Abstract
The oscillating baffle column presently described was invented by Dr.W.J.Thomas. It is a differentially operating continuous counter-current extractor. The experimental work is concerned with establishing the efficiency of the extractor under different conditions of operation up to the flooding point. Oscillating speeds and liquid flow rates were varied while other parameters were maintained constant. A direct comparison with the efficiency of operation of a Rotating Disc Contactor was made by carrying out the identical experiments in each case. The general differential equations for the extract and raf-finate phases in a differential contactor model have been derived by several methods. The relationship between the sign of each term in the differential equation and the direction of phase flow has been considered. The overall mass transfer coefficient in the extract phase, ka, has been measured along the column. It was found that a reversal in the trend in ka occurs depending on the speed of oscillation. At low oscillating speed ka is larger at the bottom of the column than the top and at high oscillating speeds the reverse is true. Three methods of calculating the longitudinal mixing coefficient from experimental data have been employed. The method using integration by parts is considered to be the most accurate and reliable. A dye injection technique was used to experimentally determine the C curve for different operating conditions for the Oscillating Baffle and the Rotating Disc Columns. A gamma function was used to relate the C curve to the variance and the longitudinal dispersion coefficient.