Informational Articles

Second-tier diamond-mining companies, i.e. Petra Diamonds Limited, Dominion Diamond Corporation, Lucara Diamond, are reviewed in the article. It describes their operating structure and diamond production performance over recent years, which gives evidences that these dynamically developing businesses in the short run will become world-leading diamond-mining companies in terms of production and sales volumes of rough diamonds.

The paper studies the issues concerned with development of seabed mineral deposits. It analyses experience in prospecting and mining mineral deposits below the ocean floor. The key nature protection requirements towards mining operations are described, and sources of negative impact on the eco-system and their consequences are analysed.

Coal remains a major component of global fuel supplies, accounting for 27% of all energy used worldwide and making up 38% of electricity generation. It plays a crucial role in industries such as iron and steel. But concerns about air pollution and greenhouse gas emissions cloud the future of coal. This paper shed the light on current and future coal production and demand in developed and developing countries.

The authors address some important aspects of industrial safety and safety-in-underground coal mining.Arguments are provided in favor of the air-gas monitoring system, which can be further perfected due to a broad-scale application of portable gas analyzers, including those incorporated in miners’ cap lamps. Application of such gas analyzers provide for underground workings scanning for harmful gases and oxygen with on-line transmission of measurement results to the control panel of a mine control operator. The authors note that the modern personnel positioning system is characterized by the optimal combination of wireless and cable communication acilities, This system identifies the coordinates of the personnel location in underground workings with high resolution – data is transmitted on-line to the control panel of a mine control operator. This allows the continuous monitoring of travel patterns and location of miners workplaces, enhances the personnel safety during work processes in underground mining conditions.

The article addresses the problems of coal-bed methane drainage efficiency and prevention of methane explosions. The authors present the analysis of the current coal bed knowledge and understanding. The existing ideas and methods of research into coal beds are described. The article also contains the analysis of the effect of vibrowaves and electromagnetic methods on coal beds. The fundamentals of the theory of the electron-wave effect with respect to coal beds are described. All physical and chemical processes going in a coal bed are based on the internal energy of coal atoms. The formation and accumulation of methane in a coal bed results from the growing rock pressure and increasing electron-wave thermal energy. Electromagnetic emission from an external source into a coal bed would enhance the efficiency of gas drainage and prevent sudden outbursts of methane.

The authors analyze the experimental evidence on the relation of gas emission rates in production faces and stress-strain behavior of the rock mass face area. Rock has been monitored by parameter of the artificial acoustic wavelet, coefficient of relative strains K and spectrum resonance frequencies. Equations for K coefficient dependence and methane concentration in the return air have been developed. The respective correlation ratios, regression equations and determination factors have been calculated.

Based on the results of health-related studies the article describes the formation and environmental pathways of harmful agents in the air of working zones in the process of development and production operations in mines operating self-propelled machinery with diesel engines. Despite relatively short time (at most 20% of a working shift) of self-propelled machinery operation in heading processes, high concentrations of exhaust components are detected also during drilling and development processes. In production stopes the level of air contamination in working zones increases in the course of a working shift. The exposure of mine workers servicing the machinery with diesel engines to dust-gas mixture in the mine air causes toxic-dust injury of bronchi.

The article discusses issues related to the history and patterns of development of belt, plate and scraper conveyors, discusses the design, analyzes the advantages and disadvantages of each of them, summarizes and draws conclusions.

The article deals with general aspects of the design and development of earthmoving, excavating and transportation machinery implements. The rationale is provided of the right choice of implement design. The effect of the shape of implements on energy intensity of a process is discussed.

The article contains a brief description of the available current methods of prevention of groundwater ingress into underground structures from watered rock mass. An exclusive construction technology is proposed for the creation of underground watertight barriers (UWB), such as groundwater dam. The author shows an opportunity of such UWB construction for the protection of the Mir underground mine run by the ALROSA Group against brines coming from the Metegero-Ichersky aquifer system. UWB volumetric parameters of 5 m horizontal thickness are given, with interval breaking of the structure height. Concept-based opportunity is also shown of the construction of underground watertight reservoirs for in-situ leaching by this method.