Pressure Drop in an Equilibrium Region of Vertical Pneumatic Transport of Granular Solids

Abstract

Using polyethylene pallets with a free falling velocity of 5.8m/s, measurements of pressure drop and solids velocity are mode in 41.2, 52.6, 66.8, 78.3 and 100.0 mm I.D. straight P.V.C. vertical pipes of length 24m up to a solids/air ratio of 43, varying air velocity from 9 to 50 m/s. A general correlation for additional pressure drop is derived, taken account of these factors. Pipe friction factors for solids are calculated and shown to be a monotonous increasing function of pipe diameter alone.