Modelling of the distribution of trace elements in coal

Abstract A theoretical model of the distribution of trace elements in coal based on knowledge of the weight distribution of the organic and inorganic components of coal is presented. The model uses analysed elemental concentrations in coal or coal ash as a function of the ash content of coal to calculate elemental concentrations in the organic and inorganic components. From these values, elemental concentrations in the raw coal can be predicted. In its simplest form, the model considers that coal is composed of two components (organic and inorganic) and that elements are homogeneously distributed in each component. This assumption was used to verify the model and to calculate elemental concentrations in coals of Brazilian and American origin. Agreement between calculated and measured concentrations in the raw coal was within the experimental error of analytical techniques. However, some elements that showed high concentration in the mineral matter could not be modelled on the basis of this assumption. The possibility of calculating elemental concentrations in the organic and inorganic matter of coal allows for a new, quantitative, approach to the characterization of the distribution of trace elements in coals.