An Ontario company, Enpar Technologies Inc., says it has developed a new hydrometallurgical alternative for the recovery of nickel from sulphide ore and tailings. The company has filed patent applications for the technology and says it is in discussions with several mining companies to develop strategic alliances, joint ventures and licensing agreements.
Enpar Technologies President and CEO Dr. Gene Shelp says there are hundreds of millions of tonnes of tailings grading from .3 to 1.0 per cent nickel in the Sudbury area. "You could be looking at tens of billions of dollars if our process lives up to what we say it will do."
The so-called ExtrEL leaching system uses "electrochemistry to enhance the oxidation of sulphide minerals and the subsequent solubility of metals of economic interest."
The company, based in Guelph, Ontario, has been working on the technology for more than a decade and claims to have made a decisive research breakthrough within the last year.
Shelp, who has a PhD in Geochemistry and hails from Kirkland Lake, says the company plans to develop a larger pilot unit in its labs in early 2007 and begin planning for a demonstration plant capable of producing 100 tonnes of nickel per year.
"Sudbury would be the logical place for it," said Shelp. "We have a job to demonstrate to interested parties that we can deliver and we look forward to the challenge."
Assuming capital costs of $750,000, another $750,000 for annual operating costs and $3.2 million in revenue, "you could recoup your capital costs and still produce a profit of $1.7 million in the first year. In the second year, you'd be generating a profit of $2.4 to $2.5 million," said Shelp.
"With nickel prices so high, nickel sulphide tailings are basically an ore deposit now. It's not waste anymore. And it's already been mined and crushed. All of the big money has been spent. That's why it's so exciting."
Shelp is confident that the technology will be equally effective for processing mill concentrates.
"From what I've been told, they're not building new smelters, so if you can come up with a hydrometallurgical approach that allows every nickel mining company to process its own ore on site, that may give many opportunities to smaller companies because right now they're at the mercy of a few companies that own the last remaining 11 smelters and they have all kinds of surcharges upon surcharges.
"I think it's great for the mining industry if we can deliver on what we say we can," said Shelp.
Metallurgists familiar with the challenge of developing a hydrometallurgical process for nickel sulphide ore were reluctant to comment on Enpar Technology's claims.
"We know there's a lot of metal in the tailings," said Gregg Gavin, Manager of Production Planning and Process Metallurgy at CVRD Inco. "The question is whether you can take what you get and put it in a form that is valuable to someone at a price that is more than you spent on it. Getting the metal out of the ore or into a solution is only the first step."
CVRD Inco commissioned a $200 million hydrometallurgical demonstration plant in Argentia, Newfoundland, in October 2005 and plans to assess the technical and economic feasibility of its technology late next year.
Toronto-based LionOre Mining International also hopes to commercialize a hydrometallurgical process for treating metal sulphide concentrates and has been operating a demonstration plant at its Tati Nickel operation in Botswana since 2004. LionOre's Activox process, acquired as part of its purchase of Australian-based Western Minerals Technology, uses a combination of ultra fine grinding and pressure oxidation.
Hydrometallurgy potentially offers several advantages over conventional smelters. Plants can be smaller, less costly to build and are more environmentally friendly due to the elimination of sulphur dioxide emissions, say proponents.
Enpar has developed a number of electrochemical water treatment technologies addressing health and environmental issues related to the management of wastewater and drinking water. Its AmdEL Electrochemical Cover technology, designed to prevent acid mine drainage from tailings facilities, has been tested at Xstrata's Hardy Mine and is now undergoing further tests by the U.S. Environmental Protection Agency at the Golden Sunset Mine in Butte, Montana.