Modeling a Boiling-Liquid, Expanding-Vapor Explosion Phenomenon with Application to Relief Device Design for Liquefied Ammonia Storage

Abstract

This paper addresses a fictitious accident scenario involving an ammonia storage tank in a refinery. Ammonia is used in a deNOx system. In a selective catalytic reduction environment, a refinery stack gas containing nitric oxide and nitrogen dioxide is decomposed into nitrogen and water vapor. In this study, a cylindrical ammonia tank is “bleved” (boiling-liquid, expanding-vapor explosion (BLEVE)) with an external fire. We developed a computer model in order to determine the thermal response of a horizontal ammonia tank involved in fire engulfment accidents. The assessment of the separation distance between tanks and protection measures such as water spray cooling were also discussed. Further, we examined the relief device design and studied the open-system thermal response as well as pressure response effects in the event of a BLEVE for the ammonia tank.

The boiling liquid expanding vapour explosion (BLEVE): Mechanism, consequence assessment, management

“…For a 54 m 3 tank holding 23 tonnes of LPG which underwent a BLEVE at Alma-Ata, Kazakhastan, in 1989, Shebeko et al [22] theorize that the tank would not have exploded if its safety value had a cross sectional area not less than 77 cm 2 and operating pressure not exceeding 1.6 MPa. Attempts to develop pressure relief devices specific to the substance stored as PLG have also been made, for example liquefied ammonia [114]. The authors have modeled thermal response of a horizontal ammonia tank severely engulfed in fire.…”

Cellular Automata‐Based Systematic Risk Analysis Approach for Emergency Response

“…The aggregated weighted risk in the residential areas A to J were mainly analyzed. The aggregated weighted risk can be calculated using Equation (13). Table I presents the information about the population density, and the total number of the population of each residential area.…”

“…Accident modeling is the foundation of risk analysis, so simulating the accident spreading accurately and rapidly is very important. Empirical formulas (10,11) or partial difference equations (PDEs) (12)(13)(14) are usually used to model accidents in risk analysis in previous studies. However, an empirical formula method is simple but not very accurate, while the PDE method is accurate but computation time consuming.…”

A simplified model to predict the thermal response of PLG and its influence on BLEVE

“…So a BLEVE is severely affected by the mass and the temperature of the loading. Many researchers have studied the mechanism of BLEVE [2][3][4][5][6][7][8][9][10][11].…”

“…Some models were also utilized to predict the thermal response of LPG. Chen and Lin [6] had presented thermal response models for worst-case scenarios of a horizontal ammonia tank with complete fire engulfment. Ciambelli et al [7] modeled the internal tank pressure of a tank truck transporting LPG in a highway tunnel when a BLEVE occurred.…”