Abstract
In this work a VOF-based 3D numerical model is developed to study the influence of several operative parameters on the gas absorption into falling liquid films. The parameters studied are liquid phase viscosity, gas phase pressure and inlet configuration, liquid–solid contact angle and plate texture. This study aims to optimize the post-combustion CO2 capture process within structured packed columns. Liquid phase viscosity is modified via MEA (i.e. monoethanolamine) concentration. The results show that an increase in liquid viscosity reduces the diffusivity of oxygen within the liquid film thus hindering the efficiency of the process. Higher pressure carries an absorption improvement that can be attractive to be applied in industry. The simulations show that enhanced oxygen absorption rates can be achieved depending on the velocity of the gas phase and the flow configuration (i.e. co- and counter-current). Also, the importance of wetting liquid–solid contact angles (i.e. less than 90°) is highlighted. Poor liquid–solid adhesion has similar effects as surface tension in terms of diminishing the spreading of the liquid phase over the metallic plate. Finally the influence of a certain geometrical pattern in the metallic surface is also assessed.
Highlights
Different techniques exist in order to reduce CO2 emissions to the atmosphere: renewable energies, efficiency improvement of current energy generation systems and carbon capture and storage (CCS)
The validation of the present model for both hydrodynamics and mass transfer is discussed in our previous work (Sebastia-Saez et al, 2013)
The mass transfer model was validated by comparison with the experimental results from Xu et al (2009), who studied the physical absorption of propane into a toluene liquid film in an inclined plate
Summary
Different techniques exist in order to reduce CO2 emissions to the atmosphere: renewable energies, efficiency improvement of current energy generation systems and carbon capture and storage (CCS). Renewable energies would be the definitive option to avoid emissions but their current cost is not competitive compared with fossil fuel technologies (Khalilpour, 2013). Recent studies suggest that fossil fuels are expected to play a dominant role during the few decades for power production (Odenberger and Johnsson, 2010). CCS is the technology that deals with the process of capturing CO2 from a flue gas mainstream, transport it and store it into geological formations. Three different approaches exist to mitigate CO2 emissions: pre-combustion, oxy-fuel technology and post-combustion carbon capture. Precombustion extracts carbon from the fuel before combustion and is
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
