Emulsion Explosives Research Articles

The method of measuring the detonation characteristics of emulsion explosives and express determination of the strength properties of rocks

The method of measuring the detonation characteristics of emulsion explosives and express determination of the strength properties of rocks

Influence of Contaminated Ammonium Nitrate on Detonation Behaviour of Bulk Emulsion Explosives and Numerical Analysis of Detonation‐Induced Damage Zone

AbstractBulk emulsion explosives are widely used industrial explosives for mining and civil infrastructure work. Ammonium nitrate is an important ingredient for bulk emulsion explosives and plays an important role in the detonation behaviour. Considering the growing demand for bulk emulsion explosives, an in‐depth investigation is necessary to understand how the impurities in ammonium nitrate can affect the detonation behaviour and safe handling of bulk emulsion explosives. Herein, we have demonstrated the influence of contaminated ammonium nitrate on the detonation behaviour and characteristics of bulk emulsion explosive. Furthermore, the particle size of the internal phase of the all prepared bulk emulsion explosives was analyzed using optical microscopy to confirm the effect of contaminated ammonium nitrate. Time dependent chemical‐induced gassing behaviour and detonation velocity of prepared bulk explosive samples were also studied. Importantly, numerical modeling was used to stimulate the detonation‐induced rock damage zone and assess the impact of ammonium nitrate contamination. Additionally, a real‐time rock damage pattern of different prepared samples was further investigated to understand the impact of contamination on the detonation induced crack development phenomena of different bulk emulsion samples.

Thermal Safety Study of Emulsion Explosive Matrix under the Coupled Effects of Environmental Pressure and Bubble Content with Internal Heat Source

Emulsion explosives have become a hot topic in various studies due to their explosive combustion characteristics and detonation performance under different environmental pressures. The thermal safety of an emulsified matrix was studied with ignition energy as the characterization. A minimum ignition energy test experimental system for emulsion matrices was established in this research. The system simulated the occurrence of hot spots inside emulsion matrices using an electric heating wire. The effect of bubbles on the thermal safety of the emulsified matrix was studied by adding expanded perlite additive to the emulsified matrix. This study investigated the variation trend in the minimum ignition energy of the emulsion matrix under the coupled effect of bubbles and ambient pressure using the orthogonal experimental method. The impacts of two factors on the thermal safety of the emulsion matrix were studied at different hot-spot temperatures. Coupled analysis experiments were conducted on emulsion matrices containing 0%, 1.5%, and 3% expanded perlite under pressure environments of 1 atm, 2 atm, and 3 atm. The critical hot-spot temperature of the emulsion matrix significantly decreases with increasing bubble content at 1 atm and 2 atm pressures, as revealed by intuitive analysis and analysis of variance. However, at 3 atm of pressure, the bubble content in the emulsion matrix has no significant effect on its critical hot-spot temperature. The results show that the thermal safety of the emulsified matrix decreases with the increase in the content of expanded perlite and environmental pressure, and the influence of environmental pressure is more significant than that of the bubble content. This paper’s research content serves as a reference for a safe emulsified matrix and as an experimental basis for establishing a production line for developing new equipment.

Матрица бизнес-выгод как инструмент исследования потенциала цифровизации на примере мини-завода для производства невзрывчатых компонентов эмульсионных взрывчатых веществ

Modern business solutions set a trend towards integrating digital technologies into all areas of corporate organization. Digitalization plays a key role in modern business, enabling companies to increase the process efficiency, reduce costs, and improve product quality and maintenance efficiency. It also helps to be competitive in the marketplace and adapt to changing customer demands. In order to maximize the effects of implementing digitalization, the transformation needs to encompass not only the local business processes and business models, but also the corporate culture. The study analyses the process of exploring the digitalization potential for a modular mobile plant (mini-plant) that produces non-explosive components of emulsion explosives developed by AZOTTECH. The paper identifies the key points necessary for successful implementation of the digitalization process at the mini-plant, which can serve as a basis for designing a digital twin implementation strategy. It also describes application of a modern approach in performance evaluation using the matrix of business benefits.

Experimental Study for the Matching of Explosives and Rocks Based on Rock Hydrophysical Properties

The study of the hydrophysical properties of rocks is indispensable for the development of hydraulic engineering, especially for blasting operations in water. Reasonable matching between explosives and rocks increases the utilization of explosive energy and improves the blasting performances. Based on the energy law in the rock blasting process, the matching relationship between explosives and rock is studied by combining experimental and theoretical methods for the hydrophysical properties of the rock itself. Firstly, the theoretical solutions for crushing-zone energy, fragmentation energy and fragment-throwing energy are derived. Subsequently, concrete blocks are prepared with four types of cement–sand ratios, and four types of emulsion explosives are used to carry out single-hole blasting tests in which a high-speed camera is used to capture the trajectory of the blasting fragments that are later collected. Finally, the crushing energy, fracturing energy and fragment-throwing energy are calculated according to the test results and the basic parameters of the used explosives and concrete models. The results show that the size and distribution pattern of blasting blocks are significantly affected by the hydrophysical properties of concrete and explosive properties; the higher the energy consumption in the rupture zone, the smaller the size of the fragments and the more uniform the distribution. Moreover, the median utilization efficiency of explosive energy on rock breaking is 26.4%, the energy consumption in the crushing zone is approximately 8.4%, that in the rupture zone is approximately 10.9%, and that in the throwing energy of fragments accounts for approximately 7.1%. It is also found that the traditional wave impedance matching theory fails to obtain the best explosive energy utilization. On the contrary, the concrete specimen had the best fracturing effect and the highest energy utilization of 30.77% when the impedance ratio of concrete to explosives is 1.479.

Mechanism of hot‐spot formation of emulsion explosives sensitized by hydrogen‐storage glass microballoons

AbstractIn order to investigate the primary factors influencing hot‐spot formation in emulsion explosives sensitized by hydrogen‐storage glass microballoons (GMBs), we conducted impact calculations on hydrogen‐storage GMBs. The calculations focused on tracking two main mechanisms: the brittle collapse of GMBs and the adiabatic compression of internal gas. Various parameters were considered, including loading pressures, initial porosities, gas types, and initial gas pressures. Our findings indicate that the contribution of brittle collapse to hot‐spot formation is negligible, while adiabatic compression emerges as the predominant intrinsic mechanism for hot‐spot ignition in GMB‐sensitized emulsion explosives. Moreover, we observed that the ignition time remains similar for low‐pressure nitrogen and high‐pressure hydrogen. The addition of hydrogen does not result in an increased number of hot‐spots; however, it elevates the energy of each individual hot‐spot, thereby enhancing power delivery. Optimal selection of GMB size is crucial for hot‐spot formation and hydrogen storage. GMBs that are excessively large are prone to shell breakage, while overly small GMBs have limited hydrogen storage capacity. GMBs within the size range of 20 μm to 100 μm are deemed more suitable for emulsion explosives.

Разработка технологии регенерации некондиционных эмульсионных полуфабрикатов промышленных взрывчатых веществ

The research is aimed at improving the methods to produce and apply in the mining industry energy-intensive emulsions based on concentrated solutions of inorganic salts (nitrates), which are second-class dispersions of the "Water-inOil" type. Every year when mining useful minerals, surface and underground operations consume about 1.15 million tonnes of industrial emulsion explosives (IEE), the largest share of which are the so-called caseless pouring types. When the emulsion matrix is produced, it is possible that off-grade emulsion, i.e. emulsion that does not meet the requirements of the relevant normative and technical documentation, may also be generated. Tentatively, the volume of such production waste may reach 57.5 thousand tonnes per year. Therefore, the issues of reclaiming the off-grade emulsion semi-finished products of industrial explosives into initial products for their reuse is not only of scientific and technical interest, but also of great economic and ecological importance. The objective of this study, performed by employees of AZOTTECH LLC in cooperation with the D. I. Mendeleev Russian University of Chemical Technology, is the development of a method and industrial technology to recycle emulsion production wastes for re-use of the reclaimed materials in production. A chemical method of controlled emulsion destruction was obtained based on the results of the performed research activities. The most effective demulsifier available in the Russian market was selected, by means of which it was possible to separate the emulsion into immiscible phases containing the initial components. Samples of the stable emulsion matrix that match the requirements of the normative documents in terms of quality, were obtained using the oil phase reclaimed materials and the oxidant solution.

Effect of internal phase particle size on properties of site mixed emulsion explosive at plateau environment

To study the effect of internal particle size on the microstructure properties and thermal decomposition characteristics of site mixed emulsion explosive at different altitudes. Site mixed emulsion explosive was prepared with different shear rate. The particle size, viscosity, sensitized bubbles, detonation velocity and peak pressure of the emulsion explosive were tested after stored at different simulated altitudes. The thermal decomposition characteristics of emulsion matrix prepared at three different rotational speeds were measured by thermogravimetric analyzer and kinetic analysis was performed by non-isothermal model Kissinger–Akah–Sunose (KAS) method. The results show that with the increase in altitude, the internal phase size showed a trend of first increasing and then decreasing, and the number of sensitized bubbles within the emulsion explosive decreases. At an altitude of 0 m, the detonation velocity and peak overpressure of the emulsion explosive prepared by 1600 r min−1 increased 4.78% and 29.09%, respectively compared with 1200 r min−1, and at an altitude of 4500 m, the detonation velocity increased 11.87%, the peak overpressure increased 43.98%. The thermal decomposition activation energy of the emulsion matrix at 1600 r min−1 increased 13.14% compared to 1200 r min−1. It shows that in the production of site mixed emulsion explosive at high altitude, reducing the particle size of the internal phase of emulsion explosives in a certain range can effectively improve the performance of emulsion explosives.

SPH numerical simulation of SC-CO2 directional fracturing and emulsion explosives for rock breaking

SC-CO2 (Supercritical carbon dioxide) directional fracturing is a promising alternative to explosive blasting in complex environments. This study aims to establish an equivalent method for directional fracturing using traditional explosives, promoting broader adoption of this technology. We conduct a comparative experiment analyzing explosive and SC-CO2 rock breaking, developing the SPH (Smoothed Particle Hydrodynamics) numerical model that includes characteristics of the rock-breaking area and dynamic effects of SC-CO2 and explosives. Additionally, we investigate the influence of the directional fracturing device on the energy release coefficient. Proposing a numerical simulation method for SC-CO2 directional fracturing based on equivalence to No.2 rock emulsion explosive, we use the SPH particle algorithm to enhance visualization of the rock-breaking area. Our findings show that the explosive method yields a larger rock-breaking volume than SC-CO2. Under identical explosive charges, the directional cracker model inhibits explosive energy release, with energy decreasing as distance increases. Calculating an inhibition coefficient of 0.45 for the cracker model in terms of explosive granite, the rock-breaking volume index is 0.48, with an average value of 0.465. In mudstone sites, a similar trend is observed with an average energy release inhibition coefficient of 0.44.

Effect of TiH2 Particle Size on Properties of Emulsion Explosive

Effect of TiH2 Particle Size on Properties of Emulsion Explosive

Raises advance using emulsion explosives

Using the well-known laws of the theory of elasticity and the basic principles of the quasi-static wave hypothesis of the mechanism of destruction of a solid medium by an explosion, methods have been developed for calculating the parameters of drilling and blasting (D&B) for raises advance using the methods of blast-hole and borehole charges. It has been established that the calculating D&B parameters is carried out in the same sequence as when drifting operation. To check the calculating D&B parameters using the new method during raise advance, a numerical simulation of changes in the stress-strain state of a rock mass under the influence of an explosion was carried out. According to the results of numerical simulation, the formation of zones of inelastic deformation in the face of a rising mine working under blast load, uniform grinding of the rock was obtained, which will avoid the release of oversized pieces after the explosion. The developed methodology was tested in the conditions of the “Yuvileina” mine of PJSC “Sukha Balka” during the raise advance of a 1420 m level using a sticked emulsion explosive (EE) Anemix P. Test explosions obtained good results in blasting the face of a raise, uniform crushing of the rock and a high coefficient of use of bore-holes has been established.

The effect of blasting using low-density emulsion explosives

The effect of blasting using low-density emulsion explosives

Corrigendum: A case study to improve blasting efficiency by the use of emulsion explosives (Oil Shale, 2023, Vol. 40, No. 3, 244–259)

Corrigendum: A case study to improve blasting efficiency by the use of emulsion explosives (Oil Shale, 2023, Vol. 40, No. 3, 244–259)

Обоснование выбора способа изготовления и доставки эмульсионных взрывчатых веществ при внедрении нового технологического уклада на мощных угольных разрезах Кузбасса

The sphere and conditions for application of the water-in-oil type of emulsion explosives in deposits of the Southern Urals and Kuzbass have been justified. Two sub-classes of these types of emulsion explosives are defined depending on the main components used at the final stage of their production (a blast hole or mixing and charging machine) with or without addition of dry ammonium nitrate. Diagrams of semi-stationary and mobile technological complexes have been justified for production of emulsion explosives. A rationale was provided for the selection of the competing methods to produce and deliver emulsion explosives using the case of UK Kuzbassrazrezugol JSC with account of technological and economic factors. Three competing options were considered: (1) a stationary or semi-stationary technological complex to produce emulsion explosives; (2) a stationary technological complex based on the existing plant of Nitro Siberia-Kuzbass JSC (Kemerovo) under an outsourcing agreement; (3) a mobile technological complex as a case of partial outsourcing to the Nitro Siberia-Kuzbass JSC plant. Comparison of the competing options helped to identify the third option as the priority. In this option the cost of emulsion explosives is affected by the cost of basic components at the chemical plant; depreciation of the self-propelled component delivery vehicles (10-15 vehicles); operating and maintenance costs of the delivery vehicles; rental of the mixing and charging machines (1-2 vehicles) to produce and charge the emulsion explosives. After covering the capital expenses (1-1,5 years) there will be a reduction in cost up to 20% as compared to the second option.

Experimental study on the effect of titanium hydride content on the detonation performance of emulsion explosives

AbstractIn order to improve the explosion characteristics of emulsion explosives, titanium hydride was added to emulsion explosives to produce a new type of hydrogen storage emulsion explosives. Charges with different contents of titanium hydride were evaluated through underwater explosion experiments and detonation velocity tests. The tests on underwater explosion and detonation velocity reveal that compared to pure emulsion explosives, the detonation parameters of emulsion explosives containing titanium hydride showed a trend of first increasing and then decreasing. When the mass ratio of titanium hydride in the emulsion explosive is 1 % to 3 %, all detonation parameters have been improved to a certain extent. When the mass ratio of titanium hydride in the emulsion explosive is 3 % to 10 %, only part of the detonation parameters (specific impulse, specific shock energy, specific total energy and volume energy density) has been improved. The maximum increase of specific impulse, specific shock energy, specific total energy and volume energy density of emulsion explosive containing titanium hydride is 7.06 %, 8.95 %, 3.97 % and 8.22 %, respectively. Based on the analysis, it is evident that though powdered TiH2 participates in the detonation reaction process of the emulsion explosive, the majority of TiH2′s energy is released during the secondary reaction occurring after the detonation wave front. Therefore, the detonation performance of emulsion explosives can be effectively improved by adding a certain mass ratio of titanium hydride.

Using the methods to calculate parameters of drilling and +blasting operations for emulsion explosives

Mathematical modelling of rock mass breaking using blasting has been applied to obtain formulas for the calculation of crush zone radii, intensive fragmentation, and crack formation around the charging cavity in the structure, diameter of the charging cavity, diameter of the charge itself, detonation characteristics of an explosive, boundaries of the rock strength, rock mass jointing, and mineral compression under the effect of rock pressure. The methods have been developed to calculate parameters of drilling and blasting operations (DBOs) while driving the mine workings based upon the idea of the arrangement of blastholes in terms of areas they occupy in a fore-breast as well as upon their location relative to break-off outline. Stage one of the methods involves calculating and designing burn cuts where a distance between blastholes is determined with the help of a fragmentation zone radius. Stage two means calculation of both specific and total explosion consumption per borehole bottom, line of least resistance (LLR) for a borehole in terms of intensive fragmentation, areas of borehole groups, borehole number, analytical and actual distance between boreholes, actual charge amount per borehole, and actual specific and the total explosive (E) consumption per borehole bottom. The methods have been tested in the operating ore mine while driving a mine working. Emulsion explosive (EE) Ukrayinit-PP-2 (Україніт-ПП-2) has been applied. The developed methods have been used to calculate DBOs parameters for the explosive. Trial blasts demonstrated the good firing of a borehole bottom and uniform ore fragmentation; a high coefficient of borehole use has been supported.

Safety considerations of static sensitization emulsification technology for Kings-type emulsion explosives based on quadratic linear programming algorithm

Abstract This paper collects data on the static sensitization emulsification process flow of Kings-type emulsion explosives, analyzes the collected data by combining the indicator factors and probability density functions in the time-domain analysis, and designs a safety monitor for the static sensitization process flow. In order to pursue more rigorous production safety, the static sensitization process optimization objective function was determined, and the function was constrained as well as quadratically linearized to construct a static sensitization process safety optimization model based on quadratic linear programming. After analysis, it is concluded that the safety factors affecting the static sensitization process are temperature, sensitizer, number of sensitizer stages and pressure. Other conditions are the same, the foaming density can finally reach 1.23g/cm 3 when low-temperature static sensitization, but the time spent is longer 14h, and the foaming density decreases from 1.41g/cm 3 to 1.09g/cm 3 as the amount of sensitizer increases.

Thermal decomposition characteristics and spontaneous combustion phenomenon of emulsion explosive containing FeS2 impurity

AbstractIn the process of pyrite blasting mining, emulsion explosives in blast holes can sometimes spontaneously detonate prematurely. In order to reveal its accidental explosion mechanism, the effects of different content of FeS2 impurity on the thermal decomposition characteristics and thermal spontaneous combustion parameters of emulsion explosives were studied in detail. The experimental results of thermal analysis showed that pure emulsion explosive had a strong stability, but when it was doped with FeS2 impurity, its initial temperature of thermal decomposition reaction reduced and the decomposition rate accelerated. With the increase of FeS2 impurity content, the average activation energy of emulsion explosives decomposition decreased from 110.84 to 63.78 kJ/mol, resulting in an increasing risk of thermal runaway. The results of thermal spontaneous combustion experiments showed that FeS2 impurity would significantly shorten the ignition delay period and combustion flame duration of emulsion explosive, and increase the combustion flame temperature. With the increase of FeS2 impurity content in emulsion explosive, the ignition delay period and the duration of the flame continued to decrease and increase, respectively, and the maximum average temperature of the flame showed a trend of rising at first and then decreasing. The research results were of great significance to the accident identification of emulsion explosive accidental explosion in pyrite blasting operations.

BENEFITS AND LIMITATIONS RELATED TO THE APPLICATION OF THE REACH REGULATION FOR MINING EXPLOSIVES

The article outlines practical implications associated with the development and implementationof the REACH regulation. Following the introduction of this legal act, the system for managingthe safety of chemical substances throughout the European Union has been harmonised andbased on the principles of registration, evaluation and authorisation. These rules apply to alltypes of substances, preparations and products available on the market. Their importance inreducing the environmental impact of hazardous substances, including explosives, should beconsidered particularly important. The study inter alia analyses the advantages of applying theREACH system to mining explosives (dynamites and emulsion explosives), including in particulara comprehensive analysis of the environmental effects of the use of this type of substances, carriedout according to unified criteria specified in the provisions of the regulation. On the other hand,the major drawback of the adopted regulations is the failure to take into account the conditionsassociated with the safety of the working environment in the discussed legal act.

Влияние качества аммиачной селитры на свойства эмульсионных взрывчатых веществ

Emulsion explosives are widely used in the mining industry, and their use, in combination with modern means of initiation, has improved the safety of mining operations and significantly increased labor productivity. The main component of emulsion explosives is ammonium nitrate, which is part of the emulsion matrix. Grade A is produced for the industrial purposes, while Grade B is used in agriculture. Due to difficulties in logistics, mining enterprises that produce emulsion matrix often use Grade B ammonium nitrate. The main disadvantage of ammonium nitrate is its high water absorption capacity. Caked ammonium nitrate loses its properties, becomes unusable and cannot be utilized in preparation of the emulsion matrix. In order to slow down the caking process, special additives are introduced into the composition of Grade B ammonium nitrate. The paper presents the research data on the material composition of ammonium nitrate of Grades A and B as well as its influence on the physical properties of the obtained emulsion matrix. To identify differences in the physical properties of the emulsion matrix obtained from ammonium nitrate of Grades A and B, studies of the dynamic viscosity and electric capacitance of emulsions were carried out, and the detonation velocities of emulsion explosives charges were measured. It has been established that Grade B ammonium nitrate contains sulfates, exceeding the threshold values of which can lead to partial or complete stop of detonation of the emulsion explosive; dynamic viscosity and electrical capacitance of the emulsion matrices with Grade B ammonium nitrate are characterized by low rates; the detonation rate of the charge prepared using Grade B ammonium nitrate is 7–10% lower than the detonation rate of the charge based on Grade A ammonium nitrate.