Experimental analysis of rock mass transport during dolomite and gas outburst

Abstract

In this paper, the problem of transporting rock material deep into the working is addressed. In the case of coal, literature reports indicate that sorbed gas is responsible for coal mass transport. As a result of laboratory tests, the marginality of sorption phenomena occurring in dolomite was confirmed. Transport of rock material during rock and gas outburst takes place in several stages. In the first stage, the post-outburst masses by gravity onto the bottom of the excavation and gas is released from the cavern which, after reaching a critical speed, entrains the accumulated material. A study was carried out to estimate the minimum start-up speed for grain transport. On the basis of analyses of the occurring gas-geodynamic phenomena and the conducted experimental tests, it can be concluded that on the basis of the size of the post-throw cavity and the length of the retention of the post-outburst masses, the work of transporting the post-outburst masses can be estimated. Finally, an energy balance of the rock-gas outburst phenomenon was performed based on the rock-gas system parameters estimated after two outbursts in dolomite.