Temperature–enthalpy curve for energy targeting of distillation columns

Effect of feed on optimal thermodynamic performance of a distillation column

“…However, this limitation can be overcome during the generation of IRS curves using the pseudo-binary concept of a light and heavy key [6][7][8][9]11] that defines a practical near-MTC [7]. The invariant property of the IRS curves does not hold rigorously for multicomponent systems because the distribution of the mole fractions of the components depends on the operating reflux of the column.…”

“…The T-H curve for a distillation column quantitatively address the energy saving potential for possible stand-alone modifications as well as process integration. The T-H curve for a binary distillation column at minimum thermodynamic condition (MTC) is generated by solving the coupled mass and enthalpy balances for the reversible separation scheme [5][6][7][8][9][10][11]. The MTC for distillation is defined as reversible operation of a column without any entropy generation.…”

“…The MTC for distillation is defined as reversible operation of a column without any entropy generation. It corresponds to a column with infinite stages having a side exchanger at every stage without any pressure drop and any heat loss through its surface across the column (as discussed in detail by Bandyopadhyay et al [8]). In contrast to binary distillation, the sharpness of separation is generally limited in multicomponent reversible distillation [6] and it is impossible to device a reversible separation scheme for many practical multicomponent separations [10].…”

“…In contrast to binary distillation, the sharpness of separation is generally limited in multicomponent reversible distillation [6] and it is impossible to device a reversible separation scheme for many practical multicomponent separations [10]. The limitations of sharpness of reversible multicomponent distillation may be overcome, for the purpose of generation of the T-H curve, by using the pseudo-binary concept of light and heavy key [6][7][8][9]11]. Dhole and Linnhoff [7] called the T-H curve of a distillation column the column grand composite curve (CGCC) and described a procedure for generating it for a simulated base-case distillation column.…”

Energy intensity and environmental impact metrics of the back-end separation of ethylene plant by thermodynamic analysis

“…One of the thermodynamic methodologies to assess the distillation column operation is the column targeting tool (CTT), which is based on the practical near-minimum thermodynamic condition (PNMTC) approximation representing a practical and close to reversible operation [7,8]. CTT exploits the capabilities for thermal and hydraulic analyses of distillation columns [4,7] to identify the targets for possible column retrofits for (1) feed stage location, (2) reflux ratio, (3) feed conditioning, and (4) side condensing and/or reboiling to reduce the cost of utilities and improve the overall energy efficiency [9][10][11]. The 'carbon tracking' options of the Aspen Plus can help quantify the reduction in CO 2 emission in a simulation environment [8].…”