Development of fluid dynamics model for bubble column reactors: application in a vacuum degassing system for liquid metal treatment

• Grant number: 19/08850-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: June 01, 2019
• End date: May 31, 2021
• Field of knowledge: Engineering - Chemical Engineering - Chemical Process Industries
• Principal Investigator: Roberto Guardani
• Grantee: Fabia Bocayuva Carvalho
• Host Institution: Escola Politécnica (EP). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 17/50343-2 - Institutional development plan in the area of digital transformation: advanced manufacturing and smart and sustainable cities (PDIp), AP.PDIP

Abstract

Gas-stirred systems are of great importance to industry in general, with several important applications in the chemical industry, in bioprocesses, and in the treatment of effluents. One of the applications of industrial relevance is the processing of metals, in systems involving adjustment of composition by the interaction between gas and molten metal.In addition to promoting the homogenization of the temperature and composition of the molten metal, the gas injection is used for chemical reactions and elimination of unwanted chemical compounds. In the molten steel vacuum degassing, the argon gas inserted into the system is responsible for the removal of hydrogen and nitrogen present in the metal. Such gases cause detrimental effects on the quality of the final product by adding a porosity to the solidified steel and consequently affecting its strength and service life. Although they are reactors of simple operation, bubbles columns present very complex and little understood flow. Since the fluid is a molten metal, other limitations are added to the study, such as temperature conditions and difficulties related to sample collect and flow visibility. That said, Computational Fluid Dynamics (CFD) modeling is a necessary method to simulate the multiphase flow involved in the process.The present work aims to develop a numerical model by Computational Fluid Dynamics for the treatment of molten steel by vacuum degassing. The model will be used as means of study of the heterogeneity of the system in terms of size argon bubbles distribution and concentration of unwanted gases in the steel (hydrogen and/or nitrogen). The effects on process efficiency, flow velocity and pressure profiles will be determined. The model will be validated through data extracted from the work of Nunis et al. (2015), held at the Technological Research Institute of the State of São Paulo (IPT), research collaborator. This research is part of the project "Institutional Development Plan in the Digital Transformation Area: Advanced Manufacturing and Intelligent and Sustainable Cities (PDIP)" of the Technological Research Institute of São Paulo (Process Fapesp 2017/50348-2), in the line of research Modeling of Biophysical-Chemical Processes. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

CARVALHO, Fabia Bocayuva. Numerical modeling of bubble column reactors: application in a vacuum degassing system for molten metal treatment.. 2021. Master's Dissertation - Universidade de São Paulo (USP). Escola Politécnica (EP/BC) São Paulo.