Determination of mixing characterisitics in leaching tanks using radiotracer techniques

Abstract

The mixing characteristics in two gold leaching tanks each of volume 1.4 x 103 m3 were investigated with a pulse injection of 7.4 x 1010 Bq aqueous solution of 131I into the feed of the tanks to determine the flow model and mixing efficiency of the system. The flow patterns in the tanks connected in series were identical with the experimental residence time distribution (RTD) curves generated by TANKSFIT computer software. A two compartment mixing model for the flow pattern, with an effective volume and a dead region was found to provide the best characteristics for the tanks. The model generated effective volumes of 64.2 % and 92.8 % res-pectively in both tanks as against experimental effective volumes of 64.5 % and 91.7 % respectively. The RTD method can be applied to determine process anomalies in mixing tanks, chemical reactors and heat exchangers.

Journal of Applied Science and Technology Vol. 13 (1 & 2) 2008: pp. 44-47