7TH EUROPEAN COKE AND IRONMAKING CONGRESS - ECIC 2016

The gasification of metallurgical cokes with CO2 and H2O on their porosity and macro-strength were investigated in the current study. Cokes were reacted with CO2 or H2O in the temperature range of 1100 to 1500oC. During the reaction, the compositional change of product gases were measured by Quadruple Mass Spectrometry (QMS) for evaluating the gasification rate. Image analysis was carried out to measure the porosity according to the distance from coke surface. The porosity at the surface of coke gasified with CO2 indicated low values due to its low reactivity, which resulted in the intraparticle reaction to diffuse into the pores at low temperatures while the coke gasified with H2O showed the tendency to react the coke at the surface. This difference in the reaction behavior can be explained by Thiele modulus. Furthermore, fine powder formation and tensile strength were measured to evaluate macro strength of cokes. According to the results, the different reaction mode caused obvious difference in the tendency of macro strength of the cokes of the same reaction degree. Tensile strength of cokes was strongly affected by their porosity distribution.