Ash composition of main Albanian coals

Coal ashes from seventeen mines in Albania were systematically analyzed to investigate ash yield and the percentages of various oxides including SiO2, Al2O3, Fe2O3, CaO, MgO, K2O, Na2O, TiO2, P2O5, MnO, and NiO. The research focused on defining the contribution of these macro-components to ash contents, their classification into acidic, amphoteric, and basic oxides, as well as examining factors such as coordination number and fluxing components. Significant correlations emerged when analyzing the percentages in mole or ion percent, as opposed to weight percent. The study found that a decrease in basic oxides was correlated with an increase in acidic oxides, highlighting the variabilities in ash properties based on composition. This paper utilized ISO 1171 to determine the weight percentages of ash and proposed a theoretical framework for understanding the chemical relationships among ash species through empirical equations. The findings provide valuable insights into the chemical properties of ash from Albanian coal mines, contributing to the field of coal chemistry and resource management.