Comparison of Consequences of Impact Factors of Accident Escalation Scenarios at Tank with Liquid Hydrogen Sulfide

Abstract

The current risk-oriented approach in the field of industrial safety management, including a scenario approach, involves a quantitative assessment of the risk of the most dangerous and most likely accident scenarios of hazardous production facilities. Most of the possible emergency scenarios are accompanied by a single damaging factor, however, there are scenarios accompanied not by one, but by several damaging factors. Regulatory guidelines usually consider only one such accident scenario, namely BLEVE, which occurs when the containment of capacitive equipment is destroyed under pressure, heated by a flame or heat flow from outside. However, another kind of escalation scenario is possible when the shell of a tank containing superheated liquid under vapor pressure at ambient temperature is destroyed due to a mechanical impact (for example, a large flying debris). Management documents on industrial safety for quantitative assessment of emergency risk on the scale of risk indicators require to evaluate and rank accident scenarios: a) by probability; b) the amount of damage. If there are several damaging factors in the accident scenario, this requires a comparison of these factors with each other in terms of the degree of danger. The present article is devoted to this insufficiently researched issue. In it, according to the criterion of the conditional probability of fatal damage to people in open areas, a comparative analysis and ranking of the hazard of damaging factors of two escalation scenarios of an accident on a tank with hydrogen sulfide were performed: a) BLEVE; b) destruction of the tank at ambient temperature.