Continuous phase axial mixing in rotary disk contactors

Abstract

This paper presents a review of important investigations on axial mixing in the continuous phase in rotary disk contactors (RDC) and analyses the various literature data in terms of the flow number (D_R N/u_e) and a geometry factor G_f. A new model equation has been developed to represent continuous phase axial mixing in the RDC taking into account the factors affecting the recirculation flow within the compartment and the main flow through the compartment in terms of disk-Reynolds number and modified tube-Reynolds number respectively. A satisfactory expression for G_f has been obtained on the basis of the present proposed model and analysis of data of available literature and those of the present work, covering laboratory and industrial size columns of 10 different investigators varying from 3.5 cm to 218 cm dia involving 19 different column geometries. The following forms of generalized correlation for continuous phase axial mixing in RDC have been suggested. (a) E_c/u_cZ_c=0.5 + 0.028(D_RN/u_c) [D_s-0.5 D_r/D_r] (b) E_c/u_cZ_c = 0.5 + 0.028 [(Re)_R/(Re_T)] (D_s/D_R) - 0.5 (D_r/D_R)]