Analysis and application of rotating baffle distributors for distillation in a two-rotor rotating packed bed

Liquid maldistribution causes severe loss of separation performance in packed distillation columns. Thus, the investigation of liquid distribution is of particular interest in academia and industry, especially the initial liquid distribution. Liquid maldistribution is present not only in packed distillation columns but also in process intensification equipment such as rotating packed beds (RPBs), which may be operated with metal foam packings. The loss of separation performance is severe especially in multi-rotor RPBs with single-block packing as these lack in liquid distributors in the lower rotor(s). Conventional liquid distribution via nozzles is difficult to implement in the lower rotors. For this reason, a liquid distributor for the lower rotors has been developed and denoted ‘rotating baffle distributor’ (RBD). The RBD resembles a rotary atomizer and is directly mounted to the rotor.

In summary, the RBD design was successfully applied in a 2 rotor RPB in combination with a liquid collector at the intermediate floor. We present a proven concept of numbering up rotors in RPB machines to accomplish separations that cannot be performed in a single rotor due to the limiting number of theoretical stages.