Session: MF-02-02 Materials for hydrogen service II (Joint with C&S)

Paper Number: 62045

Start Time: Tuesday, July 13, 2021, 05:00 PM

62045 - Materials Compatibility Concerns for Hydrogen Blended Into Natural Gas 

Hydrogen additions to natural gas are being considered around the globe as a means to utilize existing infrastructure to distribute hydrogen. Hydrogen is known to enhance fatigue crack growth and reduce fracture resistance of structural steels used for pressure vessels, piping an pipelines. Most research has focused on high hydrogen pressure for the applications of storage (>100 MPa) and delivery (10-20 MPa) in the context of hydrogen fuel cell vehicles, which typically store hydrogen onboard at pressure of 70 MPa. In applications of blending hydrogen into natural gas, a wide range of hydrogen contents are being considered, typically in the range of 2-20%. In natural gas infrastructure, the pressure differs depending on location in the system (i.e., transmission utilizing high pressure versus distribution at low pressure), thus the anticipated partial pressure of hydrogen can be less than an atmosphere or as much as 2 MPa. In this report, it is shown that low partial pressure hydrogen has a very strong effect on fatigue and fracture behavior of infrastructure steels. It is further shown that materials compatibility with hydrogen can be important for systems operating with high stresses as in transmission infrastructure, but the effects of hydrogen pose less of a threat for systems operating at low pressure as in distribution infrastructure. In any case, any system operator considering adding hydrogen to their network must carefully consider the structural performance of their system and the significant effects of hydrogen on structural integrity, as fatigue and fracture properties of all steels in the natural gas infrastructure will be degraded by hydrogen, even for partial pressure of hydrogen less than 0.1 MPa.

Presenting Author: Chris San Marchi Sandia National Laboratories

Authors:

Chris San Marchi Sandia National Laboratories
Joseph Ronevich Sandia National Laboratories