RU2520483C1 - Emulsion explosive composition for forming blasthole charges - Google Patents

Abstract

FIELD: blasting operations.

SUBSTANCE: emulsion explosive composition (EEC) comprises as the oxidising phase the aqueous solution of ammonia and sodium or calcium nitrate and urea, and as the hydrocarbon phase the wax melt of fine crystalline or ceresin, individually or their mixture, with the emulsifier for industrial emulsion of explosives, individually or as specified emulsifier with tall oil rosin, oleoresin pine rosin, or their mixture, and as the sensitising agent - the aqueous solution of sodium nitrite, or polymeric microspheres or a their mixture. The effect of the invention is achieved by equilibrium ratio of components ensuring normalised density of emulsion matter equal to 1.00-1.20 g/cm³.

EFFECT: high explosive and operational characteristics, including physical stability of the EEC during prolonged storage, good sensitivity to the explosive pulse of standard primary means of initiation, small critical diameter, satisfactory propagation of detonation in the distance between the two cartridges, the high heat of explosion.

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Description

The invention relates to the field of explosive compositions intended for the formation of blast holes for the purpose of blasting, both on the earth's surface and in underground mine workings, non-hazardous in gas or dust.

There are a number of emulsion explosive compositions (EMUs) used for blasting with bore charges on the earth's surface (for example, RF application for invention No. 99113834/02, class C06B 31/28, filed July 1, 1999, published in 2001 B. No. 14).

A common recipe for such formulations is the presence of a dispersion of an aqueous solution of oxidizing agents mixed with hydrocarbon fuel and an emulsifier in the presence of sensitizers - mechanical (glass, polystyrene, phenol-formaldehyde microspheres, aluminosilicate microspheres from waste from thermal power plants, foamed perlite sand) or chemical (aqueous sodium nitrite and sodium nitrite formaldehyde sodium nitrite solution).

There is currently no evidence of the presence of emulsion explosive formulations specifically designed for the formation of drill holes for the purpose of blasting on the earth's surface and in underground mine workings that are not hazardous in gas or dust.

Closest to the claimed emulsion explosive composition in terms of the components used is the composition (RF patent for the invention No. 2143488, class C06B 31/28, claimed 01.02.1994, published 20.12.1998), in which the mass fraction of components has the ratio (mass%):

sodium nitrate - 5.0 ÷ 15.0;

or calcium nitrate - 5.0 ÷ 25.0;

and / or ammonium chloride - 5.0 ÷ 15.0;

or methylamine nitrate - 5.0 ÷ 15.0;

or ethylenediamine dinitrate - 5.0 ÷ 30.0;

or sodium perchlorate - 5.0 ÷ 25.0;

water - 5.0 ÷ 25.0;

industrial oil - 2.0 ÷ 7.0;

petrolatum - 0.5 ÷ 4.0;

paraffin 1.0 ÷ 2.0;

or bitumen - 0.5 ÷ 2.5;

the condensation product of a polyolefin with maleic anhydrite and alkanomilamine or polyol, or a mixture of these products with fatty acid esters of the C ₁₇ -C ₂₅ fraction, or tall oil fatty acid esters with glycerol or polyglycerol, or pentaerythritol - 1.0 ÷ 3.0;

sodium nitrite - 0.2 ÷ 5.0;

or a mixture of a solution of sodium nitrite with formalin (3: 1) -0.005 ÷ 5.0;

or glass microspheres - 2.0 ÷ 6.0;

or phenol-formaldehyde microspheres - 3.0 ÷ 7.0;

or polystyrene microspheres - 3.0 ÷ 6.0;

or microspheres from waste from CHP - 4.0 ÷ 10.0;

or perlite - 2.0 ÷ 6.0;

ammonium nitrate - the rest is up to 100.

In addition, the explosive composition may contain energy additives in an amount of from 3.0 to 15.0%.

Even a surface analysis of this emulsion explosive composition reveals the presence of highly toxic fire hazardous individual explosives that are sensitive to mechanical stress - impact and friction, as well as substances that are sensitive to elevated temperatures, spark discharges, and open flames (ammonium chloride, methylamine nitrate, ethylene diamine dinitrate, sodium perchlorate).

In addition, in the analyzed emulsion explosive composition there are a lot of thickening coarse-grained substances (petrolatum, paraffin, bitumen) capable of forming conglomerates of uncontrolled shape and size in the volume of emulsion explosives as a result of crystal growth and their intergrowth when the manufactured explosive is cooled and the composition is stored for a long period of time.

The uneven distribution of components over the EMU volume and the presence of conglomerates of thickeners entail an increase in the critical diameter of detonation and a decrease in explosive characteristics - sensitivity to the explosive pulse of the primary means of initiation, detonation speed, transfer of detonation to the distance between two cartridges up to the complete loss of detonation properties.

The use of sensitization of emulsion explosive compositions for blast holes using phenol-formaldehyde or polystyrene microspheres, and even more so microspheres from waste from thermal power plants or foamed perlite sand, is unacceptable - sharply increase the critical detonation diameter, destroy microdroplets of the emulsion matrix due to abrasive friction during mixing, which is accompanied by recrystallization, which is accompanied by recrystallization oxidizing agent and the formation of conglomerates of inorganic salts.

The technical result of the present invention is the creation of an emulsion explosive composition intended for the formation of borehole charges for blasting, both on the earth's surface and in underground mine workings that are not hazardous in gas or dust, by increasing explosive characteristics and operational properties, in including the physical stability of EMU during prolonged storage.

A new emulsion explosive composition is proposed, in which there are no highly hazardous and toxic substances that detonate in paper and polymer shells of cartridges with a nominal diameter of 32-36 mm or more when the detonation process is initiated by standard primary means of initiation.

The inventive emulsion explosive composition intended for the formation of borehole charges includes water, an oxidizing phase from ammonia and sodium or calcium nitrate, a hydrocarbon phase and a sensitizer, characterized in that carbamide is introduced into the oxidizing phase at a eutectic ratio of the mass fractions of these components in the oxidizing phase or ratios close to the eutectic value, as the hydrocarbon phase contains a melt of crystalline paraffin or ceresin individually, or mixtures (for example, as a special case, in a ratio of 3: 1), with an emulsifier for industrial explosives individually or an emulsifier for industrial emulsion explosives with tall oil rosin or pine gum rosin, or a mixture thereof (for example, as a special case, in a ratio of 1 : 1), in the range of the technological process for the manufacture of EMU from 65 to 130 ° C.

The explosive composition is sensitized by the addition of polymer microspheres individually or by the addition of polymer microspheres in combination with an aqueous solution of sodium nitrite, or only with an aqueous solution of sodium nitrite.

The components of the new emulsion explosive composition are taken in the following ratio (%, mass):

sodium or calcium nitrate 5.0 ÷ 25.0 water 2.0 ÷ 25.0 urea 0.005 ÷ 15.0 fine crystalline paraffin melt or ceresin or mixtures thereof 2.0 ÷ 7.0 emulsifier for industrial explosives 0.5 ÷ 5.0 or emulsifier for industrial explosives with tall oil rosin or with rosin gum pine, or with their mixture 0.5 ÷ 10.0 aqueous solution of sodium nitrite 0.2 ÷ 5.5 polymer microspheres 0.05 ÷ 7.0 ammonium nitrate, including granular, granular porous, granular crushed or powdered or in aqueous solution the rest is up to 100

moreover, the normalized density of the emulsion explosive is equal to 1.00-1.20 g / cm ³ .

To increase explosive, operational indicators and regulate the oxygen balance, additional components can be introduced into the composition with a mass fraction from 1.0 to 15.0%.

As an emulsifier for industrial emulsion explosives, emulsifiers for industrial emulsion explosives manufactured by industry in accordance with the requirements are equally applicable:

TU 7511903-589-92. Polyglycerol tall emulsifier for industrial explosives. Technical conditions;

TU 7511903-631-93. Polymer emulsifier brand "REM". Technical conditions;

TU 84-08628424-806-2004. Polymeric emulsifying composition. Technical conditions;

TU 2484-095-07511608-2012. Emulsifier for emulsion industrial substances. Technical conditions;

TU 38.4011014-94. Emulsifier BC-1. Technical conditions;

Emulsifiers of the Lubrisol trademark or other foreign analogues with quality indicators not lower than those indicated.

An example of using the invention

In an aqueous urea solution previously prepared in the dissolution apparatus (at mass fractions of water - 8% and 6% urea at face value), sodium nitrate is introduced portionwise at a mass fraction of 17%.

Dissolution is carried out in the temperature range (85 ± 5) ° C with constant stirring. After dissolution of sodium nitrate, ammonium nitrate is also added portionwise with a mass fraction of 63%. The process is carried out until the components are completely dissolved.

The effect of the invention is achieved through the use of co-soluble components of the oxidative phase in a ratio close to the eutectic, and its emulsification in the hydrocarbon phase, prepared in the following order.

In a modernized Mikhailov boiler, fine crystalline paraffin with a nominal mass fraction of 4% is melted with constant mixing. The melt is transported through pipelines to a hydrocarbon phase preparation apparatus, into which an emulsifier for industrial explosives is pre-loaded individually (2%). The hydrocarbon phase is prepared with constant stirring in the range of normalized temperatures (85 ± 5) ° C until the components are completely melted.

The manufacturing process of the emulsion matrix is carried out in an emulsification apparatus. The prepared phases are transported through a network of pipelines by metering pumps, mixed together in a preliminary mixer, and then sent to the emulsification apparatus.

To regulate the oxygen balance of the EMF being manufactured, to the manufactured emulsion matrix 70-80% (mass.), Granular, granular porous, granular crushed or powdered ammonium nitrate is added in a mass fraction of 20-30%.

If necessary, components are added that increase the energy parameters of the emulsion explosives, for example, up to 4-5% (in excess of 100%) of aluminum powder.

Dosing of granular components - granular, porous or powdered ammonium nitrate, aluminum powder, as well as, for example, polymer microspheres with a mass fraction of 0.3-0.4% (in excess of 100%) is carried out in a twin-shaft mixer with longitudinal discharge.

After preliminary mixing in the mixer, the manufactured emulsion explosive composition is transferred to the cartridge section via the screw conveyor system, where cartridges of the required nominal diameters and masses are formed by the cartridge machines.

The emulsion explosive composition made by the above method has sufficient sensitivity to the explosive pulse of standard primary means of initiation, a small critical diameter, satisfactory detonation transmission between two cartridges, high heat of explosion and physical stability during storage for a year.

The proposed emulsion explosive composition is intended for the formation of borehole charges for the purpose of blasting, both on the earth's surface and in the faces of underground workings of mines and mines, not hazardous in gas or dust, from single cartridges with a nominal diameter of 32-36 mm and above or cartridges, collected in a single charge (stacked between two or more cartridges) with their direct or reverse initiation.

Claims (1)

Emulsion explosive composition (EMU), intended for the formation of borehole charges, including water, an oxidizing phase, including ammonia and sodium or calcium nitrate, a hydrocarbon phase and a sensitizer, characterized in that carbamide is introduced into the oxidation phase, containing a paraffin melt as a hydrocarbon phase crystalline or ceresin, individually or a mixture thereof, with an emulsifier for industrial emulsion explosives individually or an emulsifier for industrial emulsion explosives jerky substances with tall rosin or pine gum rosin, or a mixture thereof in the temperature range of the technological process for the manufacture of EMF from 65 to 130 ° C, and as a sensitizer contains an aqueous solution of sodium nitrite in combination with polymer microspheres or only polymer microspheres, or only water sodium nitrite solution in the following ratio of components, wt.%:
sodium or calcium nitrate 5.0-25.0 water 2.0-25.0 urea 0.005-15.0 fine crystalline paraffin melt or ceresin or mixtures thereof 2.0-7.0 emulsifier for industrial explosives 0.5-5.0 or emulsifier for industrial explosives substances with tall oil rosin or with rosin gum pine, or with their mixture 0.5-10.0 aqueous solution of sodium nitrite 0.2-5.5 polymer microspheres 0.05-7.0 ammonium nitrate, including granular,
granular porous, granular crushed
either powdered or in aqueous solution the rest is up to 100,
moreover, the normalized density of the emulsion explosive is equal to 1.00-1.20 g / cm ³ .