Investigating the performance of an ultrasonic-assisted rotating packed bed reactor for micromixing efficiency enhancement

The Micromixing plays a key role in the most of industrial processes; enhancing its efficiency is very important issue. In this study, a typical rotating packed bed (RPB) reactor equipped with blade packing and high frequency ultrasonic transducers were designed to study micromixing efficiency using iodide/iodate reaction. The utilized ultrasonic transducers were ultrasonic atomizer humidifier with a frequency of 1.7 MHz. Taking advantage of both controllable high gravitational force and induced effects of high frequency ultrasound, simultaneously, in a small volume reactor is the novelty of the present work. The effects of different parameters like rotational speed, volumetric ratio, acid concentration, ultrasonic power and number of activ transducers were investigated with and without ultrasound field. With increasing the rotational speed and volumetric flow, the segregation index decreased and with increasing the acid concentration and volumetric ratio, the segregation index increased. In all of experiments, the segregation index decreased significantly under ultrasound field. Moreover, with increasing the ultrasonic power and number of active transducers the segregation index decreased. The obtained results indicated that the relative segregation index increased up to 41.1% under 1.7 MHz ultrasound field. Therefore, high frequency ultrasound waves can intensity micromixing, even in a high efficiency equipment like RPB.