2014 Prof Gideon Chitombo year of keynote address in Chile

23 Dec 2014

The IMPC is a premier international congress in minerals processing and the international delegates can be in thousands. The 2014 International Mineral Processing Congress was held for the first time in Chile, from October 20th-24th.  The delegates were from more than 50 Countries. Professor Gideon Chitombo was an invited keynote speaker. His keynote was on the Next Generation of Cave mining and his abstract was:

Mining is a “continuous” stream of dependent activities including breakage of in-situ ore rock, initial handling of the broken ore rock at the face or drawpoints, further size reduction for the efficient transportation of the ore rock to a stockpile (s), and processing.  Over time, mining became two broad activities comprising either underground or in-pit activities, using a variety of in-situ breakage techniques and surface activities, using a variety of processing techniques dependent on mineralogy or grades. This artificial separation became exacerbated by these two broad activities being increasingly managed as separate mining cost centres as opposed to being managed as an integrated unit.  

In the case of the copper industry, mass mining, which is a subject of this keynote address, essentially started in 1903, when Daniel Jackling (a metallurgist) initiated the world’s first open-pit mining system at the Bingham Canyon porphyry copper deposit in Utah, at a mining rate of 6,000 tonnes per day of ore. The term mass mining has since been construed to mean large open pits and cave mining methods, including their variants. These methods are largely non-selective and involve the extraction of a heterogeneous range of commodities, the deposits of which are distributed unevenly in terms of qualities or grades as well as geological, geotechnical, hydrological and geometallurgical settings. 

Under suitable circumstances, mass mining can be relatively low cost, high volume, safe, highly mechanised and therefore profitable. As such, mass mining techniques became methods of choice for the mining of large scale and low grade deposits. Over time, and as mineral reserves closer to the surface are depleted, the deposits being found are tending to be of a lower grade, deeper in the ground and mixed with more impurities, as well as other factors that make extraction more difficult and costly.  Mass mining is moving rapidly into a new and less certain environment where revolutionary changes are required to effectively deal with the future mining challenges which are technical, economic and environmental (licence to operate). 

The keynote address presented  some of the current initiatives being considered for the next generation of both underground and surface mass mining systems in order to access and established mass mining methods much faster than current,  significantly reduce mining costs (CAPEX and OPEX), substantially increase productivity while being cognisant of license to operate issues.  The address was thus designed to solicit open discussions on how better integration of mining and processing can become a platform for the next generation of mass mining systems under considerations and how the integration can help the mining industry effectively deal with future technical, economic and environmental challenges.