Captura de CO2 em mistura multicomponente utilizando microrreatores

Abstract

The natural gas associated with the oil extracted from the pre-salt layer presents expressive CO2 contents (>30 mol%), which makes it unfeasible to market directly from the platforms. Thus, CO2 must be removed from the natural gas at least to the concentration required by the ANP, maximum of 3 % mol/mol, to make it commercial. The microreaction system has reached great interest in the last decades due its capacities in the process intensification. In this configuration, the process occurs continuously, with the reactions and the transfer phenomena happening in the individualized form with maximum gradients. A feature to be highlighted in these reactors, compared to conventional chemical reactors, is the higher surface area / volume ratio, which favors a higher yield, selectivity and energy efficiency of the reaction. In this work, the CO2 absorption process in water and amine (MEA) was studied in different kinds of microreactor (System T, Funnel-type microreactor, Type T microreactor and Microreactor Junction T) and evaluated in different gas phase compositions (with N2/CO2 and N2/CO2/CH4). Also, experiments were performed under operational conditions with different gas / liquid volumetric ratio. The microreactors evaluated had a hydraulic diameter between 0.28 and 1.5 mm and were operated at atmospheric pressure and at room temperature. The microreactor system has pumps, valves, microreactor, microseparator, pressure and temperature sensors, and a chromatograph connected in line to analyze the composition of the gas mixture at the system outlet..In general, the flow regime was slug, and the results indicated that the maximum CO2 removal efficiency using the T-junction microreactor occurred with removal efficiency greater than 90% using water as solvent with gas / liquid volumetric ratio of 7:30. The efficiency was 100% when was used MEA solution with concentration above 0.5 M in all operational condition studied.