Process simulation of dehydration unit for the comparative analysis of natural gas processing and carbon capture application

Dehydration is a common step employed before the transmission of natural gas and/or carbon dioxide in order to avoid hydrate formation. This study is focused on the simulation of dehydration process for the natural gas and CO₂ stream using triethylene glycol (TEG) solvent as the dehydrating agent. This study relates the experiences from the natural gas processing to the application of carbon capture and storage technology for CO₂ dehydration. Two design configurations namely, conventional and stripping gas design are investigated using Aspen HYSYS to compare the performance improvement. The developed simulation model is first validated against the plant data and then the comparative analysis has been performed to understand the analogy between the natural gas and CO₂ dehydration. Finally, a sensitivity has been performed using the stripping gas configuration to test the possible variables that can affect the process performance in terms of dehydrated stream purity, reboiler energy requirement and solvent losses. The results showed that Aspen HYSYS can reasonably predict the dehydration plant performance. The findings of this study also revealed that the CO₂ dehydration process requires more energy compared to the same level of natural gas dehydration.