Release of potassium and sodium species during combustion of various rank coals, biomass, sludge and peats

In this study, release characteristics of potassium and sodium species during combustion of various rank coal, biomass and sludge and peats with different physicochemical properties were examined. Most types of K and Na contained in the fuel were ionized and released, and existed as the KCl and NaCl form in the fuel. An increase in the chloride content in the fuel resulted in a decrease in the emission of KCl, and an increase in the emission of NaCl. In contrast, the KCl release increased and NaCl release decreased with increasing the combustion temperature.