How to deal with powder fire and what is the correct way to extinguish it

Powder is actually powder. It is divided into: organic dust and inorganic dust.

Inorganic dusts include: mineral dust (coal dust, etc.), metal dust, etc. (aluminum, magnesium).

1. The requirements for extinguishing inorganic dust fire are high, and there are many requirements for fire extinguishing agents

1) Mineral dust: combustion will produce a large amount of toxic gases, and gas masks are required.

Among them, pulverized coal is a hollow loose structure, which is easy to smolder, so special attention needs to be paid to prevent re-ignition.

Fire extinguishing agent selection "1": water mist spray gun, water mist fire extinguisher.

Reason for choosing: It can extinguish combustion, and it can also wet the dust and reduce the dust concentration to reduce the ** limit.

Protects against dust**.

Happen. Fire extinguishing agent selection "2": carbon dioxide fire extinguisher.

Reason for choosing: In addition to the suffocation effect, it also has a cooling effect and suffocates the flame.

Fire taboos: avoid using direct current jet water and foam, which will impact the dust and cause the dust to diffuse to the first limit, and at the same time, the carbon dioxide fire extinguisher should not directly impact the dust, and it will also impact the dust and cause the dust to spread to the first limit.

2) Metal dust, etc. (aluminum, magnesium): reacts with water during the combustion process to form a ** mixture. Carbon tetrachloride, 1211 fire extinguishers cannot be used.

Catalysis will occur. The sand layer is mostly used to isolate the combustion dust and make it burn out.

Fire extinguishing agent selection: 7511 fire extinguisher, chemical dry powder fire extinguisher.

Dry sand, graphite powder.

Reason for choosing: Cover the burning surface, isolate the air, effectively prevent the splash of aluminum powder from mixing with the air, and achieve the purpose of extinguishing the fire.

Fire contraindications: react with water during combustion to form a ** mixture. Carbon tetrachloride and 1211 fire extinguishers cannot be used, and catalytic effects will occur.

At the same time, 7511 fire extinguishers and chemical dry powder fire extinguishers should not directly impact the dust, but also impact the dust, causing the dust to spread to the limit.

2. Organic dust includes: plant dust, animal dust, and artificial organic dust.

Organic dust is mainly grain, taking plant dust as an example, plant dust burns quickly, spreads quickly, and is easy to react with oxygen under the condition of rapid increase in pressure and temperature.

Occurrence of chemical ** and incidental secondary **.

Fire extinguishing agent selection: gases such as carbon dioxide, heptafluoropropane.

gas mixtures; Water-based fire extinguishing agents: such as foam fire extinguishing agents, water sprays, and water mist; Dry powders: such as ABC dry powder, ultra-fine dry powder and aerosol.

class, hot aerosol and other products. (Dry chemical fire extinguisher recommended).

Reason for choosing: gases have little effect on smoldering of food, heptafluoropropane is also low toxicity and is not suitable for the food industry, although the water-based fire extinguishing agent is effective for smoldering, but it is devastating to food; Moreover, aerosols can not be used, high temperature can cause secondary combustion, and there is low toxicity and residues are not easy to remove, which is a prohibited product in the food industry.

Fire taboos: avoid using direct current jet water and foam, which will impact the dust and cause the dust to diffuse to the highest limit, and at the same time, carbon dioxide and other gas fire extinguishers should not directly impact the dust, and the dust will also impact the dust and cause the dust to spread to the first limit.

Covering with sand is more reliable and can cope with most types of powder fires.

Gas caused a disaster, and it cannot be extinguished with dry powder.

Dry powder fire extinguishers are suitable for extinguishing initial fires of flammable liquids, combustible gases and electrical equipment such as petroleum and organic solvents, and can also extinguish fires caused by the combustion of oil and gas. Because, the dry powder fire extinguisher is filled with ammonium phosphate dry powder fire extinguishing agent.

Therefore, dry chemical fire extinguishers cannot extinguish metal fires, because the medium in the equipment will produce hydrogen with light metals, which will cause larger fires.