Mining Mirror May 2018 - Page 37

Cradle to grave Tyres in a time of scarcity The Department of Mineral Resources (DMR) lists 881 quarrying operations located throughout South Africa. In 2016, 92.2 million tonnes of mined aggregate, clay, natural sand, dimension stone, and limestone to the value of R9.4-billion were sold locally, while the value of exports of quarry products reached USD61.5- million. (https://www.prnewswire. com/news-releases/stone-quarrying- clay-and-sandpits-in-south- africa-2017-300539976.html) Every day, dozens of short haul dump trucks amble from the breaking and loading site to the first crushing site, carrying those millions of tonnes of payload — the rock that will eventually become the paths, roads, and bridges we all traverse. If the average resident does not realise the intense, lengthy process that aggregates like limestone, for example, go through to become the familiar cement sidewalks, even more so, they would not realise the vital role that mining tyres play along the way. In quarrying, the tyres on all the equipment are key to ensure that the product gets mined and transported to the crushers until the finished product is ready for industry. Tyres used in quarries are placed under severe stress, and it is important that they always perform optimally. Eight years after Kal Tire was established in South Africa, and having acquired Tyre Corporation in 2017, the company now has more than 1 100 team members providing mining tyre maintenance and supply across 80 South African mine sites. Considering training standards, a scarcity of tyres, and customers’ need for value, Kal Tire is demonstrating how advanced training and tyre maintenance go a long way to meeting customer expectations. In a bid to reduce injuries and fatalities, South Africa’s mining bodies have developed policies that insist workers are sufficiently trained and certified before even entering a mine site. For Kal Tire, an international company with more than 6 500 team members serving mine sites across five continents, consistency and high training standards are key. As the Kal Tire Mining Tire Group began orientation with Tyre Corporation team members, the company rolled out waves of training that reached even the most remote corners of South Africa to ensure everyone was trained to both the country and Kal Tire’s standards. It was also an excellent opportunity for Kal Tire to introduce new team members to the company’s AIMS: seven guiding principles that define who Kal Tire is, and to instil the Kal Tire values, describing everything from safety and quality to relationships and integrity. (usually less than a minute), which results in a long lifetime for the adsorbent material. Recent advances in adsorption technology and system design by Linde Engineering have enabled oxygen VPSA plants to become less expensive, more power-efficient, and smaller in size. The result is that an oxygen VPSA system offers a very cost-competitive, flexible oxygen supply solution that has demonstrated excellent results in a variety of commercial applications in the mining, chemical, and refining industries on a global basis. For low-purity (<95%) applications with flow rates from 10 to 342 tonnes per day, which are the typical requirements for gold mining applications, VPSA has proven to be the most cost-effective solution. The VPSA plants have a very low specific energy consumption and operate at low pressure, with booster compressor to achieve customer pressure demands. They offer an extremely competitive capital and operating cost per tonne of oxygen produced. VPSA plants provide oxygen on demand with easy turndown from 0 to 100%, have high availability, are fully automatic, and can be remote controlled and monitored. Furthermore, VPSA plants are standardised with a modular construction, enabling reduced field construction and commissioning time. As part of the Goldox PSO, Afrox can also offer a downstream oxygen management service where Afrox operates and maintains the oxygen injection equipment to achieve the desired dissolved oxygen (DO) levels in the leach as required, thereby freeing up the plant metallurgists to concentrate on managing the gold plant. “The supply of oxygen to the gold leach needs to be supplemented by an efficient injection system to ensure optimum oxygen utilisation in the slurry, otherwise the benefit of the oxygen injection may be limited,” explains De Zoeten. MAY 2018 MINING MIRROR [35]