Controlled Blasting at Parsa East & Kanta Basan Opencast Mines for Safe and Efficient Mining Operations

摘要

The mining industry is heading towards a technology driven optimization process, international market pressures and competitiveness ensure that this process will continue and accelerate in this century too. The development and advancement of innovative technologies are essential for the mining industry to he cost effective so that information can flow hack into the process for continuous improvement. Close on the heels the last decade has also seen a dramatic progress in the advancement of blasting technology and the quality and performance of products. Monitoring instruments, measurement technologies and computing tools now have been the capabilities of broad assumption. The performance and reliability of explosives and initiation systems are now at level that allows the distribution and sequencing of explosive energy to be carefully controlled. Blasting performance is determined by the interaction of the detonation products of an explosive and confining rock mass. Rock mass properties dominate this process. The blasting engineer is, therefore, faced with the challenge of determining which rock mass properties most influence blasting performance in each situation and of deciding how blast designs should be changed to suit different geological conditions. The measured response of residential structures is a critical indicator of troublesome or potentially damaging ground vibrations. The study involved 22 blasts, employing signature hole blast to production blasts. The bench height varied from 4 m to 6 m, and boreholes were loaded with SME explosives and in few blasts with cartridges explosives. The number of holes varied from 22 to 63 at overburden benches whereas in coal benches 14 to 21 holes were fired in a blasting round. The total explosive weight fired in a round varied between 250 kg to 1575 kg and the explosive weight per delay also varied from 24 kg to 95 kg. The quality test of nonel tubes were performed and in-the-hoie VOD of explosives were tested for optimisation of blast design. The delay timing between the rows were optimised in view of proper rock face movement by performing signature blast in the overburden bench to avoid the overlapping of blast vibration waves and accordingly blast designs were optimised which yielded desired blast results.