Characteristics of a two-stage counter-current rotating packed bed for continuous distillation

A novel two-stage counter-current rotating packed bed (TSCC-RPB) was specially designed for and applied in continuous distillation. The hydrodynamic characteristics of the TSCC-RPB including gas pressure drop and flooding performance were studied with air–water system and air–glycerin solution system. The effects of rotational speed, gas flow rate, liquid flow rate and liquid viscosity on the pressure drop and flooding were examined. Continuous distillation experiments were carried out in the TSCC-RPB with an acetone–water system at atmospheric pressure. The separation efficiency is presented in terms of the number of theoretical plates (NT) and the effects of the operating parameters, such as rotational speed, feedstock temperature, feedstock concentration, and reflux ratio on the separation efficiency were investigated. Experimental results showed that the TSCC-RPB is an efficient gas–liquid contactor having a NT of 4.94–11.57 with a packing thickness of 200 mm.