Abstract: Distillation column is one of the most common
operations in process industries and is while the most expensive unit
of the amount of energy consumption. Many ideas have been
presented in the related literature for optimizing energy consumption
in distillation columns. This paper studies the different heat
integration methods in a distillation column which separate Benzene,
Toluene, Xylene, and C9+. Three schemes of heat integration
including, indirect sequence (IQ), indirect sequence with forward
energy integration (IQF), and indirect sequence with backward
energy integration (IQB) has been studied in this paper. Using
shortcut method these heat integration schemes were simulated with
Aspen HYSYS software and compared with each other with
regarding economic considerations. The result shows that the energy
consumption has been reduced 33% in IQF and 28% in IQB in
comparison with IQ scheme. Also the economic result shows that the
total annual cost has been reduced 12% in IQF and 8% in IQB
regarding with IQ scheme. Therefore, the IQF scheme is most
economic than IQB and IQ scheme.