Electrochemical Noise - A Potent Weapon in the Battle Against Sour Gas Plant Corrosion

摘要

This paper reviews the application of electrochemical noise (ECN) corrosion surveillance techniques in a large sour gas processing plant operation. The ECN technique has been employed on a real-time basis in several process unit operations for over two years with extremely interesting results. A sulfinol contactor tower where the solvent was contaminated by air is investigated. The use of electrochemical noise in an on-line, real-time basis has positively identified localized pitting attack. The corrosion data when converted to meaningful information and then coupled with real-time plant process information derived from the distributed control system (DCS) provide the corrosion engineer with the requisite tools to look at both the mechanism of corrosion as well as those factors controlling it. It is relatively safe to assume many similar sour gas plants haven't yet considered some form of real time surveillance, since the technology is only emerging and widely considered as unproven. Electrochemical noise when used on-line in real-time will reliably benefit the end-user by providing meaningful information, which is in the realm of near-absolutes, and not merely generalities. The confidence achieved from ECN surveillance will directly impact pressure equipment life and mandatory inspection frequencies.