Pipeline Rupture

[Danlxyz + 62]

 

How can you have a fire under water. Does the gas pipeline have oxygen in it?

Edited July 3, 2021 by Danlxyz
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[Eric Gagen + 713]

The gas is coming out and reaches surface, where it catches fire somehow, or more likely is purposely lit on fire, so that at least you know where it is, and that it’s burning instead of drifting around and causing an explosion somewhere else.  The gas is coming up out of the water so fast, and in such a large amount that the flames are sustained on top of the water.  There is no oxygen in the natural gas. 
 

in theory, If the water is shallow enough, and the volume of gas coming out is large enough it’s possible for the flamefront to travel below the normal water surface and create a sustained jet of flame directly from the sea floor to the surface, and it’s possible that happened here.  The original ignition point still had to be above the normal water level however.  The oxygen for a fire burning well under the normal water level like this comes partly from the fires own heat pulling cool air down into itself, and partly from the heat of the fire ‘cracking’ some of the water near it into hydrogen and oxygen.  This is a process that absorbs heat, and would usually put the fire out, but there is such a massive heat source from the gas that makes it to surface burning free atmospheric oxygen that it can continue to sustain itself.  
 

The volume of gas coming out of a pipeline like this is unthinkably large compared to most peoples experience.  Take a gas stove, and put one of the burners on at maximum level.  Then multiply by a thousand.  Now you are burning enough gas to be easily counted on an industrial scale.  This particular rupture was probably for a line carrying between 10 and 100 times as much gas as that, so take your stove burner (at maximum) and multiply by 10,000 or 100,000.  Also make sure the gas is coming out at about 1,000 times the pressure that it comes out of the stove, so that a thick dense column of compressed gas can come shooting out fast enough and dense enough to cut through a plank of wood.  Then set it on fire.  

Edited July 3, 2021 by Eric Gagen

[Danlxyz + 62]

Thanks, Eric.

I wonder what the guys in that drilling platform said when all that gas came shooting out next to them.

[Ward Smith + 6,615]

Video link

Edited July 3, 2021 by Ward Smith
Better link

[Eric Gagen + 713]

46 minutes ago, Danlxyz said:

Thanks, Eric.

I wonder what the guys in that drilling platform said when all that gas came shooting out next to them.

No words can describe it easily that’s a situation where you have to figure out what’s happening , and get immediate control or abandon location, or maybe even both (establish as much control as possible then abandon) 

you can only hope that the critical people responsible for making decisions and taking action keep their composure, because if they don’t it’s hopeless and the situation will get worse.

[Landon Ferguson + 14]

On 7/3/2021 at 3:46 PM, Danlxyz said:

Thanks, Eric.

I wonder what the guys in that drilling platform said when all that gas came shooting out next to them.

That's a production platform not drilling.

[Eric Gagen + 713]

22 hours ago, Landon Ferguson said:

That's a production platform not drilling.

I was trying to keep it simple.  Most folks don’t even know there is a difference much less what the difference is. 

[nsdp + 449]

On 7/5/2021 at 7:14 PM, Eric Gagen said:

I was trying to keep it simple.  Most folks don’t even know there is a difference much less what the difference is. 

I have looked at some of the Spanish language reports as the English language reports  are not very informative.   This is a satellite platform and the line is a NG/NGL gathering line 300mm id. "Ku Maloob Zaap is Pemex’s biggest crude oil producer, accounting for more than 40 percent of its nearly 1.7 million barrels of daily output."  This field produces  the Maya heavy crude mostly which is also 3.5 % sulfur (not H2S fortunately).  Texasgulf Sulphur used to  operate two Frasch process sulfur mines about 15km away.   If the sulfur concentration is high enough (after separating NGL/NG from the crude) it will replace oxygen as an oxidizer  which will produce mercaptains as a combustion product when burned under water. Apparently PEMEX closed the block valves and emptied the line with nitrogen. https://www.ntd.com/underwater-fire-erupted-in-the-gulf-of-mexico-from-gas-leak-extinguished-oil-company_637125.html

[Sebastian Meana + 278]

On 7/3/2021 at 1:07 PM, Danlxyz said:

 

How can you have a fire under water. Does the gas pipeline have oxygen in it?

1-Salt corrodes steel
2-It catches fire when it goes abovesea and encounters oxygen
3-the earth tectonic plates are always moving.

those are the reasons why most new oil and gas projects offshore rigs and FPSOs use flexible pipelines

[Eric Gagen + 713]

1 hour ago, Sebastian Meana said:

1-Salt corrodes steel
2-It catches fire when it goes abovesea and encounters oxygen
3-the earth tectonic plates are always moving.

those are the reasons why most new oil and gas projects offshore rigs and FPSOs use flexible pipelines

The new ones are actually flexible steel pipelines.  Sometimes there are a few short sections of other materials, but 99% of the length is steel.  With the right alloys and heat treatment steel can be extremely flexible.  It's one of the big advantages of steel for pipes. 

[Sebastian Meana + 278]

2 hours ago, Eric Gagen said:

The new ones are actually flexible steel pipelines.  Sometimes there are a few short sections of other materials, but 99% of the length is steel.  With the right alloys and heat treatment steel can be extremely flexible.  It's one of the big advantages of steel for pipes. 

Hmm, i guess i should investigate more the first stuff that cames to my mind when i hear flexible pipelines is this

[Eric Gagen + 713]

20 hours ago, Sebastian Meana said:

Hmm, i guess i should investigate more the first stuff that cames to my mind when i hear flexible pipelines is this

This is what you should be thinking of.  It's steel pipe (no fancy interior components or  layers or seals, or flexible links, just forged rolled welded steel) with an anti-corrosion coating on the outside.  This is how nearly all undersea pipelines have been done in the last 30 years or so.  What you have a picture of is temporary piping for specific services.  It is about 10,000 times to expensive to lay on the ocean floor and leave there, and also about 10,000 times more failure prone if you leave it in place for a few years.  You cannot take something with all those different layers and moveable parts and just leave it somewhere for 20-30 years and expect it to keep working.  it requires regular maintenance and repair, and then it's scrapped after a 3-4 years.  

Here is a quick article about how pipelines are actually set up:  https://oilmanmagazine.com/article/potential-failure-modes-and-considerations-for-reel-lay-method-of-installation/

Edited October 30, 2021 by Eric Gagen

[nsdp + 449]

On 10/29/2021 at 7:42 AM, Eric Gagen said:

The new ones are actually flexible steel pipelines.  Sometimes there are a few short sections of other materials, but 99% of the length is steel.  With the right alloys and heat treatment steel can be extremely flexible.  It's one of the big advantages of steel for pipes. 

Long ways from pipelaying barges in the early 80's. Although PLUTO for D-Day was a Reel Barge lay.

[nsdp + 449]

Is this like the old spiral wound  welded pipe  that became  so exciting if a weld failed.

[Eric Gagen + 713]

On 10/30/2021 at 11:07 PM, nsdp said:

Is this like the old spiral wound  welded pipe  that became  so exciting if a weld failed.

No.  It’s either rolled and seam welded, or extruded sections with butt welds.