CORROSION MONITORING USING ELECTROCHEMICAL NOISE MEASUREMENT WITH BIAS VOLTAGE

摘要

This paper presents the experimental results for CO_2 corrosion of C-1018 carbon steel in arnmultiphase flow system using electrochemical noise measurement.rnA unique biased ZRA mode electrochemical noise technique is utilized to study the corrosionrnprocesses and detect localized corrosion preferentially on a single electrode due to external polarizationrnof the bias voltage under extended exposure times. For full pipe flow at 0.55 m/s liquid velocity, thernexperimental results show that both noise resistance Rn and noise impedance Rornsn can be related to therncorrosion activity. The trends of Rn and Rornsn at different experimental times are also consistent with thernresults obtained from EIS experiments. The experimental results at slug flow of Froude Numbers of 6rnand 9 show that the magnitude of current noise increases with the increase of flow turbulence,rnCompared to slug flow, the current noise fluctuation for full pipe flow is much lower.