The Hera Project processes ore from the Hera Mine to produce gold-silver doré bars and a ‘bulk’ (lead+zinc) concentrate for sale.
The process flow sheet in summary, consists of:
- Primary, secondary and tertiary crushing circuit to produce a P100 of 2.36mm
- A gravity gold circuit consisting on an Inline Pressure Jig (IPJ), 2 x inline spinners and a Falcon centrifugal concentrator. These devices produce a gravity concentrate that is leached with Inline Leach Reactor (ILR) producing a gold solution to the electrowinning cells to deliver gravity gold doré for sale
- A VTM-400 vertimill to produce a sub 250 micron feed to the flotation circuit
- A rougher and cleaner flotation circuit to produce a lead-zinc concentrate grading +50% lead + zinc
- A gold leach circuit which leaches the cleaner concentrate to produce a gold-silver bearing leach liquor and a final concentrate for sale
- The gold-silver bearing leach liquor is presented to a Merrill Crowe circuit to produce gold –silver doré for sale
The Hera Process Plant is designed to process 350,000 tonnes per year based on 50 tonnes per hour at 80% availability.
Following a challenging commissioning, Aurelia has made or is making a number of capital improvements to the process plant to improve metal recoveries and lift process plant throughput, including:
- Gravity circuit upgrade – due June quarter 2016
- Contract primary and secondary crushing – commenced Feb 2016