Effective Combustion Rate of Anthracite Particles Dispersed in the Granule of Calcined Raw Material

Abstract

For the operation of a fixed-bed-type kiln, in which granules containing anthracite are charged, it is important to control the effective combustion rate.There has been little information on the quantitative treatment of this problem, owing to the presence of many factors affecting the combustion rate, such as diameter and internal surface of granules, mean diameter, internal surface and specific surface of anthracite particles, content of fixed C in anthracite in granules, concentration of reactant gas, coefficient of reactant gas diffusion and combustion temperature. In the scope of the present experiments, thickness of gas film arouhd granules was found to be negligible.Based on the experimental results and dimensional analysis, the effective factor for the combustion rate constant of anthracite particles in a granule was introduced (Eqs. (1) and (2)) as the function of dimensonless terms of factors (Eqs. (9) and (10)).An experimental equation for φ was also shown under given conditions (Eq. (10-a)).