The melting behaviour of the metallized, porous wustite pellets immers
ed in liquid slag, as well as the influences of the metallization rati
o, pre-heating temperature of the pellet and slag temperature were exa
mined in this work by means of an X-ray imaging system. The internal s
tructure of the pellets after having been immersed in slag was checked
by optical microscope and EPMA. The adoption of digital image process
ing improved the image analysis dramatically and, as a result, some im
portant phenomena, such as solid slag shell forming and melting, slag
penetration, wustite component dissolution as well as the influence of
experimental conditions, were quantified.