Corrosion Technology
Electrolyte thermodynamics and kinetics

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MSE Corrosion Consortium info

Corrosion Analyzer

OLI in pipeline corrosion

OLI's Corrosion Analyzer has been effectively used in combination with a fluid flow model for pipelines, to calculate the chemistry effects on the rate of corrosion for a given T, P, and composition.

In this case, the fluid flow model output is used to steer the corrosion rate calculations in Corrosion Analyzer.

Corrosion Analyzer can also supply dew point information, it can calculate the condensate and the composition of the condensate at any point, and it can generate real-solution Pourbaix diagrams that show the corrosive and passivating speciation for a given T, P, and composition in contact with a metal surface.

Why Corrosion Analyzer?

Corrosion Analyzer addresses the cause of chemically-induced corrosion. Clients can investigate and determine the causes of corrosion before they happen, allowing preventive actions to be evaluated and implemented. This includes choosing correct operating conditions and corrosion resistant materials.

Corrosion Analyzer is in contrast to other corrosion programs, that address symptoms by either inspection, experience, or regular corroded material and equipment replacement.

OLI Clients save material, equipment, and time in corrosion-related costs. Corrosion Analyzer makes it possible to screen materials and reduce lab costs, to eliminate unrealistic materials choices and focus lab experiments on likely choices.

Real-solution Pourbaix diagrams, stability diagrams, yield diagrams

Pourbaix's diagrams were created using ideal-solution theory; that is, Pourbaix assumed a water activity of 1. In Corrosion Analyzer, clients can create "real-solution" Stability Diagrams, taking the water activity and the ion-ion interactions into account. The result is the ability to define conditions for metal dissolution, passive films and surface deposits. This in turn can determine optimum pH, concentrations, and EH to minimize corrosion tendencies.

Stability diagrams permit flexible selection of independent variables and graphical depiction of local and global equilibria in various projection. Depictions include EH vs. composition and composition vs. pH for any chemical mixture, including trace components, to assess stable and metastable species in real solutions.

Yield diagrams are a graphical tool ito design the synthesis of compounds (e.g., ceramics) with desired yield for virtually any chemical mixture, including trace components

Rates of chemical corrosion

The Corrosion Analyzer predicts the rate at which a number of oxidation / reduction reactions will proceed, including the metal dissolution reaction. An oxidation / reduction reaction will either consume or produce electrons and must be coupled to another reaction such as the net production of electrons is equal to zero.

Tendency for localized corrosion

The corrosion potential is calculated and plotted against the repassivation potential. In regions where the corrosion potential is larger than the repassivation potential, localized corrosion will occur.

Extreme value statistics (EVS): calculate remaining asset life

Given samples of pit depth, Extreme Value Statistics (EVS) Analyzer calculates remaining asset life using a statistical model

Redox chemistry

Elemental and alloy metal oxidation and reduction reactions for 80 inorganic elements and thousands of species are available in the OLI Databank. The Corrosion Analyzer automatically generates the redox reactions and the resulting species and solves for the equilibrium conditions using its predictive thermodynamic model.

Calculation of electrical conductivity and oxidation-reduction potential (ORP)

Rigorous prediction of electrical conductivity and ORP for multicomponent systems is computed for aqueous solutions. Predictive electricalconductivity over the same range of conditions

Temperature: -50 to 300 C
Pressure: 0 to 1500 bar
Ionic strength: 0 to 30 molal