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ENCIT 2022
19th Brazilian Congress of Thermal Sciences and Engineering
NUMERICAL STUDY OF SUPERCRTICAL CO2 IN A RADIAL CENTRIFUGAL PUMP
Submission Author:
Jhoan M.C. Cubas , PR
Co-Authors:
Jhoan M.C. Cubas, Henrique Stel, Moisés Marcelino Neto, Rigoberto Morales
Presenter: Jhoan M.C. Cubas
doi://10.26678/ABCM.ENCIT2022.CIT22-0469
Abstract
Because of the high concentration of CO2 in pre-salt reservoirs, separation, sequestration and end destination of this substance has become a major environmental and economic challenge. Traditional technologies used to deal with this problem may render unfeasible, because of high cost and energy consumption that is needed to separate and compress the CO2 until its supercritical state for reinjection back into the reservoirs. An alternative to overcome these challenges is to separate the liquid and the dense gas with high CO2 concentration in the seabed. A centrifugal pump is then used to reinject the CO2–rich dense phase into the reservoir. In this context, the present work aims to evaluate the performance of a multistage centrifugal pump operating with supercritical CO2 through numerical simulations using the commercial computer software ANSYS-CFX. The turbulence is modeled through the SST model, while the variation of the thermo-physical properties of the fluid is calculated through interpolations using a thermodynamic table (Real Gas Proprieties - RGP), obtained from the NIST REFPROP program that is coupled to ANSYS- CFX. The simulations of the pump operating with supercritical CO2 are carried out for different rotating speeds, flow rates and thermodynamic conditions. It is therefore possible to build the pressure, power, efficiency and temperature increment curves, as well as to visualize the flow fields. All this collected information are used to verify whether or not pumps operating with supercritical fluid can be characterized in a similar way when they operate with water. It is important to emphasize that, before starting the simulations witch supercritical CO2, the numerical model is calibrated with experimental data obtained from the pump operating with water. Finally, the results also allowed us to obtain a first impression on the feasibility of using centrifugal pumps to pump supercritical fluids and to contribute to the literature on the subject, which is scarce.
Keywords
centrifugal pump, Supercritical fluid, CFD simulation, performance evaluation
