The long and close cooperation between Cobre Las Cruces (CLC) and Metso has led to a tradition of continuous improvements at the mine. This cooperation has most recently resulted in grinding media consumption being reduced by 10% and the installation of Poly-Met™ mill linings has also lowered costs by 15% due to longer wear life and fewer liner changes.
Grinding media has always been the second-highest operating expense, after energy consumption, for many mining customers. Reducing the consumption of grinding media while simultaneously improving grinding efficiency and reducing energy consumption are common issues in the mining industry.
Working together to find the best solutions
Since production started in 2009, Metso has provided CLC with forged balls (80 mm size) and linings for their 5 x 6.95 m primary ball mill. Over the years, several successful programs have been put in place in order to reduce ball consumption, minimize grinding ball inventory, reduce energy consumption and improve end product.
Mr. Alcón, Mineral Process Manager at CLC, clearly states that all of these challenges are positively impacted by many factors, among which, for sure, is the quality of Metso’s grinding balls. “Since the start of the operations here, we haven’t seen any broken balls and the shape of the balls produced by Metso are close to being perfect,” he says. “These clearly influence the grinding efficiency and energy consumption in a positive way. Over the years, Metso has always partnered with us to find better solutions to these challenges. They bring us the best benefits when comparing grinding media and mill linings from other suppliers. Today our whole plant is running at over 95% availability, which is above international standards and we’re sure that is partly the result of working together with Metso.”
“Cobre Las Cruces is very happy with Metso’s support and collaboration. Having been able to reduce the consumption of grinding media by 10% has easily translated into savings of several hundreds of thousands of euros. Needing to handle fewer balls over time also has an effect on the health and safety of our people. Fewer ball changes needed and no broken ones inside the mill reduces the risk of accidents – and that is also worth mentioning!” Mr. José Luis Bonilla, responsible for external relations at CLC, states.
Longer wear life and fewer mill liner changes
In addition to the grinding media, CLC is also using Metso's Poly-Met™ mill lining, which they are very satisfied with, according to Mr. Rafael Sánchez, Maintenance Supervisor at the CLC plant. “We are able to change the plates and lifter bars inside the whole mill in only 2 days and we only need to do this every 7 to 8 months. This previously was needed every 4 to 5 months. Since we changed to the Poly-Met™ mill lining, our costs decreased by around 15% due to the longer wear life and fewer liner changes.
Ongoing evaluation and improvement
The constant monitoring of operations and looking for improvements is an ongoing project. The material to be processed and the conditions often change, so there is no absolute solution for these topics. Close communication with our partners and a good understanding of our operations is therefore key – and Metso is definitely one of those partners!” Mr. José Luis Bonilla says.