Specific surface areas of different raw materials play an important role in ferrous metallurgical processes. Coke (for blast furnace process) and char from non-coking coals (for COREX and FINEX process) are the lifelines for smelting reduction ironmaking processes by providing energy for the process and also supporting the burden load. The reactivity of coke and char depends greatly on the inherent surface properties of the parent raw material. The knowledge about the specific surface area not only provides a forecast for its process behavior, but also indicates the evolution of surface properties under process conditions.
The aim of this work is to develop a standard procedure of evaluating the specific surface area of cokes and chars using the BET (Brunauer-Emmett-Teller) analysis method. A standard sampling method for test specimens have been developed for having enhanced reproducibility and overcoming the heterogeneous nature of the test samples. The pore size distribution has been investigated using the BJH (Barrett-Joyner-Halenda) analysis method. The effects of the treatment of samples under different process conditions have also been investigated. The results provide a better understanding of the variation of surface properties (surface area, pore size etc.) among different samples as well as the effect of treatment under various process conditions.