Computational Fluid Dynamics Simulation of 13CODistillation in Structured Packing

 
                           Hu-Lin Li1,2，Yong-Lin Ju1，Liang-Jun Li2，Da-Gang Xu2

   1 Shanghai Jiao Tong University, Institute ofRefrigeration and Cryogenics, Shanghai,
                                                              China.

                  2 Shanghai Research Institute of Chemical Industry,Shanghai, China.

Physical 3Dmodels were established for corrugated packing used in the enrichment of theisotope 13C. Computational fluid dynamics (CFD) simulation results indicatedthat common corrugated packing was not well wetted when used for isotopedistillation. It is concluded that liquid misdistribution in the packed towerresults from the structure of the packing rather than from the height of the packingbeds. The existence of entrainment was also demonstrated by CFD simulation. Itis proved that mass transfer equations based on the Nusselt theory are notsuitable for distillation calculation in such a corrugated packing system. By comparison,the recently developed structured packing model with a corrugation geometrybased on the right-angled triangle, known as Zigzag-pak, describes vapor-liquiddistribution properties well and has significant advantages over commoncorrugated packing due to its better liquid distribution character.

Keywords: Corrugatedpacking, Cryogenic distillation, Isotope 13C, Transferintensification, Zigzag-pak