Optimising IsaMill operation in copper/gold comminution

The Coalition for Eco-Efficient Comminution (CEEC) has just published the abstract of the paper, Operating performance of the Phu Kham IsaMill, with permission from The AusIMM. The paper is by G. Harbort and D. Zoetbrood.

The Phu Kham copper-gold operation in Laos is owned and operated by Phu Bia Mining Ltd in which PanAust Ltd holds a 90% interest, with the remaining 10% held by the Laos PDR Government. The original 12 Mt/y copper-gold concentrator at Phu Kham commenced production in April 2008. An incremental improvement program resulted in a number of circuit changes being incorporated by 2011, including conversion of conditioning tanks to flotation cells and the installation of a Jameson Cell cleaner scalper. In 2012 an upgrade project was commissioned to increase throughput to 18 Mt/y. In April, 2013 the Phu Kham Increase Recovery Project was commissioned to maximise performance by debottlenecking the plant IsaMillTM regrind and cleaning capacity.

With the variable mineralogy of Phu Kham ore, control of the c concentrate regrind circuit is essential in terms of achieving effective liberation to maintain concentrator performance. On a routine basis laboratory regrind signature plot data is compare with daily surveys of operational IsaMills. More extensive surveys are also conducted to determine size distribution on a mineralogical basis and the effect of fine regrinding on pulp electrochemistry and flotation performance.

This paper provides a review of the operating performance of the Phu Kham IsaMill with regard to power draw, feed and product size distribution, feed per cent solids, mineralogy and pulp electrochemistry. Operating performance is compared with the IsaMill signature plot test for predicting performance.

Last week, Joe Pease and Bill Johnson were inducted into the International Mining Technology Hall of Fame (shown) for the IsaMill.