Eventos Anais de eventos
ENCIT 2018
Brazilian Congress of Thermal Sciences and Engineering
Numerical Analysis of a Cylindrical Heat Source for a Novel Oil Well Abandonment Technique
Submission Author:
Fabrício Pena , SP , Brazil
Co-Authors:
Fabrício Pena, Marcelo De Lemos
Presenter: Fabrício Pena
doi://10.26678/ABCM.ENCIT2018.CIT18-0800
Abstract
Oil well abandonment is a mandatory procedure that isolates the reservoir fluids in order to avoid any kind of environmental contamination. However, current techniques used for well plugging are still extremely expensive and difficult to execute. Aiming to overcome these challenges, a new approach in this area has been studied. The method proposes a certain chemical reaction that would generate enough heat to melt the surrounding materials and, after the cooling stage, the solidified mass would plug the well. A numerical analysis was developed to investigate the amount of heat necessary to change the phase of the material at a certain distance. For the model domain, it was considered an infinitely long cylinder to be a heat source. The pipe surrounding the source was defined as being made of stainless steel. In the outer layer, the dolomite sedimentary stone was treated as homogeneous. Simulations were performed in Ansys Workbench software, which discretized the heat conduction equation using the finite element method. The values of internal heat generation were varied and the results were evaluated in function of time and radial distance. Also, the thermal properties of the heat source material were investigated by varying its thermal conductivity and volumetric heat capacity. Increasing the heat generation resulted in higher temperatures profiles and, consequently, faster melting of the rock. However, the continuous increment of the heat might lead to unmanaged temperatures next to the heat source; therefore, the generation must be controlled along with the reaction time.
Keywords
Oil well abandonment, Numerical analysis, Heat Generation, Finite Element Method
