ANÁLISE TRANSIENTE DE CONTATORES DE MEMBRANA PARA CAPTURA DE CARBONO

Abstract

The search for the reduction of greenhouse gases has been growing rapidly, especially in relation to carbon dioxide. Due to greater attention in reducing CO2 emissions into the atmosphere, which is the main gas from the fossil fuels combustion for energy generation and other processes involving the generation of CO2 directly or indirectly, several technologies have been studied and applied industrially, with the intention of sequestering the pollutant from those streams. These technologies are commonly known as Carbon Capture and Storage technologies (CCS). Some of these techniques are already quite widespread, although with some disadvantages. This work presents the modeling and simulation of an alternative CO2 capture system to the conventional methods of sequestration: the Hollow Fiber Membrane Contactor (HFMC). The modeling took place through differential molar balances in their respective control volumes (for the gaseous phase, the membrane and the liquid phase), giving rise to a system of partial differential equations, which depend on the time and axial coordinate of the equipment. The system was solved using the past finite differences method, where it was converted into a system of ordinary differential equations in two different ways: discretizing space (giving the solution to time) and discretizing time (solving the system in space). The method implementation was done in Python software, where a differential equation solver was used. The model results were concrete and consistent with what is shown in the literature, and it was possible to observe the behavior of the process under certain simulation conditions. Such conditions (of volumetric flow rates and equipment geometry) were adapted to achieve a 90% CO2 capture ratio. Although the modeling was simplified, and thermal and kinetic effects were not taken into account, good results were obtained.