Modern Mining July 2018

IRON ORE

between 2014 and 2017 and had involved an investment of R749 million. McGavigan said technology projects com- pleted during this period at Sishen – and its sister mine Kolomela, near Postmasburg in the Northern Cape – had included an upgrade of the fleet management system to optimise load and haul cycles to maximise productivity and efficiencies. This had resulted in the average queuing time for the 960E haul trucks being reduced from 5,7 minutes in August 2015 to 4,9 minutes in September 2017 and the aver- age speed of the trucks increasing from 21,2 to 29 km/h. The project, he said, had included the installation of a high-precision GPS shovel guidance system. Automated or autonomous drilling – in which drill rigs are controlled from a ‘Drilling Command Centre’ – had also been intro- duced, McGavigan told the media group, with Kolomela being the first to move over to the new technology with Sishen now following with two of its Atlas Copco Pit Viper blasthole rigs having already been converted. Kumba is the first iron ore miner in Africa to switch over to autonomous drilling and one of the pioneers worldwide, with only BHP Billiton in Australia using similar technology. Based on Kolomela’s experience, the benefits of autonomous drilling are considerable. They include improved safety and drill hole quality and increased direct operating hours (from 17,3 to 18,6 hours per day on average). The levelling time for each drill has been reduced from 1,3 minutes to 0,4 minutes and tramming time has improved from 2,4 minutes to 0,9 minutes. Other successful technological initiatives at Sishen and Kolomela since 2014 have included the upgrading of information systems, the use of a geo-spatial data capturing tool, the intro- duction of Mine Information Systems and the installation of Advanced Process Control (APC). The APC technology, which allows improved measurements and control of the processing plants through automation, has already been rolled out at Kolomela and is now being applied at Sishen. The benefits already delivered by APC at Kolomela are impressive, with an 83 % improvement in plant stability, a 6,5 % increase in plant throughput and a 1 % improvement in the lump to fine ratio having been achieved. Drones support much of the technology, par- ticularly the Mine Information Systems, which enable the concept of the ‘connected mine’ to be realised by providing central data warehous- ing, reporting and analytics tools to integrate all the data generated at Sishen and Kolomela.

saleable production by up to 2 Mt/a. One of the resources that could be exploited is the stock- piles of marginal material that have been built up at Sishen over the years. Kumba is currently busy with a Bankable Feasibility Study (BFS) on an upgrade of the current DMS plant to UHDMS technology to allow it to process both high and low grade ore simultaneously, which would involve the DMS components of the plant being converted to UHDMS processes and the installation of an additional primary crusher. The study is due for completion in the second half of next year. Should it be positive, it is envisaged that con- struction of the upgrade could start in 2020 with full production being achieved in 2023. While Mobwano gave an overview of operations at Sishen and of the impact of new methodologies and technologies, Glen McGavigan, Kumba’s Executive Head of Technology & Projects, spelled out Kumba’s technology roadmap in some detail to the media group. He said Kumba had started its technology journey in 2014, with its immediate focus being on what Kumba terms ‘Horizon 1’ – essentially the introduction of new but largely proven and immediately available technologies. These, he explained, had been implemented

A blasthole rig at Sishen. The mine is in the process of converting to autonomous drilling.

32  MODERN MINING  July 2018