How much payload capacity is sacrificed in implementing this 'solution'? How much of the catalytic agent is required to perform the chemical reaction on a fully loaded car (nominally 30K gallons for both oil and catalyist)? Is the reaction endothermic or exothermic? What is the specific trigger mechanism that causes the deployment of the catalyist?
Never too old to have a happy childhood!
A couple questions that are unanswered:
1. What powers the system?
2. What triggers a release of the chemicals? Derailment or breaching?
3. Does it activate the whole train or just the cars involved?
4. Does it activate the cars in the area or just the cars involved?
5. Does it differenciate between loads and empties?
6. How fast does it deploy, how fast does it activate?
7. An additional failure mode not addressed is when the car is heated by fire and the car fails due to pressure from the heated commodity and weakening of the tank wall. What happens when the treated oil is heated, do the chemicals continue to behave in a protective mode? Does the treated oil have less of a tendency to rupture when subjected to heat? Do the chemicals have any effect on the volitiles dissolved in the oil?
Dave H. Painted side goes up. My website : wnbranch.com
These and Balt's questions are good ones. I do suspect that many of them can only be answered by the inventor with "TBA" as he specifically notes that details of how and what the sensors do, and how they activate the chemical 'suppression' system, are not part of what he's discussing. In my opinion there are some commonsense answers and perhaps theoretically 'best practices' in how the actuation would be done, but at this point the inventor is concentrating on what happens when the suppression device is triggered.
dehusmanA couple questions that are unanswered: 1. What powers the system?
The sensors will probably generate an electrical signal. The actual 'power' to inject the agent and mix it with the mass of oil in the car will probably involve either pressurized gas or some sort of gas generator (which I think, at the speed and volume required, would almost certainly involve pyrotechnics, hypergolics, or energetic chemical reactions of some sort).
Presumably something very severe -- much more severe than any usual longitudinal buff shock or suspension vibrations. My suspicion is that there will be several parallel 'sensor' systems that would be involved, and that in some cases multiple systems would need to activate in order to fire the irreversible reaction.
In my opinion, breaching is FAR too late; the energy involved in injecting and mixing the agent would surely have the effect of presurizing the contents and ejecting some from the breach, likely inducing precisely the effect, albeit at smaller scale, that the system was intended to avoid.
I would say the most logical approach at present would be to use the Spanish-style derailment sensor; it would make at least as much sense to use this (delayed if desired) for cargo passivation as to trigger an unexpected emergency event.
To me, common sense would dictate that the system only operate on cars actually involved in an immediately dangerous condition. Removing crosslinked 'solidified' oil even from a layer blanketing the tank walls is going to be a seriously expen$ive operation. Purifying the emulsified load is likely to be bottom-line expensive, too, to say nothing of the delay in receiving the feedstock.
Agqin, I would think the 'prompt' system wold only work on actual endangered cars during the accident. Yes, there would probably be delayed temperature sensors that would activate the system on 'nearby' cars if fire from another source threatened them, or perhaps if someone in authority decided to 'safe' those cars.
This is an interesting question, and it will be interesting to see if the inventor realizes it. This is comparable to whether or not you fire the inertia-reel tensioner on an automobile seatbelt that is not buckled around an occupant -- note the added system complexity and potential points of failure or false triggering that are introduced.
There is also the question that even "empty" cars will contain considerable hydrocarbons and may benefit from passivation, In my opinion it would be suboptimal to design a 'partial release' of the agent in the mini-tanks depending on the relative fullness or liquid level of the material in the car -- it would either fire 100% or be kept safed for empties. One of many considerations is whether a separate safety provision -- say, pressurization of the car with nitrogen -- is detected, tested for, and allowed to keep the safety system turned off.
Note how carefully the inventor does not answer this. It is possible that the actual 'mixing' time could be longer than the accident duration, but the typical public assumption would be that it does whatever it does to 'safe' the cargo before an explosion can develop, and that is a comparatively short time (during which the detection, actuation, full deployment and mixing of the agent, and a great deal of the subsequent reaction all go to completion). As noted, I think any system capable of roiling light crude this much in this short a time is a terrifically hazardous thing if there is a large percentage of dissolved hydrocarbon that wants to be in the gas phase at ambient temperature -- as there was in much of the Bakken and Eagle Ford crude shipped up until recently.
7. An additional failure mode not addressed is when the car is heated by fire and the car fails due to pressure from the heated commodity and weakening of the tank wall. What happens when the treated oil is heated, do the chemicals continue to behave in a protective mode?
The emulsified oil will take a much longer time to heat up due to the large heat capacity of the water content. I do not know if heated emulsions of oil outgas substantially before the water reaches the boiling point. I would be nominally concerned about the possibility of a steam explosion acting to vaporize superheated emulsion, with the dry steam at an elevated 'flash' temperature posing comparatively little resistance to ignition of the oil content.
I would expect some tendency for the crosslinking bonds to break at elevated temperature, but also some tendency for further crosslinking at moderately elevated temperature. The result might tend to char instead of degrading to flammable oligomers. I don't yet know enough organic chemistry to do more than speculate, but someone with distinctive competence can give you a minute-by-minute discussion of what happens as solidified oil is heated.
Does the treated oil have less of a tendency to rupture when subjected to heat? Do the chemicals have any effect on the volatiles dissolved in the oil?
This is two questions that I think have very different answers. The emulsified oil will have much less tendency to rupture when heated, compared to untreated crude oil. The difficulty with steam in the emulsion is as I indicated above: if the water in an emulsion superheats and then phase-changes in a rupture, the effect may be dramatically worse than with crude alone.
I do not think either approach works on the volatiles, and this is a severe potential shortcoming that I don't think 'matters' to the inventor, although for HHFTs I think it should. It's an interesting consideration whether an agent might react with volatile monomers in a way that condenses them effectively, either by reaction or crosslinking. I'm of the impression, though, that an agent that could do this adequately with the considerable volatile content of Bakken or Eagle Ford crude would react with considerable exothermia -- which is not a good thing here.
WizlishThe difficulty with steam in the emulsion is as I indicated above: if the water in an emulsion superheats and then phase-changes in a rupture, the effect may be dramatically worse than with crude alone.
As I recall, water is sometimes added to the exhaust of jet engines to increase their thrust. Water in an enclosed container will "BLEVE" just as well as any flammable substance, except that pure water obviously won't burn. Water mixed with a flammable substance, however, may well be dramatically worse, as you note.
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...
There's dumb ideas but this one takes the cake. Any thing that could mix 30,000 gallons in seconds would be more violent than the potential release of the product. In addition he claims to have "surfactants" but they are useless with out a supply of water. All in all, this is even dumber than the idiot in Canada leaving his train on air.
EuclidI suggest to the inventor that he place a single, larger surfactant reservoir on the outside of the oil tank. It might be something like a saddle tank or saddle bag that occupies some of the available space between the oil tank and the clearance diagram.
With respect, you're looking at the wrong thing. Read tgmidget's post again, and then look at what the inventor claims is the advantage of his 'surfactant' approach. The added capacity needs to be the water that forms the emulsion.
That is a sizable mass of water.
The amount of surfactant, whether biodegradable sorbitan-based or more powerful, is easily accommodated in the size and location of the mini-tanks the inventor mentions. I do not think you can provide sufficient tankage for the required water mass in that location, or make the railcar's dynamics as a moving vehicle at all satisfactory if you were to try. This gives you the delightful opportunity to propose where the tanks for the emulsion water should go, whether the surfactant (or some other adjuvant material) will act suitably as antifreeze in the often-harsh Canadian climate, and how the water as well as the surfactant will be meaningfully admixed with the crude.
Let me repeat here, before we get arguing about the wrong things, that it does not appear that this 'version' of the system is really intended to protect against impact problems. It's much more directed against fire resistance and 'environmental protection', which probably permits slower and less energetic/dangerous mixing than the kind of oil-train protection systems we've been discussing in this thread would need -- and that no few of us have been tacitly assuming this Canadian system would use. It remains to be seen if the system can, in fact, be made quick-acting, and I basically agree with the midget that it really can't be.
I am beginning to think that the only really "practical" way (this is like the first law of consulting; even the 'most practical solution' may not really be practical or suitable, or much of an actual solution, at all!) to disperse the water and surfactant adequately and then assure mixing is to have some kind of manifold within the tank volume, running a good percentage of the length of the tank if not in fact full length, with nozzles all up and down it, which contains the surfactant and water and is pressurized upon 'activation' to produce spray radially outward. This will decrease the payload volume, but perhaps not uneconomically so considering the car cannot be operated 'full' for other reasons, and the provision of the safety system might allow thinner shell gauge, or reduced armoring or thermal insulation on the shell.
Doesn't water still freeze at 32 degrees F? With Baaken crude coming from the Dakota's - winter temperature there and through most of the Northern US and Canada is well below 32.
BaltACDDoesn't water still freeze at 32 degrees F? With Baaken crude coming from the Dakota's - winter temperature there and through most of the Northern US and Canada is well below 32.
There will be some freezing-point elevation from the surfactant if it is well chosen. Obviously not sufficient for a Canadian winter. I'm certain the inventor knows ... or ought to know ... that his water needs to be kept well insulated, probably with one of the modern nanoinsulation techniques like aerogels, and provided with some sort of heat-tracing arrangement to keep all the pipes and nozzles open.
In partial defense of my entirely non-serious location for the manifold: if the oil is kept at some reasonable temperature to make it ready to flow upon arrival, this will automatically keep water mixture in tankage 'within' the oil volume at proper temperature also, while minimizing the number of penetrations needed in the actual tank shell and the insulation and heating arrangements needed externally. Someone like Midland Mike is much more conversant than I am with the specific methods used to make the oil fluid, but not excessively 'hot', for best terminal handling.
Wizlish Euclid I suggest to the inventor that he place a single, larger surfactant reservoir on the outside of the oil tank. It might be something like a saddle tank or saddle bag that occupies some of the available space between the oil tank and the clearance diagram. With respect, you're looking at the wrong thing.
Euclid I suggest to the inventor that he place a single, larger surfactant reservoir on the outside of the oil tank. It might be something like a saddle tank or saddle bag that occupies some of the available space between the oil tank and the clearance diagram.
With respect, you're looking at the wrong thing.
EuclidI had no intention of choosing the “right thing” to look at. So I find it odd that you would take issue with that point. My point is to look at one thing out of many.
Aw, it was just a rhetorical device in English, to indicate you were looking at the surfactant when the water is far, far more important to the design.
In any case, his original design clearly shows where he intends the external tankage to go, and how it would be arranged.
I only tossed the invention by Iman Chalibi on the table in case you or others wanted to comment about it. I have no stake in it. I am not defending it. Like you and others, I see lots of practical problems with the idea. I am just adding my thoughts about the storage tank to the list of comments because nobody has mentioned it.
But if you are going to add thoughts, at least add complete ones, which aren't already covered in the source material better than you're commenting on them.
When I suggested a saddle tank or saddle bag, that's just a general description of an external tank. Specifically, the best location would be on either side of the lower half of the oil tank
Note that's not where the inventor put them. I think he is depending on gravity as part of his dispersal system, but I can't be sure because too many of the details are left out of his presentation to tell. As noted, you would not want to put the water there. I do agree that if you want external tankage for the water+surfactant, the location you describe is a very reasonable place to put it.
... why stuff the extra equipment of this invention into the payload tank when it can be hung on the outside where it will be easier to inspect and maintain?
For the reasons I gave, to start with.
It is perfectly possible, of course, to keep all the emulsification stuff external to the tank volume, and do it in the manner you propose. That is probably the likeliest way a Canadian company would construct it. You will need insulation and tank heating, including tracers for the lines going to the nozzles into the tank. You might want to speculate on how many nozzles there would need to be, where they would be located and aimed, what their spray pattern would be, etc.
What would you use as the driving agent for a system where the water is held in external tanks in this location? How would you communicate the driving agent to the water -- put it under hydrostatic pressure, pump it, entrain it? How quickly would you need to accomplish the emulsion mixing, and would you prioritize any parts of the internal volume (e.g., ends or bottom periphery of the tank first)?
Wizlish ... In partial defense of my entirely non-serious location for the manifold: if the oil is kept at some reasonable temperature to make it ready to flow upon arrival, this will automatically keep water mixture in tankage 'within' the oil volume at proper temperature also, while minimizing the number of penetrations needed in the actual tank shell and the insulation and heating arrangements needed externally. Someone like Midland Mike is much more conversant than I am with the specific methods used to make the oil fluid, but not excessively 'hot', for best terminal handling.
...
My experience is in the oil fields of Michigan, so I am somewhat familiar with cold weather oil operations. The crude oil comes from the well already somewhat warm (relative to winter temperatures) and then goes immediately to a production facility, which usually involves a heater treater to separate the oil/water phase of the production fluid. The downhole pump can somewhat emulsify the oil/water mixture, so heat is what helps to separate them out. It was brought up earlier, as to what an oil train fire might do to a tank car whose contents were emulsified by the safety process under discussion. I don't know how the chemicals would affect things, but otherwise the tendency would be for the demulsifying and offgassing.
The crude oil is stored at the well production facility only until there is a truckload to haul out. The oil does not have much chance to cool. I don't believe that after a few hours in the truck, that there would be a problem unloading the crude. Michigan light crude has about the same viscosity as Bakken Crude. You would have to ask someone at a refinery if they have problems unloading tank cars of cold Bakken, but I doubt it. Heavy crudes are often carried in tank cars with steam coils, for loading/unloading.
James
The Butlerhttp://www.komonews.com/news/local/BNSF-declines-to-stop-running-oil-trains-past-Seahawks-games-330172941.html
If they're so worried about oil trains why did they build the stadium next to a mainline? They're like the idiots who build at the departure end of a major runway and then complain about noise.
Norm
1. This is right next to King Street Station and trains run through its approach switches. Trains NEVER move more than 25 MPH through there, and at that speed they wouldn't even rupture, even if DOT-111s.
2. Great Northern tunnel underneath the streets and skyscrapers of downtown Seattle is a far bigger risk.
3. Interbay derailment was a split switch in a yard at 5 MPH. No risk of spill, fire, explosion, etc. That fender-bender won't kill you.
4. What is the "Transcontinental Route"? It's Stevens Pass or the Scenic Subdivision. The SP&S is on a transcontinental route, too. Please, go to the effort to get correct information. Iron Triangle exists for good reason; BNSF isn't stopping it.
5. Risk is far larger for TIH gasses.
Really poor article overall. Go 'Hawks!
Remember this about the media.
They have nothing to sell but fear! And they do a good job of it.
BaltACD Remember this about the media. They have nothing to sell but fear! And they do a good job of it.
Johnny
Perhaps the powers that be should have told them not to build the stadium there.
But, isn't the stadium close to public transportation, which should reduce street traffic to/from the stadium? By the way, what is the source of the fuels for public transportation?
Due to close clearances of the Great Northern tunnel under the city center and abundance of crossings nearby on the waterfront, trains do not travel fast enough to have a multiple car fire/explosion like we have seen elsewhere. They never have. There is no risk that requires operational changes.
It isn't about the trains, it is about the oil, which is a four-letter word in the PNW. (Except, of course, when one is burning it themselves.)
The stadiums are right next to King Street Station, and Sounder runs game day specials. Safeco Field's roof extends out over the tracks. LPG trains and other even more explosive chemicals have been running through there long before the stadium was built. If exploding trains were a huge danger, why did the designers still build over the tracks?
Broken rail: http://news.yahoo.com/officials-reveal-cause-west-virginia-train-derailment-125703936.html
-Don (Random stuff, mostly about trains - what else? http://blerfblog.blogspot.com/)
oltmannd Broken rail: http://news.yahoo.com/officials-reveal-cause-west-virginia-train-derailment-125703936.html
As I recall from FRA stats, rail and roadbed problems are the leading cause of derailments.
C&NW, CA&E, MILW, CGW and IC fan
Now do you understand why when there was all the clamor for the exotic brake systems I was advocating for better rail/track defect detection?
WilliamKiesel Prevention must be zero tolerance, absolute; given the nature of Bakken crude oil.Bakken crude oil is a stratified multi constituent liquid. Its weight is such that something like 28,000 gallons are the weight limit for a 30,000 gallon tank car. Visualize the 2000 gallons as about 36 drums of 55 gallon capacity. That's quite a bit of empty space inside a tank car. It is about 269 cubic feet. What is the factor of cargo sloshing in the tank cars? What are the fluid dynamics for a stratified liquid such as Bakken crude? How does the distributed inertia and viscosity of Bakken crude contribute to unstable vehicle dynamics and rail/ wheel interaction? Might skin friction result in the tank due to sloshing creating localized heating, stress and failure? Are boiling liquid expanding vapor events (BLEVE) causing the derailments?Are the braking dynamics of ordinary air brakes contributing to slosh and a series of events leading to failure? Is there an optimal speed of operation for Bakken crude? Is there a maximum number of tank cars not to be exceeded? Is the draft gear and energy absorption of the tank cars adequate for handling Bakken crude.These are the questions must be examined. The inherent problem with railroad tank cars is that they are stupid. That is, there are no sensors on the tank cars to identify what the cargo is doing and how it affects vehicle dynamics. Knowing what is going on n the tank is first and foremost needed. FRA PHMSA announcement simplly dela with stupid vehicles, rail tank cars. Given the potential and reality for catastrophe smart railroad cars need to part of the problem solving.
Prevention must be zero tolerance, absolute; given the nature of Bakken crude oil.Bakken crude oil is a stratified multi constituent liquid. Its weight is such that something like 28,000 gallons are the weight limit for a 30,000 gallon tank car. Visualize the 2000 gallons as about 36 drums of 55 gallon capacity. That's quite a bit of empty space inside a tank car. It is about 269 cubic feet. What is the factor of cargo sloshing in the tank cars? What are the fluid dynamics for a stratified liquid such as Bakken crude? How does the distributed inertia and viscosity of Bakken crude contribute to unstable vehicle dynamics and rail/ wheel interaction? Might skin friction result in the tank due to sloshing creating localized heating, stress and failure? Are boiling liquid expanding vapor events (BLEVE) causing the derailments?Are the braking dynamics of ordinary air brakes contributing to slosh and a series of events leading to failure? Is there an optimal speed of operation for Bakken crude? Is there a maximum number of tank cars not to be exceeded? Is the draft gear and energy absorption of the tank cars adequate for handling Bakken crude.These are the questions must be examined.
The inherent problem with railroad tank cars is that they are stupid. That is, there are no sensors on the tank cars to identify what the cargo is doing and how it affects vehicle dynamics. Knowing what is going on n the tank is first and foremost needed.
FRA PHMSA announcement simplly dela with stupid vehicles, rail tank cars. Given the potential and reality for catastrophe smart railroad cars need to part of the problem solving.
16 pages of discussion until someone said the magic 'word'- BLEVE. However, as I understand the situation, BLEVE's occur after the derailments, and the initial cause may be as simple as valve handles which are TOO Strong.
Here's my logic: The unloading valves on the bottom of the cars have handles roughly 3 feet long. These handles are supposed to break away in derailments where the bottom of the car contacts the R-o-W. That's an AAR/FRA requirement. If it doesn't, it either opens the valve or tears it off the car, causing a breach.
In a roll over, that valve is much less likely to be the issue. Then you have to look at top fitting protection. If insufficient, the loading valve and/or relief valve can be torn from the car, again causing a breach.
Once this happens to *about* five cars and enough oil leaks out, the next issue becomes a 'pool fire'. The oil vapor (and other vapor components) are burning, but not explosively, since the oil isn't pressurized. If the pool fire is burning under a non-breached car for a long enough period, the BLEVE scenario begins.
As the oil heats up and expands in the tank car, the internal pressure rises, opening the relief valve at it's preset pressure. This sprays pressurized, atomized oil, which can be ignited into a 'blow-torch' until the pressure relieves and the relief valve shuts.
Now, there's less liquid in the tank to absorb the heat of the pool fire. So, the tank skin begins to heat up more rapidly, along with the remaining oil in the tank. It's possible that the relief valve may open again, repeating the cycle.
Eventually, the oil level in the tank gets low enough to allow the steel above the oil level to thermally fatigue (as long as the pool fire is still heating the tank). Once that ruptures, the release of pressure allows the rest of the oil to flash over to vapor and the expanding mixture ignites, making the large explosions seen in post-derailment videos.
Fix the valve handle, save the BLEVE.
(My apologies if similar info comes up later in the thread, I haven't gotten to the end yet.)
RDG467Fix the valve handle, save the BLEVE.
BLEVE - "Boiling Liquid Expanding Vapor Explosion"
BLEVEs occur when two things happen:
1. Something heats up the container, and thus the product inside that container.
2. Something causes the container to fail. Usually the failure is directly related to the fire impingment. Firefighters are trained to get copious amounts of water on said point, if possible.
Your description is fairly accurate.
While the valve may well be one factor in providing the fuel for a fire, there are many others, including structural failure of the container as a result of the incident. This is the reason for head shields and the thicker metal called for in the new standards.
Mr Kiesel gets one important thing backwards - BLEVE's are a result of the incident, not the other way around. Statements like his are the cause of illogical panic - "rolling bombs."
Keep the cars on the rails and the problem will be negligible. Every Bakken incident so far has initially been due to failures wholly unrelated to the product being carried.
dehusman Now do you understand why when there was all the clamor for the exotic brake systems I was advocating for better rail/track defect detection?
I think you need both. Even though those two wrecks were caused by rail failure, my exotic brake system may have prevented each wreck from burning.
Larry, thanks for the reminder- I read Mr. Kiesels's description at least three times, knew that the last E was for Explosion, and forgot to add that to my post.
I was being a bit facetious with my last sentence- obviously this is a very complex subject with many variables and I didn't want to imply that those valves were the only one. I do remember seeing pix at Lac Megantic of rail punctures in some tank car heads. IIRC, that was one of the few derailments that happened on stick rail.
I did want to say, at the risk of obliterating the last bones of this poor horsie, a major contributor to these incidents may be something as simple as a valve handle that did not meet it's specificiations to break off when it should have.....
There is the probablity that some of the other derailments which 'appear' to have broken rails as part of the cause, may have had breaching from that break, or other breaks that were not visible in the available pix posted to the 'net. I think the Galena incident on BNSF started at a switch at the south end of the yard, but it hasn't been determined yet if trackwork was the main cause for that derailment, afaik.
I haven't read the Lynchburg reports, but will download and pore over them with great interest.
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