LIU Yuliang, ZHAI Jian, LI Lumin, et al. Operation and control of extractive distillation for separation of azeotropic benzene/cyclohexane system[J]. CIESC Journal, 2015, (9): 3618-3632.
DOI:
LIU Yuliang, ZHAI Jian, LI Lumin, et al. Operation and control of extractive distillation for separation of azeotropic benzene/cyclohexane system[J]. CIESC Journal, 2015, (9): 3618-3632.DOI: 10.11949/j.issn.0438-1157.20150782.
Operation and control of extractive distillation for separation of azeotropic benzene/cyclohexane system
and extractive dividing wall column distillation is investigated for the separation of benzene and cyclohexane with furfural as entrainer. Based on steady state design
the dynamic control of these three systems is studied with assistance of Aspen Dynamics
and several control structures for each system are presented to handle the feed flow rate and feed composition disturbances. The dynamic simulation results reveal that
for the conventional extractive distillation process
control structure with reboiler duty being proportional to the feed flow rate shows its superiority when it comes to the feed disturbances. In the heat integrated pressure-swing extractive distillation process
the system is sensitive to the pressure. For this reason
pressure-compensated temperature control scheme is proposed based on another control structure
and its dynamic responses reveal that the feed disturbances can be objected effectively. For the extractive dividing wall column distillation process
control structure without vapor split ratio as a manipulated variable
which is easier for to be realized in industrial production and can maintain the product purities at their specifications
is chosen rather than the one with vapor split ratio.