Modern Quarrying Q4 2018

A 20-t Doosan 225 LCV excavator is deployed to strip overburden and load a Bell B20C articulated hauler.

close to the plant. This allows for up to five days of production without hauling from the pit, in case there are any mining stoppages in the pit. From the ISP material goes to a triple- deck screen. Here the oversize stone is sent to the secondary crusher, a Metso GP220 cone crusher connected with a close loop conveyor setup with the triple-deck screen. All the -8mm sand is removed out of the circuit and sold as scalping sand, mainly used for brick making. The +8mm to -32mm stone is sent to the tertiary stage of crushing, which is a Techroq T12R VSI crusher, to be shaped. Shaping the stone generates a lot of crusher sand, but unlike the scalping sand, the sand is well-shaped and intended for the high-end market. Downstream from the tertiary crusher the aggregate passes over a series of screens, separating the different fractions and stockpiling them. Product range The concrete stone sizes produced are 19 mm, 13,2 mm, 9,5mm and 6,7mm, all being washed before being dropped on stockpiles. Finally, the -5mm crusher sand is also stockpiled. The future plan is to start washing the -5mm sand in order to begin replacing natural sand, which is fast becoming a scarce com- modity in the area. Concrete products are the biggest market drivers for Roodepoort with some strategic customers, such as Coreslab, PPC 3Q Readymix, Technicrete and

An uncompromising focus on product quality has been a key driver of Roodepoort’s early success.

Much Asphalt, located within a kilometre of the operation. Polokwane is a big hub for concrete products, largely driven by the demand from property developers and the demand for prefabricated products over the entire Limpopo province. In spite of the tough economic spell in South Africa, the property market in Polokwane remains very active, having topped the R1,1 billion mark in 2017. To maximise profitability, all material from the pit is processed, with no form of waste on site. Overburden material is separately crushed using a Komatsu BR380 mobile jaw crusher, producing G-type material used as base and sub-base material in road construction. At the time we visited the site, the static plant was producing about 22 000 tonnes per month, while the mobile plant added another 3 000 tonnes. Four front-end loaders are working on site. A Liebherr L550 front-end loader is deployed to feed the mobile jaw, while the two Komatsu WA250 units are used for stockpiling and loading of customer trucks. A Volvo L150G is deployed for material stockpiling at the ISP. l

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QUARTER 4 - 2018 MODERN QUARRYING