7TH EUROPEAN COKE AND IRONMAKING CONGRESS - ECIC 2016

We performed micro-CT imaging and analysis on coke CSR lumps, before, during and after reaction under conditions aimed at replicating the standard CSR test. The aim is to develop a stronger mechanistic understanding of the reactivity of cokes made from different coals, by examining the change in coke microstructure as the high-temperature reaction with CO2 progresses. Individual coke lumps were imaged at the Australian Synchrotron, then reacted with CO2 for 30 minutes, imaged again, and the process repeated until a full 120 minutes of reaction have occurred. The resulting 3D images of coke microstructure show the effect of transport control versus reaction control, as well as the selective reaction of different components of the samples. Results have been obtained for cokes produced from 5 different coals, and the reaction was carried out at two different temperatures (1100°C and 900°C). Micro-CT analysis involves the determination of the size distribution of pores and pore walls, identification of individual IMDC components and finite element analysis to determine measures of strength and gas diffusivity. In this case, we examine how these features of the microstructure change as the CSR reaction progresses, giving us the ability to determine the key elements of the structure that affect its strength as the reaction progresses.