Author(s)

LALI GURCHUMELIA, MURMAN TSARAKHOV, SALOME TKEMALADZE, GEORGE BEZARASHVILI, LASHA TKEMALADZE

Abstract

The aim of the presented investigation is the development of the novel halogen free, environmentally safe and highly efficient universal (working on several classes of fires) fire-extinguishing powders on the basis of local mineral raw materials. The technology for production of these powders differs from the convenient production technology, is much simpler and significantly cheaper. Powders will be produced by mechanical milling of local mineral raw materials, which do not require modification with expensive halogen-containing hydrofobizing additives, making the extinguishing materials far cheaper than imported analogues. Optimal dispersity of powders was selected to provide the minimal caking capacity, a homogeneous action of combustion products on the flame and a heterogeneous inhibition of combustion process. The evaluation of powder efficiency was carried out considering the both effects. For a comprehensive evaluation of the extinguishing effect two special characteristics were selected: the reciprocal value of extinguishing “surface” concentration (“surface” concentration means a total surface area of powder particles in a unit volume) and the coefficient of recombination of atomic oxygen on the surface of solid particles (measured using Electro Paramagnetic Resonance (EPR) methods). In order to evaluate the fire-extinguishing ability of powders, the “polygon testing” methods are used, which consider extinguishing of different class of standard fires with the help of standard fire-extinguishing constructions. Experimental data confirm that the developed fire-extinguishing powders are characterized with high performance characteristics, as well as high fire-extinguishing capacity. At the same time, it should be noted, that the efficiency of the obtained powders is practically the same as of standard imported powders, but do not contain any halogens, is environmentally safe and 1.5–2 times cheaper than the imported analogues.

Keywords

halogen free, environmentally safe, highly efficient, zeolite-containing, fire-extinguishing powders