Chemistry must play a key role in preventing corrosion in oil pipelines

RSC chief executive Richard Pike underlined today the importance of chemistry in preventing oil pipeline corrosion and leakage which can cause enormous economic and environmental damage.

Dr Pike, a former senior executive in the oil industry, has written an article laying out management and scientific challenges presented by corrosion. In an article sent to The Times newspaper he wrote:

"Corrosion is controlled routinely by both chemical and physical means. For example, oxygen is reduced during the water injection process, and biocides are also pumped into the reservoirs. A key step is the injection of corrosion inhibitor chemicals into the pipeline itself, and the use of emulsifiers to limit the separation of oil and water within the pipeline. Furthermore, to stop any settling of water at low points in the line, and also to clear sludge and wax, cylindrically-shaped mechanical 'pigs' with scrapers are sent down the pipeline (driven by the flow of oil), to be recovered with the collected debris at the downstream end.

"Monitoring the effectiveness of these steps is through a variety of techniques. These include the use of small steel discs, or coupons, set into the pipeline so that they are exposed to liquids inside. These can be removed periodically for inspection and measurement without disrupting operations. Another method has a small strip of wire carrying an electric current inserted into the oil flow. As this corrodes over time, its electrical resistance increases."

He added: "There are five important questions company Board members should be asking their senior executives, and which investors and analysts, in turn, should be asking their Boards:

• What is your corrosion management process?
• What has been your experience of corrosion during the last twenty years, what were the outcomes, and how were lessons learned disseminated?
• How does information flow from readings taken on site by technicians, through to analysis and decision-making at senior management level?
• What is your 'corrosion model' for predicting where damage might occur, and how often and in what way is this challenged and verified?
• How does all this compare with international best practice?    

"Many on the receiving end of such questions will feel uncomfortable, because corrosion is not on their radar screens. This has to change. The future will need to address improved handling of data and problem-solving, new materials, corrosion-resistant surfaces and linings, and better understanding and inhibition of corrosion mechanisms throughout the oil supply chain. That will take good management..and clever chemistry."