Carbon-steel corrosion in multiphase slug flow and CO2

Hydrocarbon multiphase flow may exhibit various geometric configurations or flow patterns. One of these flow patterns is known as multiphase slug flow. If CO2 is present in hydrocarbons, the steel pipelines can be corroded as this process is probably enhanced by slug flow turbulence. A hydrodynamic circuit was built to study the CO2 corrosion rates under different slug flow conditions. The experimental results show how the corrosion rate of a carbon-steel electrode varies according to the flow turbulence. The higher slug frequency used in this study was 80 slugs/min. Experimental results for pressure drop and slug length are in agreement with the Dukler and Hubbard [A model for gas–liquid slug flow in horizontal and near horizontal tubes, Ind. Eng. Chem. Fundam. 14 (1975) 337–347] multiphase flow model. Furthermore, the experimental slug frequencies are well correlated by the Shell and Gregory [Correlation of the liquid volume fraction in the slug for horizontal gas–liquid slug flow. Int. J. Multiphase Flow 4 (1978) 33–39] equations in horizontal pipes.