Document Type : Full article


1 School of Chemical Engineering, Faculty of Engineering, University of Tehran, Tehran, Iran

2 Materials and Nuclear Fuel Research School, Nuclear Science and Technology Research Institute, Tehran, Iran


The droplet size distribution in the column is usually represented as the average volume to surface area, known as the Sauter mean drop diameter. It is a key variable in the extraction column design. A study of the drop size distribution and Sauter-mean drop diameter for a liquid-liquid extraction column has been presented for a range of operating conditions and three different liquid-liquid systems. The effects of rotor speed, and dispersed and continuous phase velocities on drop size are investigated. Drop size distribution are appropriately described using the normal and log-normal probability density functions. The mathematical approach is used to determine the constant parameters in these functions and to provide the fit of the experimental data with them. and empirical expressions are derived to predict the parameters of the distribution curve as a function of operating variables, and physical properties of the systems. Good agreement between the prediction and experiments was achieved for all investigated operating conditions. An empirical correlation is also proposed to predict the Sauter-mean drop diameter with mean deviation of 9.8%.


Main Subjects

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