Analysis of Consequences for Reactor Accident Under Vapours Cloud Explosion Scenario Based on Release Rate Changes
DOI:
https://doi.org/10.63746/njtd.v22i4.2932Keywords:
ALOHA, MARPLOT, Reactor Accidents, Release Rate, Vapor Cloud ExplosionAbstract
This study investigates the consequences of vapor cloud explosions in chemical reactors, focusing on the impact of varying leak sizes (2, 5, 25, 100, and 150 mm) on chemical release rates. These release rates, influenced by the hole diameter, play a critical role in determining the extent of the vapor cloud's dispersion and the resulting consequences on human safety, infrastructure, and the environment. The primary objective of this research is to quantify how variations in release rates affect the severity of the explosion's impact over time, particularly with respect to the affected area and distance. The study employs ALOHA and MARPLOT simulation tools to model explosion scenarios at three chemical plants: IQOXE (Tarragona, Spain), Phillips Houston Chemical Complex (Texas, USA), and Formosa Plastics Corp (Texas, USA). At IQOXE, a 150 mm hole resulted in the largest release rate (317 kg/s), leading to a threat zone of 136,256 m² and a hazardous distance extending up to 393 meters, thus posing significant risks to neighbouring facilities. At the Phillips Houston Chemical Complex, a 17 kg/s ethylene release from a 150 mm hole affected the surrounding areas within a 288 m radius, whereas smaller leaks failed to trigger explosions due to lower release rates. Similarly, at Formosa Plastics, leaks from 100 mm and 150 mm vinyl chloride sources produced comparable impact areas, confined largely to the plant's immediate vicinity. Smaller leaks had minimal effects, highlighting the non-linear relationship between leak size and explosion consequences. The findings underscore the critical importance of understanding release rate dynamics for improving safety protocols and mitigating the risks associated with vapor cloud explosions in industrial settings.
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