Core-shell type composite fire-extinguishing powder and preparation method thereof

Abstract

The invention discloses a core-shell type composite fire-extinguishing powder and a preparation method thereof. The preparation method is characterized by comprising the following steps: adding refined zeolite with an average particle size of 10 [mu]m or less into a water solution (0.01-0.10 mol / L) containing sodium bicarbonate and potassium bicarbonate / ammonium dihydrogen phosphate, wherein the refined zeolite accounts for 78% to 90% of the weight of the system and the water solution accounts for 8% to 18% of the weight of the system; mechanically stirring the mixture for 4 to 8 hours at a speed of 300 to 600 r / min; carrying out a vacuum freeze-drying treatment on the solution at a temperature of -10 to -30 DEG C under a pressure of 1.3 to 13 Pa, adding silica accounting for 0.5 to 1.05 of the weight of the system and talcum powder accounting for 1.5 to 3.0% of the weight of the system into the obtained powder, and evenly mixing the powder together so as to obtain the target product. The composite fire-extinguishing powder has the advantages of high fire-extinguishing efficiency, cheap and available raw materials, and simple preparation technology, can be directly applied to the conventional dry powder fire extinguishers, and is suitable for various types of fires such as fire on solid substances, fire on flammable gas, fire on liquid, and the like.

Description

【Technical field】 [0001] The invention belongs to the technical field of powder fire extinguishing agents, in particular to a composite powder fire extinguishing agent with a core-shell structure and a preparation method thereof. 【Background technique】 [0002] Among the commonly used fire extinguishing agents such as gas, powder, water system, foam, etc., powder fire extinguishing agent is widely used because of its high fire extinguishing efficiency, fast fire extinguishing speed, environmental friendliness, non-toxicity to human body, wide source and low price. It is especially suitable for fire fighting in water-scarce areas. The fire extinguishing active components of commonly used powder fire extinguishing agents mainly include sodium bicarbonate, potassium bicarbonate, ammonium dihydrogen phosphate, etc. However, the traditional dry powder fire extinguishing agent has large particle size, fast particle settlement, and slow decomposition speed, so that the fire exting...

AI Technical Summary

Problems solved by technology

However, the traditional dry powder fire extinguishing agent has large particle size, fast particle settlement, and slow decomposition speed, so that the fire extinguishing active component particles cannot fully contact with the flame, and the fire extinguishing effect cannot be fully exerted, thus restricting the practical application range of powder fire extinguishing agent

In order to improve the fire extinguishing performance of the powder fire extinguishing agent, the main measure currently adopted is to carry out ultra-fine treatment on the powder, but the ultra-fine treatment of the powder requires special equipment, and the degree of particle size reduction is limited; while the particle size The smaller particles have a large surface energy, they are easy to agglomerate with each other, the fluidity decreases, and the fire extinguishing efficiency of the dry powder fire extinguishing agent will be reduced.