Weba Chute Systems has successfully engineered a new transfer point to replace an underperforming chute at Carmen de Andacollo in the Coquimbo region of Central Chile.

Carmen de Andacollo is an open pit copper operation; Teck owns a 90% interest in the mine with Empresa Nacional de Mineria holding the balance of shares.

The new chute system transfers material from a double deck screen feeding oversize material from both decks to a conveyor. Material throughput is 2 000 tph with a lump size of minus 85 mm.

Alwin Nienaber, technical director at Weba Chute Systems, explains that in the previous installation the manner in which material was being presented onto the conveyor was causing impact damage and excessive spillage. The spillage had to be controlled using extremely hard skirtings under such tension that this had been causing extreme damage to the conveyor resulting in frequent belt replacement.

“It is not uncommon for us to see this type of issue which arises from inadequate plant design,” Nienaber says. “When the transfer points do not receive the requisite attention during the design of the plant, numerous problems can occur during operation.”

As a transfer point specialist, Weba Chute Systems is a strong advocate of their involvement at the start of a project. “This approach ensures that the transfer points are engineered for the particular plant, with the advantage that material transfer will be optimised and wear and impact issues such as those found at Carmen de Andacollo could be mitigated from the beginning.”

Where operational plants experience issues with transfer points, Weba Chute Systems sends in its technical team to conduct a full design assessment.

According to Nienaber this is a critical step in the process as it will ensure that the solution provided takes all factors into account. He explains that the previous chute was essentially just a box structure and this was problematic as the material flow was not controlled and it directly impacted onto the conveyor from the screen. To add to this situation the receiving conveyor design was also compromised.

“We were able to design a new transfer point solution that would accommodate the shallow flow angle required in this application,” he says. “By custom engineering the chute we were also able to design it in such a way so as to feed the material onto the conveyor in the direction of belt travel. This then eliminated the issues associated with the previous direct impact.”

The design of Weba Chute Systems also allows for absolute control of the material and, in this application, has been configured to force a concentrated stream from the screen decks onto the conveyor. Due to the compromised general arrangement between the screen and conveyor, skirts are still required to eliminate spillage.

To provide further protection against sliding abrasion, the chute has been lined with high alumina ceramic tiles.

The Weba Chute Systems installation at Carmen de Andacollo was commissioned in the first quarter of 2017. Nienaber says that much of the work has been done through Weba South America which was established in Chile to service this region.

Under the leadership of Pedro Javier Vega, Weba South America has been making inroads into the mining and minerals processing sector. “The local team has a good understanding of the industry, its immediate and long terms needs, and will provide consistent support to this customer,” Nienaber says.