CVRD Inco Tracks Ore in Mine and Mill

Once the tags are placed into the ore, a front-end loader scoops the muck into buckets, which dump it—along with the RFID tags—into a vertical shaft that leads to a crusher. The chunks of ore come out of the crusher less than 6 inches in size, then put into passes (large areas where the ore is held until it can be brought up to the surface). In tests, the tags have survived the crushing process.

At the surface, the crushed ore is funneled onto a V-shaped conveyor belt, which moves at a rate of 300 feet per minute, carrying the ore to be dumped into train cars. Ship2Save has outfitted the conveyor belt with eight antennas and an XR440 RFID reader from Motorola. The interrogator is housed in a National Electrical Manufacturers Association-certified enclosure to protect it from dust, weather and other elements. The tag is read as the ore containing it passes under the antennas. The tag data is then fed into Ship2Save's tracking software, which passes the information on to CVRD Inco's back-end system.

"The tag may be floating on top or buried far below," says Eddie Ng, Ship2Save's project manager for CVRD Inco, "but our testing has revealed that the tag can be read deep into the ore." CVRD Inco employees can view the data anytime, by accessing real-time reports in Ship2Save's tracking software.

What makes this RFID tracking system unique is that the tags are not physically attached to anything. Rather, they are mixed among the rock being tracked. What's more, not only are the tags mixed among the ore from a specific blast site, the tags and ore from several blast sites are mixed together upon being moved into the passes.

To calculate yields that include grade values so the mining company can determine the appropriate chemical mixes, CVRD Inco uses modeling techniques. Now, all the collected tag data—from which each tag read can be associated back to a specific blast site within the mine—will be entered into the company's modeling system, which should greatly improve the company's insight into what exactly is being extracted from the mine, and when. That information will then be shared with the mill, so that the appropriate chemical mixes can be ready when the ore arrives.

CVRD Inco expects to run the RFID trial at its Stobie mine for the next 90 to 100 days. When this is complete—and if results are successful—the mining company hopes to expand the RFID system. "Once this is working well, we'll go into the next phase," Palkovits says. "We want to put the tags into holes in solid ground, and then set off blasts in proximity to these holes so we can track the ore from the blast site." In addition, the firm intends to use RFID to track the railcars moving the ore to the mills. "We currently move about 16,000 railcars a month, and right now we track that with pencil and paper."

Earlier this year, CVRD Inco began rolling out a Wi-Fi-based RFID asset-tracking system from Ekahau. Currently in use at its Stobie and North mines (the latter is also in Sudbury), the system is utilized to track how long it takes a truck driver to retrieve ore and transport it to its deposition site—a metric previously tracked using pen and paper (see CVRD Inco Mines Turns to Ekahau to Track Assets, Productivity).