Many factors affect the implementation of ventilation and cooling in the mining industry, which makes accurate planning dif- ficult, says technology and industrial company Johnson Controls operations manager Russell Hattingh.
This could include politics, economics, labour and the geology of the area where the mine is situated. “Based on past experience, the only constants in the mining industry are uncertainty and change. However, this is not to say that the mining company’s planning is haphazard, but rather that it constantly has to adapt its planning to deal with challenges the mine faces on a micro- and macroscopic scale. Equipment sales into the mining sector is therefore irregular.”
He adds that, despite these challenges, Johnson Controls is still active in the mining industry, citing a recent contract with platinum miner Impala Platinum (Implats) to supply a water chiller for the No 17 Shaft Bulk Air Cooler project, in Rustenburg, North West. This formed part of a shaft sinking project for the main, ventilation and refrige- ration vertical shafts, and included the installation of a 43 m bulk air cooler.
Bluhm Burton Engineering (BBE) Projects, which forms part of ventilation and refrigeration consultant BBE, was tasked with providing the complete bulk air cooling systems for Impala No 17 shaft and contracted Johnson Controls for its York YD model chillers to deliver the solution. The company is finalising other aspects of the mine on-site.
The No 17 shaft is the second fourth-generation shaft complex on Implats’ 15-shaft mine. “Full production for the No 17 shaft is expected to be about 225 000 t/m of platinum reef from the Merensky and the upper group two orebodies.
“Further, the No 17 shaft is expected to produce 180 000 oz/y by 2018,” says Implats Rusten- burg operations executive director Shadwick Bessit.
Meanwhile, Hattingh points out that 13 York plants are functioning at Implats’ opera- tions and that the company is currently in talks regarding the installation of three more cooling units at Impala 17 shaft in the coming years.
Implats refrigeration engineer Andre Pieters confirms this, adding that the plants are reliable and that the miner has experienced minimal problems with the equipment. “It makes sense to standardise our operations by using York chillers for this project and others in the future,” he notes.
The next two chillers will also be used for water chilling and the third as a glycol chiller for thermal storage. “This is the production of ice at night for the purpose of load shifting,” Hattingh says.
He explains that, in terms of the three units to be installed, the company has a phased approach planned, but it is yet to be determined when this will happen, as it depends on the platinum price and whether or not the mine meets its production targets, which, in turn, will depend on a stable workforce.
Hattingh adds that the main challenge with regard to the chillers, although not signifi- cant, is transporting them, owing to their size. The chillers had to be disassembled into several parts before they could be transported to and reassembled at the mine.
This challenge has been addressed, as the York chillers are designed to be disassembled – the shells are split and the compressors and motors are all shipped separately, says Hattingh.