Gasification of coal was carried out in a fluidized bed reactor(0.1m-I.D.×1.6m-high) over a temperature range of 1023 to 1173 K at atmospheric pressure. To understand the overall gasification reaction, the kinetic studies of the steam-char and oxygen-char reaction were performed in a thermobalance reactor, and the pyrolysis of coal in a fluidized bed reactor also was carried out. In the kinetic studies of coal char, the reaction rate equations could be expressed as
dX/dt = kPⁿ_{O2 or H2O}exp(-E/RT)(1-X)^2/3
The activation energies of steam-char and oxygen-char reactions were found to be 27 and 40 kcal/mol respectively in a chemical reaction control region. For the pyrolysis reaction in a fluidized bed reactor, all gas components yields increased with increasing the reaction temperature and fluidizing gas velocity. The product gases of the gasification reaction in a fluidized bed reactor were composed of H₂(30-40%), CO(23-28%), CO₂(27-35%) and CH₄(6-9%), and the heating value of the product gas was about 2000-3750kJ/m³ at employed experimental conditions. As reaction temperature and steam/coal ratio increased, while as the air/coal ratio decreased, the heating value of the product gas increased.