Design of sieve plate spargers for bubble columns: role of weeping

Abstract

Weeping through perforated plates occurs when the pressure drop of the gas/vapor passing through it is insufficient to support the liquid. The critical weep velocities (V_{O, crit}) were measured for the plates having hole diameter range of 1 to 6mm. The thickness to hole diameter ratio (t/d_O ) and the pitch to hole diameter ratio (P/d_O) were varied in the range of 1 to 6 and 3.9 to 25.8, respectively. It was found that the V_{O, crit}, crit is a strong function of plate parameters and the clear liquid height. A mathematical model for "No weep" condition was developed under the following two extreme conditions: (i) holes are partially open, (ii) holes are completely active. The results obtained from the experimentation and the mathematical correlation were put into a coherent form. The weeping criterion in terms of the Froude number was correlated with the plate parameters and the clear liquid height.