Xstrata Mines RFID’s Benefits

Nov 04, 2008International mining group Xstrata has completed its rollout of a Wi-Fi-based active RFID system to track staff, improve safety and raise productivity at its Beltana Coal Mine in New South Wales, Australia. The company's coal division has installed 200 active RFID tags, supplied by AeroScout, into the battery packs of cap lamps worn by the miners.

Luke Dyer, project coordinator of Xstrata's coal division, says the company decided to investigate a personnel- and equipment-tracking system at the same time that it purchased new cap lamps, in order to improve mine safety and productivity.

"A tracking system provides invaluable information to mining officials in the event of an emergency, and allows them to plan and react in a more focused and timely manner," Dyer says. Knowing the exact location of personnel during an emergency, he adds, allows mine officials to better manage the situation.

The system, according to Dyer, "could also allow some automation of certain safety systems that are currently largely based on manual auditing, such as whether there are enough CABA [compressed-air breathing apparatus] pods in a particular underground section."

In addition to providing safety benefits, radio frequency identification is also expected to improve productivity, because the technology reduces the time that would otherwise be spent looking for personnel. What's more, if the tags are attached to equipment and tools, Xstrata could track them in real time, managing such items more effectively and thus increasing their utilization in the mine.

Xstrata's coal division approached Mine Site Technologies (MST), a global mining communications company, because its hardware was already established in the underground coal industry, in New South Wales and overseas. MST's business development manager, Denis Kent, says the company had been working with Xstrata to track staff members at mines in Queensland and New South Wales using active ultrahigh-frequency (UHF) tags. When Xstrata wanted to track workers at its Beltana Coal Mine as well, MST proposed a system employing the latest Wi-Fi based active tags.

"Like any tagging system," Kent says, "it is based on readers detecting tags. Our skill has been to take these basic elements and turn it into a system that is integrated into the mine's communication back bone and IT system, and can be deployed and operated underground in a reliable manner."

According to Kent, all miners wear integrated communications cap lamps while underground, and MST has integrated AeroScout active RFID tags, based on 802.11b Wi-Fi protocols, into the lamps' battery packs.

Instead of traditional readers, the system utilizes Wi-Fi access points designed specifically for underground mines, known as wireless network swatches. The wireless access points pick up the Wi-Fi tag transmissions, Kent explains.

"The access points—or, as we call them, our ImPact Wireless Network Switches (WNS)—are placed at strategic places at mine entries and underground to monitor the tag movements within zones," he says. "The tracking information is displayed over a mine plan, or map, showing where people are. This uses AeroScout's advanced MobileView tracking software, which we have customized for mine applications."

The real-time location of every miner can then be viewed on a map, enabling Xstrata to locate specific employees when needed for improved productivity and efficiency, and to gather miners quickly in the event of an emergency.

The next stage will be to install the active tags on 50 vehicles to track them throughout the mine, providing Xstrata Coal with accurate real-time data regarding vehicle location, and allowing it to manage the fleet more effectively, as well as streamline vehicle access to the mine. The tags could also be adapted to provide proximity detection around moving machines.

"Mobile equipment moving around in the restricted space of an underground mine needs to be managed well to reduce the risk of collisions between vehicles and people," Kent states. "By using readers and on-board processing units on vehicles, an alert can be given to a driver of someone approaching in their vicinity. Xstrata is a particularly proactive mining company when it comes to safety, so they have supported our research and development efforts to bring the proximity-detection system on line in 2009."

Because the system is based on technology already deployed at other coal and hard rock mines worldwide, rollout was able to be achieved in just two months, after signal surveys were carried out to ensure signal propagation was effective for reliable tag reads. Kent says MST is now working to increase the density of the access points.

"The increased density will allow tracking zones to be smaller," he explains, "but, more importantly, also allow continuous signal coverage on the main travel roads for the introduction of VoIP [voice-over-IP] telephones for mobile, two-way communications in the mine." The system is still in its infancy, Dyer says, though early signs are positive.

"The major challenge now is to introduce the new technology to the people who will get the most use out of it—that is, the miners," he states. "Once acceptance is given by the workforce, I believe the system will be another tool to increase productivity and safety. Assuming the system continues to perform as expected, we will purchase enough external tags so that all equipment and implements can also be tracked."