Development and evaluation of a CO₂ capture system using hollow fiber membranes for industrial emissions applications.

Membrane technology has emerged as a selective and efficient option for carbon dioxide (CO₂) capture. However, challenges arise in processing high industrial flows with the same effectiveness as mature technologies. Therefore, studying the process efficiency under real conditions is essential. Membranes of a polymeric nature are promising candidates for implementation on industrial scales.

In this context, this study aims to assess a CO₂ capture system using synthetic and real gases from the textile and cement industry on an experimental scale using a polysulfone hollow fiber membrane contactor, with the goal of developing a pilot-scale system. The experiments were conducted by varying parameters such as the pressure, CO₂ concentration and flowrate. As a result, higher permeate flux values were obtained at the maximum experimental concentration of 12% CO₂ in the feed stream, with a value of 472.54 cm³ cm^-2 s^-1. Additionally, a CO₂ permeance value of 90.98 GPU was achieved along with a CO₂ /N₂ selectivity of 11,37; these values closely approach the Robeson upper bound.

Measurements conducted with gases from the textile industry with a CO₂ concentration of 0.5% reaffirmed the results obtained with synthetic gases of a low permeate flux. In contrast, measurements with gases from the cement plant showed promising results. Also, it was demonstrated that oxygen has a significant impact on the separation efficiency, as it competes with CO₂ for transport sites in the membrane, reaching concentrations of up to 40% compared to the 0.5% CO₂ concentrated in the permeate for textile gases.

In conclusion, tests conducted with gases at higher CO₂ concentrations, such as those from the cement industry, reaffirm the technical feasibility of CO₂ capture using commercial membranes. However, further research is recommended to explore alternative configurations and materials to improve the process purity and efficiency.