Maximum solids discharge rates from hoppers

A theoretical model based on bulk solids handling fundamentals has been developed for estimating the discharge rate of solids from mass flow and funnel flow hoppers. The model takes into account the bulk solid's unconfined yield strength, internal friction, compressibility, wall friction, and permeability. Permeability and compressibility in par-ticular are important because these properties allow prediction of the adverse pressure gradient that develops when fine powders are discharged, which result in gas flowing counter to the solids. Calculated and experimental solids discharge rates from conical hoppers are compared.(c) 2023 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.