Arsenic in polish coals: Content, mode of occurrence, and distribution during coal combustion process

The research presented in the paper allowed the determination of the content and mode of arsenic occurrence in Polish commercial coal. The selective leaching method showed that in the case of the examined samples, As in coal occurred mostly with mineral matter (mainly with carbonates, sulphates, and disulphides). In addition, a study of As distribution in the combustion process of the coals was conducted at temperatures of 800 °C, 1000 °C, and 1200 °C. The amount of As that, during combustion, passed to gas was affected by the parameters of the combustion process (temperature and combustion rate) and chemical composition of the coals. Moreover, statistical analysis showed that the amount of Asgas in the flue gas is significantly influenced by the presence of this toxic element in coal mainly in association with disulphides (pyrite), carbonates, and sulphates. In addition to the research methods, statistical analysis based on significance assessment was used. © 2021 Elsevier Ltd