ABSTRACT Several examples of pipeline corrosion control are discussed. In each account, after the completion of a laboratory evaluation, a corrosion inhibitor program was implemented at the field location. The inhibitor selected was then monitored for its mitigating benefits against corrosion in wet pipeline environments. This occurred where carbon steel constructed equipment was used to transfer various types of corrosive oil and/or gas produced fluids to downstream processing locations. The field monitoring was an integral part of the production companies overall asset integrity management plan, as it insured that the applied inhibitor
maintained the internal integrity of the pipeline asset. In each example cited, the inhibitor program was monitored and optimized accordingly using various on line corrosion monitoring technologies. For each corrosive pipeline environment discussed, the respective on line monitoring tool selected by the production company was value added, confirming that the applied inhibitor maintained internal integrity of the pipeline asset.
INTRODUCTION Oil and gas gathering systems are generally constructed by linking carbon steel sections of pipe (wrapped with some form of external insulation) and then burying the asset in the soil a few meters beneath the surface. Corrosion inhibitor developments for managing corrosion within wet oil and gas production pipelines are well documented throughout the NACE literature. Chemical vendor research and development efforts regarding filmer chemistries that provide mitigating benefits against corrosion in wet sweet (contains CO2 acid gas) and wet sour (contains H2S and CO2 acid gases) oil and gas production pipeline systems is also well documented1. Corrosion inhibitors have also been developed for managing internal corrosion in wet oxygenated production environments2, and provide mitigating benefits against hydrogen induced cracking (HIC) and sulfide stress cracking (SSC) corrosion3.
In each type of oil and gas production pipeline environment, once the selection of appropriate corrosion inhibitor is made, the corrosion control program implemented by the production company generally requires some type of on line monitoring technology to use in: a) validating performance of the inhibitor, b) optimizing inhibitor rates and c) ensuring pipeline integrity is maintained (when operating the assets to transport corrosive oil field production through the equipment). In this regard, a variety of on line corrosion monitoring technologies is discussed - each of which were used in different types of corrosive oil and gas production environments. In each example cited, this aspect of the overall asset integrity management plan provided the pipeline operator with useful monitoring tools that helped insure the internal asset integrity was being maintained.