CFD Analysis of CO2 Sequestration Applying Different Absorbents Inside the Microporous PVDF Hollow Fiber Membrane Contactor

Abstract

The sequestration process of greenhouse contaminants such as CO₂ via hollow fiber membrane contactor (HFMC) is regarded as a promising technology to manage the deleterious impressions of CO₂ on environment such as global warming and air pollution. This investigational paper renders a wide-ranging 2D simulation in order to assess the removal performance of CO₂ from CO₂/CH₄ gaseous stream (containing 80 % CH4 and 20 % CO₂) in the HFMC. As the novelty, the evaluation of CO2 acid gas removal from gaseous mixture applying four novel absorbing agents (potassium threonate (PT), piperazine (PZ), pure water (H₂O) and methyldiethanolamine (MDEA)) is implemented in the HFMC with the aim of introducing a more efficient liquid absorbent for CO₂ sequestration. Model validation is done based on the comparison of mathematical model outcomes and experimental data in a wide range of H2O velocity and confirms a desirable agreement with an average relative deviation (ARD) of approximately 3 % for CO₂ flux. It is perceived from the results that PZ is introduced as the most efficient liquid absorbent for CO2 sequestration and MDEA, PT and H₂O are in the next category (100 % removal using PZ > 96 % removal using MDEA > 89 % removal using PT > 57 % removal using H₂O). The results corroborate that increase in membrane tortuosity and gas velocity negatively affects the sequestration process while increment of module length and porosity improve the separation of CO₂.