Engineering service and equipment supplier Tenova Bateman Tech- nologies’ modular business unit has been awarded a contract by Anglo American group company Kumba Iron Ore for the supply of a 50 t/h modular beneficiation plant for the Sishen mine, in the Northern Cape province.

This comes after Kumba and mining group Exxaro Resources signed a joint venture development agreement in April 2012 to commercialise the ultrahigh dense-medium separation (UHDMS) tech- nology concept developed by Exxaro.

The lump sum turnkey contract was awarded in September 2012 and will be commissioned and handed over by the end of May.

“The plant includes a feed reception, feed preparation and a dense-media section. The plant is equipped with vari- ous process-measurement and control instrumentation to assist in research,” explains the company.

The plant will be used to demonstrate the commercial feasibility of separating iron-ore at operating densities above 4.2g/cm3 using the cyclone-based UHDMS technology.

Should the demonstration runs prove successful, it would enable Kumba the opportunity to improve separation efficien- cies in some particle sizes fractions above that of jigging technology. With the rheology of the ferrosilicon medium being determined by Exxaro, specific application will be demonstrated, including the use of UHDMS technology to process jig discard and low-grade ore.

The ferrosilicon is produced at Exxaro’s FerroAlloy production facility in Pretoria, which boasts a superior gas-atomised product with unique properties that complement the technology.

Should the UHDMS plant design demonstrate the commercial ability to operate at the projected high-cut densities, it is expected to achieve significatly higher yields at the same product grades, owing to superior separation effi- ciencies that are achievable, compared with the yields when jigging technology is used. The possibility of processing lower-grade iron-ore will also be an option. This is in line with Kumba’s plans for future expansion and optimisation of production through projects dealing with low-grade projects at Kumba Iron Ore.

Operating at high densities and processing ore that had a high percentage of near- density material were not possible until Exxaro successfully proved this at 30 t/h pilot plant. An Exxaro team has been developing and piloting this technology over many years and believes that the technology is superior to current beneficiation technologies in processing these types of ore.

Many dense-medium separation plants have been successfully designed using washability data, but the data was restricted to lower-density applications. Exxaro has also developed the capability to characterise ore at high-densities up to specific gravities of 4.7. This could not be done previously, but the quantification of the potential and the value of the UHDMS technology is now possible. The demonstration plant will assist Kumba Iron Ore in unlocking the value of this material.

The plant will be designed to accommodate the processing of higher-density material and will include pumps that are designed to pump the ferrosilicon medium at the required density and volume

Currently, 90% of the plant has been fabricated off site and the other 10% has already been erected on site, the com- pany tells Mining Weekly.