Experimental validation of a flexible modeling approach for distillation columns with packings

Abstract

The two main concepts for the modeling of distillation columns are the equilibrium-stage (EQ) and the nonequilibriumstage (NEQ). A model is presented which combines decisive features of both conventional concepts. Based on the idea of a reduced nonequilibrium-stage (RNEQ), this model can be used for the simulation of distillation columns with packings. In contrast to the conventional NEQ approach, this model neglects the influence of liquid side mass-transfer coefficients, which ultimately allows to come up with only one empirical equation describing the overall mass transfer. Thus, a considerable reduction in model complexity is reached, which allows for an efficient consideration of new experimental distillation results. Fitted to experimental data, the model is able to predict, how different pressures and chemical systems might affect the separation efficiency. By comparing calculation results with experimentally determined separation efficiencies for three different packing types, these valuable RNEQ qualities are illustrated. V C 2014 American Institute of Chemical Engineers AIChE J, 60: [3833][3834][3835][3836][3837][3838][3839][3840][3841][3842][3843][3844][3845][3846][3847] 2014

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