ANALYSIS OF MODERN TECHNOLOGIES FOR EXTINGUISHING ACTIVE METALS

Проведен анализ огнетушащих составов, применяемых для тушения активных металлов (пожары класса D). Отмечено, что основные современные средства обеспечения пожаротушения представляют собой галогенсодержащие соли (фториды или хлориды щелочных и щелочно-земельных металлов), препятствующие доступу кислорода без ингибирующего эффекта по отношению к самому горящему металлу. При этом данные солевые композиции не лишены недостатков из-за их высокой гигроскопичности (содержания кристаллизационной воды), что усложняет тушение. Ввиду последнего разработка более эффективных огнетушащих составов для тушения активных металлов является достаточно актуальной и перспективной.
 Ignition of active metals and their alloys often results in significant material damage. This determines the relevance for development of means to eliminate the possibility of ignition of metals and their alloys in zones of their most likely occurrence - during their melting and refining in metallurgical processes, in the technological processes of their processing and manufacturing of products by enterprises of various industries. For these purposes it is necessary to equip both consumers and special fire departments with highly effective means to ensure fire safety. Burning of active metals is characterized by a very rapid development of the oxidation reaction in the air due to their high reactivity. At the same time, for example, in a D1 class fire (burning of light metals except alkaline), the upper temperature threshold can reach 3000 °C. Alkaline and alkaline-earth metals are able to sustain combustion with limited air oxygen or contact with nitrogen or oxygen-containing substances. Extinguishing metals and their compounds differs from extinguishing fires of other classes. The main extinguishing agent used at protection facilities is a special purpose extinguishing powder. Class D fire extinguishing with a special purpose extinguishing powder consists in creating a protective layer on the burning surface. The use of calming nozzles practically prevents the formation of the air suspension when applying a fire extinguishing agent to burning area. Thus, the principle of extinguishing metals with powder extinguishing agents is to isolate and interrupt the chain reaction of burning. Despite the sufficient effectiveness of the powder compositions used, there was also identified a number of significant drawbacks in the work: a large consumption of extinguishing agent, the difficulty of supplying extinguishing agent to the hearth due to high temperature, the high cost of special extinguishing powders of a new generation, etc. As a matter of fact, it is concluded that the search for more effective means of extinguishing fires of metals and their alloys is relevant and promising, with the absence of these shortcomings.