Downhole corrosion inhibitors for oil and gas production - a review

This review article provides structured guidelines on the selection of corrosion inhibitors for broad applications in downhole for oil and gas wells. It aims to address the shortage in the relevant academic research area and industrial applications. In this regard, the historical and latest research findings regarding these chemicals are assessed. Moreover, it highlights the areas which can be further explored to respond to industrial requirements. This review, in particular, describes the corrosion mechanisms in the downhole tubing and the influential factors such as the partial pressure of CO2 and H2S, temperature, water content, fluid regime, etc. Furthermore, it elucidates the corrosion control methods, including material selection, internal lining, and the application of corrosion inhibitors. The main focus is dedicated to the different types of downhole corrosion inhibitors. Therefore, a holistic review of downhole corrosion inhibition has been discussed, such as the type of chemicals and their application, through a novel and comprehensive classification of the inhibitors. Finally, the injection methods of corrosion inhibitors in the downhole application are evaluated, and implications in introducing novel corrosion inhibitors are explored.