Global minimization of total exergy loss of multicomponent distillation configurations

Abstract

The operating cost of a multicomponent distillation system comprises two major aspects: the overall heat duty requirement and the temperature levels at which the heat duties are generated and rejected. The second aspect, often measured by the thermodynamic efficiency of the distillation system, can be quantified by its total exergy loss. In this article, we introduce a global optimization framework for determining the minimum total exergy loss required to distill any ideal or near-ideal multicomponent mixture using a sequence of columns. Desired configurations identified by this new framework tend to use milder-temperature reboilers and condensers and are thus attractive for applications such as heat pump assisted distillation. Through a case study of shale gas separations, we demonstrate the effectiveness of this framework and present various useful physical insights for designing energy efficient distillation systems.

Minimum reflux calculation for multicomponent distillation in multi‐feed, multi‐product columns: Mathematical model

“…Thereafter, this assumption has been widely accepted and adopted by a number of articles, including some of the recent ones such as Caballero and Grossmann, 14 Ruiz-Marín et al, 47 Adiche and Vogelpohl, 48 G omez-Castro et al, 49 Adiche and Aissa, 50 Nallasivam et al, 18 Jiang et al, 13,51,52 and Tumbalam Gooty et al 19 As we can see, in order to generalize the Underwood method to MFMP columns, existing shortcut methods incorporate several additional assumptions and constraints which cause the resulting models to only be valid under restricted settings. This work is the first to develop an accurate and easy-to-use shortcut based method to estimate the minimum reflux ratio for a general MFMP column without needing extensive simplifying assumptions.…”

Alternative Processing Sequence for Process Simplification, Cost Reduction, and Enhanced Light Olefin Recovery from Shale Gas

“…Besides the benefits described above, the proposed processing sequence also opens up an unprecedented opportunity to revisit conventional process-intensification strategies. Most literature studies to intensify this process have focused on the development of alternative technologies and the integration of adjacent unit operations. ,− For example, Halvorsen et al studied a dividing wall column configuration for the front-end NGL fractionation. Collins et al studied the use of a membrane reactor for catalytic dehydrogenation with a pure C 3 H 8 feed.…”

Classification and Comparison of Dividing Walls for Distillation Columns

“…However, when work rather than heat is used as in a cryogenic distillation or a heat pumped distillation, results could be quite different [29]. In such cases, for optimal dividing wall choice, it is essential to perform appropriate optimization using exergy as described by Agrawal and coresearchers [29,30].…”