PRESSURE EFFECTS ON GAS-LIQUID INTERFACIAL-AREAS IN COCURRENT TRICKLE-FLOW REACTORS

The influence of pressure on gas-liquid interfacial area in cocurrent trickle flow fixed bed reactors is investigated. Interfacial areas have been determined from diethanolamine carbamation of aqueous more or less viscous solutions of ethylene glycol for pressures up to 3.1 MPa in a 0.395m-height and 23mm-ID column packed with hydrophilized polypropylene extrudates, porous carbon cylinders or glass beads. At gas superficial velocities less than 0.02m/s, interfacial areas are found to be pressure-independent, allowing for an acceptable estimation at atmospheric pressure. However, above this limit, even if the flow regime is still trickling, gas-liquid interfacial area increases with pressure for constant gas and liquid velocities. These findings are tentatively explained by the influence of gas inertia on break-up of bubbles trapped in the liquid films trickling over the particles.