*S. ESEN1, M. DANIEL1, B. DZHALOLOV2, B. BACHRAMOV2, J. GERONIMO2, & A. KALMATAYEV2
1Esen Mining Consulting Pty LtdSydney, Australia2JSC AK AltynalmasAlmaty, Kazakhstan (*Corresponding author:
SAG Conference Vancouver, Canada September 22 – 26, 2019
ABSTRACT
JSC AK Altynalmas engaged Esen Mining Consulting Pty Ltd (EMC) to conduct a drill-to-mill plant optimization project to determine what opportunities exist to increase the mill throughput and improve the overall mine and concentrator performance. The scope of the project included in-situ ore body characterization, drill and blast improvements, run-of-mine (ROM) fragmentation measurement and modelling, and crushing and milling optimization. Pustynnoye Gold Mine’s crushing circuit includes a jaw crusher and two secondary cone crushers operating in closed-circuit with classification screens. The grinding circuit consists of a semi-autogenous (SAG) mill with a pebble crusher followed by two ball mills. The SAG mill is unusual, with a low aspect ratio similar to the ball mills. The ball mills currently produce a final grind size of P80 of 75 microns (μm).
Pustynnoye Gold Mine plans to increase the throughput from 2.1 to 2.5 Mt/a and possibly more in future expansions. In order to deliver this capacity increase, management initiated a drill-to-mill project in July 2018.
EMC’S drill-to-mill methodology has delivered significant benefits to the mine: increased fines from blasts (approximately 11% more -10 mm fines; reduced ROM F80 from ~500 mm to ~150 mm; increased dig rates (about 25% to 30%); improved wall control; reduced ore loss/dilution; and increased crusher throughput (16.2%); increased mill throughput (11.6%). This paper explains the methodology followed and presents the results.
Keywords
Drill-to-mill plant optimization, mill throughput, drill and blast, fragmentation, ore characterization, dig rate, crusher, SAG mill, ball mill