The Weir Group has announced a new alliance with Swiss Tower Mills Minerals (STM) in which Weir will market STM’s vertical stirred grinding mills for coarse grinding applications worldwide.

Integrating vertical stirred grinding mills into Weir’s minerals processing flowsheet will provide customers substantial improvements in throughput and energy efficiency, helping them to meet their productivity and sustainability goals, Weir says.

STM’s vertical stirred grinding technology is proven for energy efficient comminution in the mining market with more than 80 units currently operating in the hard-rock mineral processing industry across the globe, according to the company. It is used within the comminution segment of the minerals processing circuit as part of a series of crushing and grinding processes that create the fine particles from which minerals can be extracted through flotation.

Comminution, as has been well documented, is one of the most energy intensive parts of the mine, accounting for 25% of the final energy consumption of an average mine site.

Weir says it is already a leader in comminution technologies, offering solutions such as Enduron® high pressure grinding rolls (HPGRs) to drive down energy consumption by around 40% for customers.

This new alliance with STM takes things to the next level, offering the mining and minerals industry a proven low energy alternative to traditional high energy consuming tumbling mills, it said. Combining and integrating these energy-efficient technologies into a single, optimised flowsheet will deliver significant reductions in energy use, driving down costs and carbon emissions.

In order to prove the most beneficial flowsheet for specific projects, STM has already supplied two vertical test mills to the Weir Minerals HPGR test facility in Venlo (Netherlands). This will put Weir and STM in the unique position to provide clients combined energy efficient grinding test work of HPGR followed by STM’s vertical stirred mill, they said.

Ricardo Garib, Weir Minerals Divisional President, said: “Weir and STM share the same vision of enabling primary resource providers to produce resources in the most sustainable manner. This is a perfect match of best-in-class technology providers. Integrating STM mills with Weir’s comminution products, which includes Enduron HPGRs and Enduron screens, will improve throughput and help bring substantial reductions in carbon emissions.

“This is a real win-win.”

Fritz Moser, STM Chairman, said “Both the HPGR and the STM vertical stirred mills provide significant energy savings compared to conventional grinding technologies. Our new supply agreement with Weir will enable us to fast track the roll out of an innovative flowsheet using STM mills in conjunction with Weir’s Enduron HPGR.”