History 2 Pipe Rupture Leads to an LPG Tank BLEVE

Case History 2 Pipe Rupture Leads to an LPG Tank BLEVE 

On November 19, 1984, a major fire and a series of catastrophic explosions occurred at the government owned and operated PEMEX LPG Terminal at San Juan Ixhuatepec, Mexico City. 

Three refineries supplied the facility with LPG on a daily basis. The plant was being filled from a refinery 248 miles (400 km) away. Two large spheres and 48 cylindrical vessels were filled to 90% and 4 smaller spheres to 50%. 

A drop in pressure was noticed in the control room and also at a pipeline pumping station. An 8-inch (20-cm) pipe between a sphere and a series of horizontal bullets had ruptured. Unfortunately, the operators could not identify the cause of the pressure drop. The release of LPG continued for —5-10 minutes when the gas cloud, estimated at 656 ft x 492 ft x 6.6 ft (200 m x 150 m x 2 m) high, drifted to a flare stack. It ignited, causing violent ground shock. 

Workers at the plant tried to deal with the escaping LPG and the emergency response, taking various actions. At a late stage, an emergency shutdown was initiated. About fifteen minutes after the initial release, the first BLEVE occurred. For the next hour and a half there followed a series of BLEVEs as the LPG vessels violently exploded. LPG was said to rain down and surfaces cov- 

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