Influence of cathodic protection and transmission-line proximity on oil-flow electrification

Two reduced-scale closed oil cycles are used to investigate the influence of both the cathodic protection of a pipeline and its proximity to AC power transmission lines on the oil-flow electrification (OFE). For the former case, the results reveal that the OFE is highly dependent on the magnitude of the protection current. The higher the protection voltage the higher is the OFE. Also, the results show that the OFE is enhanced by oil velocity and/or temperature. For the latter case, the results indicate that conductor bundling has a monumental impact on all measured quantities: pipe floating potential, and both corona and streaming currents. In addition, oil temperature causes evident quantitative as well as qualitative changes in the measured streaming current, but no effect was found on both pipe floating potential and corona current. The results are interpreted in terms of physico-chemical and electrochemistry point of view together with electric field computation using a program based on charge simulation method.