A MECHANISTIC MODEL FOR CO2 CORROSION OF MILD STEEL IN THE PRESENCE OF H2S ACCOMPANIED BY SIMULTANEOUS IRON CARBONATE AND IRON SULFIDE FILM GROWN

摘要

A number of CO2 corrosion models can predict successfully the "worst case" corrosion rate but fail when more complex effects need to be included such as protective scale formation and the H2S effect. A comprehensive integrated CO2 / H2S corrosion – multiphase flow model package has been built that takes into account the effect of most important variables and processes in internal pipeline corrosion including the effects of H2S. In the text below it is described how the model can account for formation of iron carbonate and iron sulfide scales and predict their morphology as well as the effect on the corrosion rate. The model has been extensively calibrated with laboratory data and compared with limited field data.