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.