Design And Optimization Of Dividing Wall Column With Internal Heat Integration

Distillation, which is the separation technique most widely used in the chemical and petrochemical industry, is very energy consuming. To explore energy-efficient approaches of distillation process has become particularly important with the requirements of energy and environment protection getting increasingly serious. One attractive alternative for reducing the energy requirement is to use dividing-wall column configurations.Dividing-wall column(DWC) is a special structure of fully thermally coupling distillation(Petlyuk) by using only one distillation column with a dividing wall installed to separate the prefractionation from the main column section. The energy requirements and the concentration profiles of the thermally coupled columns and the divided-wall column are completely identical. However, the tower and the corresponding pipelines of divided-wall column are less than the thermally coupled distillation columns, leading to a less capital investment.Although dividing-wall column has shown a great advantage in terms of reducing energy consumption and equipment investment, the energy requirement for such arrangement is not at minimum when ignore the heat transfer between the wall. So the horizontal heat transfer was considered in the study.A Fenske-Underwood-Gilliland short-cut method is proposed to estimate the basic structure of dividing-wall column separating of a ternary ideal mixture containing hypothetical components A, B, and C. With these primary specifications, it is rigorously simulated used the software of Mathematica, the Newton-Raphson method were used to calculate the temperature, concentration distribution and the liquid-vapor flow rate of each trays. Then the horizontal heat transfer was arranged to explore the potential of dividing-wall column.The results obtained indicate the heat coupling between the column sections can save the energy of dividing-wall column. Moreover, a further reduction of energy consumption with adjusting the number of the coupling plates, the heat transfer areas, the coupling locations and the relative volatility.