2007 Spring Meeting & 3rd Global Congress on Process Safety

(98a) The Performance of Random Packing for High Pressure Distillation Systems

Authors

Cai, T. J. - Presenter, Fractionation Research, Inc.
Zuiderweg, F. - Presenter, Fractionation Research, Inc.
Shariat, A. - Presenter, Fractionation Research, Inc.
Chen, G. - Presenter, Praxair, Inc.
Yanagi, T. - Presenter, WorleyParsons


The experimental results of 50 mm Pall Rings with high pressure systems are presented and discussed. The packing was tested in a 1.22 m high pressure distillation column with a bed length of 3.66 m at Fractionation Research, Inc. (FRI). The tests were conducted with the iC4/nC4 system at various column pressures of 11.4 to 34.4 bar. The experimental results show unusual HETP trend and higher HETP than expected. The measured data also have a high degree of scatter for high pressure systems. The data are compared with those of the Nutter Ring No. 2.5 with the same system and operational pressures. It is found that the distributors affect the packing performance significantly. The possible causes of the unexpected HETP and unusual trend are discussed including the effect of samplers, vapor back-mixing, and condensation. Finally, a larger than usual safety factor is suggested for the random packing application at high pressure systems.