In this case study an unconventional wet gas (WG) gathering pipeline in North America has been analyzed by Internal Corrosion Direct Assessment (ICDA) using a tool that integrates thermodynamic and fluid dynamic capabilities with different proprietary corrosion and erosion models. It has been possible to automatize and guide the acquisition of input data, the choice of ICDA type following AMPP(1) standards and the definition of pipeline regions. The tool automatizes the application of a methodology that comprises flow simulations (steady and transient) coupled to a variety of erosion (solid and liquid) and corrosion predictive models (bottom of line, top of line, localized and microbial corrosion). This has enabled the operator to visualize flow regimes, areas of liquid accumulation, corrosion, and erosion mechanisms, as well as to develop an integrated penetration rate model. A blind assessment has been made and compared to actual detailed examination results via wall loss profiling by intelligent pigging, discrete ultrasound measurements and characterization of retrieved solid. The penetration rate model not only matches the main observed corrosion mechanism (localized corrosion) but also approximates the observed penetration rates with adequate accuracy, within 30% relative error. The model has been calibrated against this data and used for wall loss forecasting.
Transportation of energy carriers (not only oil & gas, but also hydrogen, ammonia, methanol, heating fluids) and carbon dioxide requires the use of extensive pipeline networks that are usually built in metallic materials which are subject to material degradation. Carbon steel being the most prevalent due to its properties, availability, cost, and references.
Carbon steel as well as other metallic materials suffer from corrosion processes. This unavoidable process can be mitigated by proper material selection and using different techniques such as cathodic protection, protective coatings, corrosion inhibitors or a design that considers enough corrosion allowance. Pipelines are subject to corrosion (and erosion) phenomena that hinders and reduces material integrity. In many cases, these pipelines are part of vast and complex gathering, transportation and distribution networks that are difficult to access (in the case of remote, buried, subsea). This makes them difficult to inspect and monitor completely, hence modelling solutions become of great value to the design, operation, and maintenance of these systems.
