Optimization of blast design to improve blasting efficiency

Abstract

Blasting efficiency in quarry operations play a crucial role in achieving optimal fragmentation, reducing secondary breakage, minimizing operational costs and environmental impacts. The study focused on optimizing blast design at Roko Quarry Mines using advanced software tools such as Wipfrag and O-pit Blast to enhance fragmentation outcomes. Wipfrag enables accurate fragmentation analysis by assessing the particle size distribution, D20, D50, D80, D90 and many others, while O-pit Blast facilitates precise blast design optimization for improved results. Poor fragmentation, characterized by oversized boulders exceeding the desired 200-600 mm range increase secondary breakage costs and affect the downstream processing efficiency and productivity. Fragmentation refers to the process of breaking down solid in-situ rock masses into smaller pieces during excavation/ material handling operations. This study focused on optimizing blast design to enhance blasting efficiency at Roko Quarry Mines in Mukono district. The study involved analyzing the current blast design parameter values to identify factors affecting blasting efficiency, optimizing blast design parameters, and testing the effectiveness of the optimized blast design parameters. The study refined parameters, including burden, spacing, powder factor, sub drilling length, explosive quantity, stemming length, and burden-spacing-ratio to achieve more uniform fragmentation by integrating with advanced blast design fragmentation and optimization software solutions. A Comparative analysis of pre-and post- optimization fragmentation results provided insights into the effectiveness of software-driven blast design improvements. The findings contributed to formulating best practices for optimizing blasting efficiency at Roko Quarry Mines and other similar operations.