Abstract
<title>Abstract</title> <p>Facing persistent economic pressures, the global mining industry must optimize its most energy-intensive process, comminution. Conventional approach dictates that finer rock fragmentation from blasting reduces downstream crushing costs. This study challenges that paradigm by demonstrating that strategic coarsening of fragmentation through widened blast patterns can yield significant net cost savings across the integrated mine-to-crusher value chain. Through a rigorous empirical case study at a large-scale gold mine, three blast geometries were evaluated: a 4.0 m × 4.0 m baseline, a 4.0 m × 4.5 m intermediate pattern, and a 4.5 m × 4.5 m widened pattern. As anticipated, wider patterns reduced drilling and blasting costs by 4% due to fewer holes and a lower powder factor. Crucially, the subsequent coarsening increased primary crushing energy costs by 15%. The innovation of this research lies in the holistic cost analysis that integrates these opposing cost streams. Counter-intuitively, the 4.5 m × 4.5 m pattern delivered the lowest total cost, with a net gain of 11% over the baseline. This finding proves that the traditional pursuit of maximal fineness is not universally optimal. Instead, a systems-level approach that leverages controlled coarsening of fragmentation can strategically reallocate costs and unlock substantial economic value. This work provides a practical, data-driven framework for mines to enhance sustainability and resilience by optimizing the entire drill-to-crush sequence, demonstrating that true efficiency comes from holistic optimization rather than isolated process improvements.</p>