In the oil and gas industry top-of-the-line corrosion (TLC) has been the cause of numerous pipeline failures and continues to be one of the more challenging corrosion mechanisms to mitigate. Historically, attempts to mitigate top-of-the line corrosion in carbon steel pipelines using chemicals has relied on batch inhibitors (BIs). However, the batching process comes with several drawbacks including a large draw on operator field personnel resources, safety aspects of in-situ pre-diluting with solvents, deferred production, etc., whilst some facilities are not amenable to pigging and batch chemical treatment.

Continuously applied corrosion inhibitors (CIs) are an attractive alternative since they don’t incur these problems whilst reducing or eliminating the need for BI by using a CI helps to lessen chemical handling and logistics with associated safety and environmental, social, and governance (ESG) benefits. Nonetheless, the efficacy of traditional CIs at mitigating TLC has often been limited.

This paper presents data from a focused research and development laboratory program on the development of a versatile continuous CI product, formulated with a unique backbone of chemistries, to mitigate both sweet and sour top-of-the-line corrosion under laminar, low flow conditions whilst also having demonstrated effectiveness under aggressive elevated shear stress conditions which may occur at different locations of the same system at the bottom-of-the-line. Furthermore, the newly developed CI also demonstrates very good secondary properties having good stability along with low foaming and emulsification tendency.