Specific energy as a criterion for the use of rapid excavation systems in Turkish mines

Mechanical miners, such as roadheaders, continuous miners, impact hammers and tunnel-boring machines, allow continuous operation and it is, therefore, to be expected that mechanization of mines by the introduction of such equipment will increase productivity, decrease production costs and improve competitiveness. As part of a research project supported by the Turkish Government, a review of Turkey's mining industry in terms of reserves, production, exports and imports was undertaken and the parameters influencing the applicability of rapid excavation systems were then assessed. Many mine visits were made to gather information. Eleven large samples of rock block, including chromium ores, copper ores, harzburgite, serpentinite, trona, celestite, anhydrite and gypsum, were collected from some of these mines and subjected to full-scale laboratory cutting tests with a conical cutter at Istanbul Technical University; the data from these tests were then used to assess cuttability and estimate performance/production rates. An equation was developed to predict the optimum specific energy and, thus, the production rate. A case study of the potential for mechanical miner application was performed for a chromite mine on the basis of an analysis of the operational conditions and rock mass properties of the orebody, such as geometry, jointing, foliation, cuttability and abrasiveness. The results indicate that the introduction of mechanical miners at some mines in Turkey would be technically viable and efficient.