OPERATIONS
MINE VENTILATION
A MATTER OF LIFE AND DEATH
Compiled by Tarina Coetzee
A well-functioning heating,
ventilation and air conditioning
(HVAC) system in a mine is
non-negotiable when it comes
to creating a safe working
environment for mine workers.
L
ike with any HVAC system, it is imperative to do
your homework when you design an HVAC system
for a mine.
Why does a mine need cooling in the first place?
A mine gets hot as the temperature of the rock increases as you
go deeper. Considering that the crust is floating on the mantle
– a molten layer of magma – and the thickness of the crust
is about 60km, it stands to reason that rock temperature will
increase with depth. This increase in temperature means that
the rock adds heat to the shafts and tunnels in a mine. A well-
established deep level mine can have virgin rock temperatures
of between 500C and 600C.
“Clearly, people and equipment cannot work in conditions like
this, so the air in the tunnels and shafts needs to be cooled.
Heating is rarely, if ever, used. Perhaps in Canada or Siberia, but
really, who wants to work there,” says Russell Hattingh, regional
manager of AHI Carrier, a company supplying air-conditioning
and heating products.
“When considering air conditioning in a mine, let’s only talk
about temperature and humidity to keep the discussion about
cooling. Although there are many parallels, air conditioning in
a mining context is not the same as air conditioning a building.
For starters, the delivery method is vastly different given the
sheer magnitude of cooling required. Open sprays would be
employed instead of cooling coils. A building HVAC designer
24
African Mining April 2020
There are several aspects to consider when it comes to
maintaining air quality in a mining context. These include
factors like temperature, humidity, dust, fumes and other
harmful gases (like methane). Coupled with any of these factors,
airflow will of course be a critical factor.
Piping should be sized and installed in
accordance with rules of good practice.
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