances, such as hydrogen, chlorine, etc. The production of trichlorosilane requires electrolysis of salt water. Fire hazards in this process include the strong current flowing during electrolysis, which can easily cause sparks if the electrical insulation is poor. ； Hydrogen leaks often occur in electrolytic workshops, which can cause combustion or explosion when encountering sparks or other open flames. ； If the mixture of hydrogen and chlorine reaches the explosive limit, it will also explode when exposed to light. The synthesis of trichlorosilane is carried out at a temperature of 280 degrees Celsius to 300 degrees Celsius, which has exceeded its auto-ignition temperature (175 degrees Celsius). During the synthesis process, if trichlorosilane leaks or air enters the reactor, it can easily cause combustion, explosion or poisoning accidents. If the trichlorosilane storage tank leaks, the risk is far greater than that of the process pipeline leakage. Because of its large storage capacity, if the leakage is not plugged in time, the impact will continue to expand. At the same time, the leaked trichlorosilane will react with water, producing toxic hydrogen chloride gas that spreads around, making rescue operations difficult. Fire and explosion-proof countermeasures In each process of trichlorosilane production, in order to prevent fire and poisoning accidents, fire safety systems must be strictly implemented and process indicators must be strictly controlled. Fire management. The tools used during maintenance should be non-sparking tools. It is strictly forbidden to use iron tools to knock equipment or pipes. Workers should wear cotton overalls. Open flames are prohibited in production and storage tank areas, and relevant safety management systems must be strictly followed when using fire during production. Prevent running, popping, dripping and leaking. Safety inspections should be carried out in daily work and no blind spots should be left. Equipment should be inspected regularly, and remedial measures should be taken promptly if problems are found. Equipped with emergency tools and fire-fighting facilities. Enterprises that produce trichlorosilane should be equipped with a certain number of gas masks, self-contained air breathing apparatus, gloves, leak-stopping tools, fire extinguishers and other emergency tools and fire-fighting facilities. Emergency team members should conduct regular drills and become proficient in leak plugging and disposal methods under various circumstances. A check valve should be installed between the hydrogen chloride gas buffer tank and the synthesis furnace to prevent trichlorosilane in the synthesis furnace from returning to the buffer tank. The flow rate of hydrogen chloride gas should be controlled and the temperature in the synthesis furnace should be controlled. Equipment and pipelines must be maintained regularly. During production, ensure that the entire system is sealed and protected with 99.99% nitrogen. Trichlorosilane has a low boiling point and must be stored under low temperature conditions. The storage tank should be equipped with a low-temperature protection device and take cooling measures. A certain fire prevention distance should be left between storage tanks and production equipment, and fire embankments should be set up. Gate valves should be installed where the cooling water discharge pipe passes through the fire embankment. Storage tanks should be equipped with electrostatic grounding devices and lightning protection devices. The gas phase in the storage tank should be connected to the nitrogen system. The balance pipe connecting the gas phase of the storage tank to the outside should be connected to the exhaust gas recovery system, which cannot be directly emptied, and should be equipped with a check valve and a flame arrester. A backup tank should be installed in the storage tank area so that leaking materials can be transferred to the backup tank in an emergency to prevent large-scale leakage. Leak treatment and fire fighting If trichlorosilane leaks occur during the production and storage process, a warning area should be drawn based on the size of the leakage, and irrelevant personnel and vehicles should be prohibited from entering the warning area. Cut off all fire sources in the warning area and quickly move people in the leaked contaminated area to a safe area. If the storage tank leaks and the leak cannot be plugged in time, the remaining trichlorosilane in the storage tank should be pressured into the backup tank with nitrogen. If leakage occurs in equipment and pipelines during production, production should be stopped immediately, relevant valves should be closed quickly, and material transportation should be cut off. When there is a water source in the leakage area, sand should be used to form an isolation zone to isolate the leaked trichlorosilane from the water. When emergency personnel enter dangerous areas, they should wear self-contained breathing apparatus or gas masks and first identify the leak situation. Since the container storing trichlorosilane is a normal-pressure container, different leakage plugging measures should be taken for different leakage locations, the leakage source should be cut off, and sand and cement should be used to absorb the residual liquid. When combustion occurs after trichlorosilane leaks, dry sand, carbon dioxide, dry powder, and cement should be used to extinguish the fire. Direct water and foam are prohibited.