Determination of mass transfer coefficient in an L-shaped pulsed column with sieve-plate structure: Application of best-fit technique, drop size distribution, and forward mixing model

Abstract

The mass transfer coefficient in extraction columns is extremely affected by the size of the droplets. Among the available models to describe the extraction columns, only the forward mixing model (FMM) has considered the effect of droplets size on the column performance. In this research, the performance of an L-shaped pulsed sieve-plate column (LPSPC) was studied using the FMM. A real-code using the best-fit technique and PSO algorithm was developed for finding the optimal values of the axial dispersion and overall mass transfer coefficients. The effect of the operating parameters including pulsing velocity, continuous and dispersed phase flow rate on the volumetric overall mass transfer coefficient, the axial dispersion coefficients, and the mass transfer driving force was studied for two standard chemical systems. It was found that the LPSPC has an optimal operation at the pulsing velocity of 0.95 cm/s in each of the horizontal and vertical sections. Moreover, the performance of the column is strongly dependent on the ratio of the inlet velocity of the phases. It is worth noting that, the separation efficiency in the vertical section is slightly (on average 5%) higher than in the horizontal section of the column.