Market Survey on Copper - Indian Bureau of Mines

ii) Malanjkhand Copper Project
The capacity of Malanjkhand Copper Project mine output is 2 million
tpy. The average copper content in the ore is 1.2 to 1.5%.
Process Description
Crushing: ROM up to 1,200 mm size is crushed to 150 mm size in a
gyratory crusher and the crushed product is conveyed to 18,000 tonnes capacity
open stockpile. The coarse material is screened over double deck screens with
(-) 90 mm and (-) 40 mm openings. The (-) 40 mm product goes to surgebin
located above the Symon's cone tertiary crusher and screen oversize is crushed
in secondary cone crusher. The crushed product is also taken to the surge bin.
From the surge bin, the ore is drawn by belt feeders for feeding three single
screens with 12 mm openings. The undersize is sent to fine ore bin (10,000
tonnes capacity) and oversize goes to surge bin.
Grinding : 12 mm product from fine ore bin drawn by eight belt feeders
to conveyors for feeding four overflow type ball mill in closed circuit with eight
hydrocyclones, i.e. each ball mill is in closed circuit with two cyclones. The
cyclone overflow (30% solids) with 60% of 200 mesh fraction goes through
distribution to flotation section.
Flotation : Flotation cell bank contains cells for rougher and scavenger
flotation. The rougher tailing is scavenged. The rougher float is cleaned once
and cleaner tails along with scavenger concentrate are recycled to rougher cells.
The first cleaner concentrate is cleaned once more and second cleaner tailings
are recycled to first cleaner cells. The second cleaner concentrate constitutes
the final copper concentrate. The reagents used are 70 g/t of Methyl Isobutyl
Carbinol (MIBC), 48 cells each of 8.5 m 3 capacity used in rougher and
scavenger flotation. 24 and 16 cells each of 1.7 m 3 capacity are used in first and
second cleaner flotation, respectively.
Thickening and Filtration: The second cleaner concentrate slurry is
pumped to a 25 m diameter thickener. The thickener underflow is pumped to 2
disc filter units each having 6 discs with 2.7 m dia. The filter cake (concentrate)
contains about 12 to 13% moisture and is sun dried. The dried concentrate is
dispatched to Khetri and Ghatsila smelters. Copper content in the concentrate
was 25.79% in 2008-09.
3.2.7 Copper Smelters in India
Till 1997, the only producer of primary refined copper in India was
HCL. After economic liberalisation, Sterlite Industries Ltd. (SIL) and Birla
Copper (Hindalco Industries Ltd.), started producing refined copper from
imported/indigenous concentrates.
The smelters of HCL are located at Khetri in Rajasthan and Ghatsila in
Singhbhum district Jharkhand, while the smelter of SIL is located at Tuticorin,
Tamil Nadu and that of Birla Copper at Dahej, Gujarat.
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