Determination of the suitable slice thickness for gaining coal in goaf in Ömerler underground mechanized mine

This research was carried out in order to determine the suitable production period or cycling for the start of coal gaining from the goaf in a mechanized production system of Ömerler underground coal mine. The unexcavated part of the coal seam (roof coal) is obtained from the goaf area as a back coal since the seam being worked is very thick and the current production method applied do not allow the excavation of the whole seam thickness. This method necessitates the selection of proper support system which allows the unexcavated part of the coal seam (roof coal) to be obtained from the goaf area. The thickness of the roof coal in Ömerler underground coal mine is very high. Therefore, coal gaining from the goaf becomes very important in this production method.In this research, it was aimed to reach a suitable production cycling for coal gaining from the goaf which enables higher rate of recovery from the collapsed roof coal in the goaf, increased safety due to the less amount of roof coal left in the goafand lower stone dilution rate in the back coal obtained. For this purpose, coal wining was initiated after single, double and triple face cuts and the data for each case were collected. The data were then interpreted and comparisons were made. The best results were obtained in the case of back gaining after triple face cuts were achieved.Keywords: Coal in Goaf, Production Period, Mechanized, Support Systems, U/G Coal Mining, Roof Coal, Excavation, Underground.