Modern Mining October 2018

DIAMONDS

will definitely pay off,” says Häggkvist. Imilingo is now working on an enhance- ment of the iDredge™ for an Angolan company, MONTHE REAL LDA. “They came to us with a concept where they wanted a sorting system – which will comprise two TOMRA X-Ray Transmission (XRT) units – on the dredge,” says Prinsloo. “This makes the entire assembly much larger than the current iDredge™.” The iDredgeXRT™, as the new unit is known, will include – apart from the sorters – a submersible pump with excavators, a clam- shell, a sizing screen and two diesel-electric generators to power the system. It will also be equipped with three-dimensional sonar for viewing the pumping operations and a global positioning system (GPS) to track the locations where mining has been done. “The fact that only one processing step is required when utilising the XRT technology makes this solution a huge win in terms of process efficiency. In other words, the mate- rial is mined and then processed through the XRT machine (one processing step) to achieve a hand sortable product. The material quantity is small enough that no other mechanised step is required,” comments Prinsloo. He adds that TOMRA is a world leader in XRT technology with its machines having had huge success in a number of diamond-mining projects, including the Karowe diamond mine of Lucara Diamonds in Botswana. The iDredgeXRT™ is currently at the detailed design stage. Fabrication is expected to start early in 2019. Prinsloo notes that the prospective site for the new machine has water depths (due to a

dam downstream) of up to 80 m, with the dia- mond-bearing gravels only starting at a depth of around 45 m. “We are therefore designing the new dredge so that it can work down to 80 m,” he says. “Conventional alluvial diamond min- ing methods which rely on divers equipped with suction hoses going down to the river bed would certainly not be a feasible approach at this site.” Founded four years ago, Imilingo – as we reported in our article last year – describes itself as an “engineering company with a vision to be the leading integrator of sensor-based sorting technologies.” In essence, it offers the mining industry fit-for-purpose complete sorting sys- tems, based on pace-setting technologies such as XRT. Its modular products include iPlant™, iFeed™, iConvey™ and iScreen™, with the iDredge™ and the iDredgeXRT™ being the lat- est additions to its line-up. 

The iDredge™ was tested and demonstrated at a dam near Balmoral in Mpumalanga last year.

October 2018  MODERN MINING  25