Image processing for characterization of iron ore pellets using geostatistical instruments

Approximately in the last 20 years, the computational methods have advanced very fast and affected a vast range of discipline. Also, new dimensions in the applications have appeared as parallel to development of computing technology. One of the study methods requiring exhaustive data processing in the earth related science is geostatistics. Iron ore pellets are produced by using magnetite or hematite concentrate together with a binder and water addition. The raw pellets are sintered to produce the sufficiently strong pellets. Some parameters such as type of the binder, addition amount of the binder and sintering conditions affect the quality of the product pellets. The physical quality of the product pellets can be determined by physical pellet testing methods. Physical quality of pellets can be considered as function of sintering conditions. In this study, sintering properties of magnetite pellets produced with bentonite binder are examined by geostatistical image processing method. Polished samples of the pellets were prepared and micro images were taken by a stereomicroscope. The micro images are processed by ISATIS software and converted to digitised images. Models are analysed using geostatistical instruments like kriging and image filtering. The obtained data are used to examine the sintering properties of the pellet matrix. The differences in the pellet matrix (core, inner shell and outer shell) may be used to understand the sintering properties of the pellets. The results may be correlated with the physical quality parameter of the pellets.