A new model for residence time distribution of impinging streams reactors using descending-sized stirred tanks in series

A new model was developed for the flow behavior of a counter-current liquid-liquid impinging streams reactor. As a modification of the well-known tanks-in-series model, the new model considers a cascade of descending-sized stirred tanks in series. This assumption is made because a distribution of the residence time exists for different liquid droplets depending on their initial elevation at the entrance to the system. The accuracy of this theoretical RTD model was analyzed through the comparison of the latter with that determined experimentally using the impulse tracer method. The results show that the presented model improves the predictions of the hydrodynamic behavior of impinging streams reactors. A comparison between the sum of the statistical parameter mean residual sum of squares (MRSS) for the new model with a number of previously presented models (the stirred tanks-in-series model, the gamma distribution with bypass (GDB) model, the Markov chains discrete time model, and the direct simulation Monte Carlo (DSMC) method) revealed that the proposed model is more capable of prediction of the hydrodynamic behavior of impinging stream reactors.