Study of corrosion scale formation from quantum mechanics simulations to a continuum model

摘要

Among the main corrosion precursors present in oilfield environments are H_2O, CO_2 and H2S, which lead to the formation of different solid corrosion products, such as iron sulphides and iron carbonates. The presence of these scales can lead to a significant reduction in corrosion rates. Understanding the formation of iron sulphides is complicated by the existence of several stable and metastable Fe-S compounds1' . To date a comprehensive understanding of the phase stability has not been achieved3'4. Atomistic level details of the thermodynamics and dynamics of scale formation can, however, be based on systematic ab initio calculations. Here we present the results of calculations addressing both the bulk phase stability of the sulphides and of simple model of scale growth precursors on iron surfaces. These calculations are used to characterise the structural, electronic and thermodynamical properties.