Murrin murrin

The Murrin Murrin nickel, cobalt and magnesium mine that is located 50 kilometres east of Leonora in Western Australia's North Eastern Goldfields Region, is owned and operated by Minara Resources, a wholly owned subsidiary of Glencore Xstrata. It was originally commissioned by Anaconda Nickel Limited.

Murrin Murrin Mine Commissioned in 1999
The Murrin Murrin Mine, one of Australia's leading nickel producers, began production in 1999, mining and processing laterite ore. Nickel laterite is the concentration of cobalt and nickel in silicate minerals, usually clay, caused by extensive weathering of ultramafic rocks rich in olivine. Three quarters of the world's nickel is discovered in laterites.

Murrin Murrin, an Open Cut Mining Operation
The Murrin Murrin Mine is an open pit mining operation using conventional open cut mining methods to remove the ore. The ore is treated on-site at the processing plant that exposes it to pressure acid leaching alongside sulphide precipitation, nickel and cobalt refining. Ammonium Sulphate is produced as a by-product of the refining process.

Estimate life of Mine of 30 Years for the Murrin Murrin Mine
Murrin Murrin production figures for 2011 showed it produced 30,000 tonnes of nickel and 2,100 tonnes of cobalt. It finished the year with a resource base of 268 million tonnes and reserves of 186 million tonnes, giving the mine a life of 30 to 40 years. Minara has used engineering solutions and technological improvements to improve the reliability and throughput of its processing plant which has resulted an increase of its cobalt and nickel levels. Minara's leaching technology also allows it to process low grade ores cost effectively. The laterite hosted orebodies at the Murrin Murrin Mine are mostly about 20 metres in depth lying under 10 metres of overburden.

Murrin Murrin, the Largest Single Site Employer in Western Australia
Open cut mining at the Murrin Murrin Mine benefits from low mining costs because of its favourable stripping ratios. The mining fleet consists of Komatsu haulage trucks and Hitachi hydraulic excavators. It employs around 1,000 mining personnel who are flown in and out of the mine site to complete their rosters. While on the job, the workers are housed in modern village style accommodation. The Murrin Murrin Mine is one of the largest single site employers in Western Australia.

State of Art Ore Processing at the Murrin Murrin Treatment Plant
The ore processing technology practised at the Murrin Murrin Mine incorporates the Sherritt International Pressure Acid Leach (PAL) method. This technology recovers cobalt and nickel by means of a Fluor Daniel designed and engineered treatment plant. This methodology requires the crushed and slurried ore to be pressure leached using sulphuric acid. The slurry mill discharges its produce into a classification screen. Oversize slurry is stored in the tailings dam and under-size slurry pumped into the autoclave feed slurry storage tanks.

When the PAL area receives the slurry feed it heats it to a temperature of 225 degrees Celsius and mixes it with hot sulphuric acid inside four titanium lined autoclaves. This causes the cobalt and nickel to be leached into the solution. Precipitated aluminium and iron tailings are washed and stored in the tailings dam. The autoclave slurry is discharged to a counter- current decantation washing area where it undergoes mixing with water that has been flash-steam heated. This process produces a clear solution of cobalt and nickel. The solution is then further treated in an autoclave by pure oxygen. Iron, copper and zinc impurities are then removed, Cobalt is separated and its concentrate fed into the cobalt hydrogen reduction area.
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