Distillation is a process that consumes an extensive amount of energy and
emits an enormous amount of CO2. It is attractive to reduce the energy
consumption and CO2 emission for distillation. A new design of distillation
is proposed by adding turbines in the vapor process streams before the
condenser and after a reboiler to produce domestic electricity. As a result,
this new design helps in reducing energy consumption and CO2 emission. The
key variables are the distillate to feed ratio and the reflux ratio because
they are the direct factors that control the vapor flowrates supplying the
turbines. The distillation of an alkane mixture of C4 - C8 commonly found in
a petroleum refinery was used as a test model to prove the process
feasibility. The energy consumption and CO2 emission of the new process are
reduced to 0.93 - 0.96 and 0.89 - 0.90 of the conventional process,
respectively. This new design increases process efficiency in terms of second
law efficiency by reducing the entropy generation from the conventional
distillation at low distillate to feed ratios and reflux ratios. The
distillation with additional turbines is promising to reduce energy
consumption and CO2 emission and to increase process efficiency.