Captura e mineralização de CO2 em processo de recirculação de amina modificado

Abstract

In recent years, extreme weather events have increased in several regions of the hemisphere due to rising global temperatures. Among the gases that intensify the effects of global warming, carbon dioxide (CO2), produced mainly by burning fossil fuels, is the main culprit for the strengthening of the phenomenon. Therefore, efforts have been made to reduce and neutralize the high concentration of CO2 and support energy transition measures, methods, and technologies to eliminate its emission. Carbon capture, storage, and utilization (CCUS) plants have been studied to integrate and combine technologies with recovery potential, including absorption, adsorption, amine recirculation, and mineral carbonation. Therefore, it is necessary to understand the interaction between these technologies. The objective of this work is to investigate the possibilities of the amine recirculation process combined with the mineral carbonation process. Experimentally, CO2 capture was performed in the presence of MEA solutions of different compositions (10%, 20% and 30% v/v) under controlled operating conditions (pressure, gas and liquid flow rate, and temperature). The mineralization reaction was carried out under defined conditions, with different concentrations of CaO and MgO (2%, 5% and 8% m/m) and temperatures (25, 50 and 70 ºC). The carbonated products and the regenerated MEA solutions obtained after the combined process were evaluated from the morphological, thermogravimetric and physicochemical points of view. Based on the results presented, the combined process performed well under the studied conditions, with CaCO3 and MgCO3 conversion values above 50% at dosages at the highest temperature conditions. Furthermore, the regenerated MEA solutions presented properties and characteristics similar to the original solution. These results indicate the viability of the methodology, enabling its application and expansion to large-scale CO2 processing plants, associated with the valorization of the process with the generation of high-value-added co-products.