Hydraulic Ore Hoisting
Hydraulic ore hoisting provides a potentially cost effective way of hoisting crushed ore from underground mines to the surface. This technology has been used for hoisting coal, gold ore, uranium ore, potash ore and waste rock in the form of a slurry. Hoisting depths can be up to 2000 m with tonnages up to 250 tph. The ore hoisting piping is either installed in an existing mine shaft or in dedicated boreholes.
Paterson & Cooke has extensive experience in the design of these systems and has completed a number of studies and projects including platinum, gold, copper and non-metallic ore hoisting systems. These systems are based on three chamber feeder system as well as positive displacement pumps. We have been involved in the analysis of a number of proposed hydraulic hoisting systems and can advise clients on ore feeder techniques and perform hydraulic and engineering analysis of hydraulic hoisting systems.
Laboratory test work is often required for a hydraulic hoisting system design and our services include pipe loop and wear test work.
Notable Projects
In the mid 1990’s the production at Brazil’s Mine Grande gold mine was limited by the outdated ore hoisting that resulted in high operating costs so a hydraulic hoisting system was identified as an economically attractive alternative. The system would convey 8mm crushed ore over a vertical distance of 2 222 m and a horizontal distance of 3 898 m at a production rate of 75 tonnes/hour. As this was a hard rock installation, the long term viability was dependent on the wear life of the system. Paterson & Cooke completed tests to determine the wear rates of a range of pipe lining materials. Pipeline wear tests were conducted on a range of materials that included several grades of polyurethane and wear resistant linings that were compared to ASTM A106 steel. (Cooke, R. (1996) "Pipeline Material Evaluation for the Mina Grande Hydrohoist System", 13th Int. Conf. on Slurry Handling and Pipeline Transport, Hydrotransport 13, South Africa, 3-5 September 1996.)
Hydraulic hoisting is not only suited to new shafts but is ideally suited to providing supplementary hoisting capacity to existing shafts that have reached the skip hoisting capacity limit. The main advantage for new shafts is the potential to significantly simplify underground rock handling and transportation. Paterson & Cooke completed an in-depth investigation on the requirements for a successful hydraulic hoisting installation on South African platinum mines and concluded that hydraulic hoisting is technically feasible and financially attractive for these operations. (Van den Berg, G. and R. Cooke (2005) “Hydraulic Hoisting Technology for Platinum Mines”, Platinum Adding Value Conference, SAIMM, Sun City, October 2004 - also published in the The Southern African Institute of Mining and Metallurgy, vol 105, No 5, pp 323 – 332, 2005.)
Case Studies