A new model for estimating the maximum fluidity (MF) of blended coal was developed. MF is the common logarithm of maximum fluidity with the Gieseler plastometer. This model is characterized by the viscous behavior of a suspension. In the model, the heated coal during carbonization was regarded as a suspension composed of melted coal, non melted coal, and the solidified coke. The viscosity of the suspension (eta) was evaluated by Mori and Ototake's equation, which included the viscosity of the solvent (eta(L)) and the volume fractions of solid (S). The volume fraction of solid at the MF temperature was assumed as the total inert value of the coal. The temperature dependence of eta(L) was determined by Andrade's equation, The viscosity of the suspension of blended coal were calculated from the values of each single coal. The relation between fluidity and viscosity was obtained by Morotomi et al. using the standard substance of polybutene. The calculated fluidity of two component coal with a small overlap in the melting temperature range agreed well with the measured value. Good agreement with measured values supported the validity of this model.
