Drilling and blasting are fundamental operations in the mining cycle and consti tute an important component of the mining costs. Rock fragmentation can in principle be managed by means of two options: by increasing or reducing the specific consumption of explosives, or by modifying the drilling pattern. The choice of one or other type of control depends on the relationship between the unit costs of drilling and explosives, and on technical restrictions or regulations imposed by different reasons. It is then necessary to identify the link between the blast design and some factors affecting the downstream processing of the product. This paper analyzes the theoretical basis aimed at evaluating the main parameters involved when organizing a production blast in open pit quarries. In particular, a method developed through the analysis of the results in a large number of limestone open pit quarries in Italy is described and commented. The first experimental results in Brazil have been obtained by applying this method at the Experimental Mine of the Research Center of Responsible Mining of the University of São Paulo. Experimental methods and results will be analyzed and discussed in the second part of this paper.
Drill & blast; bench blasting; bench blasting; rock fragmentation; downstream processing; KPIs
