Deep Breathing: Ventilation-on-demand system improves Vale mine energy use
Written by Vanessa Chris
Many industries are finding that not only are there marketing benefits
to shrinking their environmental footprint, but cost-saving benefits as
well. And while certain industries are able to make a seamless switch
to green, other industries — such as mining — find it a little more
difficult.
However, when international mining giant Vale first hired Sudbury,
Ont.-based engineering, automation and software development firm
Bestech to help design a ventilation-on-demand system for its Coleman
mine, the original goal wasn’t to save energy; it was merely to find a
way to move air around more efficiently.
Mining ventilation systems are one of the most costly components of the
mining process — both money-wise and production-wise. With the amount
of contaminants and fumes that are created by the mining process,
proper ventilation is required to ensure all of a mine’s people, and
equipment, are able to work. With the mind-boggling number of shafts in
an average mine, a lot of ventilation is required to keep the air
moving.
Traditionally, to ensure a mine was properly ventilated, one had to
over-ventilate. Fans on the surface would push fresh air down, and
auxiliary fans underground were required to push air through the
drifts.
“Because mine circuits are so complex, you’re often looking at between
100 to 200 auxiliary fans running 24/7 at 100-percent capacity,” says
Marc Boudreau, president and CEO of Bestech. “As a result, it’s not
unheard of for ventilation costs alone to range between $3 million and
$6 million annually.”
This type of ventilation system also limits productivity because one
can only mine in areas where you have proper airflow and air quality.
If one wanted to expand activity to another area of the mine that
wasn’t ventilated, they’d have to first reconfigure their ventilation
plan.
Enter ventilation-on-demand
The purpose of a ventilation-on-demand system is to only ventilate
those areas that are in use — thus, drastically reducing energy usage.
While the concept has been around for approximately 25 years, Bestech
was one of the first to establish a system that is using
state-of-the-art technology and robust enough to work in a harsh mining
environment.
The company has been working on ventilation control strategies since
2000, and is currently on its third version of its software — NRG1-ECO.
“Back in 2000, we were focused solely on developing scheduling tools —
turning the fans up and down according to a predetermined schedule,”
Boudreau says. “What we were doing was unique at the time because we
were using web applications — and that was cutting-edge software back
then. We were really pushing the envelope of real-time systems over the
web.”
Through the decade, the software evolved, and in 2009, Bestech started
planning its third version, with a focus on increasing functionality
through even more advanced technology. While Vale was one of the first
companies to help dictate the direction of the new software, it was
just one of Bestech’s many partners in the project. That’s because the
goal of this project was different: it wasn’t to merely reduce a mine’s
ventilation energy usage, but to optimize mining processes, people and
equipment and increase productivity.
“At the end of the day, production rules,” Boudreau says. “Mining
operating costs range from $200 to $400 million per year, so what is $1
to $3 million in energy savings? It’s a start, and in reality provides
a two to three-year ROI. The bigger benefit is increasing overall
productivity, which can yield tens of millions in increased revenues.”
The advanced nature of the product, as well as the potential
environmental angle, qualified the project for federal R&D dollars
and simultaneously captured the attention of other government research
groups and non-profit foundations. To qualify for funding for one of
these foundations, Sustainable Development Technology Canada (SDTC),
Bestech was required to establish an industry consortium.
The consortium, which continues to provide support to Bestech, consists
of research partners (such as MIRARCO, which is a research company
affiliated with Laurentian University), funding partners (such as the
Centre for Excellence in Mining Innovation as well as clients like Vale
and Xstrata) and technology partners (such as RFID vendors, which help
ensure the program is easily integrated). It proves to be a valuable
resource for the company, offering plenty of sound advice, ideas and
suggestions (along with funding) to make sure the project is something
that can truly move the mining industry forward.
The future of mining
One of the ways NRG1-ECO exceeds previous versions of the software is
through its ventilation-on-demand accuracy and open technology. For
example, thanks to the use of RFID tags — which are placed on each
employee and each piece of equipment in the mine — the program can
gather enough information to know when people or equipment are in a
specific mining zone, and alter the ventilation accordingly.
This has proven to be a useful feature in reducing blast gas clearing
time — an area that Bestech is continually developing. When removing
ore, mines must undergo a repetitive daily process: first miners head
into an area to drill, then they blast, then recondition the area, and
then they send machines in to pick up the ore. The problem is that,
after a blast, the air becomes contaminated and there’s a time lapse of
lost productivity — ranging from between 15 and 60 minutes — as miners
wait to enter the zone to recondition the area and collect the ore.
Through the use of RFID tags and sensors measuring air quality, Bestech
is working on reducing that amount of downtime by developing ways to
more efficiently remove the contaminated air out of the mine, so miners
can get through the necessary corridors and collect the ore quicker.
The company has also gone to great lengths to ensure its technology is
open, allowing it to accommodate the varying needs of different mines
current networks and communication protocols, both today and down the
road. This design has been a definite benefit for Vale and other
companies who have already signed up for their installation.
“Every mine is different — each one has unique requirements, operates
in a slightly different environment and requires a customized, tailored
installation for their respective operation. Bestech tries to
understand what their client requires, and utilize the right technique
to get them what they want,” says Cheryl Allen, chief ventilation
engineer for Vale.
This flexibility has allowed Vale to roll the technology out in stages
— it currently has a portion of its Coleman mine “tagged” (with RFID
tags). While the system is functional, and the company has already
proven the potential for approximately 30 to 40-percent energy savings,
the goal is to expand the system to other parts of the facility. There
are many infrastructure changes the company may wish to change some day
as well, such as implementing a wireless communication infrastructure,
and they’re certain that if and when those changes are made, Bestech
will be able to tweak the existing framework accordingly.
While the software is capable of working with other technology that
might not be implemented quite yet, it’s also capable of working with
less-advanced technology that already exists. This is a huge benefit
for companies that don’t want to overhaul their entire communications
infrastructure.
One example is if they have copper wire-based communications systems
(or “leaky-feeder systems”), rather than more advanced fibre-optic
systems. Understandably, it takes a lot of communication infrastructure
to transmit data from 8,000 feet below ground to computer systems on
the surface. While many newer mines are currently equipped with
fibre-optic systems — allowing them to transport more information at a
faster pace — most older mines rely on copper technology. Replacing
this technology can prove extremely costly, which is why it was
important to ensure that NRG1-ECO could accommodate the older system
and deliver the same results.
Accommodating varying brands of PLCs was also a necessity. Each
Intelligent Zone Controller — the device which control a mine’s fans —
is equipped with a PLC. “Every client uses a different PLC
manufacturer,” Boudreau says. “We wanted to make it so that it doesn’t
matter what PLC manufacturer you use.”
Buying in
While advanced technology is definitely a huge component of the
NRG1-ECO system, it’s probably the easiest piece of the puzzle to
implement. The most difficult part of the process so far has been
winning that buy-in from company employees and, to some extent, the
industry as a whole.
“Not everyone is okay to have an RFID tag attached to them. That’s a
social obstacle we have to deal with,” Boudreau says. “If you don’t get
buy-in from people, your system won’t work.”
So far, the company has been trying to overcome this through education
and awareness — by sitting people down, highlighting the safety
benefits and explaining the details of the system. In reality, the
monitoring process can’t determine if someone is taking a
longer-than-average break. It monitors the mine by zones, which can be
roughly a kilometre long, and can only detect whether an employee is in
the zone or not. It can’t determine what that person is doing — or
whether they’re even moving — thus avoiding a “Big Brother” type of
monitoring.
“I don’t think it will ever go in that direction,” Boudreau says. “The
cost of putting in infrastructure to follow employees and equipment is
expensive.”
Bestech knows its technology is capable of increasing mining
productivity in several other ways, hence, it continues to research and
develop its NRG1-ECO platform and inventory of mine efficiency and
productivity products so that it can reduce the high cost associated
with overhauling existing legacy systems, which have and always will be
an obstacle in moving the entire industry forward.
That being said, the new technology is gradually gaining interest in
the mining community. The company currently has eight new projects at
various stages, including Goldcorp and mining companies in the
Northwest Territories and Manitoba. It has also received interest from
foreign mining companies in Peru and Mexico.
“This technology will definitely bring significant changes to the
future of mine design and the notion of moving air around,” says Glenn
Lyle, R&D program director for the Centre for Excellence and Mining
Innovation, a consortium member.
Vanessa Chris is a freelance writer based in Toronto.
Enter ventilation-on-demand
The future of mining
