Field Monitoring of Corrosion Rates in Oil and Gas Production Environments Using Electrochemical Techniques
|Publication Date:||1 November 2014|
Infrastructure in oil and gas production environments commonly experiences internal corrosion. Therefore, a significant portion of integrity management is devoted to controlling internal corrosion. NACE SP0106,1 SP0206,2 SP0208,3 and SP02104 provide overall guidelines to assess internal corrosion and strategies to control it.
Application of corrosion inhibitors is one of the primary internal corrosion control strategies for carbon steel infrastructure in oil and gas production environments. Periodic monitoring of corrosion is an essential part of corrosion control. More than forty techniques are available to monitor and measure internal corrosion. NACE Publication 3T1995 provides general characteristics, benefits, and limitations of these techniques, as well as procedures to convert the measured parameter to a corrosion rate and hence, corrosion inhibitor efficiency.
Because corrosion takes place in the aqueous environment by electrochemical principles, electrochemical techniques play a vital role in monitoring internal corrosion. These are sensitive monitoring techniques that detect corrosion-related changes as they occur and permit remedial actions to be taken before significant damage occurs. They are defined as direct (i.e., measure the corrosion rate directly), intrusive (i.e., place a probe inside the environment to monitor the corrosion), and realtime measurements (i.e., provide instantaneous corrosion rate, see ASTM(1) standards G966 and G102).7
(1) ASTM International (ASTM), 100 Barr Harbor Dr., West Conshohocken, PA 19428-2959.