Mine-to-Mill Optimization of Aggregate Production

Mine-to-Mill optimization is a total systems approach to the reduction of energy and cost in mining and mineral processing operations. Developed at the Julius Krutschnitt Mineral Research Centre (JKMRC) in Queensland, Australia, the Mine-to-Mill approach attempts to minimize energy consumption through the optimization of all steps in the size reduction process. The approach involves sampling and modeling of blasting and processing, followed by computer simulation to optimize the operation and develop alternatives. The most promising alternatives are implemented, and sampling is conducted to quantify energy savings. In the current project, the primary objective is to adapt the JKMRC Mine-to-Mill technology to the aggregates industry. The second phase of this project is being carried out at the Pittsboro Quarry located south of Chapel Hill, North Carolina. This quarry is owned by 3M Corporation and operated by Luck Stone. Based on lessons learned from the first phase work, long-term monitoring ({approx} three months) of all quarry operations is being carried out to minimize the impact of geological changes during the mining process. To date, the blasting and processing operations have been audited and modeled, the long-term monitoring of current Luck Stone practice has been completed, and a modified blasting approach has been implemented based on the results of simulations using JKSimBlast and JKSimPlant. The modified blasting approach is expected to increase the primary throughput by 15% and the secondary throughput by approximately 6%, with an overall specific energy reduction of around 1%. Long-term monitoring is currently underway to evaluate the impact the modified blasting approach. This report summarizes the current status of work at the Pittsboro Quarry