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LNG Safe Pratices

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LNG Safe Pratices
Posted by SAMUEL C WALKER on Friday, September 18, 2020 10:52 AM

Perhaps the best way for LNG by rail will be for active sensors on the tank at all times. That way a problem will be addressed prompty and early avoiding a catastrophe. Otherwise, the tank will be a dumb tank car. Tank cars should be outfitted to be smart and confirm that the tanks car is fit. This might overcome serious concerns for LNG transport.

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Posted by Overmod on Friday, September 18, 2020 11:05 AM

SAMUEL C WALKER
This might overcome serious concerns for LNG transport.

There are already fewer serious concerns for rail LNG transport than for most other fuels.  This is particularly true with the advent of practical nanoinsulation materials and fabrication in the last half-decade or so.

Of course, cheap 'commodity' car tracking is now easier and orders of magnitude cheaper than what, say, Olin uses, and metadata transfer of a few things like boiloff rate becomes almost trivial to add to a tracking signal.  For a competent programmer, even something like using pager frequencies as a 'command' channel to request or even configure onboard sensing or control equipment is not difficult even if there is no good way to provide 'uplink' via unused bandwidth or channels in the radio or PTC architecture.

Note that in most cases a problem with onboard LNG condition monitoring could be pretty well handled with lights, whistles, and some kind of transponder of the general "I've fallen and I can't get up" sort of action.  Even if something knocked or shot the boiloff relief valve off one of these cars, the atmosphere will not support critical-mixture explosion over the pool even if the blanket gas is exhausted.  A good self-contained indicator 'suite' would be valuable to first responders assessing any sort of severe wreck, certainly much more than some encoded datastream using what are likely to be fragile and exposed antennas for transmission.

No need for hysterical safety measures at all ... 

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Posted by Overmod on Friday, September 18, 2020 11:07 AM

SAMUEL C WALKER
This might overcome serious concerns for LNG transport.

There are already fewer serious concerns for rail LNG transport than for most other fuels.  This is particularly true with the advent of practical nanoinsulation materials and fabrication in the last half-decade or so.

Of course, cheap 'commodity' car tracking is now easier and orders of magnitude cheaper than what, say, Olin uses, and metadata transfer of a few things like boiloff rate becomes almost trivial to add to a tracking signal.  For a competent programmer, even something like using pager frequencies as a 'command' channel to request or even configure onboard sensing or control equipment is not difficult even if there is no good way to provide 'uplink' via unused bandwidth or channels in the radio or PTC architecture.

Note that in most cases a problem with onboard LNG condition monitoring could be pretty well handled with lights, whistles, and some kind of transponder of the general "I've fallen and I can't get up" sort of action.  Even if something knocked or shot the boiloff relief valve off one of these cars, the atmosphere will not support critical-mixture explosion over the pool even if the blanket gas is exhausted.  A good self-contained indicator 'suite' would be valuable to first responders assessing any sort of severe wreck, certainly much more than some encoded datastream using what are likely to be fragile and exposed antennas for transmission.

No need for hysterical safety measures at all ... although I would not object to FRA or PHMSA requiring some sort of smart monitoring for all 'hazmat' cars.

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Posted by tree68 on Friday, September 18, 2020 11:20 AM

After the initial onslaught of LPG incidents (Oneonta, Kingman, et al),  there haven't been many major LPG problems.  The fixes instituted following those incidents have been quite effective.

The issue is that the behavior of the cars following a derailment is only so predictable.  No matter what safeguards one puts in place, chance will find a way to defeat them.

The idea of individually monitoring cars is not too outlandish - the technology certainly exists to do so in a number of ways.  

But we must realize that LPG tends to be seasonal - many of the cars spend half the year in storage on unused backtracks.  Any sort of active monitoring (like is used for reefers) must take that into account.  For that matter, providing power for such monitoring must be considered as well.

LarryWhistling
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Posted by Overmod on Friday, September 18, 2020 11:26 AM

tree68
After the initial onslaught of LPG incidents (Oneonta, Kingman, et al),  there haven't been many major LPG problems.

That has no relevance in this thread whatsoever.

You might as well discuss undegassed Bakken crude in a discussion of transporting Bunker C or residual in tank cars.

LPG is only 'liquefied' under pressure, and in consequence among many other things is a BLEVE hazard.  LNG cannot be that under any circumstances achievable even in railroad accidents, as the amount of pressure applied to sufficient volume over time to heat the liquid out of cryo is orders of magnitude too great while assuming structural integrity orders of magnitude higher than achievable.

In my experience the chief risk in LNG transport is the creation of an established pool fire.  As you can see from videos investigating these (some of which have been posted in other threads here) these are relatively slow to develop and, while very hot, not that difficult to extinguish.

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Posted by tree68 on Friday, September 18, 2020 11:36 AM

Overmod
That has no relevance in this thread whatsoever.

My bad - I misread LNG as LPG.  You are absolutely correct.

LarryWhistling
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Posted by Overmod on Friday, September 18, 2020 11:39 AM

Don't think I was castigating you in person either -- of all the people here you're likely the most qualified to assess and deal with emergency situations involving these things.  I wanted to establish, perhaps more forcefully because the statement came from such an expert, that the two materials behave very differently in accidents, before folks like the OP 'concluded' wrongly that LNG is a severe transport hazard.

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Posted by tree68 on Friday, September 18, 2020 11:42 AM

Overmod

Don't think I was castigating you in person either -- of all the people here you're likely the most qualified to assess and deal with emergency situations involving these things.  I wanted to establish, perhaps more forcefully because the statement came from such an expert, that the two materials behave very differently in accidents, before folks like the OP 'concluded' wrongly that LNG is a severe transport hazard.

NP - your correction was appropriate and your post was informative.

LarryWhistling
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Posted by Erik_Mag on Friday, September 18, 2020 10:27 PM

While I'm sure that Larry (Tree) and OM know, the difference between LNG and LPG is that the critical temperature for propane is almost 200F, the critical temperature for natural gas is colder than -150F. What this means is that propane will liquify under pressure at any ambient temperature on the surface of the earth with the exception of geothermal hot spots, but there is no place on earth that gets cold enough for methane to turn liquid.

One of my thoughts for LNG tank cars is to have a cryocooler powered by methane vented from the tank. The cryocooling would reduce the amount of vented methane and the engine powering the cryocooler would burn off what methane was vented. Not sure how practical this would be....

The thought of an LNG tank car caught in a fire does concern me, but not as much as a hopper car loaded with ammonium nitrate caught in a major fire.

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Posted by SD70Dude on Friday, September 18, 2020 11:16 PM

I switch all this stuff on a daily basis (well, not LNG, not yet anyway).

Anhydrous ammonia and liquid/compressed chlorine scare me more than anything else. 

CN has been running unit trains of LPG (propane) for a couple years now, and for a long time we've had a daily train from the Edmonton area to Winnipeg that is primarily composed of ammonia, LPG and other 'goodies'. 

Greetings from Alberta

-an Articulate Malcontent

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Posted by Shadow the Cats owner on Sunday, September 20, 2020 8:44 PM

I worry more about my drivers in traffic hauling acid and chlorine than anything that is hauling LNG.  The NIMBY's and Bananas are just screaming at stuff because they are moronic idiots looking for their next bogeyman to be scared of.  

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Posted by tree68 on Sunday, September 20, 2020 8:55 PM

Erik_Mag
...but there is no place on earth that gets cold enough for methane to turn liquid.

Although some mornings in late January in the north country sure feel like it...  Smile, Wink & Grin

I believe there is a door-to-door food sales company that uses LNG to power their trucks...  Not that the public realizes that...

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Posted by ChuckCobleigh on Sunday, September 20, 2020 11:55 PM

SD70Dude
Anhydrous ammonia and liquid/compressed chlorine scare me more than anything else. 

As well they should. Nasty stuff if they get loose in quantity.

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Posted by Erik_Mag on Monday, September 21, 2020 12:06 AM

tree68

 Although some mornings in late January in the north country sure feel like it...  Smile, Wink & Grin

Cold enough that a LNG bath sounds warm?

Reminds me of a scene in a comic book with people in a desert:

"Man that sun is hot!"

"That's the moon. When the sun comes up you will feel like cooling off in a blast furnace."

I believe there is a door-to-door food sales company that uses LNG to power their trucks...  Not that the public realizes that...

Interesting. I've seen LN2 dewars that would make reasonable LNG tank (LN2 is colder than LNG). With the ignition temperature of methane running just above 1,000F, and the rapid dispersal of LNG vapors, it doesn't sound like much of a safety problem. I would expect methane to be a very clean burning fuel - spark plug and oil lifetime should be pretty long.

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Posted by tree68 on Monday, September 21, 2020 12:27 AM

Erik_Mag
With the ignition temperature of methane running just above 1,000F, and the rapid dispersal of LNG vapors, it doesn't sound like much of a safety problem.

It's Schwan's, which also uses LP.

LarryWhistling
Resident Microferroequinologist (at least at my house) 
Everyone goes home; Safety begins with you
My Opinion. Standard Disclaimers Apply. No Expiration Date
Come ride the rails with me!
There's one thing about humility - the moment you think you've got it, you've lost it...

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