On the Adequacy of API 521 Relief-Valve Sizing Method for Gas-Filled Pressure Vessels Exposed to Fire

Safety

Filippo Borroni¹  Marcos Zan Nieto¹  Rudi P. Nielsen¹  Anders Andreasen²  Carsten Stegelmann² 

[1] Department of Chemistry and Bioscience, Aalborg University Esbjerg, Niels Bohrs Vej 8A, 6700 Esbjerg, Denmark;Process and Technical Safety, Ramboll Energy, Bavnehøjvej 5, 6700 Esbjerg, Denmark;

关键词: jet fire;    pressure relief valve (PRV);    vessel rupture;    fire heat load;    pool fire;   

DOI  :  10.3390/safety4010011

来源: DOAJ

【 摘 要 】

In this paper, the adequacy of the legacy API 521 guidance on pressure relief valve (PRV) sizing for gas-filled vessels subjected to external fire is investigated. Multiple studies show that in many cases, the installation of a PRV offers little or no protection—therefore provides an unfounded sense of security. Often the vessel wall will be weakened by high temperatures, before the PRV relieving pressure is reached. In this article, a multiparameter study has been performed taking into consideration various vessel sizes, design pressures (implicitly vessel wall thickness), vessel operating pressure, fire type (pool fire or jet fire) by applying the methodology presented in the Scandpower guideline. A transient thermomechanical response analysis has been carried out to accurately determine vessel rupture times. It is demonstrated that only vessels with relatively thick walls, as a result of high design pressures, benefit from the presence of a PRV, while for most cases no appreciable increase in the vessel survival time beyond the onset of relief is observed. For most of the cases studied, vessel rupture will occur before the relieving pressure of the PRV is reached.

【 授权许可】

Unknown