Ongoing research into an industrial prototype 3D imaging and analysis system is presented for non-contact measurement of the size of iron ore green pellets on the conveyor belt. The imaging hardware has been installed at a pellet production plant and captures 3D surface data of pellets on the conveyor belt. Segmentation methods based on mathematical morphology are applied to the 3D surface data to identify individual pellets. Pellet sizing based on the segmented 3D surface data has been performed and demonstrates a correlation with pellet sieve size.