Situation and outlook for cathodic protection technology of oil & gas pipeline

In this paper, popular cathodic protection criteria in China and their deficiencies are presented. Current calculation methods and numerical simulation techniques for cathodic protection are described, and future development of such techniques is expected. Moreover, the cathodic protection equipment available now, together with their deficiencies, is introduced. As to the development of cathodic protection technology, some recommendations are put forward. Firstly, in respect of cathodic protection criteria, basic electrochemical theory should be considered to establish perfect cathodic protection standards, including those for pipelines operating at high-temperature or with stray current interference. Secondly, in respect of cathodic protection calculation, numerical simulation should be promoted to regional cathodic protection design, cathodic protection theory analysis of large-scale pipeline network, and pipeline cathodic protection and anti-corrosion coating analysis. Thirdly, in respect of measurement of cathodic protection potential, the coupons method can be used for evaluating the cathodic protection performance and density of cathodic protection current. Fourthly, in respect of compatibility of cathodic protection and anti-corrosion coating, the pipeline corrosion control system should be optimized generally. Fifthly, in respect of cathodic protection equipment, a digital cathodic protection system should be developed according to operations of oil/gas pipeline, so as to essentially improve the level of cathodic protection technology and management.