Explosion fireball

A fireball then developed. Several ensuing explosions, fireballs, and BLEVEs destroyed the refinery almost completely, causing the deaths of seven people and injuries of ten. 

THE PHENOMENOLOGY OF HIGH EXPLOSIVE FIREBALLS FROM FIELDED SPECTROSCOPIC AND IMAGING SENSORS FOR EVENT... 

The heat of the explosion fireball oan oause thermal burns and start fires. 

Design of explosion suppression systems is clearly complex, since the effectiveness of an explosion suppression system is dependent on a large number of parameters. One Hypothesis of suppression system design identifies a limiting combustion wave adiabatic flame temperature, below which combustion reactions are not sustained. Suppression is thus attained, provided that sufficient thermal quenching results in depression of the combustion wave temperature below this critical value. This hypothesis identifies the need to deliver greater than a critical mass of suppressant into the enveloping fireball to effect suppression (see Fig. 26-43). 

Boiling liquid expanding vapour explosion follows failure of a pressurized eontainer of flaimnable liquid, e.g. LPG, or a sealed vessel eontaining volatile flammable liquids, under fire eonditions. Ignition results in a fireball and missiles. 

Figure 7.2 Diameter of fireball versus quantity of explosive...

During the test, hydrogen flow rate was raised to a maximum of approximately 55 kg/s (120 Ib/s). About 23 seconds into the experiment, a reduction in flow rate began. Three seconds later, the hydrogen exploded. Electrostatic discharges and mechanical sparks were proposed as probable ignition sources. The explosion was preceded by a fire observed at the nozzle shortly after flow rate reduction began. The fire developed into a fireball of modest luminosity, and an explosion followed immediately. 

At 5 45 A.M., a flash fire resulted. The vapor cloud is assumed to have penetrated houses, which were subsequently destroyed by internal explosions. A violent explosion, probably involving the BLEVE of several storage tanks, occurred 1 minute after the flash fire. It resulted in a fireball and the propulsion of one or two cylindrical tanks. Heat and fragments resulted in additional BLEVEs. 

At 2 20 A M., another explosion occurred, the BLEVE of sphere 407. Its fireball was less intense than the earlier one. The sphere s top section traveled 190 m (620 ft) and caused the destruction of a firewater tank and one of the plant s fire pumps. Other sections further damaged other units. The pressure relief valve of this sphere traveled 500 m (1600 ft). The damage from projectiles was much greater than that caused by the first sphere failure because they traveled farther and in more damaging directions. 

Accident scenarios leading to vapor cloud explosions, flash fires, and BLEVEs were described in the previous chapter. Blast effects are a characteristic feature of both vapor cloud explosions and BLEVEs. Fireballs and flash fires cause damage primarily from heat effects caused by thermal radiation. This chapter describes the basic concepts underlying these phenomena. 

Hasegawa, K., and Sato, K. 1977. Study on the fireball following steam explosion of n-pentane. Second International Symposium on Loss Prevention and Safety Promotion in the Process Industries, pp. 297-304. 

In the present context, the term BLEVE is used for any sudden loss of containment of a liquid above its normal boiling point at the moment of its failure. It can be accompanied by vessel fragmentation and, if a flammable liquid is involved, fireball, flash fire, or vapor cloud explosion. The vapor cloud explosion and flash fire may arise if container failure is not due to fire impingement. The calculation of effects from these kinds of vapor cloud explosions is treated in Sections 4.3.3 and 5.2. 

Although the experiments reported by Maurer et al. (1977) were performed for a completely different reason, namely, to study effects of vapor cloud explosions (see Section 6.4), fireballs were nevertheless generated. These experiments involved vessles of various sizes (0.226-1000 1) and containing propylene at 40 to 60 bar gauge pressure. The vessels were ruptured, and the released propylene was ignited after a preselected time lag. One of these tests, involving 452 kg of propylene, produced a fireball 45 m in diameter. 

Immediately after this blast, a fire originated at the west end of B Module and erupted into a fireball along the west face. The fire spread quickly to neighboring portions of the platform. Approximately 20 minutes later, a major explosion happened due to the rupture of the Tartan gas riser. This occurrence caused a massive and prolonged high pressure jet of flames that generated intense heat. At about 10 50 PM, another immense blast occurred that was believed to be a result of the rupture of the MCP-01 gas riser. Debris from this explosion was projected up to 800 m. away from the platform. Structural deterioration at the level below Module B had begun. This failure was accelerated by a series of additional explosions. One of these eruptions was caused by the fracture of the Claymore gas riser. Eventually, the vast majority of the platform collapsed. 

J. B, Gayle and J. W. Bransford, "Size and Duration of Fireballs from Propellant Explosions," NASA report TMX-53314, George C, Marsluill Space Flight Center, Hmitsville, AL, 1965,... 

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