What are the current and emerging trends and focus areas for hydrogen conversion of pipeline infrastructure?
A commonly asked question facing the pipeline industry with respect to hydrogen is “Can we transport hydrogen in legacy pipeline systems?” The answer is Yes because hydrogen has been transported in carbon steel pipelines for many decades. The real question is “How does the industry plan to assure itself and the general public that we CAN safely transport hydrogen within those many thousands of miles/kilometers of pipelines and maintain an acceptable risk profile?” The hydrogen arena is still in many ways a blank slate, with research gaps and, as yet little regulatory input. Little to no prescriptive guidance is available, and what is available may not be suitable for all blended hydrogen situations currently being considered by the industry.
Regardless of the research and regulatory gaps, the pipeline industry has the opportunity, the expertise and perhaps the responsibility to drive the progress of infrastructure conversion. At the recent Canadian Hydrogen Conference, a statement was made that transition to a hydrogen energy economy is likely a multi-trillion US dollar effort. Certainly, there is plenty of work to go around. The concept of “getting there” quickly for the industry likely outweighs “getting there first” but collaborative and transparent sharing is necessary.
Much of today’s research focuses on material compatibility with hydrogen. In the legacy pipeline space, questions linger about how best to address the properties of materials within the systems. With records often incomplete or missing, the need for technology to accurately determine in-situ properties is vital. Armed with accurately known material properties, one of the biggest needs for the pipeline industry is a better understanding of how latent flaws in legacy pipe will behave upon prolonged exposure to hydrogen.
Other important focus areas for pipeline transport of hydrogen in addition to positive material identification include odorization, leak detection, metering, and end-use equipment compatibility. Blending percentage into natural gas is a discussion point for operators today, much because it attempts to address the end-use requirements, but other operating factors must also be evaluated to ensure that public concerns regarding safety and the financial aspects of transport in terms of both gas heating value and carbon offset are adequately addressed.
What are the impacts of pipeline service conversion to hydrogen on the infrastructure and future capacity needs?
Hydrogen transportation requires that pipeline operators augment the threat assessment methodology for their pipelines. The need to identify those potentially threatening conditions that can become critical defects is of great concern. While the general behavior of carbon steels in the presence of hydrogen is known; primarily the enhanced potential for hydrogen embrittlement and the associated increase in fatigue crack growth rate, more work is necessary to more precisely understand the impact existing, and sometimes currently acceptable flaws including cracks, crack-like indications, surface breaking manufacturing features, or even pitting corrosion.
Assessment methodology such as In-Line Inspection must also improve. The kinetics of hydrogen with respect to pigging in pipelines and the need to identify smaller size flaws with ultrasonic precision dictate technological advances necessary to keep pace with industry needs.
Regulatory agencies rarely have people who have the necessary skill sets to define specific design, construction, operations, and maintenance procedures for hydrogen pipelines. They will turn to the industry to present viable solutions which inform the development of the necessary standards, recommended practices, and regulations.
How does Dynamic Risk support operators in this Emerging Fuels space?
Dynamic Risk is staffed with Subject Matter Experts in the areas of pipeline integrity and risk assessment. This uniquely qualifies us to support Operators in the evaluation of their pipeline systems being considered for conversion to hydrogen service. Expert technical evaluation of materials, inspection results, and operating conditions allow us to guide operators on the most important design parameters within their pipeline systems for hydrogen transportation. Our industry and regulatory-accepted methodologies for Engineering Assessments make us a prime partner to gain approval for conversion plans from regulatory and municipal stakeholders. Finally, our expertise in risk assessment, both qualitative and quantitative, makes us eminently qualified to identify, assess, present, and develop mitigative activities for risks associated with converted systems.
About the Author:
Gary Yoho, Principal Consultant
Gary Yoho has 40 years’ service in the pipeline industry with comprehensive experience in pipeline design, construction, integrity management, operations, and project management. Gary has developed Integrity Management Plans for liquid and gas pipeline systems and facilities, both onshore and offshore. He has developed or guided the development of crack management procedures, waterway crossing management procedures, hydrostatic testing procedures, and welding procedures in accordance with API 1176, API 1133, API 1173, API 1110, and API 1104/ASME Section IX. He has also been intimately involved with the development and implementation of Pipeline Safety Management Systems.
As a Dynamic Risk Principal Consultant, Gary has led or contributed to engineering assessments and risk evaluations for operating pipelines, pipeline conversions, pipeline return-to-service and regulatory mandated activities in addition to the writing of technical procedures for pipeline maintenance and operations. Gary currently is serving as Dynamic Risk’s point consultant for pipeline issues relating to the transportation of gaseous hydrogen. He recently presented a paper at the 18th Pipeline Technology Conference (ptc) 2023 discussing “Considerations and Challenges when Assessing the Conversion of a Pipeline to Hydrogen Service”.