African Mining November 2019 | Page 64

 CRADLE TO GRAVE SMARTER COAL SAMPLING Weatherby has refi ned the procedure to test coal samples in the TDS, characterising all the components of the sample prior to a full test. “I changed the sample procedure in such a way that we can actually characterise the various elements of the coal seam before we apply the necessary algorithm, thereby giving a much better calibration curve,” says Weatherby. A proprietary testing procedure developed specifi cally for South African coal samples by WMP Consultants for the Telligent Dry Separator (TDS) has been trialled successfully at the DADI Engineering Development Group sister company Meiteng Technology by consultant Tony Weatherby on behalf of Aury Africa. A sample from a discard dump in KwaZulu-Natal has been tested successfully. As a result, Aury Africa is in the process of sending a 20t bulk sample to China for validation of the test initial results, followed by a further six run-of-mine (ROM) samples of discard and coal- recovery samples from various customers. A particularly exciting development has been the successful testing of a sample from a discard dump in KwaZulu-Natal, containing a mixture of bituminous and anthracite coal from two separate mining streams. The TDS was able to clearly diff erentiate the two materials in the sample, which means that discard dumps can be turned into potential sources of additional revenue for mining operations. conveying system that incorporates dual X-ray technology. It can be retrofi tted to an existing coal-processing plant in various confi gurations. The system features image-identifi cation technology, with the separator accurately identifying and separating coal and its components, without using water or any other medium. There is also no slime generation, with the TDS subsequently producing a higher yield of coarse coal at low operational cost at an increased return-on-investment, compared to conventional process systems. The fact that the TDS is not water-based not only reduces the footprint of mineral-processing plants due to the downscaling of the Dense Medium Separation (DMS) circuit as a result, it also means that slurry material is reduced drastically, thereby off ering a signifi cant environmental benefi t, in addition to overall cost-savings. The technology can process 300mm to 50mm and 150mm to 25mm raw coal, with an upper throughput of about 400tph. The higher tonnage output makes the TDS more effi cient compared to competitor dry sorter technology. Aury Africa is continuously striving to improve the technology’s separation capabilities in order to achieve coal sizing down to 12mm. The TDS was developed by Meiteng Technology in 2015. Aury Africa launched the technology locally at the South African Coal Processing Society’s biennial conference in Secunda in September 2017. At that time, three operating mines in China were using the equipment, which is now being commonly applied globally as far afi eld as Mongolia. The TDS is fully automated and modular, and also self- diagnostic. The longer the unit runs, the more accurate it becomes. “The margin of reject material compared to coal is reduced, as the TDS learns and adapts continuously,” says Aury Africa MD Sydney Parkhouse.  The TDS constitutes intelligent dry separation technology. Essentially coal is conveyed on an enclosed, single-layered Scraper winches are used in the mining of platinum and platinum group metals. They operate in tough underground conditions and are a key part of the extraction process as they scrape up and collect platinum particles and minerals. In South Africa, one of the world’s largest producers of platinum and associated platinum group metals uses winches extensively at its UTS plant in Rustenburg. The mining company saw a signifi cant improvement in the lifespan and performance of its winches when it switched to a multi-purpose, highly tacky lubricant, which has saved the company money on downtime and repair costs. The company is structured around fi ve mining operations and refi ning plants. At its UTS plant, when using winch grease and hydraulic oil on its 56 kW series scraper winches, the lifespan of 62  African Mining  November 2019 PROLONG WINCH LIFE WITH LUBRICATION Winches are an important part of platinum operations and should be properly maintained. www. africanmining.co.za