Decision making in mining operations -inaccurate timely data, accurate tardy data

摘要

Iron ore shipments need to be within tolerance of a target composition, not only in iron, but also silica, alumina and phosphorus. Ships are loaded from stockpiles, built from trainloads from the mine. Mine faces are dug each day to bring the smoothed grade back to target. This decision uses assays of material sampled when the blast holes are drilled. The assays have large errors. Assays at the port are more accurate, but too late for the selection decision. Our system uses feedback from port train assays to adjust blast hole assays for material not yet mined. This has improved the daily selection of mining faces, and thus the quality and value of shipped ore. Further improvement is discussed. The model was developed in close cooperation with users, enabling the computer to do what it is good at, releasing humans to spend more time doing what they are good at.