Pressure-Drop Correlation for Designing Vertical Dilute-Phase Gas-Solids Lift-Lines for Materials Used in Coal Conversion Processes

摘要

Many correlations are available in the literature to estimate pressure drop in vertical, dilute-phase, gas-solids lift-lines. However, most of these correlations are developed from data obtained in low-pressure systems and with materials other than coal. Therefore, the applicability of such correlations for the design of high-pressure coal transport systems, required in several coal conversion processes, should be evaluated. The Institute of Gas Technology is reviewing the available methods and correlations for estimating pressure drop in vertical, dilute-phase, gas-solids transport of materials, such as coal and char used in coal conversion processes. The published data used to evaluate these correlations cover a wide range of operating conditions: particle diameters, 160-19,050 micrometers; particle densities, 59-245 lb/cu ft; pipe diameters, 0.18-6 inches; operating pressures, 14.7-680 psia; and transport gas densities, 0.005-3.4 lb/cu ft. Evaluation of the various published correlations for estimating pressure drop in vertical, dilute-phase, gas-solids transport lines, shows that on an overall basis a modified Konno and Saito's correlation is the best and is, therefore, recommended for designing gas-solids transport lines for coal and related materials at low as well as high pressures. It is not the best correlation possible, but a better understanding of the mechanism of pressure drops in lift lines and more experimental data on coal are needed to develop such a correlation. (ERA citation 03:051866)