Blasting efficiency in granite aggregate quarry based on the combined effects of fragmentation and weighted environmental hazards

Abstract

Purpose. Mine and quarry operators determine blasting efficiency by the sizes of fragments, while regulatory agencies evaluate the same from the level of environmental discomfort. Thus, a conflict of interest exists. This research distinguishes fragmentation efficiency from blasting efficiency. It proposes a new approach for evaluating blasting efficiency to break the conflict of interests between the quarry operators and the regulatory agencies. Methods. Five blasting events in the FYS granite aggregate quarry have been studied, and design parameters have been obtained. As an indicator of blast-induced environmental discomfort, vibrations and air blasts are measured using a seismograph. The WipFrag desktop and Kuz-Ram model are used to assess the resulting fragmentations. Blasting efficiency is evaluated as a function of fragmentation and environmental constraints. Findings. The powder factor affects the fragment size distribution and the environmental hazards of blasting but in a conflicting manner. Increased powder factor enhances good fragmentation but results in further environmental discomfort. Blast event 4 has the highest fragmentation efficiency of 46.53%, while 3 has the highest environmental control efficiency of 69.47%. Cumulatively, blast event 4 has the highest overall blasting efficiency of 45.43%. Future research is expected to standardise this novel approach and incorporate more blasting effects. Originality. This work is the first attempt to quantify the efficiency of blasting operations in the aggregate quarry by combining the fragmentation produced and the resulting environmental hazards in a single model. Practical implications. The model proposed in this research can be adopted by quarry operators and regulatory agencies for sustainable quarrying and mining to address identified conflicts of interest between them.