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Process Evaluation of the Rio Tinto Kennecott Underground
Expansion—A Case Study
Simon Timbillah, Stan Nelson, Isaac Boadi, Cory B Smith, John Moyo, Mike Hutton-Ashkenny
Rio Tinto–Kennecott Utah Copper, South Jordan, Utah
ABSTRACT: Copper demand is forecast to outstrip supply by 2030 due to a global shift towards renewable
power sources for electrification. The predicted copper demand to support electrification is approximately
double current production. Rio Tinto Kennecott has recently approved development capital of $553 m to
develop two underground mining areas (Lower Commercial and North Rim skarns) at its Bingham Canyon
operation to expand copper production. Future underground mine expansions into adjacent skarn orebodies are
currently being studied to add to this supply. Underground mining at Kennecott will therefore target different
ore bodies and consequently an integrated mining program is envisaged. The existing Copperton Concentrator
will process a blend of underground and open-pit ores, with the underground ore profiles changing more
dramatically as expansion projects are approved. Ore type and metallurgical process evaluation to understand
the processing of the proposed ore blends is therefore essential. This paper discusses recent results of this work
and the implications for processing future underground ore at Kennecott.
INTRODUCTION
Copper, an indispensable element in modern society that,
has witnessed a remarkable evolution in its global produc-
tion landscape over the past half-century. This transforma-
tive journey has been marked by both remarkable growth
and stark shifts in production patterns, particularly in the
United States. A hallmark of copper’s versatility is its ability
to seamlessly integrate into a myriad of applications, rang-
ing from the delicate circuitry of electronic devices to the
robust plumbing systems that underpin our homes. This
inherent adaptability has fueled its ubiquitous presence in
the construction of buildings, the operation of industrial
machinery, and the generation of electricity, making it a
cornerstone of modern infrastructure and technology.
Global copper production has embarked on an expo-
nential growth trajectory over the past 50 years, mirroring
the accelerated pace of technological advancement, urban-
ization, and infrastructure development. In 1970, global
copper mine production stood at approximately 8.5 mil-
lion tonnes, but by 2021, this figure had nearly tripled to
an astounding 22.5 million tonnes ([1], [2]). This remark-
able growth has been accompanied by a notable shift in
the geographical distribution of copper production, with
emerging economies in Latin America and Asia assuming a
more prominent role.
The United States, once a leading producer of copper,
has witnessed a significant decline in its share of global pro-
duction over the past decades. In 1970, the US accounted
for approximately 15% of global copper mine production,
but by 2021, this share had dwindled to a mere 3% [2,
3]. This decline can be attributed to a confluence of fac-
tors, including stringent environmental regulations, rising
production costs, and the depletion of traditional mining
sites [4, 5].
Despite this production decline, the United States
remains a significant consumer of copper, accounting for
Process Evaluation of the Rio Tinto Kennecott Underground
Expansion—A Case Study
Simon Timbillah, Stan Nelson, Isaac Boadi, Cory B Smith, John Moyo, Mike Hutton-Ashkenny
Rio Tinto–Kennecott Utah Copper, South Jordan, Utah
ABSTRACT: Copper demand is forecast to outstrip supply by 2030 due to a global shift towards renewable
power sources for electrification. The predicted copper demand to support electrification is approximately
double current production. Rio Tinto Kennecott has recently approved development capital of $553 m to
develop two underground mining areas (Lower Commercial and North Rim skarns) at its Bingham Canyon
operation to expand copper production. Future underground mine expansions into adjacent skarn orebodies are
currently being studied to add to this supply. Underground mining at Kennecott will therefore target different
ore bodies and consequently an integrated mining program is envisaged. The existing Copperton Concentrator
will process a blend of underground and open-pit ores, with the underground ore profiles changing more
dramatically as expansion projects are approved. Ore type and metallurgical process evaluation to understand
the processing of the proposed ore blends is therefore essential. This paper discusses recent results of this work
and the implications for processing future underground ore at Kennecott.
INTRODUCTION
Copper, an indispensable element in modern society that,
has witnessed a remarkable evolution in its global produc-
tion landscape over the past half-century. This transforma-
tive journey has been marked by both remarkable growth
and stark shifts in production patterns, particularly in the
United States. A hallmark of copper’s versatility is its ability
to seamlessly integrate into a myriad of applications, rang-
ing from the delicate circuitry of electronic devices to the
robust plumbing systems that underpin our homes. This
inherent adaptability has fueled its ubiquitous presence in
the construction of buildings, the operation of industrial
machinery, and the generation of electricity, making it a
cornerstone of modern infrastructure and technology.
Global copper production has embarked on an expo-
nential growth trajectory over the past 50 years, mirroring
the accelerated pace of technological advancement, urban-
ization, and infrastructure development. In 1970, global
copper mine production stood at approximately 8.5 mil-
lion tonnes, but by 2021, this figure had nearly tripled to
an astounding 22.5 million tonnes ([1], [2]). This remark-
able growth has been accompanied by a notable shift in
the geographical distribution of copper production, with
emerging economies in Latin America and Asia assuming a
more prominent role.
The United States, once a leading producer of copper,
has witnessed a significant decline in its share of global pro-
duction over the past decades. In 1970, the US accounted
for approximately 15% of global copper mine production,
but by 2021, this share had dwindled to a mere 3% [2,
3]. This decline can be attributed to a confluence of fac-
tors, including stringent environmental regulations, rising
production costs, and the depletion of traditional mining
sites [4, 5].
Despite this production decline, the United States
remains a significant consumer of copper, accounting for