Traditionally the preferred choice for cement grinding and diamond applications, HPGR technology has in recent decades proved its mettle in hard rock applications such as copper, gold and platinum processing. However, its strong presence in hematite and magnetite greenfield and brownfield projects has firmly established Enduron HPGR as part of the ‘blueprint’ flow sheet for sustainable iron ore processing.
“We have seen a massive uptake of our Enduron HPGR range in iron ore, where we have the largest installed base,” says Nathi Mtsweni, Senior Process Engineer for Trio/Enduron Comminution products at Weir Minerals Africa.
Two flagship projects
Testimony to the growing appetite for HPGR technology in iron ore applications are two key flagship installations underway in Australia and Nigeria, West Africa. To process 90 000 tonnes of ore per day, the Nigerian project represents Africa’s biggest HPGR plant in an iron ore application to date.
In 2019, Weir Minerals received a £100 million order for 12 Enduron HPGR machines and Geho Positive Displacement pumps for a magnetite iron ore application in Australia. Installation is underway, and once complete, this will be the world’s biggest HPGR installation in an iron ore application.
Equal to the task
Due to its abrasiveness and density, iron ore is tough to process, but HPGR technology is equal to the task. Thanks to its unique bearing arrangement which enables durable skew – designed to guard against premature failure and reduce the number of peak loads transferrable to the bearings – the technology delivers a long bearing life of well above 10 years in these rogue applications.
“With our unique bearing assembly that reduces the risk of failure, coupled with the wear reduction capabilities associated with skewing, our machines are expertly engineered to last longer while performing effectively regardless of the feeding conditions,” Nathi adds.
The longevity of roll life is critical to the overall performance of the processing plant, both in terms of availability and operating costs. Weir Minerals has paid particular attention to the surface of the rolls, which incorporates tailored tungsten carbide studs to ensure strong autogenous wear protection. As a result, the Enduron HPGR technology offers up to 20% more roll life than the competition.
Only one roll set change
On one of the installations in South Africa, a customer processing fluorspar ore is enjoying more than the anticipated 10 000 hours of roll life. In fact, since commissioning in 2018, the first and only roll set change was undertaken in July 2021.
“With its ability to reduce grinding energy by as much as 40% without the need for process water and extending its low impact benefits when combined with dry air classification, Enduron HPGR technology revolutionises traditional iron ore processing towards an effective and sustainable fine grinding solution ,” Nathi concludes.