(MERAF) for the Base Metals Smelting Sector - CCME

• Hudson Bay Mining and Smelting is commissioning a $30 million
improvement system for gas handling in 2000/2001 which should result
in a 30% decrease in particulate matter releases
• The “Stack Tap Hole” at Noranda Horne, which was used to discharge
secondary gases from the Noranda Reactor and the Noranda
Continuous Converter, is no longer functional as of May 2000. The
gases are now collected and treated through a baghouse with lime
injection and directed through the converter stack (“Stack #2”)
• Reductions in releases at Noranda Horne have occurred due to
increasing percentage of matte being processed through the Noranda
continuous converter, since 1998 reported data.
• On March 28, 2002, Noranda announced the permanent closure of its
Gaspé smelter effective April 30, 2002.
4.4.1. Hudson Bay Mining & Smelting Co. Ltd., Flin Flon, Manitoba
The two measures which offer the greatest reduction potential are:
• Copper Smelter modernization including gas scrubbing and recovery of
sulphur dioxide to produce sulphuric acid.
• Processing the copper concentrate by using a hydrometallurgical
process.
In both cases, an accompanying significant increase in throughput would improve
the economics of the projects considerably, but such an increase would only be
possible if sufficient supply of economic concentrates were available.
The best option is the hydrometallurgical approach, which has the potential for
the maximum reduction of air emissions of pollutants while recovering elemental
sulphur that can be stored or shipped more economically and safely than
sulphuric acid. The implementation schedule would be longer than for a smelter
modernization, since this process still requires development and would have to
be tested first on a pilot plant scale. There are a number of pressure leaching
technologies under development. Given the state of the development of the
technology, installation of a facility by 2008 might not be achievable. Further, this
option could only be justified if it were feasible to increase the copper capacity to
approximately 150,000 tonnes per year. Current production at the Copper
Smelter is approximately 80,000 tonnes per year.
Copper smelter modernization using currently available proven technology has a
shorter implementation schedule, compared with a hydrometallurgical facility.
However, the minimum economic capacity of a modern copper smelter is
approximately 250,000 to 350,000 tonnes per year, considerably higher than the
current production. The SO 2 is converted to sulphuric acid (rather than sulphur)
which is more costly and difficult to ship. The proposed technology would be
flash smelting followed by flash converting, and a double absorption, contact acid
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