Exploration drilling for pre-mining gas drainage in coal mines

Abstract

High natural gas content in coal seams and low gas drainage efficiency are the basic issues to be addressed in order to ensure coal mining safety. A great number of wells being drilled within various gas drainage techniques significantly increase the costs of coal mining and do not reduce the gas content levels within the coal beds up to the required parameters in a short period of time. The integrated approach toward exploration well spacing applied at the stage of project development could make it possible to consider coal seam data to provide more effective gas drainage not only ahead of mining but also during further gas content reduction and commercial production of methane. The comparative analysis of a closely spaced grid of exploration program compiled in accordance with the recommendations on applying mineral reserves classification and inferred resources of coal and shale coal deposits and currently effective stimulation radius proves the necessity and possibility to consider exploration well data for gas drainage. Pre-mining gas drainage could ensure the safety of mining operations.