Paul_D_North_Jr The current (Jan. 2015) issue of Trains - in the Florida East Coast article, by Fred Frailey - says that all of its locos (all will be new GE's by the end of 2014) will be powered by a 80% LNG - 20% diesel mix starting next April, and then converting the rest of the fleet. A specially built 10,000 gal. cryogenic tank car/ tender will be used, and the FRA "gave the railroad the go-ahead to continue its work on LNG". See page 46, cols. 1 and 2, under the heading "A BIG POWER GRAB". - Paul North.
The current (Jan. 2015) issue of Trains - in the Florida East Coast article, by Fred Frailey - says that all of its locos (all will be new GE's by the end of 2014) will be powered by a 80% LNG - 20% diesel mix starting next April, and then converting the rest of the fleet. A specially built 10,000 gal. cryogenic tank car/ tender will be used, and the FRA "gave the railroad the go-ahead to continue its work on LNG". See page 46, cols. 1 and 2, under the heading "A BIG POWER GRAB".
- Paul North.
FEC is not replacing it's entire locomotive fleet;it will still roster a sizable number of older EMD units (SD40-2/GP38-2/GP40-2 models) for switching and local service. The railroad will be selling its small fleet of SD70M-2'S on delivery of the new Ge's,however....
"I Often Dream of Trains"-From the Album of the Same Name by Robyn Hitchcock
EuclidIs it accurate to conclude the following? 1) No LNG has ever been shipped by rail in the U.S. 2) No LNG tank car has ever been approved and manufactured for LNG transport in the U.S. 3) No LNG tank car federal specifications have ever been developed for the U.S. 4) No LNG can be shipped by rail in the U.S. in a tank car that is not approved by federal specifications.
A great many of the answers might be derived from one of the actual waivers that have been granted (in this case for movement of 'tender cars' to Pueblo for testing).
I have questions regarding this quote from the article linked to the OP:
“Transporting gas by rail, most likely as cryogenic liquefied natural gas (LNG), faces obstacles. The technology is in its infancy, and so far no tank car is permitted to carry the fuel on U.S. rails.
More-volatile liquids like ethylene and propane already travel on the rails in growing volumes. But as concerns about the safety of crude by rail intensify, regulators are exercising extreme caution with uncertified fuels like LNG, said executives involved in developing the technology.
Regulators and railroads last year established a task force to establish standards for LNG rail cars. A spokesman for the U.S. Federal Railroad Administration said there was no specified deadline for drafting actual rules.
Building these tank cars would be "a natural progression into hauling LNG, similar to what we do with crude oil," said Ken Webster, chief accounting officer at Chart Industries Inc.
Outside North America, steps have already been taken. Chart is developing an LNG tank car in Germany in a joint venture with Hamburg-based manufacturer VTG Aktiengesellschaft.”
Is it accurate to conclude the following?
1) No LNG has ever been shipped by rail in the U.S.
2) No LNG tank car has ever been approved and manufactured for LNG transport in the U.S.
3) No LNG tank car federal specifications have ever been developed for the U.S.
4) No LNH can be shipped by rail in the U.S. in a tank car that is not approved by federal specifications.
Yes, LNG-by-rail would lose in head to head compition with a gas pipeline. Earlier in this thread it was pointed out that the main customer would be in places like the Bakken, which is still underserved by pipelines. Gas produced along with the oil would have to be flared for lack of gas lines. Sometimes O&G regulators will shut in such a well to prevent waste. The oil producers might ship LNG at low margin just to be able to produce the oil.
EuclidI get the impression that the industry feels that talking about a new market for LNG would further damage their position with oil by rail.
While that may certainly be true, I think that even a cursory examination of LNG-by-rail fails some very fundamental economic smell tests.
LNG is a comparatively low-energy fuel, that would need to be transported in specially-built and expensive cryogenic tankers that could be used for few alternative purposes. You would need steady lanes between source liquefaction plants and ... whoever would be using LNG in preference to regular pipeline-delivered gas, or CNG from cheap compressor stations; I don't know what aside from locomotive fuel service would meet such a set of requirements. And the profit (as with unit coal trains) would need to involve empty backhaul, both in terms of tare and the time the units are out of revenue-haul movement.
Perhaps a large-scale export of LNG to foreign markets would provide the 'magic' combination of factors that would make LNG unit trains practical. But here, too, I think you'll wait a long time to find someone stupid enough to gamble all the capital required for the fleet of cars on such an uncertain means of generating a return. The fact that people think LNG explodes, and the fact that it has an easily-located history of disaster, puts additional layers of icing on the cake. Even if we assume industry PR to get the word out on relative LNG safety ... watch for it to become the next bugbear of the no-nukes folks. Who (of the people relying for a paycheck on that area of the energy industry) has the time to waste 'educating the ignorant' when there is so little gold in the pot even if they succeed?
Public perception has not stopped the crude oil trains, so I don't see why it would stop LNG-by-rail. LNG appears to be safer than propane, which is hauled all the time. If a practical LNG tank car is developed, and the LNG shippers present it for carrage, the common carrier RRs have to accept it.
Deggesty Euclid The article says that there is a good market for LNG moved by rail, but it places great emphasis on a public perception problem presented as a showstopper. Interestingly, the article offers little hope of overcoming this public perception problem. The public perception problem for LNG is simply that the public perceives oil trains as being unsafe, and they will naturally apply the same reasoning to LNG trains. One might argue that the oil train problem has been exaggerated and sold to the public. If so, to the extent that the oil train safety problem is false, that falsity would extend to LNG trains. But even if the oil problem has been exaggerated, from what has been said here, the safety risk of hauling LNG is much less than the risk of hauling Bakken oil. We are told that LNG will not offer an explosion hazard, and that its fire hazard is apparently much lower than that of the oil. So the question is whether the industry is simply going to cower away from the promising LNG market because they refuse to fight the public relations battle. From the tone of the article, the answer is yes. In other words, the public is being sold a bill of goods by people who apparently do not want to really learn the facts of the matter..
Euclid The article says that there is a good market for LNG moved by rail, but it places great emphasis on a public perception problem presented as a showstopper. Interestingly, the article offers little hope of overcoming this public perception problem. The public perception problem for LNG is simply that the public perceives oil trains as being unsafe, and they will naturally apply the same reasoning to LNG trains. One might argue that the oil train problem has been exaggerated and sold to the public. If so, to the extent that the oil train safety problem is false, that falsity would extend to LNG trains. But even if the oil problem has been exaggerated, from what has been said here, the safety risk of hauling LNG is much less than the risk of hauling Bakken oil. We are told that LNG will not offer an explosion hazard, and that its fire hazard is apparently much lower than that of the oil. So the question is whether the industry is simply going to cower away from the promising LNG market because they refuse to fight the public relations battle. From the tone of the article, the answer is yes.
In other words, the public is being sold a bill of goods by people who apparently do not want to really learn the facts of the matter..
Deggesty In other words, the public is being sold a bill of goods by people who apparently do not want to really learn the facts of the matter..
Facts? Since when does the public want to be confused by facts.
Never too old to have a happy childhood!
Johnny
The whole discussion of this thread comes down to environmental and risk management. Gas is flared at new oil fields (or the wells are shut in) because gas pipelines have not reached there. Besides wasting the resource, burning the gas creates greenhouse gases. Venting the gas would be even worse, since methane, as a greenhouse gas, is an order of magnatude worse than CO2. Formerly when more gas was needed, it was imported by LNG tanker. Now it could be hauled by rail car.
WizlishI consider it very likely that some of the effects of the 1944 Cleveland accident were produced by this mechanism.
The incident in Cleveland was significant if for no other reason than the sheer volume of LNG involved. The tank that initially failed (which failure led to the explosion) had a capacity of 100,000,000 cubic feet of LNG. Factoring in the 640:1 difference between gaseous and compressed LNG, and assuming that 100M CuFt figure to be gaseous, not compressed, that's about a 160,000 cubic foot tank, equal to around a 1.25M gallon water tank.
Liquid LNG entering the sewer system obviously began its expansion, which forced the now gaseous gas back into homes, causing much of the damage there.
Pretty much any flammable substance, given the right circumstances, will burn very quickly and violently (ie, explode). If that explosion occurs in a confined space (ie, sewers) mayhem will follow, as it did. One responding fire truck found itself in a crater as a sewer exploded under it.
Larry 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...
erikemWhat impressed me was the guy walking up to the simulated spill to ignite the gas plume and his calmly walking away after ignition
Precisely.
Wizlish In particular, watch what happens starting around 2:55 regarding the behavior at ignition. Rather eye-opening for the proponents of grand explosive disaster.
In particular, watch what happens starting around 2:55 regarding the behavior at ignition. Rather eye-opening for the proponents of grand explosive disaster.
One more thing: See this video:
https://www.youtube.com/watch?v=h-EY82cVKuA
This describes PHYSICAL 'explosions' (similar to steam explosions in sulfuric acid, hot metal or lava) that occur when a comparatively large volume of cryomethane is quickly dumped into water. I consider it very likely that some of the effects of the 1944 Cleveland accident were produced by this mechanism.
Note, however, that this is not a 'detonation' in the combustion sense, and if you watch the sequence at the end of the video you will see that even ignition of the developing 'physical explosion' cloud only produces a deflagration and comparatively tiny pressure increase.
As a further illustration of LNG spill behavior, note the following video:
https://www.youtube.com/watch?v=k-JZU7wSgl8
EuclidI suspect that the potential for explosion magnitude in an LNG fire involving leaking tank cars would be much greater than in a Bakken oil fire involving leaking tank cars.” I was not referring to the likelihood of an explosion occurring. I was referring to size of the explosion if one does occur.
I think a better question would be the size (and characteristics) of the fire when one occurs. This is probably the chief concern in a LNG accident. If the intensity of a LNG pool fire is substantially greater than a gasoline pool fire, I'd expect it to be greater still than a crude-oil pool fire ... I'd expect it to burn out sooner than a crude-oil fire, though.
A secondary question would be whether the higher pool-fire intensity would augment secondary damage to other cars, or chemicals contained in other cars, involved in an accident or derailment.
For there to be an 'explosion magnitude' at all, there first has to be an explosion. Which is one of the points you continue obdurately to maintain. Read my lips: there are no explosions in LNG accidents, for purposes of this discussion.
Find me a reference for LNG cars ... mind you, not LPG cars ... being 'tossed a half mile or more'.
WizlishI would assume that a fairly large number of dewar tankers would be damaged enough to leak patently, in an accident with the force of what happened at Lac Megantic, and I would be unsurprised if the released cryomethane did not cause damage to some other cars. On the other hand, let me repeat that the likelihood of an explosion from cryomethane is extremely, EXTREMELY unlikely... do you not like to read the references I provided?
One other difference between a petroleum fire and an LNG fire is that there are almost no molecules with carbon-carbon bonds in LNG. Without the C-C bonds, there is much less soot produced and the flame emits far less infrared radiation. The downside is the flames are harder to see.
Someone had posted a video on YouTube of an open air natural gas "explosion" (deflagration)- looked more like a very strong gust of wind than a detonation wave. Looked like the tree, poles and buildings got a minor scorching.
Keep in mind that the high pressure gas lines occasionally get punctured or burst. A recent exmple of the latter is San Bruno, California.
- Erik
P.S. There is a big difference between deflagration and detonation. In a gasolene engine, deflagration is normal combustion, detonation is what causes knocking. The detonation results from the gas/air mixture being confined under great pressure.
Listen to Mike about this. It seems to me that you're continuing to assume incorrectly.
The problem at Lac Megantic was due to explosions and then combustion of hydrocarbons at ambient temperature. A similar incident with cryomethane would have resulted in flash-freezing an extensive area, with some likelihood of flash gas fires (probably fairly quickly extinguished due to local lean conditions) until the pool of cryo material began heating up -- likewise, most sources of ignition from the accident itself will be rapidly chilled below the temperature they would serve as ignition sources for a rich enough gas cloud.
I would assume that a fairly large number of dewar tankers would be damaged enough to leak patently, in an accident with the force of what happened at Lac Megantic, and I would be unsurprised if the released cryomethane did not cause damage to some other cars. On the other hand, let me repeat that the likelihood of an explosion from cryomethane is extremely, EXTREMELY unlikely... do you not like to read the references I provided?
The risk is of late ignition, and starting a pool fire. That will rapidly escalate to a situation where reliable flameholding for any other pools will exist, and you will have a hot, perhaps disseminated fire until the gas has boiled off. That may be enough for many people to dislike the idea of bulk shipment of LNG in unit trains; indeed, it's enough for me not to like the idea of bulk shipment of LNG in unit trains or blocks. But you need to get your reasons straight, and not keep arguing about the wrong ones.
EuclidCertainly reason #1 is true. But is reason #2 true or false?
I don't think there's a 'straight' answer to that, any more than there's a noncomplex answer to why some railroads say quiet zone crossings are less safe than those where horns are sounded.
Bakken crude-oil fires vs. those for some other types of crude already show a great difference. I think that's already been covered to death in the various Lac Megantic beatdowns.
LNG probably has less propensity to prompt ignition in a typical railroad accident: it's inside an armored Dewar, comes out as a cold liquid, and as noted its vapor is initially very cold and a substantial mass of cold vapor has to be brought up to transition temperature before combustion reactions will be sustained in the gas plume. On the other hand, once that combustion is initiated above a gas plume the fire will be hotter, although still non-explosive.
The worry I have with natural-gas fires in general is if they occur in a confined space, or if the LNG liquid or dense vapor flows into confined spaces (as in part of the accident in Cleveland and is exposed to an ignition source. Critical-mixture combustion produces great heat release in a short period of time, and when the mixture is confined the flame-front propagation easily goes from normal burning to detonation. See this reference from Combustion and Flame, or this one which describes some of the parameters, for example (there are many other references). Midland Mike can take over to describe how the vapor from various crudes compares.
In any case, there is comparatively little likelihood that the capital needed to construct long trains of insulated Dewars for LNG 'service' would be used for that purpose instead of building better and safer oil trains. But that's a whole nother thread.
EDIT: I give up on getting this Bangalore software to make that first link live: it's www.dtic.mil/get-tr-doc/pdf?AD=ADA520957
Here is an introductory reference for unconstrained gas clouds.
I can see two possible reasons why people might oppose adding LNG trains to the railroads:
1) Adding LNG would simply add more fire and explosion hazard to rail traffic.
2) Adding LNG would add fire and explosion hazard that is more severe and more dangerous than the fire and explosion hazard of crude oil.
MidlandMike Overmod ... Liquid methane changes state to gas, relatively smoothly and more from its surface than via nucleate boiling; gas is lighter than air at equivalent temperature and rises and dissipates much as any gas leak would -- it is cold, just as CNG is after release from a breach, but doesn't mix (and carburete) as readily since the turbulent mixing caused by pressure release from compressed pressure is absent. ... "gas is lighter than air at equivalent temperature" The thing is that methane gas evolving from LNG has a temperature about half way to absolute zero from ambient (air) temperature. Since methane is about half the molecular weight of air, the temperature difference between the air and gas, would leave them at about the same density. (IIRC my college chemistry)
Overmod ... Liquid methane changes state to gas, relatively smoothly and more from its surface than via nucleate boiling; gas is lighter than air at equivalent temperature and rises and dissipates much as any gas leak would -- it is cold, just as CNG is after release from a breach, but doesn't mix (and carburete) as readily since the turbulent mixing caused by pressure release from compressed pressure is absent. ...
... Liquid methane changes state to gas, relatively smoothly and more from its surface than via nucleate boiling; gas is lighter than air at equivalent temperature and rises and dissipates much as any gas leak would -- it is cold, just as CNG is after release from a breach, but doesn't mix (and carburete) as readily since the turbulent mixing caused by pressure release from compressed pressure is absent.
...
"gas is lighter than air at equivalent temperature" The thing is that methane gas evolving from LNG has a temperature about half way to absolute zero from ambient (air) temperature. Since methane is about half the molecular weight of air, the temperature difference between the air and gas, would leave them at about the same density. (IIRC my college chemistry)
Not claiming to be a pool-fire expert here -- but look at your college physics, too. As soon as a molecule of CH4 at cryo temp has reached the gas phase, it mixes with (ambient) air following gas kinetics, and therefore will heat far more rapidly than the underlying pool, becoming gradually lighter as it does so, but as you note, remaining substantially denser than the surrounding atmosphere for some time. That is part of the reason why LNG pool fires can be so intense - there is a 'rich mixture' proportion of fuel in the gas state close to the pool, and should there be ignition of the gas plume at any point, the heat release will almost certainly amplify the turbulent mixing of that plume as well as the rate of phase change from liquid to gas at the pool surface.
For those who were counting molecular weights and wondering why CH4 is about half the atomic weight of air, remember that both major constituent gases in the atmosphere are diatomic -- N2 and O2.
It's a cold liquid, behaving much like liquid nitrogen (although not as cold). Has relatively low viscosity, so it flows from breaches and seeks the lowest level fairly readily. Both the liquid and the gas cloud evolving from it are made visible as moisture in the air changes state. Liquid methane changes state to gas, relatively smoothly and more from its surface than via nucleate boiling; gas is lighter than air at equivalent temperature and rises and dissipates much as any gas leak would -- it is cold, just as CNG is after release from a breach, but doesn't mix (and carburete) as readily since the turbulent mixing caused by pressure release from compressed pressure is absent.
One other detail: there is little or no odor to cryomethane, as the mercaptans etc. that are odorants in typical 'gas' freeze out long before methane. That means you need good and sensitive methane detectors, particularly at accident sites.
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