Page 70 - pd297-Sept21-mag-web

MInInG seRVIces

Air of change sweeps underground sector

fter three decades of predominantly open on cold Arctic conditions as well as around and enables innovation, according to Van der
Apit operations, Australian precious and automation of ventilation and the electrifica- Berg.
base metals operations are increasingly tak- tion of underground fleet because that indus- “Getting rid of diesel contaminants has a
ing the plunge to underground production, try has been quick to adopt that technology.” big upside since EVs aim at removing diesel-
creating a new set of considerations. The electrification and automation of min- based air contaminants, enabling ventilation
Chief among those considerations are ing fleets is a hot topic of discussion in Aus- systems to be optimised by considering strat-
refrigeration and ventilation. Deeper mines, tralian mining as underground miners strive egies like controlled recirculation and recondi-
stricter regulation, awareness of employees, to emulate the major open pit iron ore miners tioning of air,” he said. “One thing EVs present
automation and the electrification of under- in lowering their emissions. The trend should is an opportunity to look at more innovative
ground mining fleets, have led to a shifting of also have positive ramifications for workplace ways of ventilation circuits, including the recir-
the ventilation and refrigeration landscape for safety, but BBE principal engineer Hans Möh- culation of primary air. By removing the diesel
underground miners wanting to ensure the le warned an all-electric fleet would not be a contaminants, it may be possible to recondi-
health and safety of their workforce. panacea to Australian miners’ ventilation and tion as much as 30% of the air underground.
“There are a lot more open pits transition- refrigeration requirements. That may lead to miners being able to defer
“I think a lot of miners believe electrification ventilation or make it smaller.”
is the silver bullet for all their ventilation prob- Möhle said EVs also introduced new chal-
lems,” Möhle said. “We say that even though lenges underground which miners would
it reduces the heat load and removes diesel have to be aware of.
particulate by burning less diesel, there is still “While EVs reduce the fire risk from stored
the issue of dust, strata gasses and clearing diesel underground, inherently to batteries
of blast fumes. and their charging stations, they introduce a
“You can’t just introduce electric equipment new fire risk which is something operators,
maintenance managers and mine designers
have to be conscious of. The heat from charg-
ing stations is a heat load ignored by many to
date,” he said.
Van den Berg urged miners to consider
their ventilation needs long before the need
for action.
“It is something mining companies need
to invest in for the future. A new ventilation
system including intake and exhaust shaft,
primary fans and refrigeration system can
Leon van den Berg cost $90 million for a single deep mine, so
companies need to do their due diligence on
ing towards underground in Australia,” Leon it. The ventilation systems are also big power
van den Berg, managing director of BBE users and strategies to optimise power us-
Consulting told Paydirt. “This leads chal- age and novel technologies need to be in-
lenges around the quality of air, the presence Hans Möhle vested in.
of particulates with larger trucking fleets and “Employees and the general public have
heat. It is a theme which is only going to in- never been more aware of airflow and ven-
crease over time.” and expect to halve your ventilation require- tilation issues than in the face of a global
Van den Berg has been at the head of BBE ments. The fleet that is only one part of the pandemic spread largely through airborne
Consulting for the Australasia region since equation and a mine ventilation system is not transmission.”
2013. Based in Perth, BBE Consulting is part only dependant on the fleet but also on the Australian mines have so far staved off
of the BBE Group which has grown as a bou- mining activity. Mines using EVs will still re- the debilitating shutdowns associated with
tique engineering consulting firm to providing quire ventilation and cooling because of the COVID-19 but the Canadian and South Af-
a full range of engineering services from con- depth, hot rocks and heat from the EVs them- rican mines have been affected. Möhle said
cept design to construction and execution. selves as well as to remove contaminants BBE had been engaged by South African
The BBE Group has offices in Perth, Jo- from other mining activity.” miners to assess how COVID-19 could be
hannesburg and Sudbury, providing clients In 2012, the International Agency for Re- addressed.
with expertise based on operational experi- search on Cancer classified diesel engine ex- “We have been approached to do airflow
ence in the world’s largest mining cultures. haust emissions as carcinogenic to humans, stream modelling (computational fluid dy-
“We are at an advantage because we can leading mining regulators such as the West namic modelling) in South African mines,
call on expertise from regions which pose dif- Australian Department of Mines and Energy because it is a big challenge there, espe-
ferent challenges and knowledge,” van den to limit emissions levels in underground min- cially in the man-riding cages of the deep-
Berg said. “For instance, South Africa has ing scenarios. level mines there,” he said. “We have not
well-developed expertise in deep mining and There appears to be an expectation that been approached by Australian mines yet
refrigeration, while Australia has unique chal- the arrival of EVs will materially reduce the but would certainly look at it.”
lenges around climate, steep rock thermal need for ventilation, instead the focus should
gradients and the remote nature of opera- be for how it will improve the health and safety
tions. In Canada, we have know-how based of underground workers and encourages

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