Risk Assessment and Consequence Analysis of Fire and Explosion in a Vinyl Chloride Monomer Tank by PHAST

Fire and explosion are the most important and common consequences of released chemicals. In present study the consequences of jet fire and explosion in a Vinyl Chloride Monomer (VCM) tank was investigated.

In this applied study, fire and explosion from 16 material releasing scenarios were investigated using PHAST.7.11 software. The tank’s temperature, pressure, volumes and shape were 70OC, 9bar, 3600m3 and spherical respectively. The meteorological data were categorized based on Pasquil method. The mortality rate and danger radius for each scenario were calculated and analyzed.

The smallest (11m) and the largest (79m) radius effected by the explosion pressure wave belongs to 50mm slot release and the complete rupture respectively. The highest pressure wave (1bar) is produced from a complete rupture extending from 0-80m from the gas cloud center that cause the 10.27 and 2.57% mortality rate of day and night working shifts respectively. The largest and the smallest areas covered by the jet fire are 1861 and 185m2 respectively and the largest and the smallest radius covered by radiation heat from this fire are 59.4 and 20.4m respectively.

Any possible leakage from the tanks will have catastrophic consequences, indicating a very high and unacceptable level of risk. As a result, considering the levels of damage caused by the explosion wave, the necessary measures for the prevention of these consequences are imperative.