RU2544680C1 - Water-resistant emulsion explosive and emulsion composition for water-resistant explosives - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to production of safe water-resistant emulsion explosives. The water-resistant emulsion explosive contains, wt %: oil-in-water emulsion 80.00-30.00, ammonia nitrate 18.60-65.70, gas-generating agent in the form of a gasification solution 0.20-0.10 and petroleum products 1.20-4.20. The petroleum products used are diesel fuel; the oil-in-water emulsion is based on aqueous ammonium or sodium nitrate and includes 70% acetic acid, thiourea as a catalyst and 40% sodium hydroxide. The emulsion explosive includes granular ammonium nitrate which is mechanically mixed with said emulsion.

EFFECT: invention is aimed at improving stability of operational and explosive properties and improving effectiveness of the explosive effect.

2 cl, 2 dwg, 3 tbl

Description

The invention relates to the field of manufacturing safe waterproof emulsion explosive compositions for the efficient use of energy generated during the course of an explosive transformation reaction for industrial purposes.

Since the beginning of the 2000s, emulsion explosives based on disperse systems, consisting of two mutually insoluble liquids, one of which is distributed in explosive processes, are rapidly introducing explosives in mining enterprises in the territory of the post-Soviet space, in particular Kazakhstan and Russia. another in the form of the smallest drops.

One important feature of emulsion explosives is that the composition itself is not explosive without the forced regulation of the volume concentration of the emulsion charge energy, achieving its susceptibility to the initiating pulse and changing the critical detonation diameter, which is achieved by changing the emulsion density by introducing chemical agents into it (chemical gas generation) or mechanical additives (glass sphere, perlite, low-density polymers). In addition, emulsion explosives can contain granular (porous) ammonium nitrate or mixtures of the ANFO type, in which case the percentage of emulsion can vary from 30 to 70%. Due to this feature, emulsion explosives are the safest to manufacture and use in comparison with standard industrial explosives.

The well-known explosive compositions Poremit, Emulan, Granemit, Emonit, Anemiks, Emulit, which in general can be attributed to the group of emulsion explosives, as part of which are used the so-called inverse (invert) emulsions of the “water in oil” type, consisting of solutions of ammonia, sodium and calcium nitrate and a mixture of oil products with emulsifiers - V.L. Baron, V.Kh. Cantor "Technique and technology of blasting in the USA." - M .: Nedra, 1989, p. 88, 90. For the manufacture of such emulsion compositions in the world practice industrial stationary complexes are used, requiring impressive sizes of land allotments and premises with a large area, as well as a large number of auxiliary rooms and services.

Depending on the ratio of the emulsion and the dry phase (granular ammonium nitrate), many grades of these compositions can be made. In practice, use ratios ranging from 30 to 70% wt. emulsions and, accordingly, from 70 to 30% of granular ammonium nitrate. From experience it was found that mixtures with a content of more than 70% emulsion are not economical to use, because the emulsion contains water (from 13 to 18% wt.), which is not chemically involved in the explosion, is a ballast and reduces the heat of explosion. Compositions with an emulsion content of less than 30% are also uneconomical: 30-35% of the liquid phase (emulsion) is required to fill the free intergranular space of nitrate. A further decrease in the content of the emulsion in the mixture will lead to the appearance of empty air gaps between the granules, which will reduce the volumetric energy concentration of such an explosive. To achieve the effect of 100% filling of the intergranular space with an emulsion, it is necessary each time (for each batch of nitrate, for each manufacturer) to determine the free volume of the intergranular space.

The prototype of the invention is an emulsion explosive containing 10-45 wt.% Solid ammonium nitrate and up to 100 wt.% Gasified water-in-oil emulsions, the emulsion containing 13-18 wt.% Water, 3-9.5 wt. .% industrial oils, 1-3.5 wt.% emulsifier, the rest is up to 100 wt.% ammonium nitrate, gas generating additive 0.4-2.5 wt.% in excess of 100, and gasified inverse emulsion contains 0.09-6, 0 wt.% Additional component forming metal ions. Also, in the composition of the emulsion, urea 0.5-2.5 wt.% Can be included (RU 2446134, C06B 31/28, C06B 47/14, 07.23.2010).

The disadvantages of the prototype are as follows.

Firstly, due to the presence of an oxidizing phase in the composition of the emulsion in the form of an aqueous solution of only ammonium nitrate, the regulation range in the emulsion explosive composition of the oxygen balance is reduced, and the water content increases or the energy required to heat a supersaturated aqueous solution of ammonium nitrate increases to dissolve the required amount last one. As a result, the sensitivity of the emulsion to the effects of low temperatures increases.

Secondly, the presence in the formulation as a combustible phase of only industrial oils reduces the range of regulation of the viscosity of the finished emulsion.

Thirdly, the process of emulsion gas generation occurs rather slowly and the uniform distribution of gas inclusions throughout the emulsion in the required amount with certain sizes is not achieved.

Due to the above disadvantages, stability is lost and the explosive characteristics of emulsion explosive compositions made on the basis of this emulsion are deteriorated, which limits their scope. The manufacturing technology of the prototype and similar emulsions in world practice is carried out at stationary complexes (factories). For example, technological operations for the preparation of poremite components (emulsion explosives manufactured at stationary points. Consists of an emulsion and a gas-generating additive, an aqueous solution of sodium nitrate. The emulsion includes ammonium nitrate, sodium nitrate, oil products and water) at the Znamya plant (Fig. 1 is a hardware-technological scheme for preparing a poremite emulsion at the Znamya plant in Kiselevsk) are presented as follows.

The emulsifier is prepared in a separate room in a device specially adapted for this purpose at a temperature of 65 ± 2 ° C (I is the emulsifier preparation unit in Fig. 1). Petroleum products are stored in separate containers 1 for storage. The device is equipped with a heater, a mixing device, equipment and devices for dispensing components and temperature control. The finished emulsifier, heated in the emulsifier cooking reactor 2, is transported via a pipeline equipped with a steam jacket to the mixing unit for the emulsifier with mineral oils (II — the mixing unit for the emulsifier with mineral oils in FIG. 1). The preparation of the mixture is carried out with continuous stirring until a homogeneous mass.

The unit for preparing the oxidizing agent solution (III - the unit for preparing the oxidizing agent solution in FIG. 1) is located in a nearby building, where ammonia and sodium nitrate are delivered, placed in the receiving hopper 3. The bags are unpacked manually (item 4). Ammonia and sodium nitrate are separately fed by a conveyor belt 5 to the reactor 6, which is pre-filled with the amount of heated water necessary for dissolving the nitrate. Then, with continuous stirring at a temperature of 75 ° C, an oxidizer solution is prepared with a density of 1.456 g / cm ³ or 1,370 g / cm ³ depending on what type of pormemit is made. The dosage of the components is carried out by the bulk method directly in the reactor.

The finished oxidizer solution is pumped by pumps 7 into a storage tank 8, where the desired temperature is maintained.

To prepare the emulsion, the oxidizing agent solution and the mixture of emulsifier with mineral oil are fed into the reactor 9 with a mixer for preliminary mixing, after which the mixture flows into the emulsification apparatus 10 for final mixing.

The emulsification apparatus was developed by the State Research Institute "Crystal" and is a reactor with a volume of 100 to 150 liters that is hermetically sealed to prevent air leakage. The stirrer speed is 750 rpm. Mixer motor power 55 kW.

The finished water-oil emulsion from the emulsification apparatus is pumped to the mixing-charging machines 11 through the pipeline heated by a steam jacket.

The module for the preparation of gas-generating additives is located in a separate building (VI is the node for the preparation of gas-generating additives in figure 1). Water and sodium nitrite are fed into the reactor 12 with a stirrer. With continuous stirring and heating, a five percent solution of NaNO ₂ is prepared. The temperature of the prepared GGD solution pumped to the SPM is 80 ± 5 ° C.

The annual output of the installation for the preparation of the emulsion of poremite is 25 thousand tons.

A similar technological line of NPO “Crystal” is patented in SU 1790152, С06В 21/00, publ. 10/15/1994.

The technical problem that is solved by the invention is the need to create an emulsion composition that can be applied after its gas generation on its own (pumped under a column of water) or mixed with granules of ammonium nitrate (charged manually, when fed by a screw device). The technology for preparing the emulsion composition must combine safety, low power consumption, compactness, mobility of movement, minimizing staff and sufficient productivity, which entails simplification of the design and reduction in the cost of production complexes.

The present invention aims to achieve a technical result, which consists in increasing stability and increasing the efficiency of the explosion.

The specified technical result is achieved by the fact that in an emulsion explosive containing water-oil emulsion, ammonium nitrate, gas-generating additive and oil products, diesel fuel is used as oil products, the oil-water emulsion is based on an aqueous solution of ammonia and sodium nitrate, and the emulsion explosive additionally granulated ammonium nitrate, which is mechanically mixed with the specified emulsion in the following ratio of components, wt.%:

Component Name Mass fraction, wt.%, Not less than for compositions Emulsion 80.00-30.00 Ammonium nitrate 18.60-65.70 Diesel fuel 1.20-4.20 Gasification solution 0.20-0.10

The specified technical result is achieved in that the emulsion composition for waterproof industrial explosive mixtures, which is a gasified water-oil emulsion, which includes a solution of an oxidizing agent with water, ammonium nitrate and a gas-generating additive, as well as an emulsifier, additionally includes 70% acetic acid in an oxidizing solution thiourea and sodium hydroxide 40%, sodium nitrate was used as a gas generating additive, and the emulsifier was mixed with oil m to form a solution in the fuel mass fraction,% not less

Oxidizer solution Ammonium nitrate 72.00 Water 16.35 Sodium nitrate 4.00 Acetic acid 70% 0.25 Thiourea 0.25 Caustic soda 40% 0.05 Fuel solution Oil product 6.10 Emulsifier 1.00

The specified technical result is achieved by the fact that in an emulsion explosive containing water-oil emulsion, ammonium nitrate, gas-generating additive and oil products, diesel fuel is used as oil products, the oil-water emulsion is based on an aqueous solution of ammonia and sodium nitrate, and the emulsion explosive additionally granulated ammonium nitrate, which is mechanically mixed with the specified emulsion in the following ratio of components, wt.%:

Component Name Mass fraction, wt.%, Not less than for compositions Emulsion 80.00-30.00 Ammonium nitrate 18.60-65.70 Diesel fuel 1.20-4.20 Gasification solution 0.20-0.10

wherein the water-oil emulsion includes, wt.%:

Oxidizer solution Ammonium nitrate 72.00 Water 16.35 Sodium nitrate 4.00 Acetic acid 70% 0.25 Thiourea 0.25 Caustic soda 40% 0.05 Fuel solution Oil product 6.10 Emulsifier 1.00

These features are significant and are interconnected with the formation of a stable set of essential features sufficient to obtain the desired technical result.

The present invention is illustrated by specific examples of execution, which, however, are not the only possible, but clearly demonstrate the ability to achieve the desired technical result.

Figure 1 - diagram of a technological line for the production of pormemit - prototype;

figure 2 - diagram of a technological line for the production of emulsions for explosives according to the present invention.

According to the present invention, an emulsion waterproof explosive (BB) and an emulsion composition for this BB and other waterproof industrial explosive mixtures are contemplated.

Emulsion explosive contains a water-oil emulsion, ammonium nitrate, a gas-generating additive and oil products. In this, diesel fuel was used as a petroleum product in the explosive, a water-oil emulsion is based on an aqueous solution of ammonia and sodium nitrate. BB additionally includes granular ammonium nitrate, which is mechanically mixed with the specified emulsion in the following ratio of components, wt.% (Table 1):

Table 1 Name
component Mass fraction, wt.%, Not less than for compositions Emulsion 80.00-30.00 Ammonium nitrate 18.60-65.70 Diesel fuel 1.20-4.20 Gasification solution 0.20-0.10

Thus, BB includes an emulsion based on an aqueous solution of ammonia and sodium nitrate, a buffer solution, a catalyst and mixtures of oil products with emulsifiers, as well as granular ammonium nitrate, in the manufacture of the emulsion and granular ammonium nitrate are mechanically mixed in the following ratio of components, wt. %, table 2 (examples of four explosive compositions are given, in the first of which granular ammonium nitrate and diesel fuel are not used):

table 2 Component Name Mass fraction, wt.%, Not less than for compositions I-100 II-80 III-70 Iv-30 Emulsion 99.75 80.00 70.00 30.00 Ammonium nitrate - 18.60 28.00 65.70 Diesel fuel - 1.20 1.80 4.20 Gasification solution 0.25 0.20 0.20 0.10

From the data given in table 1, it follows that diesel fuel is additionally introduced into compositions II-IV, which is necessary to adjust the oxygen balance of the mixture of granular nitrate and emulsion, as well as to increase the energy performance of the explosive composition, since diesel fuel has a high heat capacity (about 41868 kJ / kg), which contributes to a more active interaction with ammonium nitrate in the explosive reaction.

The recipe provides for the content of a gas-generating additive in an aqueous solution of sodium nitrite not exceeding 100%, as is realized in the prototype and in the majority of emulsion explosive compositions used, but is taken into account in the overall balance, which allows more accurate calculation of the energy indicators of the explosive composition.

The presence of a wide range of emulsion explosive compositions provides for its use in all mining conditions during blasting operations, and when using universal mixing and charging machines capable of loading wells under a column of water (pumping through a hose with a pump) or in bulk (with a screw) , it is possible due to the difference in densities of charged explosive compositions to provide optimal conditions for the destruction of rocks to the desired fraction.

However, the recipe composition of the oil-in-water emulsion proposed in Table 3 plays the most important role in an emulsion explosive.

Table 3 Component Name Mass fraction,%, not less Oxidizer solution Ammonium nitrate 72.00 Water 16.35 Sodium nitrate 4.00 Acetic acid 70% 0.25 Thiourea 0.25 Caustic soda 40% 0.05 Fuel solution Oil product 6.10 Emulsifier 1.00 Total one hundred

The main advantages of this formulation of an oil-in-water emulsion are its properties, which allow a safe and balanced explosive composition with stable operational and explosive properties to be obtained when a gas-generating additive is added to the emulsion and, if necessary, mixed with granular ammonium nitrate and diesel fuel.

The main distinguishing feature of this composition of the oil-water emulsion from that used in the prototype is the use in the formulation of methods that help maintain the pH of the emulsion at 4-5, with the aim of producing a quick saturation of the emulsion with gas by a chemical method, carried out both at low and high temperatures without producing NOx during the process of gas formation. For the course of such an implementation, it is also provided for the use of an accelerator (catalyst) for the formation of gases - thiourea. To maintain the desired pH value of the emulsion, a buffer solution of a weak acid - acetic acid and a strong base - sodium hydroxide is used. When ammonium nitrate is replaced with 4-15% sodium nitrate, the rate of gas formation also increases, the amount of inorganic salts containing oxygen dissolved in the oxidizing solution increases, which leads to a decrease in the temperature of precipitation of crystals, an increase in the amount of oxygen supplied and, ultimately, an increase in the density of emulsion explosive compositions. Also, due to the use of sodium nitrate, a smaller amount of water is required for the dissolution of inorganic salts, which contributes to an increase in the frost resistance of a water-oil emulsion.

Mineral oils, diesel fuel and their mixtures can be used as a petroleum product to achieve an optimal emulsion viscosity of 20,000-30000 centipoise (10 ^-2 · Pa · s).

One of the most important components of the emulsion is the emulsifier used, since the stability of the emulsion depends on its effectiveness. When choosing an emulsifier, the following requirements should be observed: the correspondence of the hydrophilic-lipophilic balances of the emulsifier and the fuel solution, high emulsifying ability, long-term stability of the emulsion during storage and use. Based on these requirements, preference was given to emulsifiers Amphora and Lubrizol LZ 2820, which have an identical hydrophilic-lipophilic balance in the range of 3-6.

Therefore, the compositions II-IV emulsion explosives provide the claimed technical result - an increase in the efficiency of the explosion.

The technology (method) for manufacturing the emulsion composition for explosives proposed in the invention was developed in such a way as to exclude additional technological operations during the production process, reduce the number of equipment and maintenance personnel that is achieved using the principle of combining several technological operations in one module. The block diagram for the production of an emulsion for explosives is shown in figure 2, where the following node numbers are presented: node I - a modular capacity for preparing an oxidizer solution, with a built-in mixer and heating, node II - a modular capacity for preparing a fuel solution, with a built-in mixer and heating, node III is an emulsion preparation module, node IV is a water treatment module, node V is a gas-generating additive preparation module, and node VI is an auxiliary module with sections for storing raw materials.

In addition, the following items indicate the main units and apparatuses of the emulsion preparation line: a water tank 13, a reactor 14 for preparing a NaNO ₂ solution, a filtering unit 15 and pumping an oxidizing solution, a distribution unit 16 and pumping a fuel solution, dispersant 17, storage tank 18 for the finished product emulsions, control panel 19, heating radiator 20 and heating system 21 by means of a coolant.

The manufacturing technology of the emulsion composition according to Table 3 mainly differs from that used in world practice in that containerized modules are used as production complexes (plants), with the possibility of their operational deployment in almost any territory near the places of blasting. The technological modular complex consists of two isocestrums with a heat jacket and mixing devices mounted in them, which are used to prepare the fuel and oxidizer solutions, the container-type production module, where the main process of preparing the water-oil emulsion and its delivery to the consumer, as well as a portable diesel boiler, are carried out 22 and auxiliary sectional modules. This approach to the technology of manufacturing emulsions fully meets all the objectives of the invention.

The manufacturing technology of the emulsion composition, thanks to the use of container-type modules and the application of the principle of combining several technological operations in one module, combines safety, low power consumption, compactness, mobility of movement, minimizing staff and sufficient productivity (the annual output of a module production of an emulsion for single-shift production (8 hours) work - 7.5 thousand tons), which entails a simplification of the design and cost reduction bridges of industrial complexes.

Claims (2)

1. Emulsion composition for waterproof explosive mixtures, including an oxidizing agent solution from water and ammonium nitrate and an emulsifier, characterized in that the oxidizing agent solution comprises 70% acetic acid, thiourea as a catalyst, 40% sodium hydroxide and nitric sodium, and the emulsifier is mixed with oil to form a fuel solution in the following ratio of components, in wt.%:
Oxidizer solution
Ammonium nitrate 72.00 Water 16.35 Sodium nitrate 4.00 Acetic acid 70% 0.25 Thiourea 0.25 Caustic soda 40% 0.05
Fuel solution
Oil product 6.10 Emulsifier 1.00 2. Emulsion waterproof explosive containing water-in-oil emulsion, ammonium nitrate, gas-generating additive and oil products, characterized in that diesel oil is used as oil products, water-oil emulsion is based on an aqueous solution of ammonia and sodium nitrate, emulsion explosive ammonium explosives includes granular explosive, granular which is mechanically mixed with the specified emulsion in the following ratio of components, wt. %:
Emulsion 80.00-30.00 Ammonium nitrate 18.60-65.70 Diesel fuel 1.20-4.20 Gasification solution 0.20-0.10
wherein the oil-water emulsion includes, in wt. %:
Oxidizer solution
Ammonium nitrate 72.00 Water 16.35 Sodium nitrate 4.00 Acetic acid 70% 0.25 Thiourea 0.25 Caustic soda 40% 0.05
Fuel solution
Oil product 6.10 Emulsifier 1.00 Sodium nitrate 4.00 Acetic acid 70% 0.25 Thiourea 0.25 Caustic soda 40% 0.05
Fuel solution
Oil product 6.10 Emulsifier 1.00

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