KAGAKU KOGAKU RONBUNSHU, Vol.22, No.4, 898-906, 1996
Analysis of steam flow behavior in packed bed of coal particles
Steam outflow rate and temperature distribution in packed bed of coal particles were measured, measured and compared with results of the numerical analysis in order to determine the steam flow behavior in the coke oven chamber. The moisture controlled and size graded pulverized coal particles are packed in the cylindrical stainless steel vessel with steam flow pipes on both ends. The upper end of the vessel is heated from 293 to 653 K with a constant heating rate of 3 K/min and kept at 653 K. Numerical analysis, including a concept in the evaporation/condensation behavior, is conducted in the axisymmetrical coordinate system. The unsteady heat conduction equation in the solid phase and mass. momentum and energy conservation equations in the gas phase are simultaneously solved. The condensed water in the bed is supposed to be static and as a part of the solid phase under the assumption of local thermal equilibrium. Estimated results on the temperature distribution and the steam outflow rate are quantitatively in good agreement with experimental results and the model performance is verified. Steam flow toward the heated side decreases the heat transfer rate, while steam flow toward the insulated side increases it.
Keywords:CARBONIZATION