The Nickel Mines at Lake Johnston

Lake Johnston Operations is a fly-in-fly-out operation (employees are flown in by plane for work) with approximately 150 permanent staff and contractors, that are mining the Emily Ann and Maggie Hays Nickel Deposits.

The deposits were discovered approximately 100m respectively 130m below the surface by diamond drilling in 1993 and 1997.

Both deposits will be mined from the surface via a decline developed at a 1 in 7 gradient from the bottom of a 30m deep resp. 35m deep boxcut.
The processing operation of the Emily Ann plant milling process involves the crushing of the material to a nominal 12mm size by means of a two stage crushing circuit (primary jaw crusher and secondary gyratory crusher).
The ore once crushed is transported by conveyor to the Fine Ore Bin (FOB).
Two conveyors at the base of the FOB are used to control the milling rate and transport the crushed ore to the 600kW ball mill.
The ore is ground in the ball mill to a nominal 130 microns.
The Nickel slurry passes through a bank of float cells with the recovered Nickel reporting to a concentrate thickener and subsequent storage tanks.
The thickened concentrate is then filtered (Larox Filter) to produce a final concentrate of 14.5%Ni.
The concentrate is trucked by road train to the port of Esperance where it is uploaded on to ships and transported to Canada for delivery to INCO.

Lake Johnston Operations take the protection of the local fauna and flora quiet serious. They are aware of some rare species and try to minimise and where necessary managed to lessen the disturbance.

It is also interesting to see this group of bins marked with the different items that they are meant for.
Usually in Australia they have 2 - 3 bins (normal rubbish, recycling and garden waste) so this is a quiet unique setup.



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Last updated: Thursday, 20.03.2008 12:32 PM