Quarry Southern Africa May 2017 - Page 21

Winning Wirtgen SA’s final demonstration of the 2200SM took place at an open cast coal mine in Delmas with the primary objective to improve the yield at the production plant. waste material, so conventional mining is not an option – drilling and blasting would make the material unusable due to high contamination. Basically, the only reason the FMG mine exists is because of our machines and the way we operate. Currently, Wirtgen has supplied 27 of our big machines (4200SM) and 14 of our middle-size machines (2500SM) to FMG.” “We’ve also got a lot of machines working in Guinea, on bauxite. What makes our machines so effective there is the high rainfall,” Newby continues. “It rains for roughly 80% of the year in Guinea, which is a big problem for drilling and blasting operations. With our machines you can carry on working, because the cuts not only create a very smooth surface, but also one that is very stable, with minimal cracks, which means minimal water penetration into the ground. This means that the cutting and loading onto the truck is all dry, and the trucks themselves aren’t creating this big muddy mess.” In addition to coal, iron ore and bauxite, the 500 machines Wirtgen has operating around the world are also working in limestone, gypsum, salt, phosphate, oil sands, kimberlite, mudstone and even granite. The ZAO Kavkazcement limestone mine, located near the Black Sea in Russia, is a member of the Eurocement Group, one of the top five largest cement companies in the world. Since 2005, the mine has used Wirtgen Surface Miners for its surface operations – first two of the small 2200s, and then, following their success, and additional three 2500s. Eurocement’s decision to use the surface miners was based on three criteria: that they should deliver the required tonnage with high productivity and at low operating costs; that the material should be reliably crushed within the prescribed gradation; and that the miners should suit the existing mine structures optimally. Eurocement mining director Victor Gustov highlights the benefits of using the surface miner in their operations, “The use of surface miners takes a huge strain off the environment during limestone mining in the regions affected – while increasing safety in the mine at the same time.” One of the main advantages of surface mining over drilling and blasting is that the limestone can be loaded directly onto trucks. However, the cutting process is always entirely independent from the truck loading, and if material is required for a temporary embankment stabilisation, for example, the surface miners can discharge the cut limestone sideways onto a pile. The way forward The Wirtgen Surface Miner is particularly well suited to mines that have sections of ore that can’t be mined because of its proximity to oil pipeline, houses and highways. Because of how it operates there are no vibrations and no flying rocks – it is extremely safe and allows more of the ore to be exploited. Despite the obvious advantages, it’s going to require a complete mindset change for South African mines and contractors to take up the technology, although the successful demonstrations seem to have started this change. Specifications There are four models of Surface Miner: • The 2200SM (with a cutting width of 2.2m and a depth of up to 30cm); • The 2200/3.8SM (with a cutting width of 3.8m and a depth of 30cm); • The 2500SM (with a cutting width of 2.5m and a depth up to 65cm); and • The 4200SM (with a cutting width of 4.2m wide and a depth up to 83cm). QUARRY SA | MAY 2017 _ 19