| Abstract: | Internal cathodic protection of salt water pipelines with the aid of platinized titanium anodes In petroleum production heavy corrosion occurs in the salt water injecting or flooding pipelines. This corrosion can be eliminated either with the aid of a passive protection (protective coating) or, better, by means of an active protection, i.e. cathodic protection with impressed current. While short pipelines can be protected economically with rod anodes, a continuous, partially platinized titanium wire anode has proven must successful for long pipelines. Particular attention must be devoted to the problem of the current feed. The current density required for the protection of bare pipeline surfaces is in the order of 150 mA/sq.m. It can be considerably reduced by combining the active protection with a passive protection by a coating. In connection with the problem of a suitable reference electrode for measuring the protective potential in high pressure pipelines, experiments have been carried out to determine the protective current requirements in a stagnant and a flowing electrolyte respectively. Finally the question of the economy of the process is shortly discussed. |
