Vapor recompression for efficient distillation. 1. A new synthesis perspective on standard configurations

Abstract

The vapor recompression (VRC) distillation scheme is examined and compared with conventional distillation in an analysis spanning fundamental thermodynamics, high-level calculations, and rigorous simulation. The purpose of this article is three-fold: first, it provides greater insight into VRC distillation. Second, it provides a process synthesis tool to rapidly assess whether VRC is likely to be more thermodynamically favorable than conventional distillation for a given split. Third, it may be used to determine if VRC can be implemented practically. The tool presented in the article is consolidated in the form of a single chart, for which only the top and bottom product temperatures are required to determine the outcome. Using this chart, first-pass estimates can be obtained with no calculations whatsoever. The tool, which appears to be the first of its kind in this context, is validated with examples and rigorous simulation.

A perspective on process synthesis: Challenges and prospects

“…It also has a high capital cost due to large equipment used (Felbab et al, 2013). These shortcomings fueled the identification of complex and unconventional distillation configurations.…”

“…Currently, it is estimated that 90% of all separations are carried out by distillation unit(s) (Felbab et al, 2013). Fig.…”

“…4 shows some example configurations. The process synthesis efforts mostly focused on identification of thermodynamically superior (compared to conventional columns) and/or optimum heat pump assisted (e.g., Felbab et al, 2013), heat integrated, dividing-wall (e.g., Caballero and Grossmann, 2013;Shenvi et al, 2013), and, though fewer contributions, reactive columns (e.g., Urselmann et al, 2011). As chemical process industry continues to increase the energy efficiency of its separations, reduce its greenhouse gas emissions and water usage in the future, there are tremendous opportunities for advancing conventional and unconventional distillation train synthesis.…”

Introducing vapor recompression mechanism in heat‐integrated distillation column: Impact of internal energy driven intermediate and bottom reboiler

“…Distillation can be thought of as a combined operation of heat pump and heat engine, where the former adds work to the reboiler and the later removes it from the condenser . In a conventional distillation column (CDiC), the input work is larger than the output work and it makes the operation an irreversible one.…”

“…An excellent overview of the HIDiC structures can be found in Nakaiwa et al and Jana, and references therein. Recently, several research groups are devoted in advancing the HIDiC technology. This relatively new HIDiC column has now entered the large‐scale testing phase in Japan and in the Netherlands …”