Innovative compact multi-fluid absorber for CO2 capture using advanced absorbents and microbubble technology

Abstract

Enhancing gas–liquid mass transfer efficiency while reducing operational energy consumption and cost is essential for the industrial application of amine-based CO₂ capture technology. This study proposes a novel compact multi-fluid absorber that integrates spray, bubble and packed to reduce the absorber tower’s size. The absorbent is atomized into fine droplets, which then pass through a foaming network to form more bubbles, increasing the gas–liquid contact area and enhancing CO₂ absorption. Four surfactants were evaluated for their foaming performance, viscosity, and surface tension when complexed with monoethanolamine (MEA). CO₂ uptake and equilibrium solubility of these solutions were tested in a bubbling vessel and analyzed using Nuclear Magnetic Resonance (NMR). Based on these experiments, the most effective absorber was applied to the novel compact multi-fluid absorber. The effects of gas and liquid flow rates on CO₂ performance were tested, revealing relationships between flow rates, bubble sizes, and absorption performance. The results show that the novel absorber improves absorption performance by over 30% compared to the unimproved version. It achieves a CO₂ removal efficiency of 80% at gas–liquid ratios up to 160 and a total absorption rate of 3.77 kmol/m³·h.