Determination of the Technological Parameters of Borehole Underground Coal Gasification for Thin Coal Seams

Purpose. Electrical equipment for explosion-threatening environments in mines at risk of explosion communicates with the external environment through intrinsic safety barriers that limit the values of currents to values below the methane ignition, limit that exceeds the allowable concentration in the atmosphere. This avoids work accidents due to under-ground explosions, avoiding the risk of explosion through electric equipment. Methods. Experimental research has been based on the geomechanical characterization of the coal and surrounding rocks in the Jiu Valley Basin and measurements obtained in situ was researched by statistic methods. Three methods of studying barriers based on the use of the MATLAB program were used. The first method is based on MATLAB programming, the second involves the barrier study using the Simulink model and the third method is based on the use of the SimPowerSystems software package. In all three cases studied, the variation of the voltage at the output of the barrier and current through the barrier are analyzed considering two operating modes, the aperiodic and the oscillating regimes. Findings. The paper is a study of the intrinsic security barriers, based on which a correct dimensioning can be made. Originality. The originality of the paper consists in the analysis of the barriers with intrinsic safety, using the simulation with the MATLAB-Simulink program packages. Practical implications. All the methods addressed lead to obtaining the diagrams of variation of the voltage at the exit of the barrier and of the current through the barrier in two possible regimes: the aperiodic regime and the oscillating regime.

Section: Figure 4 Dependence Between Permeability and Methane Flow For Coal Energymentioning

confidence: 99%

Safety barrier of electrical equipment for environments with a potential explosion in underground coal mines

Niculescu¹,

Marcu²,

Arad³

et al. 2020

“…Вели-чина температуры газификации буроугольного пла-ста изменяется по длине реакционного канала (Perkins & Sahajwalla, 2007). Максимум температур (1050 -1200 0 С) наблюдается на границе перехода окислительной зоны в восстановительную (Falshtynskyi, Dychkovskyi, Lozynskyi & Saik, 2013) Поэтому породы нижнего слоя кровли, по длине огневого канала, подвержены разным термоупругим напряжениям. Такая же ситуация наблюдается и в выгазованном пространстве (Kapusta, Stańczyk, Wiatowski & Chećko, 2013).…”

Section: определение параметров полостей расслоенияunclassified

Substantiating parameters of stratification cavities formation in the roof rocks during underground coal gasification

Falshtynskyi¹,

Lozynskyi²,

Saik³

et al. 2016

Purpose. Underground coal gasification, as a complex and technically difficult process, should be supported in many aspects by computer simulations or analytical calculations of rock mass behavior. However, little is known about the formation of stratification cavities in the roof rocks during coal seam gasification. To research the formation of stratification cavities and rocks deformations by mine pressure with the methods of calculation based on hypotheses or statistical information, a number of hypotheses are used. The main purpose is to examine the rock mass behavior and formation of stratification cavities during gasification of a thick coal seam.Methods. Analytical calculations were used as the research method for the work presented. The mathematical model of the stress-strain state of rock mass based on the theory of elasticity, resiliency, and maximum equilibrium, was developed and used in this paper.Findings. Critical analysis of geomechanical models of coal gasification together with their mathematical formulation was the result of considerations presented in this paper. Equations were derived for substantiating parameters of stratification cavities above the goaf of the underground gasifier. Subsequently, the volumes of stratification cavities depending on the length of gasification channel were calculated. The results have significant influence on gasifiers development and the final efficiency of gasification process.Originality. The research results were obtained from analytical calculations of rock mass behavior during thick coal seams gasification. The authors implemented a mathematical model based on the method suggested by professor A. Savostianov which was used in carrying out the calculations. Practical implications.The present study provides a starting point for further research and analytical calculations of rock mass behavior. The data and conclusions outlined in this paper may be useful in preliminary optimization and analysis of coal seams gasification. They can also be a point of reference for more advanced geomechanical simulations.

“…При автомобильно-железнодорожном транспорте перегрузка вскрышных скальных пород производит-ся на стационарных, полустационарных и передвиж-ных (бункерных) установках (Dryzhenko, Kozenko, Rykus, 2009). Как правило, после разгрузки порода на стационарных и полустационарных пунктах пере-гружается в железнодорожные (ж.-д.)…”

Section: анализ состояния вопросаunclassified

“…Важным фактором оценки экономической эффек-тивности принятых технических решений является прогнозирование цен на технологическое оборудова-ние (Falshtynskyi, Dychkovskyi, Lozynskyi & Saik, 2013). Как показал опыт, сроки прогнозирования не должны превышать 10 -15 лет.…”

Section: автомобильно-железнодорожный транспортunclassified

Organization of dumping stations with combined transport types in iron ore deposits mining

Шустов¹,

Dryzhenko²

2016

Purpose. To develop the methodology for selecting appropriate type of open-pit transport in conditions of mining sinking to the maximum depth of opencast mining. Findings. The proposed optimization of dumping stations placement with combined operation of automobile and railway vehicles allows to exclude utilization of dumping excavators. The efficiency of dumping stations building of block structures is confirmed which allows to decrease total number of dump trucks by 20 -30% for the average rock transportation distance of about 1.5 -2 km. The arrangement of dumping stations in the goaf on barrow benches with their further exploitation proves the possibility of effective mining of inclined and upridging deposits.Originality consists in determination of the application field for various types of open-pit transport in changing working area parameters. They are related to sinking of mining, mining intensity and formation of goaf for mining waste storage. Practical implications.The research results allow to develop recommendations for using economical types of transport in accordance with the established open-pit mining mode.