Pieter J. Jansens

The furification process in hydraulic packed-bed wash columns

Abstract Hydraulic packed-bed wash columns are continuous solid-liquid separators, which can be applied as the final step in fractional suspension crystallization processes aimed at ultrapurification of organic compounds. In this paper an experimental study and a mathematical model of the purification process in packed-bed wash columns are presented. The developed model can be used to calculate concentration, temperature and porosity profiles along the column axis and to predict the effect of operating conditions on the product purity.

Compressive stresses and transport forces in hydraulic packed bed wash columns

Abstract Hydraulic packed bed wash columns are continuous solid—liquid separators, which combine a virtually complete crystal—mother liquor separation with a highly efficient washing action at high throughput. The applicability of this type of wash column, i.e. for large-scale ultrapurification of organic crystals, depends amongst others on the compressive stresses that are exerted on these crystals upon processing in a hydraulic wash column. In this paper an analytical model is presented which can be used in technical feasibility and scale-up studies to predict the compressive stress profiles that occur in a hydraulic wash column during operation. From calculations based on experimental data, rules were derived on how to minimize the compressive stresses during the operation of a hydraulic wash column.