Impact of structure of a rotating zigzag bed with block-rotor on separation performance in distillation

Abstract

A high centrifugal force is used to intensify distillation, which is called Higee distillation. Rotating zigzag bed(RZB) has successfully applied in the industrialization of Higee distillation. In order to develop further the RZB, a RZB with zigzag block-rotor(RZB-BR) was provided. Rotating as a whole, the RZB-BR rotor had a set of concentric circular baffles between two disks, providing a zigzag passage for gas/liquid flow. A total reflux distillation experiment was carried out with an ethanol-water system to investigate separation efficiency, gas pressure drop and power consumption. A power consumption efficiency was proposed for the first time to compare power consumption of Higee devices with various structures and sizes. The RZB-BR had good performance, and the fine steel bars that were fixed to the baffles as well as the upper and lower disks could improve the mass-transfer. Compared to RZB and RPB, the separation efficiency of the RZB-BR was lower and higher than RZB and RPB respectively, and the pressure drop and power consumption of the RZB-BR were both lower and higher than RZB and RPB respectively. Therefore, the RZB-BR may be an alternative to the RZB and RPB, applied in Higee distillation.