Cu–Ni processing improvements at First Quantum’s Kevitsa mine

• An overview of the Kevitsa processing operation and its challenges is outlined.
• Processing improvements to meet processing challenges are described.
• The plant results of these changes are documented in the paper.
• Reconfiguring the circuit improved plant copper upgrade and flotation selectivity.
• Installing 2 column cells and magnetic conditioning also increased metal recovery.

First Quantum’s Kevitsa Mine is located in northern Finland and mines a large, low grade, polymetallic ore body. The processing rate is currently 6.7 million tonnes per annum (mtpa) up from the design rate of 5.5 mtpa. Payable metals include nickel, copper, gold and PGM group metals. Profitability, at high volume, low grade operations like Kevitsa, is highly geared to metal prices and process improvements. Unusually, for a high tonnage low grade operation, metal losses at Kevitsa are primarily in the finer fractions.Since the operation commenced there has been a focus on maximising the separation process so as to improve the Cu–Ni process profitability. This has included:1.Optimising the flowsheet2.Installing column cells3.Improving fines recoveryThis paper will outline these process improvements, their introduction and efficacy.