Parameters of preventive gas removal from mine bedrocks during the layer mining of the Third potash formation at mines of Belaruskali JSC

The article presents results of studies aimed to develop parameters for preventive gas removal of mine bedrocks occur during the layer mining of the Third potash formation in conditions of Belaruskali JSC mines. Development of parameters for preventive gas removal of bedrocks was carried out based on results of mine experimental studies of gas content, gas dynamic characteristics of bedrocks and experimental studies of dynamics of pressure of free gases under different mine industrial conditions of layer mining at the Third potash formation. A method of mine experimental research consider quantitative assessment of the indicators such as gas content of bedrocks on free gases, initial velocity of gas emission from bedrocks, pressure of free gases of bedrocks. Study of dynamics of change in time of pressure of free gases in bedrocks of the preparatory excavations were carried out in excavation poles of long faces that mine layers 2, 2-3 and 3 of the Third formation. That was done with help of measuring stations (packers) equipped for measuring the pressure of free gases in the measuring chambers by digital manometers. Based on results of mine experimental studies, regularities of formation of focuses of gas dynamic phenomena in bedrocks were established. Regularities consider various mining conditions of layer operation of the Third potash layer. Parameters of preventive gas removal drilling of wells into the bedrocks of preparatory excavations for long faces that mine layers 2, 2-3 and 3 of the Third potash layer in various geological and mining conditions have been developed. Parameters consider established regularities of formation of focuses of gas dynamic phenomena in bedrocks. Parameters of preventive gas removal drilling for various technological schemes for operation of the Third layer include a list of excavations in the long faces where preventive gas removal drilling should be applied and diameter, depth and distance between the degassing wells. Introduction of schemes of preventive drilling of degassing wells into the bedrocks of preparatory excavations of long faces that mine layers 2, 2-3, 3 of the Third potash layer allows to increase safety of mining operations at the mines of Belaruskali JSC.