Global Effort Targets Onshore Corrosion
A leading technical society is calling on oil and gas industry experts to collaborate on a global project to fight external corrosion of onshore pipelines.
DNV GL, headquartered in Høvik, Norway, is seeking partners in a Joint Industry Project to develop a Recommended Practice for the detection and mitigation of microbiologically influenced corrosion (MIC).
DNV GL is a ship and offshore classification society and a technical advisor to the global oil and gas industry.
MIC is a serious threat to onshore transmission pipelines and can cause unexpected failures, but there is limited knowledge to predict its location and the rate of corrosion, the society says.
"Tiny microorganisms can cause big headaches for onshore pipeline operators, since MIC leads to high corrosion rates at unpredictable locations along a pipeline," said Mirjam van Burgel, project manager for the new initiative.
Coatings & Cathodic Protection
The project will focus on preventing or alleviating MIC by exploring the role of coating condition and cathodic protection; it aims to identify practical means to support pipeline operators in detecting MIC sites by testing and selecting the best measurement techniques.
The project will also develop a decision-support tool to rank the risk of MIC-sensitive areas along a pipeline.
"Onshore pipelines are critical in meeting the growing demand for energy worldwide," said Asle Venås, Pipeline Segment Director-DNV GL Oil & Gas.
"Currently, there are over 230,000km of oil and gas pipelines under construction or planned, in addition to the existing pipeline infrastructure that must continue to operate safely and reliably. DNV GL has deep knowledge of pipelines from performing laboratory and field research projects, including on pipeline corrosion and degradation," said Venås.
The project will result in an industry-wide Recommended Practice that establishes guidelines and recommendations to predict, detect and mitigate the occurrence of MIC.
"The outcome of this project will enable asset managers to effectively lessen MIC, enhance the safety and integrity of their pipeline system, and reduce costs by avoiding costly excavation," said Venås.
Leading Cause of Corrosion
External MIC, caused by microorganisms on the outside of the pipeline, is a leading cause of corrosion failure in onshore pipelines, DNV GL said.
The microorganisms form biofilms that can alter the electrochemical conditions on the surface, inducing corrosion, often in the form of pitting. This type of corrosion is hard to prevent, since the presence of MIC can't be verified without excavating the suspected site for testing, DNV GL explained.
"Currently, there are over 230,000km of oil and gas pipelines under construction or planned, in addition to the existing pipeline infrastructure that must continue to operate safely and reliably," said Asle Venås, Pipeline Segment Director-DNV GL Oil & Gas.
"Even with well-functioning, long-running cathodic protection systems in place, MIC can still occur," said van Burgel. "Though corrosion rates can be reduced, microbiological colonies responsible for MIC do not disappear completely."
Other Pipeline Projects
DNV GL says it is "well placed" to lead the project, having established an MIC Technical Exchange Group earlier this year.
The company currently has three other pipeline-related joint industry projects underway: