Sep 14, 2011The Dendrobium coal mine, located in New South Wales, has completed testing of active RFID tags to provide location data from deep inside its 1-kilometer-long tunnel, and to display that information on screens at the mine's entrance. The solution—designed and architected by Kobus du Plessis, CSC Australia's location-awareness solutions principal consultant—employs 433 MHz active tags and readers provided by Becker Mining Systems, and is designed to provide traffic management within the dark, narrow corridors of underground mines. Specifically, the system provides users with data indicating the number of workers and equipment items located within the mine, as well as the direction in which they are traveling, before new personnel or machinery enter the tunnels.
In addition, the solution enables management to track a vehicle's health and efficiency, and to adjust them accordingly, if necessary. For example, if a truck enters and returns from the tunnels numerous times over the course of several months, gradually losing turnaround time, productivity may begin to drop. Thus, the technology is intended to improve productivity at mine sites, while also increasing driver safety. Since the trial is now complete, the solution is no longer in use, and awaits capital approval from the mine company's management.
Dendrobium, through its parent company, BHP Billiton, has declined to comment regarding the installation. Becker Mining Systems, however, reports that the technology typically results in fewer traffic errors that could lead to near-misses or collisions.
CSC Australia's RFID mining solution spans a decade, covering multiple applications. Since 2003, the technology has been tested and deployed at several Australian mines, not only for tracking personnel, vehicles and equipment within mine shafts, but also for monitoring warehouse employees, machinery and tools aboveground.
Dendrobium, which began its long-wall operations (in which a lengthy wall of coal is mined in a single slice) in 2005, has an annual production capacity of approximately five million tons of coal. About two years ago, Becker Mining Systems installed the solution designed by CSC using Becker's 433 MHz active RFID tags and readers. The tags can be attached to miners' headlamps, as well as to vehicles, transmitting a unique ID number every half-second, says Phil Jones, Becker Mining Systems' general manager. Becker deployed a reader at the entrance to the mine's production area, another at the tunnel entrance and a third halfway into the mine. The company also installed a single LCD screen at the tunnel entrance, to indicate which personnel are inside the tunnel at any given time.
Du Plessis began working on RFID solutions for the mining industry in 2003, at BHP Billiton's Mitsubishi Alliance (BMA) Norwich Park coal mine, using EPC Gen 2 passive ultrahigh-frequency (UHF) RFID tags, which he designed and then provided to external vendors for installation. His CSC system includes the passive tags embedded in employees' hardhats, a printable smart label attached to each order's paperwork, and a tag affixed to every piece of equipment stored within the warehouse. As an employee, with a unique ID number on his or her hardhat tag, walks through portals while entering and exiting the warehouse, the system captures that ID and integrates with the company's SAP system, in order to link to the worker's name. At the same time, an EPC Gen 2 passive tag is attached to that individual's order paperwork, and the tag's ID is used to link the order with that particular employee. As the items leave the warehouse, the system again determines that the order has been fulfilled, and maintains a record of which employee completed the work. If necessary, additional parts can be ordered to replace those removed.
Since the passive RFID warehouse solution was developed, Du Plessis has focused his efforts on developing an active tracking system within the tunnels, to reduce the risk of collisions. The dark, narrow tunnels often have twists and turns that a driver must negotiate, and the risk of colliding with another heavy piece of equipment, or another person, is a concern. The Cannington silver mine, located in Brisbane, adopted CSC's solution (also installed by Becker) in 2007, reporting no collisions once the technology was installed throughout the 3.7-mile length of its mine tunnels. However, Du Plessis reports, the system has since fallen out of use, due to a lack of maintenance of its hardware.
According to Du Plessis, CSC Australia's solution can also be utilized in conjunction with leaky feeder pipes (coaxial cables that emit and receive RF signals through gaps in their outer shielding) running the length of a mine's tunnels. By using leaky feeder cables, the system is able to detect where a tag transmission was received, through small gaps in the cables' shielding, and thus determine a tag's location to within approximately 2 meters (6.6 feet).
To date, Becker Mining Systems has installed its 433 MHz tags and readers at about 15 mines in Africa.
