MODELING SOLIDS AND GAS-FLOW THROUGH AN L-VALVE

An experimental program was conducted to study the flow of particulate solids through an L-valve with air as the regulating medium. Two diff erent size solid granules were used in L-valves of diameters 25, 36, a nd 50 mm using two horizontal sections length of 170 and 290 mm. For s uch 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 downc omer and horizontal sections of the L-valve, can be used to predict th e superficial gas velocity in these two sections at any operating cond itions of the L-valve. Correlations are also given from which external aeration and the pressure drop across the L-valve can be predicted fo r any solids flow rate. (C) 1998 Elsevier Science S.A. All rights rese rved.