Abstract
Performance Studies on a liquid-liquid contactor with oscillating multiple baffles are reported. Two three component liquid systems - CCL[4] - HAC - H[2]O and MIBK - HAC - H[2]O - were studied. The mass transfer efficiency of the contactor have been evaluated with respect to the variation of operating conditions, flow ratio and solute concentration in the feed phase. Empirical correlations for the overall mass transfer coefficient have been proposed. Drop size studies based on photographic techniques are reported. Sauter mean drop sizes were obtained from the photographs for a wide range of operating conditions. Using this data and the data for the dispersed phase hold-up, obtained by the manometric method, the interfacial area of the dispersion was calculated for the same operating conditions. Axial mixing properties were investigated for single phase flow using a dye injection technique. Residence time and axial mixing parameters were obtained, and their significance discussed. A correlation for the axial mixing coefficient has been proposed. The Miyauchi and Vermulen type one dimensional diffusion equation for predicting Number of Transfer Units was solved analytically and numerically. The limitation associated with the use of this equation especially with respect to (a) variation of NTU along the column length, and (b) boundary conditions has been discussed. The maximum operating conditions have been investigated for a number of operating conditions, and the effect of solute concentration in the feed phase on maximum operating conditions have been demonstrated. The power consumption characteristics have been investigated and correlation for total mixing power PM (i.e excluding dry power), have been proposed. Due to a proportion of unswept volume, correlations for total mixing power P[M], total mixing power per unit active volume P[va] and total mixing power per unit swept volume P[vs], have been proposed. Mass transfer and power studies are also reported for a smaller contactor with a single oscillating baffle. The experimental results of the two contactors have been compared for scale-up purposes.