July 17th, 2002

The CS500 ConSep ACACIA Reactor (above) was successfully installed and commissioned at How Mine's operation, which achieved an average of 99.5% recovery  within the one week of it's arrival on site.

BULAWAYO, Zimbabwe - The first African ConSep ACACIA Reactor has successfully been installed and commissioned at Independence Mining's How Mine operation, achieving an average of 99.5% recovery within one week of its arrival on site.

Peacocke, Simpson & Associates (PS&A) of Africa and ConSep Pty of Australia jointly carried out commissioning of the ConSep ACACIA Reactor for the treatment of the high- grade concentrates produced by the Knelson concentrators on site.

"This might in fact be a record time for installation and commissioning", said Perth-based Barrie Watson of ConSep Pty. "The mine staff have been extremely co-operative and helpful, with absolutely no mechanical or process problems encountered".

The first use of the ConSep ACACIA Reactor after installation and connection achieved recovery of 98.5%, followed by 99.3% recovery on the second run. Recoveries since then were consistently in excess of 99%, giving an average recovery of 99.5%.

The How Mine unit joins six other ConSep ACACIA Reactors worldwide, all of which consistently achieve recoveries over 98% and faultlessly commissioned within days of installation.

The ConSep ACACIA Reactor was designed as a skid-mounted modular system for ease of installation and operation and uses an upward- flow fluidized bed technology to process the concentrates. With two standard centrifugal pumps as its only moving parts, the ConSep ACACIA Reactor avoids the frequent and costly maintenance problems suffered by complex rolled-drum intense cyanide systems. In addition, the production of clarified liquor overflow eliminates the thickening and clarifying systems necessary with rolled drums, and successfully removes all tramp iron during flushing out of concentrate batches.

"This has been a long-awaited development", said Peter Simpson of PS&A. "The Achilles heel of gravity systems has always been the treatment of high grade concentrates. Previous systems have used physical re-dressing such as tabling and amalgamation, which suffer from poor efficiency, security concerns and environmental problems. Other commercial intense cyanide systems, from our experience, are also fraught with problems. The development of the ACACIA as a simple, efficient and effective intense cyanide system opens a new chapter in our history" continued Peter.

The ConSep ACACIA Reactor was jointly developed over a five-year period by Anglogold Australia and ConSep Pty. Ltd, Knelson Concentrator's Australian licensees, for intense cyanidation treatment of high grade gravity concentrates arising from Knelson Concentrators or other devices. The ACACIA is marketed and supported in Zimbabwe by Peacocke, Simpson & Associates of Harare and throughout most parts of Africa by Johannesburg-based Knelson Concentrators Africa.

"The addition of the ConSep ACACIA Reactor to our product offering helps us solve a critical problem that many customers have experienced in treating gold concentrates from our centrifugal mineral separators" said Brett Knelson, Knelson's V.P. of Operations and Business Development. "Gold rooms using labour-intensive devices such as mineral tables often suffer with recoveries that are only in the 50-70% range. The ACACIA has proven to dramatically improve these recoveries with a simple alternative that can be fully automated and integrated with a Knelson Concentrator installation. We are confident that our global ACACIA marketing partnership with ConSep, in conjunction with Knelson's agent support network, will make this technology readily available and extremely attractive to our customers worldwide".

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