Market Survey on Copper - Indian Bureau of Mines

single pit: today the working area extends across 2.5km x 2.2km but is worked as
three pits: the Metcalf (within the original Morenci pit), the NWX (Northwest
Extension) and the Coronado.
Electric rotary rigs, mainly made by Bucyrus, drill blastholes and P&H 4100
and 2800 series electric rope shovels load the truck fleet. This includes more than 60
Caterpillar units, both 793 (218t capacity) and 797 (272t) models.Waste is mainly
used to backfill the Morenci pit, while the ore, which averaged 0.29% Cu in 2004, is
hauled to in-pit primary crushers. The new leaching-electrowinning capacity will be
incorporated into the existing complex, which is already the world's largest.
Processing
The Morenci and later Metcalf conventional concentrators supplied the
operation's own smelter until it shut down in 1984, and thereafter other Phelps
smelters. When hydrometallurgical processing started these two mills worked in
parallel with two leaching / solvent extraction operations and one electrowinning
tankhouse. The MFL conversion required an expansion of the hydrometallurgical
facilities to yield 365,000t/y of cathode copper, but led to the Metcalf concentrator
being closed and the Morenci unit being placed on care-and-maintenance until 2006.
While high-grade ore is conveyed to leach pads within the pit, the bulk of the
primary crusher output (63,500t/d of ore) is secondary crushed and conveyed to the
Stargo dump-leaching site. This ore is agglomerated for spreading by two Rahco
mobile stacking units. Leaching is bacterially assisted, with air blown into alternate
lifts.
The total heap and dump leach-liquor yield is 16,500m³/hr; copper recovery was
58.5% in 2003. Four SX plants – Central, Metcalfe, Stargo and Modoc – feed three
tankhouses (Central, Southside and Stargo). The new leaching-electrowinning
capacity will be incorporated into the existing complex, which is already the world's
largest.
Production
During 2006, Morenci mined 247Mt of ore, milled 4.1Mt grading 0.56% Cu,
placed 230.70Mt of ore onto leach pads, recovered 14,993t copper in concentrate and
electrowon 355,574t of copper cathode.
9. Bingham Canyon Copper Mine, USA
Located near Salt Lake City, Utah, USA, Bingham Canyon celebrated its 100th
anniversary in June 2003. The Bingham Canyon mine, Copperton concentrator and
Garfield smelter comprise one of the largest and most up-to-date integrated copper
operations in the world: major investments during the past 15 years have ensured
economically and environmentally sound operation. Cumulative copper output is now
about 17Mt, more than any other mine.
For much of its life, Bingham Canyon was owned by Kennecott Copper Corp.
However, during the post-1973 oil crisis shake-out, the company was acquired by
British Petroleum, then sold on to Rio Tinto, which operates Bingham Canyon
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