An NETL review of corrosion sensing technology demonstrates the powerful potential of emerging applications to provide continuous real-time, in-situ monitoring of oil and natural gas infrastructure. This capability empowers industry to prevent pipeline leaks and failures, boosting infrastructure resilience and safety while mitigating unnecessary expenses that are often passed on to consumers via energy bills.

The United States is home to roughly 400,000 miles of oil and natural gas pipelines, which transport vital fuels across the country to meet energy demands. Every inch is susceptible to corrosion, the natural deterioration of metal materials caused by chemical or electrochemical reactions with the environment. Corrosion leads to structural damage that costs billions of dollars each year; however, it’s challenging to detect during routine maintenance and inspections, and current state-of-the-art solutions typically involve periodic inspections rather than real-time monitoring. 

NETL researchers investigating fiber-optic, passive wireless and electrochemical sensing solutions for monitoring pipeline corrosion reviewed current technologies to ensure that the Lab’s work is focused on the most promising applications. Their work, recently published by the international peer-reviewed journal Sensors, evaluated conventional corrosion sensors and emerging technologies in terms of sensor designs, advantages and limitations.

NETL’s analysis affirmed that the sensor technology platforms under development offer some significant advantages as compared to existing state-of-the-art solutions and practices. For example, sensors made from optical fibers offer distinct advantages including nondestructive monitoring, in-situ distributive measurements and greater safety in the presence of flammable natural gas or oil compared to electrical sensors.

Although fiber-optics-based distributed temperature, strain and acoustic sensing techniques are commercially available, distributed chemical sensing (DCS) is an emerging technology that offers a particularly promising option because it facilitates intervention before significant corrosion occurs by identifying conditions likely to lead to corrosion. The current laboratory focus targets DCS within oil and gas pipelines to monitor and localize internal signs of corrosion, such as direct mass loss, presence and chemistry of condensed aqueous phases, and acidic gases.

Passive wireless sensors also possess unique properties that make them conducive for corrosion monitoring, including their ability to transfer energy and information without electrical wiring, adaptability to inaccessible areas and low cost. These sensors use radio frequency signals or acoustics to detect corrosive conditions.

Advanced electrochemical sensors are also under development, representing a near-term technology that may allow for high-fidelity monitoring of humidity and corrosion rates at specific high-risk areas within a natural gas pipeline. Also, research is in progress to add pitting corrosion monitoring capability to advanced electrochemical sensors.

Additional research is required to mature these emerging sensing technologies, particularly for high-temperature, high-pressure and harsh environments in subsurface wells and other extreme conditions.

“With any research endeavor, it’s important to ensure you’re pursuing answers to a question that hasn’t already been answered. The first step is to consult the existing scientific literature and learn from other researchers’ discoveries to focus your work on the most promising technologies,” said Paul R. Ohodnicki Jr., Ph.D., the NETL materials scientist who coordinates the research. “Our review provides a foundation for NETL and researchers elsewhere to build upon as we seek innovative ways to protect America’s pipelines and other critical oil and gas infrastructure.”

Click here to read the full article in Sensors.