3
true for all other mills. Such a Zn-converted Cu scavenger
now runs as passive mechanical Cu rougher scavengers but
can have reagents added to Zn condition tank and become
a chemical scavenger. Thus, a successful Cu rougher scav-
enger at Buick can be instrumental for all mills to signifi-
cantly enhance Zn rougher as Cu rougher scavenger for Cu
specials.
The copper rougher scavenger was renovated from an
idled copper pre-float circuit, specifically the lower rougher
section (see Figure 2). The pre-float circuit was used to pro-
cess high-grade copper ores that would exceed the capacity
of the lead circuit, which was also used as a copper cir-
cuit. This parallel design effectively split the flotation feed
to the pre-float circuit, making it an excellent fit for han-
dling higher-grade ores. However, as high-grade copper ore
availability decreased over time, the pre-float circuit was left
idled for years. Although the pre-float circuit demonstrated
a clear copper flotation process, detailed descriptions fall
beyond the scope of this article. Copper rougher scavengers
are now universally employed in copper mineral process-
ing to boost copper recovery, especially from complex low-
grade ores. Therefore, converting the idled pre-float circuit
into a copper rougher scavenger became both a necessary
and optimal solution.
Extensive repairs, renovation, and upgrades were made.
The MCC (Motor Control Center) was inspected and
upgraded, while the flotation cells, their rotors and mix-
ers, and the basement drop boxes and staging boxes were
cleaned up and repaired with extensive welding work. Four
horizontal process pumps were repaired for scavenger oper-
ations—two large tail (lead concentrate) pumps, one feed
pump, and one pump for transferring froth to the copper
rougher feed box. Extensive HDPE piping, electrical work,
instrumentation, and motor wiring to the PLC and DCS
were performed. Very importantly, a pair of large stainless
isolation valves and feed valves were installed and pneumat-
ically controlled, allowing for the opening and operation
of the scavenger or closure when copper grades were too
Figure 2. Buick mill Cu Pre-Float Circuit
true for all other mills. Such a Zn-converted Cu scavenger
now runs as passive mechanical Cu rougher scavengers but
can have reagents added to Zn condition tank and become
a chemical scavenger. Thus, a successful Cu rougher scav-
enger at Buick can be instrumental for all mills to signifi-
cantly enhance Zn rougher as Cu rougher scavenger for Cu
specials.
The copper rougher scavenger was renovated from an
idled copper pre-float circuit, specifically the lower rougher
section (see Figure 2). The pre-float circuit was used to pro-
cess high-grade copper ores that would exceed the capacity
of the lead circuit, which was also used as a copper cir-
cuit. This parallel design effectively split the flotation feed
to the pre-float circuit, making it an excellent fit for han-
dling higher-grade ores. However, as high-grade copper ore
availability decreased over time, the pre-float circuit was left
idled for years. Although the pre-float circuit demonstrated
a clear copper flotation process, detailed descriptions fall
beyond the scope of this article. Copper rougher scavengers
are now universally employed in copper mineral process-
ing to boost copper recovery, especially from complex low-
grade ores. Therefore, converting the idled pre-float circuit
into a copper rougher scavenger became both a necessary
and optimal solution.
Extensive repairs, renovation, and upgrades were made.
The MCC (Motor Control Center) was inspected and
upgraded, while the flotation cells, their rotors and mix-
ers, and the basement drop boxes and staging boxes were
cleaned up and repaired with extensive welding work. Four
horizontal process pumps were repaired for scavenger oper-
ations—two large tail (lead concentrate) pumps, one feed
pump, and one pump for transferring froth to the copper
rougher feed box. Extensive HDPE piping, electrical work,
instrumentation, and motor wiring to the PLC and DCS
were performed. Very importantly, a pair of large stainless
isolation valves and feed valves were installed and pneumat-
ically controlled, allowing for the opening and operation
of the scavenger or closure when copper grades were too
Figure 2. Buick mill Cu Pre-Float Circuit