Weir Minerals has helped OceanaGold reduce grinding mill recirculation by 246 per cent with its Cavex hydrocyclones at the Didipio gold-copper mine in the Philippines.
The drop in grinding circuit recirculation has helped OceanaGold save more than $US800,000 ($1.16 million) a year on direct power and ball consumption and cyclone and pump maintenance costs.
Weir installed 19 Cavex 400CVX10 hydrocyclones at the mine, which improve separation efficiency with their finely tuned spigot liner diameter and cast housing. This provides strength and corrosion resistance.
The Cavex hydrocyclones features a 360-degree laminar spiral inlet geometry design, which gives a natural flow path into the hydrocyclone, allowing feed to blend smoothly inside the chamber with rotating slurry, reducing turbulence.
OceanaGold has previous experience using Cavex hydrocyclones across its New Zealand sites, so Didipio processing manager Gary Webb was positive they would be a good fit at Didipio.
“We were confident that retrofitting Cavex hydrocyclone cluster at Didipio with an increased number of smaller cyclones would help reduce our problematic circulating load and lever multiple benefits in doing so,” Webb said.
“The changeover has exceeded our expectations, enabling higher throughput and lower consumable costs without being penalised in grind size.”
The Didipio mine sits on the island of Luzon and produced 114,985 ounces of gold and 14,999 tonnes of copper in 2018.
The mine is governed under the terms of a financial or technical assistance agreement (FTAA), which gives OceanaGold the right and responsibility to explore, develop and operate Didipio, but does not give it ownership of any mineral resources.
Under the FTAA, the Philippine government receives 60 per cent of Didipio’s net revenue while OceanaGold is entitled to 40 per cent.