Energy condensed packaged systems. Composition, production, properties

Abstract

Introduction. Mining enterprises of Ukraine annually consume up to 150 thousand tons of industrial explosives. Until recently industrial explosives were composed of TNT -highly toxic substance that is prohibited in Europe since 1993. Transition of the mining industry on the use of domestic highperformance, safe emulsion explosives (EE) [1] almost completely renounce the use of TNT on open cast mining. At the same time in underground conditions the use of EE is limited due to a number of requirements for such systems.Literature review. It is known [1] that EE are the inverse emulsions of highly concentrated solution of oxidizer (91...93 wt %) in the hydrocarbon medium (7,0...9,0 wt %) sensitized by pore-forming components (gas generating additives). Widespread use of EE in underground mining assumes their production in package form with preservation of stability and high detonation parameters. In [2] it is shown that the best option of oxidant conforming to the specified requirements, has the following composition, wt %: Н 2 О 7,0…10,0; Ca(NO 3 ) 2 27,5…31,5; NH 4 NO 3 58,5…65,59. The composition of specified oxidant has a lower crystallization temperature compared to the monosolution of ammonium nitrate and binary solution "ammonium nitrate -sodium nitrate". This provides a maximum thermal effect of reaction of explosive conversion when interacting with a hydrocarbon medium.Usually [3] oil and products of its processing (oil, diesel fuel, industrial oils, waxes, etc.) are used as fuel phase in energy condensed emulsion systems. At the same time the value of the specific heat of fuel combustion is considered as the main parameter. This value is determined by the relation of carbon and hydrogen content in the molecule (Н/С) and has maximum value for paraffinic hydrocarbons and minimum value for aromatic ones. Besides, the viscosity characteristics of fuel phase are very important for obtaining the emulsion with specified technological parameters.Energy condensed emulsion systems which are used as industrial explosives have mixtures mechanism of detonation, so the chemical reaction proceeds between the oxidant and reductant that are not in molecular contact. According to [4], the high detonation ability of ammonium nitrate explosives can be provided by increasing the contact area of oxidizer and fuel and by the temperature increasing in chemical reaction zone. The width of chemical reaction zone determines the critical detonation diameter [5]. In its turn, the width of chemical reaction zone is determined by the speed of heat release. The speed of heat release depends on the size of oxidant globules in the emulsion, the oxidation rate of fuel phase and the pore size of emulsion, the carrier of which is sensitizer.For the production of energy condensed packaged emulsion systems it is necessary to solve the problem of producing highly viscous emulsion with minimal size of particles of the dispersed phase. Such an emulsion after entering the special materials -sensitizers -provides high detonation parameters and sen...