INVESTIGATION OF DRY CHEMICALS MODIFIED BY HYDROPHOBIC ADDITIVES BASED ON PEAT RAW

It is known, the degree of dispersion (grinding) powder determined by the size of its particles plays an important role in fire fighting. The greater dispersion of powder (the smaller particle size) is, the higher its fire extinguishing capability will be. But in this case, some performance characteristics of highly dispersed powder impair: it increases the capacity for water absorption and, as a consequence, to caking and lump formation. Importance of the study is due to the development of new types of waterproofing additives, which have a relatively low cost with high quality characteristics. It is proposed to use peat as raw material for the hydrophobic modifying agents. The large part (37 percent) of the world reserves of this raw material is located in the territory of the Russian Federation. The purpose of research is the use of hydrophobic-modifying agents (HMA) on the basis of organic matter of peat as a water-repellent agent in fire extinguishing powders. In connection with the intended purpose the paper solves the complex of interconnected problems: first, the optimization of the concentration of the HMA in the powder, and secondly, a comparative analysis of the control and water-repellent properties of modified powders, and thirdly, the definition of a minimum flow in the standardized fire source. Hydrophobic-builders, used as an additive to fire extinguishing powder, are the product of a process of low-temperature thermochemical decomposition of organic matter of peat ground (particle size less than 50 microns), based on the decomposition of organic compounds and sorption of liquid products (bitumen components) on the surface of fine peat particles. In conducting research the additive (HMA) was contributed at certain levels in the semi-finished extinguishing powder (made without traditionally used hydrophobe additive — aerosil). The studies have revealed that supplementation of the ÍMA-series additives as a hydrophobic component allows to attach the components the hydrophobic properties to the components of fire extinguishing powder, to reduce susceptibility to moisture absorption and to increase the extinguishing effect. Moreover, the practice of using this type of additives in grinding of various kinds of mineral materials shows that they are good intensifiers for grinding and allow to increase conditional specific surface of particles (other things being equal) by at least 5–10 %.