Nonequilibrium model and parameter estimation on three-phase distillation in a packed column

A simulation and optimization algorithm using a nonequilibrium model was presented for multicomponent homogeneous and heterogeneous distillations in a packed column. The nonequilibrium model includes the direct calculation of mass and energy transfer between vapour and liquid phases. Computations of quantities such as Murphree efficiencies and height of equivalent to a theoretical plate (HETP) were completely avoided. Experiments were carried out with the heterogeneous azeotropic ternary mixture, n-butanol/water/n-propanol. The experimental data were obtained at total reflux in a diameter of 0.1 m column equipped with the structured packing Rombopak 9M. Both homogeneous and heterogeneous azeotropic distillations were investigated. Based on parameter sensitivity analysis, the effective interfacial area was chosen to optimized according to the experimental studies. The nonequilibrium model is verified to be in good agreement with the experimental data. Optimization results show that the influence of the second liquid phase on separation efficiency in heterogeneous distillations is not identical as compared to homogeneous distillations in the same F-Factors.