Affiliations: Laboratory of Separation and Reaction Engineering, Associate Laboratory LSRE-LCM, Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto, Portugal
Reference: Separation and Purification Technology 173 (2017) 339–356
Abstract: “Removal of carbon dioxide from natural gas for LNG production, can be carried out by cryogenic distillation using a multicolumn sequence to obtain a product stream with less than 50 ppm of CO2. Cryogenic adsorption-based processes, particularly pressure thermal swing adsorption, arise as a reliable and innovative alternative to replace the distillation columns, in particular the last one. In this work, the implementation of a new methodology to design and simulate an industrial scale pressure and temperature swing adsorption process at low temperature (Cryo-PTSA) is presented, in order to produce an almost pure methane stream, with a maximum of 50 ppm of CO2, maximizing the methane recovery. Binderless 13X zeolite was selected as adsorbent and adsorption equilibrium isotherms of methane and carbon dioxide were determined experimentally, in the temperature range 183–473 K, up to 80 bar. The GERG2008 equation of state (EoS) was used during the dynamic simulations to account for deviation from ideal gas law, through the use of REFPROP (REFerence fluid PROPerties) software package…..”
Comments: the authors are using gPROMS to model a pressure swing absorber. PSE Ltd has implemented a CAPE-OPEN thermodynamic socket in gPROMS which enables the use of a CAPE-OPEN Property Package to supply values of thermodynamic properties within a unit operation model. The authors have made use of REFPROP as a CAPE-OPEN Property Package Manager (as supplied by AmsterCHEM) in order to let their PSA model access GERG-2008 within REFPROP. GERG-2008 is an equation of state representing natural gas with high precision. So CAPE-OPEN gives therefore seamless access to state-of-the-art technology.