During the first half of 2009, commissioning of the Pilanesberg Platinum Concentrators progressed well with the completion of the cold commissioning of the UG2 section.
This milestone was achieved 4 March 2009, one month ahead of schedule. The UG2 plant ramp up was completed and handed over to Boynton Investments. Merensky hot commissioning on the secondary mill circuit began on 11 May 2009. The Merensky primary mill circuit is scheduled for completion in early June despite the late delivery of the primary mill girth gear. Three million LTIF hours were reached from inception to April 2009, with site personnel peaking at 1,950 at the beginning of the year.
DRA was responsible for the process, civil, structural, mechanical, electrical and instrumentation design, construction and commissioning of the entire concentrator complex from the ROM receiving bins through to the tailings dam.
The plant treats two types of ore: UG2 at 65 000 tpm gets processed in the UG2 concentrator section; the Merensky (300 000 tpm), which itself consists of two types, contact reef and pothole reef, goes to the Merensky concentrator section.
The UG2, after coarse crushing, goes to a two-stage mill / float circuit, followed by concentrate thickening, filtration and dispatch. The Merensky contact is crushed to -16mm, fed to a DMS plant to remove waste, and re-crushed. The pothole reef also undergoes two-stage crushing but bypasses the DMS.
The Merensky crusher products are combined for two-stage milling / flotation and filtration. The UG2 and Merensky concentrates are dispatched separately. The tailings are pumped to a combined tailings dam.
DRA’s project manager, Willem Postma, says: “Considering the rapid changing market conditions, the size of the project and the lateness of some of the mill components, the Pilanesberg Platinum team did very well and DRA can be proud of them.”