622 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
based on reported energy values, the report indicated a
potential 30% energy saving by using “best practices” and
a 75% savings as a practical minimum (DOE, 2007). The
results emphasize that reducing comminution energy will
have the greatest impact on reducing overall mine energy
consumption.
In 2018, Hille (2018) proposed the “mineral process-
ing flowsheet of the future” concept that includes these
enabling technologies. The flowsheet includes sensor-based
bulk ore and particle sorting to reject waste as early as pos-
sible in the material handling stream to reduce the amount
of material reported to water and energy-intensive grinding
and flotation processes. In 2023, van de Vijfeijken et al.
(2023) proposed a varied version of the “Flowsheet of the
Future.” The proposed flowsheet replaces SAG mills with
the more energy-efficient High Pressure Grinding Rolls
(HPGRs) technology, followed by coarse grinding in stirred
mills and coarse particle mineral separation (rougher flota-
tion). The consequence is that a large portion of the barren
coarse fraction reports to the final tailings without exces-
sive grinding in the secondary grinding stage, thus only the
mineralized particles report to concentrate regrind (using
stirred mills) and final stages of mineral separation (cleaner
flotation). The process includes water recovery for re-use
with dewatering screens of the coarse particle flotation
tailings as well as thickening and filtration of fine flotation
tailings. The overall consequence is less water, less energy,
and a smaller and physically stable tailings storage facility.
For the past 15 years, UBC has focused research aimed
at advanced technologies that enable a flowsheet includ-
ing bulk ore sorting, particle sorting, HPGR and stirred
mill comminution. Several of the research programs were
conducted with operating sites with convention open pit,
SABC and flotation operation. Based on data collected, this
study will compare the impacts of these technologies on
water usage, energy consumption and resource utilization.
The study does not include assessment of the capital and
operating costs.
BASE CASE FLOWSHEET—
COPPER PORPHYRY OPERATION
The considered copper mining operation is an open pit
mine excavating 150,000 tpd of combined waste and ore
with a strip ratio of 2:1 such that 50,000 tpd reports to a
conventional SABC and flotation circuit. The average ore
grade is 0.3% copper, and the mining cut-off grade is 0.15%
Cu. Following primary crushing, the ore is fed to a SAG
mill operated in closed circuit with a pebble mill. SAG cir-
cuit product reports to ball mill grinding ahead of rougher
flotation followed by regrinding and cleaner flotation to
Figure 1. Conventional base case flowsheet
based on reported energy values, the report indicated a
potential 30% energy saving by using “best practices” and
a 75% savings as a practical minimum (DOE, 2007). The
results emphasize that reducing comminution energy will
have the greatest impact on reducing overall mine energy
consumption.
In 2018, Hille (2018) proposed the “mineral process-
ing flowsheet of the future” concept that includes these
enabling technologies. The flowsheet includes sensor-based
bulk ore and particle sorting to reject waste as early as pos-
sible in the material handling stream to reduce the amount
of material reported to water and energy-intensive grinding
and flotation processes. In 2023, van de Vijfeijken et al.
(2023) proposed a varied version of the “Flowsheet of the
Future.” The proposed flowsheet replaces SAG mills with
the more energy-efficient High Pressure Grinding Rolls
(HPGRs) technology, followed by coarse grinding in stirred
mills and coarse particle mineral separation (rougher flota-
tion). The consequence is that a large portion of the barren
coarse fraction reports to the final tailings without exces-
sive grinding in the secondary grinding stage, thus only the
mineralized particles report to concentrate regrind (using
stirred mills) and final stages of mineral separation (cleaner
flotation). The process includes water recovery for re-use
with dewatering screens of the coarse particle flotation
tailings as well as thickening and filtration of fine flotation
tailings. The overall consequence is less water, less energy,
and a smaller and physically stable tailings storage facility.
For the past 15 years, UBC has focused research aimed
at advanced technologies that enable a flowsheet includ-
ing bulk ore sorting, particle sorting, HPGR and stirred
mill comminution. Several of the research programs were
conducted with operating sites with convention open pit,
SABC and flotation operation. Based on data collected, this
study will compare the impacts of these technologies on
water usage, energy consumption and resource utilization.
The study does not include assessment of the capital and
operating costs.
BASE CASE FLOWSHEET—
COPPER PORPHYRY OPERATION
The considered copper mining operation is an open pit
mine excavating 150,000 tpd of combined waste and ore
with a strip ratio of 2:1 such that 50,000 tpd reports to a
conventional SABC and flotation circuit. The average ore
grade is 0.3% copper, and the mining cut-off grade is 0.15%
Cu. Following primary crushing, the ore is fed to a SAG
mill operated in closed circuit with a pebble mill. SAG cir-
cuit product reports to ball mill grinding ahead of rougher
flotation followed by regrinding and cleaner flotation to
Figure 1. Conventional base case flowsheet