Nishihara, T. ; Verfondern, K.FZJ*

2004
Forschungszentrum Jülich GmbH Zentralbibliothek, Verlag Jülich

Report No.: Juel-4135

Abstract: The High-Temperature Engineering Test Reactor (HTTR) in Oarai, Japan, will be worldwide the first plant to demonstrate the production of hydrogen by applying the steam reforming process and using nuclear process heat as primary energy. Particular safety aspects for such a combined nuclear/chemical complex have to be investigated to further detail. One of these special aspects is the fire and explosion hazard associated with the presence of flammable gases including a large LNG storage tank in close vicinity to the reactor building. A special focus is laid upon the conceivable development of a detonation pressure wave and its damaging effect on the reactor building. A literature study has shown that methane is a comparatively slow reacting gas and that a methane vapor cloud in the open atmosphere or partially obstructed areas is highly unlikely to result in a detonation if inadvertently released and ignited. Various theoretical assessments and experimental studies, which have been conducted in the past and which are of significance for the HTTR-steam reforming system, include the spreading and combustion behavior of cryogenic liquids and flammable gas mixtures providing the basis of a comprehensive safety analysis of the combined nuclear/chemical facility.

Keyword(s): hydrogen production ; reactor safety

1. Sicherheitsforschung und Reaktortechnik (IEF-6)