Lumped model for the assessment of the thermal and mechanical response of LNG tanks exposed to fire

Fires may impact on liquefied natural gas (LNG) process and storage units causing severe damages and potential accident escalation. In the present work, a lumped model able to predict the thermal response of LNG tanks exposed to fire is presented. The model is based on a thermal nodes approach, solving heat and material balances on the equipment exposed to fire, contemplating boiling regime phenomena, heat-up and pressure build up. The model allowed obtaining key indications for the evaluation of the vessel resistance during fire exposure. The model was applied to reproduce the accident scenario occurred at Tivissa (Spain) in 2002 and applied to an industrial case study.