Compañía Minera Doña Inés de Collahuasi is the fourth largest copper producer in Chile and currently ranks sixth in global copper reserves. The mine is located in northern Chile, about 180 km southeast of the port of Iquique, at an altitude of 4,000 meters. In addition to copper concentrate, Doña Inés de Collahuasi produces cathode copper and molybdenum concentrate.
The mine’s long history dates back to 1880. And there is no end in sight to its success. In 2013, production reached 444,509 metric tons of fine copper. This represented a 58% year-on-year increase, the largest increase among Chilean miners.
But just like miners all over the world, Doña Inés de Collahuasi is faced with the perpetual challenge of running its operations as efficiently as possible. To ensure future productivity and profitability, Doña Inés de Collahuasi decided to embark on a preventive improvement program. The objective was to detect potential problems in advance and to maximize the performance and availability of the existing equipment.
Integrated solution ensures success
As part of the improvement efforts, the mining company contacted Metso for the manufacturing and mounting of a new chute with four outputs for a 10’ x 11’ SAG mill. Pleased with the good results and the fact that all deadlines were met without any accidents, Doña Inés de Collahuasi soon decided to order three more chutes from Metso for the pebble stage.
Metso’s unique ability to offer an integrated solution was one of the key factors in the company’s decision to collaborate with Metso.
“As a company we look for suppliers who can provide an integrated service that includes engineering, manufacturing as well as assembly,” Manuel Vera, Asset Management and Reliability Manager at Minera Doña Inés de Collahuasi, explains.
Difficult maintenance and excessive wear a challenge
Metso’s integrated approach consisted of several phases, starting with the gathering of field data about the existing chutes in operation.
It turned out that the structures needed improvement and that a liner change-out was quite difficult. In addition, the chutes were unable to absorb the full impact of the falling mineral. All this added up to an insufficient flow, as evidenced by the large amounts of ore in the passageways and around the transfer chute. This excess material created premature wear in the conveyor belt and its support structure.
These findings were passed on to the design, where they resulted in proposed improvements that were then validated through HFS simulations. The design improvements will reduce downtime for liner change-outs and thus increase availability because less time will be needed for scheduled maintenance. Additionally, the new design included chute door systems for inspection and maintenance.
Metso’s integrated solution also included carrying out the actual liner change-out and the assembly of the new chutes, as well as a follow-up on the performance of the liners and a continuous improvement plan for the transfer chutes.
Extended wear life with Trellex Poly-Cer
Trellex Poly-Cer from Metso is a modular system made of ceramics and rubber, which makes them resistant to strong abrasion – even with a high tonnage and at high speeds. The new design of the chute liners makes maintenance easier by streamlining the change-out of the anti-wear plates within each structure.
Trellex Poly-Cer is designed to increase liner wear life. Thanks to its greater resistance, it is typically up to ten times more wear-resistant than its steel counterpart. Trellex Poly-Cer consists of ceramics (1400 HB) and rubber, offering both wear resistance and elasticity to absorb impacts.
Impressive results
As a result of the new design, the service life of the chutes at Doña Inés de Collahuasi has increased.
“The original design required maintenance every 20 days or so, but now the interval is longer, and we know that optimization of this can continue,” Manuel Vera says.