Antipyrogenes

ANTIPYROGENES (EN: antipyrogenes; DE: Antipyrogene; FR: antipyrogenes; ES: antipirogenos; RU: антипирогены) are the substances, which hinder the self-ignition of useful minerals (of coal, ore, peat, and others) within the underground mines, within the open pit mines, within the dumps of the waste rock, and so on. The activity of antipyrogenes is directed onto the decreasing of the activity of reactions on the absorbing surface of useful minerals or for the decreasing of the area of surface. Antipyrogenes provide the mechanical, chemical, and chemical-mechanical impact. With the help of antipyrogenic mechanical activities, there is performed the plugging of microcracks on the surface of useful minerals with the help of protective preservative films.

Antipyrogenic chemical reagents enter into reaction within the adsorption layer of useful minerals, decreasing its activity, or emit gaseous products during decomposition at the conditions of the low (less than 20 degrees Celsius) or high temperatures, hindering the rate of oxidation. Another type of antipyrogenic chemical reagents are the substances, which are forming during decomposition new products, which are reacting with useful minerals. Antipyrogenic chemical-mechanical reagents decrease the size of the absorbing surface, and decrease the activity of the harmful additives.

They use within the mines as antipyrogenes the aqueous solutions of the calcium chloride, phosphate, carbonate, nitrate, ammonium sulphate, potassium manganate, phenol formaldehyde resin, polyacrylamide, suspensions of the lime mortar, inert dust, talc schist, milled slag from the open hearth furnace, milled slag from the blast furnace, waste dump sands from the aluminuium smelting plants, wastes from the soda plants. Within the coal open pit mines, piles and dumps of the waste rock, they also use the phthalic and naphthenic acids, furfural and wastes of the chemical productive enterprises (methanol water, wastes from the workshops of caprolactam, and others). For the increasing of effectiveness of reagents, and for the decreasing of consumption, they use the mixtures of various antipyrogenes.

Within the coal industry, the most common solutions are: 15-20% of calcium chloride, and suspension of 5.10% calcium hydroxide. They inject antipyrogenes through boreholes and drilled wells into the coal pillars, and into the clusters of the self-igniting coal within the goaf spaces. During the preventive processing, the consumption of the solution of antipyrogenes is at least 15-20 litres per 1 cubic metre of coal. They prepare the aqueous solutions and suspensions at the land surface and within the underground workings.