Mining to greater depths, into more difficult mining-geological conditions, leads to increased accident risks associated with downtime, damage or loss of mining process equipment, and injuries and victims of mining workers. In recent years, “Integrated program for the phased elimination of unprofitable mines, located in the territory of cities of Prokopyevsk, Kiselevsk, Anzhero-Sudzhensk, and relocation of residents of undermined areas” is carried out. The Program includes 12 mines; at that, some of them are town-forming. For the extraction of the remaining reserves it seems to be promising to use technologies involving thermal processing of coal in the place of its occurrence using the technology of underground gasification of coal. The economic efficiency of underground gas generator depends on many factors: geometric, technological, and engineering parameters, grade of coal, its physical and chemical properties that in varying degrees characterize the indicators of a material balance of coal combustion process in underground conditions. For a specific type of coal, approaches to calculation of indicators of material balance in coal combustion have been developed. However, reliable data about non-conforming stocks and stocks in the low layers are virtually absent. The article is devoted to the development of the scheme of calculating the material balance of coal combustion in underground conditions, when there is no required amount of input data. The analysis of existing approaches has been fulfilled; their strengths and weaknesses have been identified. The ratio between the volume of dry air, the volume of combustion products, and the amount of water vapor with the heat of coal combustion and with the account of grade composition has been obtained. Analysis of the accuracy of calculations of combustion products volume obtained by the formula based on the data of field experiments showed that the average error in the calculations is 1.5%, and the largest does not exceed 5%. The calculated scheme can be used in the calculation of indicators of material balance of the combustion process of coal in underground conditions for liquidated mines in accordance with “Integrated program”.
The paper presents the development of an adequate mathematical model of a two-drive belt conveyor with tensioning device, complemented by the model of the controlled electric drives of the belt conveyor, and also the simulation results that allow to determine the speeds and tensions at characteristic points of the belt conveyor model, which will make it possible to synthesize the speed control system of the conveyor belt if there is no slipping on the drive drums at any conveyor speed. Mathematical model allows observing transient processes of an object at various modes of operation of conveyor belt motion and the model of tensioning device. Transient processes on the velocities of the concentrated masses of the conveyor belt motion model were obtained by computer simulation. Computer simulation of the developed system was carried out using Simulink software.
Control over the state of the dust environment in the mine workings is currently an urgent task. In this publication the analysis of coal mine dust control hardware is fulfilled. Currently, there are several ways to determine the mass of the dust sediment in the conditions of mine workings, they are treated as indirect and direct methods. The study made it possible to classify methods of measuring the mass of dust sediment by the criterion of measurement error. It should be noted that the accuracy of indirect methods of measuring the mass of the dust sediment is large enough and can reach 60% in some cases, so the most promising are the methods of direct measurement. These methods include gravity and radioisotope. The publication discusses the said methods in detail; schematics for the possibility of constructing modern devices of dust control are introduced.
Coal industry in Russia currently works in significantly complex conditions. This has an impact on enterprises profitability and actualizes the use of modern means of coal mining with the purpose of cost reduction. The present article examines the problems of “manless coal winning” technology development in conditions of underground mining. The functioning of the introduced structure is possible on condition of the main equipment electric drives system modernization by means of transferring them from uncontrolled mode to control mode. It should be noted that the introduced structure will allow increasing the level of industrial security in shafts prone to sudden outbursts of gas and dust.
Mining activity transition into deep depths and intensification of minerals production processes increase the risks of emergencies due to various dynamic manifestations. In these conditions the use of technologies which provide thermal coal processing in its position with the help of subsoil coal gasification seems advantageous; the use of this technology will involve into the sphere of industrial production not only balance coal reserves being wasted, but also a significant part of off-balance reserves. Contents predictability and the quality of energy producing gas depends on the correct substantiation of underground gas generators parameters. A new flowsheet of fire channel parameters theoretical calculation is suggested.
Recently the two tendencies can be traced: increase in the volume of coal production and, due to low cost of liquid hydrocarbons, increase in debt for loans and credit lines of mining enterprises. These factors make the increase in energy-efficiency level at coal production currently important due to the use of modern technologies, which will help to significantly increase the products competitive ability and the level of industrial safety at coal shafts. By the example of stoping area of Breevsky seam of “Polysaevskaya” coal mine of OJSC “SUEK-Kuzbass” the article reveals the ways of the main equipment modernization due to modern technologies in the sphere of electric drives control systems and modern systems of control over methane release at coal shaft face area, prone to sudden outbursts of dust and gas.