Modern Quarrying Q1 2020

With new neighbours, some of them only 250 m away, management at AfriSam’s Jukskei quarry has carefully managed the transition and the environmental aspects that come with the new setting.

KEY TAKEAWAYS

that from an economic point of view, the innovative static water spraying system translates into less diesel burn as it eliminates the need of a water tank moving up and down the haul roads. Crushing rock is a high dust activity that in the absence of controls would place workers and the close-by communities at risk. Another key intervention in this regard was the installation of de-dusting sprays in the vertical shaft impactor (VSI) crusher. The system minimises dust generated during the crusher’s start-up process. Water is delivered as a fog, mist or fine spray to the crusher chamber during start-up, where it combines with airborne particles created by the VSI, enlarging the particles and causing them to settle. “A VSI generally generates excessive dust during start-up when it’s still empty. The spraying system, installed in the chamber itself, is active during the first few minutes of start-up, thus mitigating excessive dust emission,” explains Du Preez. Meanwhile, the monthly dust samples – performed by a third party service provider – measure fall out to ensure that the quarry doesn’t exceed prescribed limits. Seven sample points have

While rapid urbanisation in the vicinity has changed the fortunes of Jukskei quarry, AfriSam has had to deal with new environmental aspects, which have been addressed through an array of initiatives

To mitigate excessive dust emission, a water spraying system has been installed along the main haul roads

De-dusting sprays have been installed in the vertical shaft impactor to minimise dust generated during the crusher’s start-up

Monthly dust samples – performed by a third party service provider – measure fall out to ensure that the quarry doesn’t exceed prescribed limits

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QUARTER 1 - 2020 MODERN QUARRYING