The Phoenix secondary crusher installation has been successful with grinding energy consumption decreased significantly (15-20%) against a modest increase in crushing energy. Phoenix is a fascinating case study as the approach taken is different to what has typically been done and what is recommended for precrushed SAG mill feed. This is a teaser of for the full paper to come later this year!
OPERATIONAL EXPERIENCES AND PERFORMANCE ASSESSMENT OF SECONDARY CRUSHING PRIOR TO SAG MILLING AT NEWMONT’S PHOENIX OPERATION
C. Bissue1, B.Olson1, R. Tucker1, K. Tempel1, W. Hunter1, A. Giblett2
1Newmont Mining Corporation Phoenix Mine- Battle Mountain
2Newmont Mining Corporation Newmont Metallurgical Service Denver
Due to a combination of extreme and variable ore hardness, the Newmont Phoenix Operation has not consistently met throughput expectations via a conventional SABC circuit since the process plant was commissioned in 2006. Detailed analysis determined that optimizing the existing grinding circuit would not realize sufficient improvement to allow target throughput levels to be achieved. Further simulation and plant trials indicated the potential of increasing the mill throughput to the desired levels by reducing the SAG mill feed size.
In August 2012, the Newmont Phoenix Operation upgraded the process facility to allow full secondary crushing of the SAG mill feed. The operation also installed two additional trains of flotation cells to accommodate higher throughput levels in flotation. The installation has demonstrated a positive impact on plant throughput and has reduced the influence of variable rock hardness on plant performance. This paper discusses the operational experience and the results of the secondary crushing installation on plant performance in detail, including mill throughput, energy efficiency and grind size.