INFLUENCE OF MASS-TRANSFER DIRECTION ON THE OPERATION OF A PULSED SIEVE-PLATE PILOT COLUMN

Experimental work has been carried out in order to determine the influence of mass transfer direction on the operation of a pilot pulsed sieve-plate column. The liquid system involved was the water-acetone-toluene, as recommended by the E.F.C.E. Experimental results (hold-up, drop size distributions) have been compared with the predictions of a drop population balance model, which is based on transport, breakage and coalescence laws. It is assumed that transport is weakly sensitive to mass transfer and mass transfer direction. Additional experiments have provided the laws for breakage, exhibiting the influence of mass transfer. Coalescence has been assumed to be negligible with C --> D mass transfer direction, and a collision model has been used for D --> C mass transfer direction. The resulting drop population model predictions are in fairly good agreement with the experimental data. From a practical point of view, the efficiency in the case of D --> C mass transfer direction revealed itself to be higher than in the opposite direction, in spite of a lower interfacial area.