Plant gives mine new lease of life

THE Elizabeth Bay Mine near Luederitz was first commissioned in 1992 with a life expectancy of 10 years.

Last week, however, a new section of the plant was inaugurated which will enable the mine to treat previously untreatable diamond-bearing material and extend its life by another eight years. The original processing plant of the Elizabeth Bay Mine was designed to treat unconsolidated dry material only, but with the upgrade which saw the installation of the state-of-art Liberation Plant, will now be able to treat wet, cemented and clay-rich ores and also extract diamonds from large boulders as big as 1,1 metres.A section engineer at the mine, Waldo Koen, said the huge boulders could be crushed to a size of 200 mm by the primary crusher and then transferred to the secondary crusher, which deals with fragments of 200 mm and less.Koen said the plant processed some 14 tonnes of material a day and six million litres of seawater was used per hour during the processing.He said around 30 kg of gems were extracted in a year, of which 96 per cent were pure diamonds.The plant, which was upgraded at a cost of N$445 million, took 13 months to construct from the start to the commissioning of the primary liberation and 15 months for the secondary liberation section.The new additions, said Namdeb Managing Director Inge Zaamwani, would ensure a steady supply of some 400 000 carats a year.”This represents an increase of 315 per cent on the treatment capacity of the existing Elizabeth Bay plant, which is a great achievement indeed.By processing diamond-bearing materials in this way, the Liberation Plant is expected to treat approximately 1,9 million carats in the next eight years and provide employment to 296 employees who will be exposed to the latest and best technology in the diamond-processing industry,” said Zaamwani.At the occasion, Project Manager Ian Holl handed over control of the world-class treatment plant to Mine Manager Gerd Nissen.The original processing plant of the Elizabeth Bay Mine was designed to treat unconsolidated dry material only, but with the upgrade which saw the installation of the state-of-art Liberation Plant, will now be able to treat wet, cemented and clay-rich ores and also extract diamonds from large boulders as big as 1,1 metres.A section engineer at the mine, Waldo Koen, said the huge boulders could be crushed to a size of 200 mm by the primary crusher and then transferred to the secondary crusher, which deals with fragments of 200 mm and less.Koen said the plant processed some 14 tonnes of material a day and six million litres of seawater was used per hour during the processing.He said around 30 kg of gems were extracted in a year, of which 96 per cent were pure diamonds.The plant, which was upgraded at a cost of N$445 million, took 13 months to construct from the start to the commissioning of the primary liberation and 15 months for the secondary liberation section.The new additions, said Namdeb Managing Director Inge Zaamwani, would ensure a steady supply of some 400 000 carats a year.”This represents an increase of 315 per cent on the treatment capacity of the existing Elizabeth Bay plant, which is a great achievement indeed.By processing diamond-bearing materials in this way, the Liberation Plant is expected to treat approximately 1,9 million carats in the next eight years and provide employment to 296 employees who will be exposed to the latest and best technology in the diamond-processing industry,” said Zaamwani.At the occasion, Project Manager Ian Holl handed over control of the world-class treatment plant to Mine Manager Gerd Nissen.