Spotlight on Minerals to Metals: mining for the future

SPOTLIGHT: MINERALS TO METALS
Why can’t we do without?
“Africa is not just the cradle of
humankind but also the cradle of
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Towards
less waste
One of the most pressing
problems facing mining is one
in which Minerals to Metals has
done a great deal of research:
how to better deal with mine
waste?
Mine waste currently
accounts for 70 to 90% of
all ore extracted. According
to UCT Associate Professor
Jennifer Broadhurst, as long as
there are tailings dams – which
are used to store waste products
of mining operations – the
long-term risks of pollution and
catastrophic failure events will
persist. Take, for example, the
recent environmental and social
impacts of the Brumadinho
dam disaster in Brazil that
killed hundreds of people.
“In the past, tailings dams
have led to dust in the air,
seepage into the soil and
pollution plumes,” she says.
“Even in the case of new
facilities, these repositories of
waste are hard to rehabilitate.”
And because of inefficiencies
in extraction processes, tailings
dams have taken a lot of
water and energy to produce
and often still hold valuable
resources that are lost.
Minerals to Metals is
working on a variety of projects
that aim for minimal waste.
“Instead of stockpiling waste,
let’s use it in a myriad of other
ways, from bulk stock in the
construction industry to the
production of stone paper,
bricks and ceramics, and even
fabricated soils created from
coal waste,” she explains.
PHOTOGRAPHS: WIKI COMMMONS; SHUTTERSTOCK
I
think globally there is a growing
realisation that we have to
find more sustainable ways
to mine, in which the sector
moves from an extractive model
towards a developmental one,” says
UCT Associate Professor Jennifer
Broadhurst.
Broadhurst is part of the core
leadership team of the Minerals to
Metals Initiative, a UCT signature
theme established in 2007 that aims
to integrate and expand capacity
in minerals beneficiation research.
Or, as Professor Jochen Petersen,
another member of the leadership
team explains it, “We aim to create a
platform for sustainable development
in Africa through minerals and metals.”
Petersen describes the current
challenges facing mining as complex.
“Whatever solutions we use in the
future have to be grounded in an
understanding of the complex nature
of the problems we face today.
“Mining remains important and
necessary, but it must also tread lightly
when it comes to people and the
planet.”
mining,” says Broadhurst. “Modern
mining might have emerged during
the 17th century but people were
mining in Africa centuries before that.”
The oldest mine in the world, she
says, is in Eswatini. People there were
mining haematite – an important ore
of iron – 43 000 years ago, around
the time that humans were reaching
Europe. According to Broadhurst and
Petersen, metals and the minerals
they are derived from have been
indispensable to human development
ever since.
“Metals and minerals are not just
found in the places you might expect,
like your smartphone. These materials
are in everything we use; even your
toothpaste contains about six mined
minerals,” says Broadhurst.
Petersen explains that some people
argue that we no longer need to mine
because we have other sources of
energy – wind and solar power – or
because we can replace minerals with
other materials, such as carbon fibre.
But that thinking is misconceived.
“In fact, mining is fuelling the green
economy. This is because the complex
minerals we mine help to build the
infrastructure that supports renewable
energy and the move away from coal,”
he says.
Mining is integral to the generation,
storage and transport of green energy.
For example, new commodities
like lithium, cobalt and rare earth
metals are used in batteries and
communications equipment. Rare
earths, together with more established
commodities, such as aluminium and
copper, are used in wind turbines and
electric cars.
“Many of these minerals are found
in South Africa,” Broadhurst explains.
“The platinum-group metals (including
platinum, palladium, rhodium and
others) are used as exhaust catalysts in
petrol and diesel vehicles, but they are
also used in fuel cells.”

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