We have developed a tool for the prediction of the firing behavior of any coal in a specific boiler that included many aspects such as emissions, performance, and operational issues. The tool has been tested for various coals fired in Israel Electric Corporation (IEC) 550MW opposite-wall and 575MW tangential-fired utility boilers fired. We also developed methods for studying the fouling and slagging behavior and determining the emissivity of the fly ash. In this study we further the development of these methods and applied them to investigate a new bituminous coal in a 50kW test facility and these full-scale coal-fired boilers - Anglo-Mafube bituminous South African (MAF) coal - with the objective to predict its behavior in these boilers. From this study, light can be shed on the behavior of MAF coal in other boilers.