Continuous Crystallization Using Ultrasound Assisted Nucleation, Cubic Cooling Profiles and Oscillatory Flow

Continuous tubular crystallizers have the potential to reduce manufacturing costs and increase product quality. However, designing tubular crystallizers is a complex and challenging task as crystallization is a complex, multiphase process with a propensity for fouling and clogging. While several designs have been proposed to overcome these issues, these designs are either unproven or poorly scalable and complex. In this work a continuous crystallizer is designed and evaluated to mitigate these issues. The tubular crystallizer combines a novel method to obtain a cubic cooling profile to control the supersaturation, ultrasound to induce nucleation and oscillatory flow to improve mixing and minimize fouling and sedimentation. The results show that the crystallizer was able to operate for more than 4 h without clogging, with high yields and a narrow particle size distribution. The design proposed here is therefore considered a viable approach for continuous crystallizers.

Oscillatory flow of casson fluid between parallel plates with an inclined magnetic field

The study of heat and mass transfer of oscillatory casson flow inporous medium subject to an inclined magnetic field, radiative heatflux and heat source is presented. It is supposed that Casson fluid islittle conductive and produced emf is insignificant. The solutions ofcoupled partial differential equations of velocity, temperature and con-centration profiles are found using Galerkins technique of finite elementmethod. The effect of various parameters such as Reynolds number Re,Grashoff number Gr, Solute Grashoff number Gc, Peclet number Pe,Hartman number Ha, Scmidth number Sc, Permeability parameter K,Radiative parameter R, Heat generation parameter S, Chemical reactionparameter Kr and frequency parameter w on velocity, temperature andconcentration are shown graphically and skin friction, Nusselts numberand Sherwood number are discussed by tables.