NewsPolyMet Mining Corp. has successfully completed its second and final continuous pilot plant test at SGS Lakefield Research Laboratories in Lakefield, Ont. Pilot plant results are expected by the end of November and will be included in the company's definitive feasibility study, which is due for completion by March, 2006. SGS Lakefield is also producing certain specialty products at the request of prospective off-take companies.
Metallurgical testing was conducted on a 40-tonne bulk sample of large diameter diamond drill core collected from the NorthMet deposit during January, February and March of this year. While adding more knowledge and understanding of the deposit, the drilling was specifically designed to provide a representative sample of material to be mined within the first 10 years of production.
"Preliminary results indicate recoveries of copper, nickel-cobalt and platinum group metal precipitates, using our chloride assisted autoclave leach process, are in-line with results of previous bench and pilot-scale testing. These test results will most certainly provide a sound basis for design and engineering of our planned commercial-scale process facility in Minnesota," said William Murray, PolyMet president and chief executive officer.
Mr. Murray added that the recent test work also modelled process improvements compared to the 1999 pilot plant campaign and targeted the production of refined copper cathode metal and other products such a pure nickel hydroxide concentrate to meet the requirements of prospective metals off-take partners.
Data required for environmental review and permitting were also collected as an integral part of the metallurgical testing. PolyMet's environmentally friendly hydrometallurgical process produces minimal air and water emissions, and, in the case of copper production, consumes only about half the amount of energy of conventional copper smelting.
A draft report on the testing is expected from SGS Lakefield before the end of October with a final report due four weeks later. The results of this and previous metallurgical testing will form the basis of process design and engineering by Bateman Engineering Pty Ltd. and will be incorporated into PolyMet's definitive feasibility study (DFS), which is due for completion in the spring of 2006.
"Given the consistency of recent test work results, we expect the DFS to provide a high level of confidence in the commercial viability of the NorthMet project," Mr. Murray said.
PolyMet recently announced early exercise of its option to assume ownership of large ore processing plant facilities from Cliffs Erie, LLC, in its quest to establish Minnesota's first major base and precious metals mining operation. The project is scheduled for commercial operations in early 2008.