Exact hydrodynamic description of pilot plant Oldshue-Rushton contactor: a case study with the introduction of selenium and tellurium into reaction system

Abstract

ABSTRACT In this paper, the hydrodynamic behaviour of the chemical reaction system (selenium, tellurium, and TBP) was interpreted in the Oldshue-Rushton extraction column. The optimum operating parameters for extracting the selenium and tellurium from chloride medium were carried out by using the batch experiments. The feed acidity of 5 molar and solvent phase with 20% (v/v) TBP in kerosene were optimised to examine the hydrodynamic parameters of the mentioned column. The impacts of operating variables such as rotor speed, inlet aqueous phase velocity, and inlet solvent phase velocity on the dispersed phase hold-up, mean drop size, slip velocity, drop size distribution, and extraction rate were evaluated in the column experiments. The experimental drop size distributions in the Oldshue-Rushton column were fitted with the two modified functions containing the normal and log-normal. The stable parameters within the mentioned functions were connected with the operating variables, reactive and physical systems. Among the two distribution functions, the modified log-normal is found to accomplish sufficiently in the fitting of the drop size distribution. The previous models for predicting the dispersed phase hold-up, mean drop size, and slip velocity as a function of operational parameters, column geometry, and physical properties of the mentioned system were compared with the experimental data, which the available models were sensible precision to anticipation the hold-up values, mean drop size, and slip velocity in this extractor. The results of extracting the selenium and tellurium with TBP in the extractor indicated the column feasibility with the proper extraction for tellurium and selenium in the chloride solution.