Energy-Efficient Diabatic Distillation Using a Horizontal Distillation Column

A conventional distillation column has two limitations causing heavy energy demand: short residence time of liquid flow and excessive vapor flow due to the external reflux flow. These are originated from the vertical structure and adiabatic operation of the column. By utilizing a horizontal distillation column with diabatic operation, the reduction of energy demand of the conventional distillation process was proposed. The separation performance of the proposed column was examined with the distillation experiment, and the column model was developed to calculate the composition profiles of vapor and liquid and the energy consumption. The experiment and simulation of the horizontal distillation column demonstrate that the intrinsic problems associated with the conventional distillation column can be solved to improve its energy efficiency. The computed energy requirement of the horizontal diabatic distillation column was 25.7% less than that of the conventional distillation column calculated from the HYSYS simulation for the product purity of 0.89 mol fraction and a 40 mm vertical column with five stages.