8th International Congress on Science and Technology of Ironmaking - ICSTI 2018

In recent years we have conducted integrated mechanistic studies to understand the structures controlling coke strength and how these structures form in the plastic layer. These have involved micro CT studies of coke structures and calculation of the response of these structures to stress as well as fractographic studies of fracture surfaces in coke. A number of studies have identified that the boundary between inert maceral derived components (IMDC) and reactive (fusible) derived maceral components (RMDC) in coke can be a source of weakness in the coke. In particular fractographic studies have identified a number of boundary types, depending on how well the IMDC-RMDC are bonded. This study looks at characterising the IMDC-RMDC boundary in 3 dimensions using micro computed tomography (micro-CT). Hand picked coal inerts (1-2mm) were placed in a bed of hand picked vitrinite (<1mm particle size, 5mm diameter bed) in a graphite crucible, sealed and then heated to 1000oC. Micro CT images were collected at the IMBL (imaging and medical beamline) Australian Synchrotron. The non-fused carbon (IMDC) was identified in the image using standard image analysis and an envelope ~200 microns wide drawn around the IMDC. The pore properties of this region were compared with the bulk region of the sample. By sourcing the vitrinite and inertinite from different coals the interactions between macerals of different rank and geological measures could be studied.