BLEVE=Huge Pucker Factor

[LFDAO10]

Interesting video on CNN

http://www.cnn.com/video/#/video/us/...n.drymedia.com

Guess that tank just wasn't being cooled enough. Amazing how that large tank just takes off like a rocket. Hopefully everyone made it out ok.

[mcaldwell]

Wow, that came outta nowhere.

I have to say, I'm out of my depth on these refinery incidents, but that water application looked pretty ineffective. Three streams on the open top (which wasn't going anywhere), with two of them very broken before they even came close, and no apparent cooling of the vessel or it's neighbours. I would like to see other angles though, tough to judge by one crappy handicam viewpoint.

Definitely hope everyone was ok.

[FWDbuff]

BLAST LEVELING EVERYTHING VERY EFFECTIVELY
BIG LOUD EXPLOSION VERY EXCITING


I'm not too terribly sure that this was a true BLEVE.......Although we only had one perspective from this camera angle, there just didn't seem to be enough radiant heat to cause a BLEVE......I'm thinking this was a case of a pressurized vessel that had a failure of some piping.....watch the video....In the beginning, you see a rupture, and a pressurized blast of flame exiting the top of the tank. This happens for 1-2 seconds. I'm thinking the flames followed the vapors of the stored materials down through the rupture, and ignited the liquid within, causing an explosion. The BLEVE's I have seen on video have always occurred in tanks with no failures whatsoever.....and are usually very violent and without warning. I am thinking that if a true BLEVE occurred here, the guys on that apparatus, and the apparatus, would not be here anymore.

[FWDbuff]

I just watched it again 3 more times....I stand by my assessment above, with the following disclaimer- I am NOT a tank expert nor have I ever seen a true BLEVE other than on videos. What happened here just doesn't fit the textbook definition of a BLEVE in my eyes. I defer to other experts. Just my opinion. This has the makings of a good discussion for everyone. Let's not let it get trashy, ok?

EDIT: Immediately after posting this, I went to my email to send the link to someone I know who is an expert in these matters, and my inbox contained a message from TSL....which is as follows:

"Lamesa and Andrews (Texas) Firefighters were operating at a tank fire last evening. They had water flowing, attempting to cool. At about 2 hours into it, a relief valve blew ...but then the tank and nearby tanks exploded and took off. The photographer was 200 yards away and a piece of 4" pipe about a foot and a half long with a cutoff valve on it came through the air in a high enough arc that it cleared the power lines next to him in impact the front of his vehicle, causing extensive damage."

[BryanLoader]

I'd agree it wouldn't have been a BLEVE, but I would guess the reporter and a few of those nearby would have had a BLESOP. ( Brown liquid explosion seat of pants)

[doughesson]

I'd agree it wouldn't have been a BLEVE, but I would guess the reporter and a few of those nearby would have had a BLESOP. ( Brown liquid explosion seat of pants)

Some folks might call it one if they were there.Maybe they also call a "small scale conflict" a "large scale war" when the bullets fly in there direction.But I could be mixing metaphors again.
I'm told that using water on a refinery tank can result in some of the water going to the bottom where it absorbs enough heat to boil up,and in expanding,lift the petroleum product up and out of the tank where it spreads and ignites.
That doesn't sound too good to me.

[txgp17]

That isn't a BLEVE. Petroleum (Gas/Diesel/Kerosene) is not stored under pressure like LPG. When that tank ruptures, you can clearly see large amounts of liquid surge from the tank. From all the data I seen & read on BLEVE's, that doesn't happen. Plus there is a lack of an obvious "Expanding Vapor" in that incident, which would be especially visible at night, contrasted against a dark horizon.

Clearly, there's pressure involved, but compare that with some other BLEVE vids on youtube.

I can't guess the GPM they were throwing on it, but if they were using residential/commercial equipment for a industrial fire, then they brought the wrong weapons to the fight. You know the old saying, "Don't bring a knife to a gunfight."

My Dept has large oil storage in the district, 2nd largest on the East Coast.

We have 10,000' of 7¼" hose to supply water, pushed from a 6,000 GPM pump driven by a Caterpillar 3412.

[nmfire]

I wanna know where the tank landed after it took off.

[BryanLoader]

That isn't a BLEVE. Petroleum (Gas/Diesel/Kerosene) is not stored under pressure like LPG. When that tank ruptures, you can clearly see large amounts of liquid surge from the tank. From all the data I seen & read on BLEVE's, that doesn't happen. Plus there is a lack of an obvious "Expanding Vapor" in that incident, which would be especially visible at night, contrasted against a dark horizon.

Clearly, there's pressure involved, but compare that with some other BLEVE vids on youtube.

I can't guess the GPM they were throwing on it, but if they were using residential/commercial equipment for a industrial fire, then they brought the wrong weapons to the fight. You know the old saying, "Don't bring a knife to a gunfight."

My Dept has large oil storage in the district, 2nd largest on the East Coast.

We have 10,000' of 7¼" hose to supply water, pushed from a 6,000 GPM pump driven by a Caterpillar 3412.

Technically you can have a BLEVE on a gas or diesel storage tank if flame impingement reaches above level of liquid. Usually does not have the pressure release of a LPG/LNG/Condensate tank, more of a column of flame following the lid upward. TXGP is totally correct in the necessity for extremely large volumes of water for cooling.

[txgp17]

Technically you can have a BLEVE on a gas or diesel storage tank if flame impingement reaches above level of liquid.

Correct, but it usually involves pressurizing the liquid to increase it vapor pressure, and then heating it beyond it's boiling temperature (at atmospheric pressure), then when the tank ruptures, and the pressure is relieved, most everything instantly vaporizes and then burns once it finds oxygen.

Very few petro tanks can hold that amount of pressure.

[AlphaSvn]

We have 10,000' of 7¼" hose to supply water, pushed from a 6,000 GPM pump driven by a Caterpillar 3412.

What kind of water supply are you using to supply 6,000 GPM Pump?

We have several of these tanks in neighboring districts, and I don't believe we have anything like the above to put water on it.

[txgp17]

What kind of water supply are you using to supply 6,000 GPM Pump?

Pumps from a draft. The storage facility has a large catch basin fed by rain water. It uses five or six 6" intakes.

For times when we can't find a drafting site, we have some special manifolds installed, called "ring main manifolds". Here's another link showing additional designs.

Also don't forget, a 1,500 GPM pump can flow 2,300 if you use multiple 6" intakes. Here's an example.

[BryanLoader]

Correct, but it usually involves pressurizing the liquid to increase it vapor pressure, and then heating it beyond it's boiling temperature (at atmospheric pressure), then when the tank ruptures, and the pressure is relieved, most everything instantly vaporizes and then burns once it finds oxygen.

Very few petro tanks can hold that amount of pressure.

Very true. In this case, I would class it as a flammable liquid/gas explosion. Bet there still were some lads with brown underwear especially bystanders.

[FWDbuff]

Here is the reply I got back from a very close friend who has lot of knowledge of this stuff....He has a bunch of initials after his name, including P.E., CSP, FSFPE.....(means he is a lot smarter than me....lol....)

"It is a rapid overpressure of the vessel. A BLEVE results from boiling liquid and expanding vapor - typically from a compressed liquified gas. However, BLEVE's can occur with other materials including flammable/combustible liquids. From the shape of the tank, it would appear this is a liquid not a gas, but hard to say. The relief valve relieving rapidly is a sign of overpressurizing the vessel, and the ignition of the material coming from the relief valve indicates it is flammable, as does the ignition of the product once the tank fails. I would assume the failure is due to heating, which would essentially make it a BLEVE, but need a bit more information. I assume the Chemical Safety Board (CSB) will investigate this one as it has been on a number of news channels. Parts of the piping hit the cameraman's car."

[RspctFrmCalgary]

I just finished watching a slow-mo version of the video (on IACOJ) - what an incredible sight! It's truly amazing there were no injuries.

[robertr2m]

I'm told that using water on a refinery tank can result in some of the water going to the bottom where it absorbs enough heat to boil up,and in expanding,lift the petroleum product up and out of the tank where it spreads and ignites.
That doesn't sound too good to me.

Heard this called a roll over or boil over. Saw it in person at a fule tank fire. Very impressive. The water hits the liquid, sinks to the bottom, reaches boiling point and becomes lighter than the fuel. As it goes back out. it takes fuel with it and the resulting roll over is very impressive.

Be safe, R2

[nmfire]

I still wanna know where the tank went. I lifted off and I never saw it come back down.

http://www.youtube.com/watch?v=DECyAxDk88U

[Dickey]

I still wanna know where the tank went. I lifted off and I never saw it come back down.

http://www.youtube.com/watch?v=DECyAxDk88U

From this video, I think you can see it in the foreground between the camera and the fire trucks, slightly to the left of center screen. Looks like it laying there steaming.

I also agree from looking at this it doesn't seem to be a BLEVE. In a "normal" BLEVE, the relief valve blows for a long period of time I would think right?

I have only experienced one BLEVE, or I guess we stopped it from getting to that point. A gasoline truck was involved in a crash with a fire. The car that struck it hit the front of the trailer and the trailer was flame impinged. Just 2 min after we arrived on scene the relief valve went off. We cooled the tank down right away and it stopped, then we put the car out. Could have been bad but we took care of the problem. It just seems to me the pressure relief valve would go longer, maybe not, I'm certainly not an expert.

I am sure glad no one got hurt, except a bunch of underpants of course!

[FWDbuff]

I also agree from looking at this it doesn't seem to be a BLEVE. In a "normal" BLEVE, the relief valve blows for a long period of time I would think right?

Jason, in a normal BLEVE event, there is no relief at all, that is why they are so violent. The off-gassing here (which ignited) is what first led me to believe that it was not a BLEVE.

[fireman4949]

Jason, in a normal BLEVE event, there is no relief at all, that is why they are so violent. The off-gassing here (which ignited) is what first led me to believe that it was not a BLEVE.

The relief valve could not keep up. The pressure was rising faster than it could vent.

IMHO, the boil-over theory is somewhat debunked in this instance as the venting if the vessel prior to failure would indicate that it was sealed, thus virtually eliminating water from the fire streams from entering the tank prior to failure.


Boil-over can occur when the temperature of a product (with a specific gravity of < 1) exceeds 212 degrees F and water is either already inside the container, or it is introduced after the heating occurs.
That's exactly what happens when someone throws water into a pan of burning grease on the stove. The water sinks, flash-boils and violently pushes the hot grease out of the pan. What was a small, contained fire now involves much of the kitchen and most likely much would-be firefighter as well.