Energy saving in a crude distillation unit with a divided wall column

An energy-efficient crude distillation unit (CDU) with a divided wall column was introduced to evaluate its performance compared to the conventional CDU. The large energy demand of the CDU in the United States—equivalent to more than a half of biofuel produced—was reduced by applying a divided wall column to the unit also known as the energy-efficient distillation column. The divided wall column lowers mixing at feed tray and raises the thermodynamic efficiency of the CDU. The performance evaluation of the proposed unit indicates that the unit saves 37% of heat supply over the conventional unit and cooling by 17%. The economic analysis shows a 9% of investment saving and a 26% decrease in the utility cost from the proposed unit. The thermodynamic efficiency of the proposed CDU is improved by 8%. The modification of conventional CDU was minimal, suggesting an easy revamping of the current conventional CDUs.