Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Numerical Simulation of Adsorbed Carbon Dioxide Storage Systems for CCS Applications
Submission Author:
João de Sá Brasil Lima , SP , Brazil
Co-Authors:
João de Sá Brasil Lima, Bruno Chieregatti, Armando Zanone, Artur Parisi Dias dos Santos
Presenter: Bruno Chieregatti
doi://10.26678/ABCM.COBEM2023.COB2023-0627
Abstract
Reports of the World Economy Forum showed that, despite the reduction of greenhouse gases in 2020, they are still higher than one decade ago. In response to this scenario, countries have been investing in ways to reduce emissions rates, for example, the generation of electrical energy from renewable sources and direct methods to reduce the amount of gas released into the atmosphere. Another way to circumvent this issue is to withdraw from the atmosphere the gases that already had been emitted, using CCS processes. One promising technology for increasing the storage tanks capacity is adsorption. This research group previously reported the benefits of using an adsorption bed to store natural gas (methane – CH4) in COBEM (2017, 2021). The results indicated that adding an adsorbent material inside the tank raised the amount of gas stored compared to a simple compression. The second part of the study demonstrated that thermal control of the process could increase the gas stored even further. These promising results enlightened that carbon dioxide (CO2) capture and storage systems (CCS) could be implemented using the same technology. This paper modeled and simulated a carbon dioxide capture system by adsorption using Computational Fluid Dynamics (CFD) based on previous works for natural gas adsorption. Despite the similarity of the problems, there are new challenges, such as the affinity of carbon dioxide with the adsorbent and the quantity of energy released during the process, which demands an appropriate procedure to dissipate the generated heat. Hence, this work’s main contribution is to comprehend how the adsorbent material affects the quantity of carbon dioxide stored using numerical simulation. For this purpose, was carried out using a routine programmed in the FreeFem++ platform, considering a cylindrical tank and a known curve for the gas inflow mass flux. The results showed that, considering a target pressure of 3,5 MPa and an inflow volume flux of 30 liters per minute, the amount of CO2 stored is five times greater than the amount of methane under the same conditions. However, the mean temperature inside the CO2 tank is greater (355 K) than the CH4 case (350 K). This is an important issue due to the fact that the capacity of adsorption of the activated carbon decreases when its temperature increases. This difference could restrict the adsorption process and eliminate the advantage of the technology if a thermal control of the process is not applied properly.
Keywords
Adsorption, Carbon dioxide capture, Computational Fluid Dynamics, Heat transfer
