Weir Minerals Africa installed a Trio EF3606 pan feeder at OMV’s Stilfontein crushing plant, increasing production by 40% and helping create a safer working environment. Their target was 1 300 tonnes per day, but the plant could only produce 1 000 tonnes per day. As Weir Minerals Africa has been working successfully with OMV for more than five years, OMV requested their help in increasing the plant’s capacity.
The lack of plant capacity was deemed to be a result of the stockpile reclaim chutes regularly becoming blocked, resulting in an inconsistent feed to the cone crushers. As the cone crushers were unable to be choke fed, OMV often experienced an inconsistent product, crusher inefficiencies and uneven wear of their cone crusher liners.
To address this issue, OMV had to constantly monitor and manually clear the feed from the chutes. Manually clearing the feed presented a considerable safety risk, as rocks would fall out of the chute once the blockage was removed.
To provide a reliable and consistent feed to the cone crushers, a Trio EF3606 vibrating pan feeder was selected. This series is perfectly designed to perform in surge tunnels or under surge bins, controlling the feed rate to the next stage of processing. Combining the pan feeder with a variable speed drive (VSD) and a programmable logic controller (PLC) allows the feeder to alter its speed, based upon the levels of feed already within the cone crusher’s bins.
Weir Minerals Africa’s engineers also redesigned the chute system, and used 3D laser scanning equipment to ensure the new structure and chutes would fit within the existing footprint. The team used simulation software to reproduce and optimise the particle flow through the new chute design.
After commissioning, OMV’s capacity was immediately increased to 1 400 tonnes per day, a 40% daily production improvement that resulted directly from the consistent feed to the cone crusher. Furthermore, no blockages have been experienced since the new feeder has been installed. The plant has increased its uptime to as much as 99.5% of its 10-hour shifts, and the safety risk of clearing the chute has been removed.