(30b) Hidden Hazards of Pressure Relief Devices in Hydrogen Systems

The energy sector is looking for a sustainable alternative that allows reduce the operational environmental impact to the environment while we can maintain the energy consumption. Specifically, the goal is to find a solution that reduces the carbon footprint emissions.

In this effort, the industry has focused its attention on hydrogen as one of the most promising alternative energy sources using it as an energy production and storage. However, this change brings diverse process safety challenges that need to be considered in this transition. For example, it is known that hydrogen has a higher probability of ignition when released to the atmosphere and the presence of other failure mechanisms as the hydrogen embrittlement has the potential to increase the fire & explosions operational risk.

Given these new hazard characteristics of hydrogen, there is an increase uncertainty related to the risk present when traditional pressure relief devices (PRD) are used in hydrogen systems. Furthermore, although these devices are designed to mitigate a potential rupture due to an overpressure, these could also fail producing leaks acting as the initiated event of an undesired event as a fire or an explosion leading to an uncertainty related to the risk trade-off between the PRD capabilities to mitigate versus the times, they produce an incident.

Due to this uncertainty and motivated by the Dimond Bar incident in 2018, a risk informed review was performed in conjunction with the System Risk and Reliability Analysis (SyRRA) Laboratory of Maryland University related to the PRD in hydrogen systems. This presentation will summarize the reviewed performed where hydrogen specific incidents information was collected and evaluated to identify any potential trend. The presentation will present the contributors found during this evaluation showing breakdown on failure modes, operations, and incident types, while comparing the results to the existing knowledge on PRD reliability from the industry.

The presentation will end by providing the most important conclusion on this evaluation and will provide the next step to be performed in conjunction with the SyRRA in order to reduce the uncertainty related to PRD in hydrogen systems.