Faster way to undertake mineral and ore analysis

Researchers from Brock University in Ontario are working with a Mississauga company to develop technology that dramatically speeds up mineral and ore analysis while reducing its impact on the environment. When Brock alumnus Ravi Kanipayor, together with the technology company Chemquant, invented ColdBlock, they began working with a research group at Brock University to analyse environmental samples, such as contaminated soils, biosolids and sludges. The analysis process involves dissolving samples – called ‘digestion’ – to measure the contaminant metals in the samples.

The group found that it took 15 minutes or less to digest the samples when using ColdBlock. Current conventional methods take up to four hours to digest samples using a technology often called hot block, which is basically a hot plate.

“Pretty soon after we started to get these excellent results for environmental samples, we realized that this technique could have broader applications,” says chemistry Professor Ian Brindle.

Brindle and his research team have partnered with Chemquant to take the new technology one step further. “That’s when we started looking at the potential for ColdBlock to be used for mining samples,” he says.

With current technology, it can take more than 16 hours to dissolve some of these mining samples, with methods that use toxic acids and acids that form explosive compounds.

ColdBlock uses focused infrared energy to heat the sample in an acid mixture. “And this is the major difference: conventional methods heat the acid in which the sample sits,” says Brindle. “Together with the invention of new chemistry for sample preparation, this has given us a real boost in efficiency.” He explains that ColdBlock technology is also ‘green’ in a number of important aspects.

Sample treatment eliminates the need for perchloric acid, an acid that can form explosive metal salts, and, in some cases, eliminates the need for hydrofluoric acid, which is easily absorbed through the skin and is very toxic.

In addition, because the temperature is well controlled, there is little need to replace acids that, in the case of conventional digestions, are boiled off into the environment.

From a productivity perspective, the ColdBlock can save huge amounts of time, says Brindle. “Preparation of the difficult samples that normally take 16 hours, such as chromite, can be prepared in less than 15 minutes using ColdBlock technology.” Chromite is an ore of great interest in Canada following the discovery of an enormous deposit of chromite in northwestern Ontario.

Brindle’s group has just received a grant in cash and in-kind totaling C$580,000 from a group of funders that includes the Natural Sciences and Engineering Research Council of Canada, Ontario Centres for Excellence, the Centre of Excellence for Mining Innovation, Barrick Gold, and Chemquant Technologies (now operating as ColdBlock Technologies).

Preliminary results on mining samples have been very encouraging, says Brindle. “The ColdBlock technology, combined with innovative chemistry, has been able to deliver accurate results for a number of samples, including chromite, sulphide ores, such as those from the nickel belt, and iron ore,” says Brindle. “But the technology needs to be upgraded to enable the sample preparation to be performed using automation, which should enable large number of samples to be processed as the service laboratories perform thousands of samples a week.

“So that’s what this grant is about,” Brindle explains. “It’s about automating the technology and upgrading the ‘recipe’ book of sample types that can be prepared by this system.”

Brindle says that samples could be analysed at the mine site. “It is safer and uses smaller amounts of acids,” he says. “And if the instruments that measure the metals in these samples can operate in remote locations, almost real-time results could be obtained, which would improve efficiency.”

Shantanu Mittal, Business Development Manager with Ontario Centres of Excellence, calls ColdBlock a technology with the potential to have a serious impact on the mining and environmental sector. “OCE first supported this technology through our Technical Problem Solving (TPS) program where we helped validate the technology through a collaboration with Dr. Brindle’s group at Brock University,” he recalls. “We are very happy with the progress the industry and academic partners have made in making this technology ready for commercialisation.”

“We have seen some promising preliminary results with ColdBlock technology,” says Yeonuk Choi, a senior manager with Barrick Gold’s Strategic Technology Solutions. “We look forward to exploring with Brock improvements in delivering fast and accurate results for gold and other metals in the ores from our mines.”

Chemquant Chief Executive Officer Don Saunders explains that the technology has wide applications. “ColdBlock Technologies believes the high energy acid digestion process by ColdBlock will deliver not only rapid digestions with superior performance characteristics but, through automation, will be beneficial for small and large laboratories alike, in mining, agriculture, forestry, food, environmental, and pharmaceutical applications,” he says.