The devolatilization process (referring to the release of gaseous fuel components as the solid fuel is heated) is a key characteristic of the combustion of solid fuels. The volatile gases burn much more rapidly than the remaining char particles and therefore are important for flame ignition and stability and play an important role in the formation of oxides of nitrogen (NOx), a regulated class of pollutants. Moreover, the devolatilization process determines how much char remains to be burned as well as the physical characteristics of the resulting char, with subsequent impacts on the char combustion properties.