Amuay UCVE

Amuay UCVE EventAug 25 2012 (Saturday) around 1:10 AM Disclaimer: RMG has developed the following material based on detailed analysis of information freely available on the net, our data bases, and from our industry contacts. We believe that an accurate event simulation and fact sheet has been developed, describing to the best of our knowledge the facts and consequences without warranties or judgments of any kind

In Amuay olefins are produced inthe cat cracking and in the coking operations

Olefins are used to produce alkylate, a motor gasoline component for octane improvement

Olefins are stored in spherical tanks due to its high vapor pressure and low boiling point

If this compound is released to the atmosphere, a vapor cloud will form This cloud mass will be about 50% heavier than air Once released, it will flow in the ground like a “river of fog”

Insiders reported that a olefins pump wasleaking…a pump seal failure perhaps?

Olefins pumpleak not fixed, last for days In Amuay the strong prevailing trade winds blow there most of the year These are a key design and operational factor

Olefins pumpleak not fixed, last for days Randomly, during August and September, and before a downpour prevalent winds may slow, sometimes change direction, from its regular eastward direction

Olefins pumpleak not fixed, last for days In the preceding days, atmospheric conditions caused showers in the area, the wind to erratically slow and change direction

Olefins pumpleak not fixed, last for days An operational decision seems to have been made to maintain the equipment in operation and keep the production on, relying on the wind to disperse the leaked vapors. Those, in concentrations below 2% in weight relative to air (LEL), are not flammable Click to continue

Leaksource The day before leaking vapor had reached the facility perimeter Amounts exceeding the allowable LEL (explosivity) were detected in the environment On Friday, a neighboring lube oil manufacturing plant had to be evacuated due to poor air quality

Leaksource Weather situation seems to improve later on the day. A team of workers at the Lube oil manufacturing plant return, and tries to catch up with production on Friday late night

About Friday midnight Leak The wind slows.source The now stillness does nothing to disperse the olefin vapors, which now begin to accumulate In a tragic coincidence of events, the leak suddenly becomes much larger

Leaksource

Low points/ path Leaksource Low points/ path

Leaksource

National Guards live here with their families Leaksource One worker is on the pedestrian overpass, walks away, leaving the area

One vehicle southbound approaches the vapor cloud Leaksource One worker is on the pedestrian overpass, walks away, leaving the area Lube oil plant team is still at work

Likely the car ignites the cloud here. The explosion force pushes it towards the opposite curb as seen in the attached pic Leaksource, nowignited, can be seen in the nextphotographs The worker on the pedestrian overpass dies Many people, houses are affected by the strong shock Five lube oil plant workers Many people, houses are perish while still at work affected by the strong shock

Olefinspump site

House damage pic 1 Business damage pic 3 Overpass damage pic 2 Business damage pic 4Lube oil plant damages pic 5 Lube oil plant damages pic 6

The operational decision to maintain the equipment inoperation and depend on the wind to to disperse the leaked vapors was a tragically poor one Fifty one lives lost so far and many more badly burned…

"I am living miracle.. it was not my time", said Edino Rafael Muñoz Lambertino(35), a man of Libertad de Barinas, survivor of the blast, who was held imprisonedthat night in the 44 National Guard depot located next to the Amuay Refinery. Afterbeing arrested on allegedly “soliciting” charges, he was to be released next day. “Whywere you not sleeping then?... He was talking with the national guards. "We were thentelling tales and the next day they were dead". He said that about 1 am on Saturday,they began to leave the facility since “the smoke was thick”. "Lets go there, need tomake several „rounds‟, the guards told us." Edino was led to the first jeep with 7guards. The jeep stutter half way, and when they tried restarting the vehicle, there wasan explosion. "It seems that it had lifted". "My mind was blank, like a dream, anightmare". Edino jump the car and ran down the street until a corner where stop torest. “When I look over there it came as a wave of fire, I laid down and prayed." "It wentover and then returned again." After that flash, Edino looked back at the jeep: it wasburning with all its passengers as well as another vehicle with military guards and alady with a 5-month-old girl. "All died. I saw them the next day in the newspaper“. “It isstrange that they stay put and did not run away." Scared, Edino resumed his escapeand met a family who were evacuating. "Lord, help me that I can barely walk", yelledEdino to them, who then took him to the hospital. "I had glass fragments in my skin.“On Saturday night, Edino had asked the guards why the strong smell of gas. "Theguards said that these are valves that open at times and that it was “normal." "Thats to“regulate” the tanks". But the atypical event of that day was that the gas beganspreading across the street "as fog", according to him… Link: http://www.ultimasnoticias.com.ve/Noticias/Actualidad/Sucesos/Testimonio-en-Amuay---Estoy-vivo-de-milagro--no-me.aspx

Unconfined Vapor Cloud Explosion UVCE

The results seen in the prior pictures suggest a gas phase explosion event,which generated a large overpressure without the presence of confining walls.This is referred to as Unconfined Vapor Cloud Explosion (UVCE).When a flame travels through the unconfined gas cloud with high velocity, thegas/air mixture ahead of the flame is unable to move away quickly enough toallow free expansion of the combustion products formed by the flame. As aresult pressure wave is formed ahead of the flame front with the destructiveforces seen. Edino was a lucky witness to this.The presence of obstacles (called congestion, observed where buildings maybe in the path) within the flow field of the gas cloud produces turbulence whichenhances the burning velocity, accelerates the production of combustionproducts and increases the flame speed. The higher the velocity of the flame,the higher the pressure generated ahead of it. If very high flame speeds areproduced, a Transition from Deflagration to Detonation (DDT) can occur.A detonation involves a very high pressure shock wave that further auto-ignitesthe gas/air mixture. The combustion of this mixture then provides the energy tosustain the shock wave, which may extend further than the vapor cloud. As aresult, a detonation is self-sustaining as long as the concentration of gas iswithin certain limits. This can be observed in the effects caused on the mostlybrick and concrete buildings, which even outside of the cloud, can be seenbadly damaged, on support of our modeling of the vapor cloud boundaries.

Update: More detailed aerial pictures, later available, tend to confirm the modeling results. Fromthese, it can be observed a clear delineation resulting from high temperature gradients (as seenin burned vegetation) which results to be different from the shock wave front effects, which ismostly observed by the affected structures and how these are geographically distributed. Amore detailed simulation of dynamic type can be derived from these results.

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Amuay UCVE

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