Modeling solids and gas flow through an L-valve

Abstract

An experimental program was conducted to study the flow of particulate solids through an L-valve with air as the regulating medium. Two different size solid granules were used in L-valves of diameters 25, 36, and 50 mm using two horizontal sections length of 170 and 290 mm. For such a simple system in which the feed hopper and the discharge end of the valve are at atmospheric pressure, a mathematical model, based on a modified Ergun equation written for the moving bed in both the downcomer and horizontal sections of the L-valve, can be used to predict the superficial gas velocity in these two sections at any operating conditions of the L-valve. Correlations are also given from which external aeration and the pressure drop across the L-valve can be predicted for any solids flow rate.