Enhancing efficiency and economic viability in Rectisol system with cryogenic liquid expander

Abstract

AbstractCryogenic liquid expanders have emerged as a potential energy‐saving alternative to Joule–Thomson (JT) valves in cryogenic processes. The potential impact of incorporating a liquid expander into the Rectisol process has not been quantitatively evaluated. This study seeks to assess the effectiveness of replacing the JT valve with a liquid expander in the Rectisol process through the development of thermodynamic models for each component and conducting simulations using the ASPEN software. Additional analyses, including energy, CO2 footprint, exergy, and economic evaluations, are performed for the Rectisol system. Utilizing an expander has been shown to lower energy usage by 2.52% and boost CO2 capture by 5.55%, resulting in a 7.65% decrease in energy expenditure per unit CO2 and a 1.29% rise in total exergy efficiency. Lower expander outlet temperatures and the green power output generated by the expander are the main reasons for these benefits, and the CO2 footprint analysis explains how they work. The application of an expander in the Rectisol process is an economical and low‐risk solution; the payback period is 0.32 years, and the lifetime profit is 53 folds of the investment.