Exergetic Efficiency of Coal Gasification Using High-Temperature Mixtures of O2/N2 and O2/CO2

A search for ways to improve the efficiency of energy technologies requires the selection of appropriate efficiency criteria and a study of the influence of different factors on them. This paper focuses on coal gasification, including hard coals and brown coals, in air and steam media, considering different efficiency criteria for gasification processes: cold gas efficiency, energy efficiency that takes into account the heat of the gasification agent, and exergy efficiency that considers the chemical, thermal, and mechanical energy of reactants and products. The dependence of these efficiency criteria on stoichiometric ratios and air temperature is demonstrated, and the applicability of these criteria in power plant analysis is discussed.