The effect of mass transfer on corrosion in oilfield production processes by wastewater enriched with CO2: Computer-aided modeling and experimental verification

Abstract

In the present study, a mass transfer based theoretical model to investigate the rate of corrosion of an alloy of mild steel in a solution of a carbon oxide-wastewater from oilfield with and without acetic acid is presented. Electrochemical polarization data are evaluated using β – model which takes into account the influence of mass transfer on the corrosion process. An algorithm is built, and two software programs are used in evaluating the corrosion kinetics parameters. The effect of correction factor of mass transfer, which depends on β, on the kinetic reaction parameters is evaluated.The average value of β is 0.42 suggesting a mixed control corrosion mechanism. A mass transfer correction factor (λ) is evaluated at different temperatures and speeds of rotation in the absence and presence of the protective film. The values of λ ≈1 at low overpotential and it decrease as over potential increases. The polarization resistance values in the absence of acetic acid are larger (≈0.5 Ω. cm2) than the polarization resistance values in the presence of acetic acid (≈0.1 Ω. cm2), due to the formation of the protective film. The results are further analyzed by dimensionless groups and empirical equations are obtained with high correlation coefficients.

Keywords

• Corrosion
• Steel
• Acetic acid
• Wastewater
• Mass transfer
• Algorithm