RU2305672C1 - Method of manufacture of the patronized emulsion blasting explosive - Google Patents

Abstract

FIELD: chemical industry; mining; methods of manufacture of the patronized emulsion blasting explosive.

SUBSTANCE: the invention is pertaining to the industrial blasting explosives used as the borehole charge in the open mining operations. The patronized emulsion blasting explosive is produced by mixing of the water solution of the oxidizing agent with the oil-based component with the subsequent mixing of the cooled produced emulsion with the sensitizer. The water solution of the oxidizing agent is being prepared at the constant stirring action by injection of carbamide into the water heated up to 35-45°C, the following heating of the produced solution up to 60-70°C, the step by step injection in it of sodium nitrate or calcium nitrate, heating of the produced solution up to 75-85°C, injections of the ammonium nitrate with the subsequent stirring action of the received solution at 80-90°C. The oil-based component is being prepared by feeding of the emulsifier into the heated up to 50-60°C industrial oil with the subsequent stirring action, heating of the produced mixture up to 73-78°C and injection of paraffin. The invention allows to improve stability of the emulsion at its transportation and storing, and also to reduce its sensitivity to the mechanical actions and to increase its sensitivity to the initiating impulse.

EFFECT: the invention ensures the increased stability of the emulsion at its transportation and storing, the reduced its sensitivity to the mechanical actions and the increased sensitivity to the initiating impulse.

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Description

The invention relates to industrial explosives, used as a drill hole or borehole charge in underground and opencast mining, in particular in the development of mineral deposits.

A known method of manufacturing a cartridge emulsion explosives by dispersing aqueous solutions of nitrates in an organic medium in the presence of an emulsifier with the addition of hydrazine nitrate as sensitizers (EP No. 598115). However, hydrazine nitrate is unstable, which drastically reduces the manufacturability of the method of preparation of cartridge emulsion explosives.

There is also a known method of manufacturing cartridge emulsion explosives, in which the sensitizer is glass or polymer microspheres (RU No. 2024468).

When implementing the known method, as well as in others involving the use of such sensitizers, serious difficulties arise when choosing the amount of sensitizer, which, on the one hand, should ensure the safety of the use of explosives, and on the other hand, its high detonation ability.

Closest to the proposed invention is a method of manufacturing a cartridge emulsion explosive by preparing an aqueous solution of an oxidizing agent by mixing water, urea, ammonium nitrate and metal nitrate, preparing an oil component by mixing industrial oil, paraffin and an emulsifier and then mixing an aqueous solution of an oxidizing agent, an oil component and a sensitizer, representing glass or polymer microspheres or perlite sand (RU No. 37202).

The known method is as follows.

In 9.5-11.5 wt.% Water, 70-76 wt.% Ammonium nitrate, 9.5-11.5 wt.% Sodium nitrate and 1-3 wt.% Urea are dissolved and an oxidizing solution is obtained. Separately, 0.5-2.5 wt.% Paraffin and 0.5-4.0 wt.% Industrial oil are mixed. Up to 1 wt.% Of the resulting mixture is used to impregnate the sensitizer, 1-2 wt.% Of the emulsifier is introduced into the rest of the mixture and an oil component is obtained. Then, the oil component is mixed with an oxidizing solution, and the impregnated particles of the sensitizer are introduced into the emulsion obtained. The amount of sensitizer (1-5 wt.%) Is calculated per 100 wt.% Of the finished emulsion. The resulting emulsion explosive should have a density of 1000-1180 kg / m ³ .

To achieve the technical result of the known method, which consists in obtaining an emulsion explosive with low sensitivity to mechanical stress and high sensitivity to the initiating pulse, it is necessary to carry out the manufacturing process so that the dispersed phase of the emulsion has an average globule size of less than 10 microns. The size of the globules, in addition to the indicated one, is also decisive for the stability of the emulsion — a property necessary to ensure the stability of the cartridge explosive during its transportation.

However, as a result of the studies, it was found that even if an emulsion is obtained with an average globule size of a dispersed phase of less than 10 μm, the necessary stability of the emulsion is not achieved. Obviously, this is due to the fact that another necessary condition is the size distribution of the globules (polydispersity), and only when the optimum value is reached the emulsion explosive possesses the necessary stability of properties during transportation and storage, while having a low sensitivity to mechanical stress and high sensitivity to the initiating impulse.

Since the polydispersity of the dispersed phase, as one of the indicators of the emulsion, depends on the method of its preparation, the objective of the invention was to develop a method for producing a cartridge emulsion explosive, which would allow to obtain an emulsion explosive with such a set of properties that can ensure its high storage stability and transportation, as well as high performance.

The technical result of the invention is to increase the stability of the properties of the cartridge emulsion explosive during transportation and storage, reduce its sensitivity to mechanical stress and increase sensitivity to the initiating pulse.

The specified technical result is achieved by the fact that in the method of manufacturing a cartridge emulsion explosive by preparing an aqueous solution of an oxidizing agent by mixing water, urea, ammonium nitrate and metal nitrate, preparing an oil component by mixing industrial oil, paraffin and an emulsifier and then mixing an aqueous solution of an oxidizing agent, an oil component and sensitizer, which is a glass or polymer microspheres or perlite sand, an aqueous solution of the oxidizing agent is ready t with constant stirring by introducing urea into water heated to 35-45 ° C, heating the resulting solution to 60-70 ° C, gradually introducing into it, as metal nitrate, sodium nitrate or calcium nitrate, heating the resulting solution to 75- 85 ° C, the introduction of ammonium nitrate, followed by stirring the resulting solution at 80-90 ° C, the oil component is prepared by feeding the emulsifier into industrial oil heated to 50-60 ° C, followed by stirring, heating the mixture to 73-78 ° C and introducing paraffin wax then mixing the oil component with an aqueous solution of an oxidizing agent, cooling the resulting emulsion to room temperature and its subsequent mixing with a sensitizer, the process being carried out in the following ratio of ingredients, wt.%:

Ammonium nitrate 65.9-71.9 Sodium Nitrate or Calcium Nitrate 9.9-10.7 Urea 1.0-3.0 Water 9.9-10.7 Industrial oil 1.9-4.9 Paraffin 0.5-2.5 Emulsifier 0.5-2.0 Sensitizer 1.0-5.0

As an emulsifier can be used any emulsifiers commonly used in industry for the preparation of emulsion explosives: such as emulsifiers of the grades ANS-6, Span-80, Atsurf-5000, SEM, etc. It is preferable to use emulsifiers, which are a composition of fatty esters acids and polyhydric alcohols with fatty amines (emulsifier brand INS-6 according to TU 2483-104-05744685-94).

As industrial oil use any industrial oil, for example, grades I-12A, I-20A, I-30A, I-4A, I-50A (GOST 20799-88), as well as S-9, S-15 (TU 38.10133 -75). The latter oils are preferably used in the winter, when the temperature reaches values below (-10) ° C.

Glass or polymer (for example, polystyrene) microspheres or perlite sand (for example, sand from expanded perlite) are used as a sensitizer, and the technical result is achieved to the same extent.

The technical result also does not depend on the choice of metal nitrate (calcium nitrate or sodium nitrate).

Example 1

Preparation of an oxidizing solution.

In a container equipped with a stirrer and a coil of hot water, load 31 kg (9.9 wt.%) Of water, heat it to 35 ° C and begin dosing of urea - 6.6 kg (2.0 wt.%). The entire process of preparing the solution takes place with continuous stirring. After all the urea is loaded, the temperature of the solution is raised to 60 ° C and 31.0 kg (9.9 wt.%) Of sodium nitrate is gradually introduced, the temperature of the resulting solution is raised to 75 ° C and 206 kg (65.9 wt. .%) ammonium nitrate, raise the temperature to 80 ° C, the resulting oxidizing solution is mixed and fed into the mixer for mixing with the oil component.

Preparation of the oil component.

15.3 kg (4.9 wt.%) Of industrial oil of brand I-12A is heated to 50 ° C in a tank equipped with a stirrer and a coil with hot water. The entire process of preparing the oil component takes place with continuous stirring. 6.6 kg (2.0 wt.%) Of the INS-6 brand emulsifier is loaded into the heated oil, mixed, the temperature is brought to 73 ° C and 7.8 kg (2.5 wt.%) Of paraffin is introduced, the contents of the container are mixed and served in a mixer with a solution of an oxidizing agent.

The aqueous solution of the oxidizing agent and the oil component forming the emulsion mixed in a mixer are cooled to room temperature and fed into a container for mixing with a sensitizer (glass microspheres), which is preloaded in an amount of 9.0 kg (2.9 wt.%). The contents are mixed, and the resulting emulsion explosive composition is served for patronage. Patronage is carried out in a polyethylene (PE) hose, the ends of which are clamped with clips.

Examples 2-3.

The method is carried out as in example 1, the temperature conditions of the stages were selected from the above ranges, the mass ratio of components and product characteristics according to examples 1-3 are shown in the table, the performance of the prototype method is given for comparison.

Table Indicators Prototype Example 1 Example 2 Example 3 Composition, wt.%: Ammonium nitrate 74.0 65.9 66.3 71.9 Sodium nitrate 10.0 9.9 - 10.0 Calcium nitrate - - 10.7 - Urea 2.0 2.0 3.0 1,0 Water 10.0 9.9 10.7 10.0 Industrial oil 2.0 4.9 2.0 1.9 Paraffin 1,0 2,5 1,5 0.5 Emulsifier 1,0 2.0 0.8 0.5 Glass microspheres - 2.9 - - Polystyrene microspheres - - 5,0 - Perlite sand 2.0 (over 100%) - - 4.2 Total, wt.% one hundred one hundred one hundred Shelf life, months 6 More than 8 More than 8 More than 8 Emulsion stability, 80 ° C, h 40 More than 48 More than 48 More than 48 The speed of the bullet causing the reaction (Nitro Nobel method), m / s 650 Over 700 Over 700 Over 700 Sensitivity to shock according to GOST 4545-88 at 20-80 ° С, lower limit, mm 500 More than 500 More than 500 More than 500 The critical diameter of the detonation in the shell, mm thirty twenty twenty twenty

Claims (1)

A method of manufacturing a cartridge emulsion explosive by preparing an aqueous solution of an oxidizing agent by mixing water, urea, ammonium nitrate and metal nitrate, preparing an oil component by mixing industrial oil, paraffin and an emulsifier and then mixing an aqueous solution of an oxidizing agent, an oil component and a sensitizer comprising glass or polymer microspheres or perlite sand, characterized in that the aqueous oxidizing solution is prepared with constant stirring of pu I am introducing urea into water heated to 35-45 ° С, heating the resulting solution to 60-70 ° С, gradually introducing sodium nitrate or calcium nitrate into it as metal nitrate, heating the resulting solution to 75-85 ° С, introducing nitrate ammonium, followed by stirring the resulting solution at 80-90 ° C, the oil component is prepared by feeding the emulsifier into industrial oil heated to 50-60 ° C, followed by stirring, heating the resulting mixture to 73-78 ° C and introducing paraffin, then the oil is mixed component and with an aqueous oxidant solution, cooling the obtained emulsion to room temperature, and its subsequent mixing with the sensitizer, and the process is carried out with the following ratio of ingredients, wt.%: Ammonium nitrate 65.9-71.9 Sodium Nitrate or Calcium Nitrate 9.9-10.7 Urea 1.0-3.0 Water 9.9-10.7 Industrial oil 1.9-4.9 Paraffin 0.5-2.5 Emulsifier 0.5-2.0 Sensitizer 1.0-5.0