Advanced Engineering Analysis for Hydrogen Explosion Risk

Hydrogen production facility site map

Multi energy method blast chart: peak side overpressure

PDL are experts in applying advanced engineering analysis to solve complex technical problems on highly regulated and safety-critical projects. They have extensive experience in calculating explosions, measuring risk and determining safety considerations to validate designs. PDL have completed risk assessments in various forms, such as Structured What-If Technique (SWIFT) analysis. During which, they have engaged in technical discussions with key stakeholders to identify credible failure modes and their consequences. These multi-disciplinary brainstorming sessions have been used to converge on a reduced number of explosion cases to be considered in the subsequent numerical analysis. 

Recently, the PDL team of analysts collaborated with engineering colleagues within the Vulcain Group, to provide their key client with design engineering support during the construction and commissioning of a major hydrogen production facility. 

The team investigated the detailed designs and specifications for the new facility as part of a front-end engineering design (FEED) study. The client relied on the team to establish the overpressure and explosion calculations for a vapour cloud explosion (VCE). A series of safety cases, covering pipe rupture, vessel explosion and vapour cloud explosion, were considered in line with National Standards using the ‘Yellow Book’ Chapter 5. 

The analysts calculated the explosion energy using the TNT equivalence method which required inputs such as the isolatable hydrogen inventories and operational pressures. This allowed known experimental energy releases to be used in the calculation of side-on overpressure and the reflected overpressure, both as a function of stand-off distance. Methods from United Facilities Criteria (UFC) code 3-340-02 for structures to resist the effects of accidental explosions were used to consider partial blast confinement and directional venting. The impact of housing hydrogen compressors using reinforced concrete was therefore quantified. They successfully determined which possible failures at the hydrogen plant would lead to the worst explosive risks. 

The outcome of the RIBA Stage 4 technical design review gave the client confidence to successfully proceed to Stage 5 for procurement, manufacturing and construction. The calculation document was easily adaptable, enabling future plant layout changes to be quickly assessed, minimising explosion risk.                 

Telephone: + 44 (0) 1 434 609 473

 Email:       solutions@pdl-group.com

 Website:    www.pdl-group.com

Published: 19th April 2024