3
settler (E3). The solution flows are split with 1,000 m3/h
going to E1/E2 and 550 m3/hr flowing to E3. The organic
flows counter current to the incoming PLS starting from
E3 to E1. The barren copper solution, raffinate, flows to
the common raffinate pond. The loaded organic is then
subjected to a wash stage to remove entrained PLS solution
prior to proceeding to the stripping phase. MV employs a
single strip mixer/settler. The organic is stripped into the
strong electrolyte solution using a high acid solution. The
copper-rich solution is sent to the electrowinning process
(EW) which consists of 168 cells containing 1 m2 stainless
steel plate cathodes. Cathodes are harvested daily and are
95% LME Grade A quality. The resulting weak electrolyte
is recycled back to the organic stripping stage.
Cobaltiferous pyrite is present in the oxide ore, as well
as other cobaltiferous minerals that are generally a prod-
uct of naturally occurring oxidative weathering processes
acting on the original host pyrite. Some of these minerals
are soluble or partially soluble in the acid leaching system,
and due to the combined effects of acid leaching and inter-
nal recycling, the cobalt tenor in the leach solutions has
reached equilibrium values of between 250 and 400 parts
per million (ppm Co) depending on the characteristics of
the ore under leach.
Sulfide Concentrator and Tailings Storage Facility
Run of mine material is delivered to the primary crusher
(1400 × 2100 TS) by 240 t dump trucks which discharge
ore into the feed hopper (capacity of 330 t). Crushed prod-
uct discharges into a 330 t capacity intermediate hopper.
An apron feeder is located under this hopper to transfer the
material to a conveyor and then to the coarse ore stockpile.
The coarse ore stockpile has a live capacity of 16,150 t
(dry) and two apron feeders, located under the coarse ore
stockpile, to reclaim ore. The apron feeders discharge ore to
a transfer conveyor which feeds a single 34' × 20' 14 MW
semi-autogenous grinding mill (SAG) fitted with a vari-
able frequency drive (VFD). The SAG product is screened
via a trommel, and the oversize (pebbles) is recycled to the
SAG mill feed belt by two conveyors. The undersize from
the trommel discharges into the primary cyclone feed box,
which is connected to two horizontal centrifugal pumps
with variable speeds, one operating and one stand-by. The
pumps send the slurry to a hydrocyclone cluster (with 7
operating and 2 stand-by) which classifies the mill dis-
charge by size.
Hydrocyclone underflow (coarse) reports to a single
24' × 42' 14 MW Ball Mill with a VFD. Ball Mill prod-
uct is screened via a trommel with oversize ore and ball
scats discharging to a reclaim bunker at grade. Trommel
Figure 2. Mantoverde heap leach and SX/EW flowsheet (simplified)
settler (E3). The solution flows are split with 1,000 m3/h
going to E1/E2 and 550 m3/hr flowing to E3. The organic
flows counter current to the incoming PLS starting from
E3 to E1. The barren copper solution, raffinate, flows to
the common raffinate pond. The loaded organic is then
subjected to a wash stage to remove entrained PLS solution
prior to proceeding to the stripping phase. MV employs a
single strip mixer/settler. The organic is stripped into the
strong electrolyte solution using a high acid solution. The
copper-rich solution is sent to the electrowinning process
(EW) which consists of 168 cells containing 1 m2 stainless
steel plate cathodes. Cathodes are harvested daily and are
95% LME Grade A quality. The resulting weak electrolyte
is recycled back to the organic stripping stage.
Cobaltiferous pyrite is present in the oxide ore, as well
as other cobaltiferous minerals that are generally a prod-
uct of naturally occurring oxidative weathering processes
acting on the original host pyrite. Some of these minerals
are soluble or partially soluble in the acid leaching system,
and due to the combined effects of acid leaching and inter-
nal recycling, the cobalt tenor in the leach solutions has
reached equilibrium values of between 250 and 400 parts
per million (ppm Co) depending on the characteristics of
the ore under leach.
Sulfide Concentrator and Tailings Storage Facility
Run of mine material is delivered to the primary crusher
(1400 × 2100 TS) by 240 t dump trucks which discharge
ore into the feed hopper (capacity of 330 t). Crushed prod-
uct discharges into a 330 t capacity intermediate hopper.
An apron feeder is located under this hopper to transfer the
material to a conveyor and then to the coarse ore stockpile.
The coarse ore stockpile has a live capacity of 16,150 t
(dry) and two apron feeders, located under the coarse ore
stockpile, to reclaim ore. The apron feeders discharge ore to
a transfer conveyor which feeds a single 34' × 20' 14 MW
semi-autogenous grinding mill (SAG) fitted with a vari-
able frequency drive (VFD). The SAG product is screened
via a trommel, and the oversize (pebbles) is recycled to the
SAG mill feed belt by two conveyors. The undersize from
the trommel discharges into the primary cyclone feed box,
which is connected to two horizontal centrifugal pumps
with variable speeds, one operating and one stand-by. The
pumps send the slurry to a hydrocyclone cluster (with 7
operating and 2 stand-by) which classifies the mill dis-
charge by size.
Hydrocyclone underflow (coarse) reports to a single
24' × 42' 14 MW Ball Mill with a VFD. Ball Mill prod-
uct is screened via a trommel with oversize ore and ball
scats discharging to a reclaim bunker at grade. Trommel
Figure 2. Mantoverde heap leach and SX/EW flowsheet (simplified)