Modeling, simulation, and techno-economic optimization of argon separation processes

High-purity argon is conventionally recovered from air by cryogenic distillation, which is a mature, efficient but high-cost technology. In recent years, membrane gas separation technology is starting to emerge illustrating the potential to achieve lower production costs compared to distillation, without compromising the final product quality. In this work, a flowsheet of a conventional cryogenic distillation system for the separation of an oxygen-argon mixture was built and simulated in the gPROMSTM modeling environment. Then, a detailed mathematic modeling framework of a hollow fiber membrane system for the same separation was developed. The predictive power of the model is in a good agreement with theoretically expected results for a wide range of operating conditions. The results indicate that commercially available polymeric membranes are not capable of achieving a high-purity argon product while innovative materials, such as carbon membranes, turn out to be more efficient. Finally, the performance of the membrane process was compared with the cryogenic distillation process using an optimization-based techno-economic analysis. The comparison revealed that the distillation process has a lower operational cost compared to a membrane process for a final product purity of 99.9 mol%.(c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.

Automated summary

This article investigates the conventional cryogenic distillation technology and emerging membrane gas separation technology for high-purity argon recovery from air. The study finds that innovative materials such as carbon membranes are more efficient in the separation process. An optimization-based techno-economic analysis reveals that the cryogenic distillation process has lower operational costs for a certain final product purity.