The emission behaviors of fuel-N from coal were studied by pyrolyzing 6 different coals of which the fuel ratio ranged from 0.9 to 6.6, under various heating conditions in He atmosphere. The experiments were made by changing the temperature (573K-1273K), the coal particle diameter (37-4500 μm) and the heating rate (5-1000K/min). As the results: 1) Fuel/N started to be released from coal when the temperature reached about 673-773K, which was about 50-100°C higher than the temperature where the main volatile components like C and H started to be released. 2) Two different emission behaviour of fuel-N from coal were observed below and above 1173K. 3) The conversion of fuel-N increased with decrease in fuel ratio at the same heating temperature. The conversion of fuel-N, the fuel ratio and the temperature were well correlated. 4) There was no influence of coal particle size on the conversion of fuel-N below 1173K. However, when the temperature became higher than 1173K, the conversion of fuel-N tended to decrease with increase in coal particla diameter.
