Simulation of an Offshore Natural Gas Purification Process for CO2 Removal with Gas-Liquid Contactors Employing Aqueous Solutions of Ethanolamines

In the scenario of offshore rigs angular indifference, modularity, and compactness strongly influence selection of technology for natural gas purfication. Gas-liquid contactors have such attributes and perform gas absorption without the concerns of packing columns like weight, flooding, gravitational alignment, and water saturation. This paper proposes a model for gas-liquid hollow fiber contactors using aqueous akanolamines for CO2 removal from high pressure natural gas. The model assumes high-pressure compressible flows of both permeate and retentate with full thermodynamics via equations of state. Permeate is approached as a reactive vapor-liquid equilibrium flow of solvent with CO2/CH4 from membrane fluxes. Phase change and reactive heat effects are modeled via mass, energy, and mementum balances written fro permeate/retentate as a differential-algebraic system for dependent variables temperature, pressure and component flows. Profiles are obtained via numerical spatial integration with algebraic resolution imbedded, accounting for permeate reactive vapor-liquid equilibrium with only the molecular species incorporated into a Chemical Theory framework.