Faculty of Science

Squeezing revenue out of a rock (Part 2)

Canada has the world’s second largest mining supply sector. But mine development and mineral extraction are both complex and expensive endeavors with total capital expenditures in 2011 exceeding 11 billion dollars. To continue to maintain Canada’s strong competitive edge, the use of novel tools for developing innovative process strategies to increase ore extraction productivity and reduce the overall costs of mine development must be carried out.

The process of recovering metals from ore involves crushing mined rock down to fine grains or to flour-like consistency and putting it in large water-filled tanks equipped with rapidly spinning impellers and air jets. Chemicals are added to the stirring, bubbling mixture so that the desired minerals are no longer attracted to water. The desired minerals attach to the surrounding air bubbles and float to the top in a froth where they are collected and processed in order to extract the desired metal.

Traditionally, optimizing mineral floatation has been based primarily on repetitive trials in which different sets of chemicals are added to the brew at varying points in the process. Now, Western researcher Dr. Brian Hart will use the advanced technologies available at Surface Science Western to track both the composition and changes to the surface of the fine grains during the floatation process. This will help determine the most efficient process for extracting the highest percentage of the desired mineral in the least amount of time.

Each of the eight mining companies participating in this four-year, 1.5 million dollar project will present their individual challenges to the research team.  According to Hart, “they will present a  variety of raw materials with differing mineralogy, water chemistry and reagents and, while each case will be different,  the process employed is the same and we are finding ways to use our advanced tools in novel ways to optimize their respective processes”. Hart and his collaborators, Qi Liu, ZhengheXu, Qingxia Liu and HongboZeng from the University of Alberta and FaicalLarachi from the Université de Laval will address the challenges of each mine on a case-by case basis in order, ultimately, to develop process improvement strategies to enhance metal recovery and generate revenue required to ensure our continued competitive advantage in this sector.