What Are Foam Fire Extinguishing Agent(I)

- Oct 04, 2019-


Foam fire extinguishing agent can fight flammable liquid effective fire extinguishing agent, it is mainly in the liquid surface to produce condensed foam floating layer, suffocating and cooling. Foam extinguishing agents are divided into chemical foam, air foam, fluorin foam, water-forming film foam and soluble foam.It has Wide range of applications.


Chemical foam extinguishing agent (MP)

Commonchemical foam extinguishing agents, mainly acidic salts (aluminum sulfate) and alkaline salts (sodium bicarbonate) mixed with a small amount of foaming agent (plant hydrolysis protein or licorice powder), a small amount of stabilization agent (iron trichloride) and other foams, the reaction is as follows:

6NaHCO3 TenAl2 (SO4)3 s 2Al (OH)313Na2SO416CO2 Chemical foam extinguishing agent spawns a large amount of carbon dioxide gas, which acts with foaming agent to produce many bubbles. The foam is small in density and sticky, covering the surface of the fire to keep out the air.

At the same time, carbon dioxide is an inert gas, does not fuel.

Chemical foam fire extinguishing agents cannot be used to fight fires of chemicals and electrical equipment that are afraid of water-free acids.

Introduction to aluminum sulfate, the main component

Chemical properties are very easy to dissolve in water, aluminum sulfate can not be dissolved in pure sulfuric acid (just co-existence), in the sulfuric acid solution and sulfuric acid dissolved in water, so aluminum sulfate in sulfuric acid solubility is the solubility of aluminum sulfate in water. The normal temperature is produced containing 18 molecules of crystalline water, 18 water sulfate aluminum, industrial production is more than 18 water sulfate aluminum.

Aluminum sulphate containing 51.3% of the waterless sulphate, even if 100 degrees C will not be self-soluble (soluble in its own crystalline water). Aluminum sulfate is not easily weathered and loses crystalline water, relatively stable, heating will lose water, high temperature will be broken down into alumina and sulfur oxides. The heating began to break down into alumina, sulfur trioxide, sulfur dioxide and water vapor. Soluble in water, acids and alkalis, insoluble in ethanol. The aqueous solution is acidic. After hydrolysis, aluminum hydroxide is generated. Aqueous solution sepsis for a long time produces alkaline aluminum sulfate. Industrial products are gray-white flakes, granular or blocky, with light green because of low iron salt, and yellowing the surface due to oxidation of low-cost iron salts. The rough is a porous shape of a gray-white fine crystal structure.

Non-toxic, dust can stimulate the eyes.

Introduction to sodium bicarbonate, the main ingredient Sodium bicarbonate, commonly known as "small soda", "soda powder", "heavy Cao", white fine crystals, in water less solubility than sodium carbonate. Solids above 50 degrees C begin to gradually decompose to produce sodium carbonate, carbon dioxide and water, 270 degrees C when completely decomposed. Sodium bicarbonate is a strong alkali and weak acid after the neutral generation of acid-type salts, soluble in water presents a weak alkaline. This feature is often used as a puffer agent in the food production process.

Sodium bicarbonate will remain sodium carbonate after the action, too much use will make the finished product alkali taste. Role and use: the paper industry as a pine glue, wax emulsion and other adhesive spree, water treatment as flocculants, but also as foam fire extinguishers, the manufacture of industrial aluminum sulfate alum, aluminum white raw materials, petroleum decolorization, deodorant, raw materials for certain drugs. It can also manufacture artificial gemstones and high-grade ammonium alum.

Products with arsenic content of no more than 5 mg/kg can be used to treat water flocculants.


Air foam extinguishing agent (MPE) 

Air foam is a normal protein foam; it is a membrane-like foam group that is produced by a certain proportion of foam, water, and air that is mechanically mixed with each other. The relative density of the foam is 0. 11-0. 16, the gas in the bubble is air.

Foam liquid is an animal or plant protein-like substance that is hydrolysised.

The role of air foam extinguishing agent is that when it covers the surface of flammable or flammable liquid with a certain thickness, it can prevent flammable or flammable liquid vapor from entering the flame area, so that the air is isolated from the liquid surface, but also prevent the flame area heat into the surface of flammable or flammable liquid.

At high temperatures, air foam extinguishing agent seweds the bubbles that can be quickly destroyed due to thermal expansion, so it is not appropriate to use them at high temperatures.


The aqueous solution that makes the foam can be dissolved in alcohol, acetone and other organic solvents, causing the foam to be destroyed, so the air foam is not suitable for the fire of organic solvents such as alcohol, ketones, ethers, and not suitable for water-free chemicals.

foam fire extinguishing agent