Quantitative XRD analysis of different coal samples to understand their ashing process during the initial stages of combustion

Abstract: Coals in general have very complex chemistry and depending on the intended usage, further challenges are experienced. Such challenges vary from the methods mining and cleaning that should be employed to yield the best quality coal for the specified usage and the final products which are produced from coal use. It is therefore very important to understand the chemistry of raw coal and the ashing properties of such coals and the information from this work can also assist in highlighting the environmental and health aspects that are linked to processing and usage of coal. This work focused on a qualitative studies using XRD to analyze five different coal samples and the chemistry change during the ashing process which takes place during the coal combustion process. An ashing process was conducted on the five samples at 350⁰C, 500⁰C, 750⁰C and 1000⁰C and their results where compared to the composition of the raw coal. The results from this work showed that there are a total of up to 40 major phase-mineral compositions found in the samples analyzed, of which some of them are one phase-mineral composition that appears as different phases/forms in the coal ash