Modeling and analysis for fluidized dense phase conveying including particle size distribution

Pressure drop in fluidized dense phase pneumatic conveying involves frictional interactions among gas, particle and pipe wall. There have been numerous correlations proposed by different researchers for predicting the pressure drop in fluidized dense phase conveying. In this paper steady state flow equations have been written for different phases and these equations are solved by assuming certain factors for different conveying materials. For writing the flow equations, a single gas phase and certain number of solids phases (which are chosen based on the particle size distribution of the conveying material) have been considered. Experimental data have been used as initial conditions at the exit of the pipeline in order to solve for the value of the flow parameters at the inlet of the pipeline. Experimental data have also been used to find the maximum possible conveying distance or maximum possible conveying pipeline diameter by imposing certain limiting conditions of conveying. Scaling equations for the solids mass flow rate and the air mass flow rate have been used to predict the pressure drop for different pipeline diameters and pipeline lengths.

Conveying materials are of non-uniform particle sizes, but have a size distribution. Conveying material is a mixture of solids phases of different mean particle diameters. Each solids phase introduces frictional force with pipe wall during the conveying process, which contributes to the pressure drop. Other forces involved are frictional forces due to gas and pressure forces.Figure optionsDownload as PowerPoint slideHighlights
► Pressure drop is predicted considering number of solids phases.
► Solids friction coefficient is correlated with a material property parameter.
► The model is simulated under pipeline length and diameter scale-up conditions.