The Sepon Copper project is a patented copper leaching process comprised of crushing, acid grinding, acid flotation, pressure oxidation and a solvent extraction electrowinning circuit designed to produce 60 000 t/y of cathode copper, which has subsequently been increased by Ausenco to 80 000 t/y.
The project scope included all plant services including reagents, oxygen plant, cooling towers and infrastructure such as power supply, water supply, accommodation to house 4 000 personnel, roads, bridges, waste services and tailings storage.
Ausenco’s scope was for the full EPCM of the project which included process plant and associated infrastructure.
- EPCM US$235m for a 60 000 t/y SXEW plant and US$31m for the gold plant expansion
- First acid milling hard rock grinding circuit in the World – use of large ceramic balls and stainless throughout – technical challenge
- 35,000m3 of concrete in the copper and gold plants
- 3 500 t of structural steel mostly sourced from Thailand
- 70 km of complex piping and 260 km of cabling
- 3 000 construction personnel on site from a cultural background of over six countries
- Completed 2 weeks ahead of a schedule and under budget
- Significant procurement and logistical challenges
- 6 714 046 man-hours at 0.6 LTIFR, peak 3 400 personnel
- Innovative and complex copper leaching process
- Winner of 2005 National Engineering Excellence Award.