Client: Minera Yanacocha S.R.L. (Newmont Mining, Minas Buenaventura S.A.A.)
Location: La Quinua Mine, Cajamarca, Peru
Project Classification: Detailed Engineering, Thickened tailings disposal system
To treat high grade ore Yanacocha implemented a milling process at the La Quinua operation. However, limited sites were available for the tailings storage facility. To best utilise the available area the tailings storage facility is fully contained within an active heap leach pad. Consequently high concentration thickened tailings are required to reduce the amount of water placed in the facility. The tailings are thickened at the mill in a high rate thickener before being pumped to the storage facility by a train of centrifugal slurry pumps.
The design considered the following key issues:
- The optimum design concentration to increase the tailings concentration, while maintaining reasonable capital costs for the system
- Pipeline material selection to achieve the required pipeline life
- The risk of particle settling in laminar flow
- Pipeline emergency flushing and shut down measures.
Paterson & Cooke provided laboratory test work, trade-off studies, detailed engineering and start-up commissioning assistance and have since completed the design of the phase II pipeline expansion project.
Kerr, TF, PD Duryea, W Grobbelaar and K Hackney (2007) “Design of a Thickened Mill Sands Management System within a Leach Pad”, Paste 07, ACG, Perth.
Keevy, M and K Hackney (2007) “Pump Station Drive Selection Case Study”, Hydrotransport 17, SAIMM/BHR, Cape Town.
Key project data
Gold tailings Capacity: 620 to 740 t/h
Pipe diameter: 300 mm
Length: 4 km
Pump station: Centrifugal
Max pressure: 3 000 kPa
Concentration: 65 to 71%m
Yield stress: 8.5 Pa