Particle Size Estimation from Pressure Drops of a Pneumatic Conveying Pipe Line

Abstract

Size measurement of solid particles has been generally performed for a test sample. In such a conventional measurement, however, it is time-consumable and not easy to get test samples from a process line. A method of particle size estimation from pressure drops of a pneumatic conveying pipe line is herein discussed for the flow of Newton's region. According to the previous report'), pressure drops of a pneumatic conveying pipe line have been able to be calculated theoretically using empirical values of λs and vt, i.e. friction factor of solid flow through a pipe and mean settling velocity of solid particles respectively. In this paper, λs and vt are obtained from the relations between solid-gas mixture ratio and pressure drops of an accelerating and a constant velocity sections, where the accelerating section has to start at the position of ν=0 such as the feed point of solid particles. Then the mean particle size equivalent to a sphere is calculated from νt, and shows good agreement with experimental results.