Application of Triply Periodic Minimal Surface(TPMS) structures for carbon capture processes

Sammanfattning

Carbon dioxide emissions are one of the main drivers of climate change and global warming. The emissions arise from the combustion of fossil fuels, which leads to increased 𝐶𝑂! levels in the atmosphere. To reduce emissions, interest in developing efficient carbon capture methods has grown significantly. Bioenergy with Carbon capture and Storage (BECCS) is currently one of the most promising methods for achieving net negative emissions. A key step of the processis gas absorption through post-combustion capture, where 𝐶𝑂! is separated after biomass combustion via a chemical reaction with a liquid solvent (absorbent). In this work, 𝐶𝑂! absorption was studied in an absorption column packed with Triply PeriodicMinimal Surface (TPMS) structures, manufactured through additive manufacturing (3Dprinting), under varying operating conditions. The effects of liquid concentration, liquid fluidflow rate and temperature were analyzed using potassium carbonate (𝐾!𝐶𝑂") as absorbent, while sodium hydroxide (NaOH) was used for comparison. To investigate how geometry and porosity influence mass transfer efficiency, three different TPMS structures were tested: Gyroid(porosity 75%), Fischer-Koch S (porosity 75%) and Gyroid (porosity 85%). The absorption efficiency was evaluated using a Fourier Transform Infrared Spectroscopy (FTIR) instrument for gas phase analysis, while titration was used to determine the 𝐶𝑂! content in the liquid phase. After the completed experimental work, the results showed that absorption efficiency increased at lower liquid concentrations. When varying fluid flow rate, it was observed that higher fluidf low rate resulted in higher absorption efficiency, while an increase in temperature also resulted in improved absorption efficiency. Among the tested TPMS structures, Gyroid geometry with 85% porosity showed the highest efficiency under all conditions. It was also found that NaOH provided higher absorption efficiency than 𝐾!𝐶𝑂" under the same operating conditions. Overall, the results show that the use of additively manufactured TPMS structures, combined with optimized operating conditions and a suitable absorber, can significantly improve the efficiency of carbon capture. In addition, the results can contribute to the development of sustainable BECCS systems and the design of advanced absorber columns with higher energy efficiency.