Laboratory Combustibility Testing of Solid Fuel

A laboratory furnace having a controlled wall temperature is used to measure the combustibility of coal and other solid fuels. Operation at wall temperatures of 1260–1370°C (2300°–2500° F) permits determination of percent carbon burnout as a function of residence time and excess oxygen under furnace conditions representative of those encountered in large boilers. Operation at decreasing wall temperatures provides information on flame stability under conditions approaching those encountered under low load conditions in operating boilers. Firing rates are generally in the range of 11.7–29.3 KW_t (40–100k BTU/hr) permitting testing of 100–150 kg (200–300 lb.) samples which can reasonably be obtained by core drilling or from small pilot units.