2022 Spring Meeting and 18th Global Congress on Process Safety Proceedings
(22a) Redefining the Upper Bound Curve for Process Intensification in Natural Gas Processing
Authors
The present paper proposes the use of a process intensification approach that takes into account the variation of gas permeability with upstream pressure. Therefore, an approximate model based on plasticization pressure and permeability parameters at plasticization was proposed for defining the Robeson upper bound curve of membranes used for high pressure gas separation. The model which was derived by applying the partial immobilization assumption to the fundamental model of solution - diffusion was used for selecting the best membrane material which was used in this work. A comparative study of the traditional solvent-based CO2 separation and membrane-based gas separation techniques was carried out on a gas separation plant using the process intensification approach. The study was performed using process intensification metrics including mass intensity; waste intensity; productivity/size ratio; productivity/weight ratio; flexibility and modularity and a multi-objective optimization method. The results obtained indicated that huge saving is possible by installing a plasticization resistant membrane in an area which involves high pressure CO2 separation. Furthermore, this idea is justified since natural gas is often obtained directly from gas wells at pressure ranging from 20 to 83 bar and compositions between 4 and 50% CO2.