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  1. #21
    Forum Member GTRider245's Avatar
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    Assuming the hole is in the vapor space, the tank is not in an area where it could harm anyone and we have time to wait, keep a fog pattern in the VAPOR CLOUD not touching the tank and let it leak and autorefrigerate. Problem solved.

    Kinda wondering how that just now came up...
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    Quote Originally Posted by GTRider245 View Post
    Assuming the hole is in the vapor space, the tank is not in an area where it could harm anyone and we have time to wait, keep a fog pattern in the VAPOR CLOUD not touching the tank and let it leak and autorefrigerate. Problem solved.

    Kinda wondering how that just now came up...
    Fireman said... roll the tank so that the hole is in the vapor space

    JBRescue said... Second, unless letting this vent to atmosphere is going to cause a problem, put a fog stream on it and let it do its thing.

    Just to name a few from the beginning of the thread....

    Not really seeing a problem if the pattern actually touches the tank so that's a new one on me. So why would NOT want touching the tank itself w/ a pattern be an issue??

    Be safe, R2

  3. #23
    Forum Member GTRider245's Avatar
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    Quote Originally Posted by robertr2m View Post
    Fireman said... roll the tank so that the hole is in the vapor space

    JBRescue said... Second, unless letting this vent to atmosphere is going to cause a problem, put a fog stream on it and let it do its thing.

    Just to name a few from the beginning of the thread....

    Not really seeing a problem if the pattern actually touches the tank so that's a new one on me. So why would NOT want touching the tank itself w/ a pattern be an issue??

    Be safe, R2
    Becuase as long as water is touching the tank, the tank will stay warm enough to keep the LP from autorefrigerating. THAT'S the part that no one else hit on. Once you get it to AR, no more offgasing and you can literaly go up to the tank and look inside at the liquid in the bottom, with no danger to anyone. There will also be a nice layer of ice around the bottom of the tank.

    Problem solved.
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  4. #24
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    Quote Originally Posted by GTRider245 View Post
    Becuase as long as water is touching the tank, the tank will stay warm enough to keep the LP from autorefrigerating. THAT'S the part that no one else hit on. Once you get it to AR, no more offgasing and you can literaly go up to the tank and look inside at the liquid in the bottom, with no danger to anyone. There will also be a nice layer of ice around the bottom of the tank.

    Problem solved.
    I'm still not following you.

    Tech's on Propane...
    Propane is a hydrocarbon fuel, chemical description C3H8.
    Its boiling point is -44°F (-42°C)
    Its octane rating is 104
    Latent heat of vaporization = 183 BTU’s / lb (426 kJ/kg)
    91,500 BTU’s per gallon (25300 kJ/L)
    Autoignition temperature 855°F (457°C)
    Stoichiometric by weight = 15.5:1
    Molecular weight = 44.09
    Carbon % by weight = 89%
    Hydrogen % by weight = 18%
    Flammability limits = 2.1 – 9.6%
    Viscosity at 68°F = 0.592 BTU/lb °F (2.48 KJ/Kg °K)
    Expansion rate = 270:1 (expands in volume 270 times from liquid to ambient pressure vapor)
    LPG is auto-refrigerating, when pressure is reduced, it boils by absorbing heat

    The point that needs to be considered...
    Propane’s vapor pressure (the amount of pressure required to keep LPG liquid at ambient temperatures) is zero at -44°F (-42°C), about 120 psig at 70°F, about 250 psig at 125°F, and close to 400 psig at 160°F.

    Based on what I know is true about propane... I doubt you will be able to ever actually see it uncontained other than the white vapor could aka propane steam.

    Autorefrigeration is the really big word for when the liquid boils off (or phases from a gas to a liquid) as it absorbs heat cooling the remaining liquid. LNG and LPG are both kept at there boiling point so that if they do encounter heat, the liquid will vapor off (or bowl) and cool the remaining liquid. To the best off my knowledge, this is achieved by valving.

    I am not seeing how this will stop the described Propane tank from leaking or how water will adversly effect it. My thought is that water will warm the vessel to stop ice from forming at the leak. I can see where water may warm the vesselt so it phases at a faster rate but the difference would be minutia in my humble opinion.

    If I'm missing something, please let me know.

    Be safe, R2
    Last edited by robertr2m; 02-02-2009 at 02:20 AM.

  5. #25
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    Robert I think what GT rider is trying to say is that once the propane drops below it's boiling point all you have left is liquid with little to no vapor off gassing..... The bottom of the tank (liquid level) usually ices up.

    By adding the water you raise the BP and increase vaporization (warms tank).....

    Ron Gore years ago taught us something about this .... He said it happens more then most people know, they usually stand back & let the tank vent.... The tank usually auto refrigerates, most responders don't recognize that fact, they assume the tank is now empty but in fact it's not....

  6. #26
    Forum Member GTRider245's Avatar
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    Quote Originally Posted by ClariantERT View Post
    Robert I think what GT rider is trying to say is that once the propane drops below it's boiling point all you have left is liquid with little to no vapor off gassing..... The bottom of the tank (liquid level) usually ices up.

    By adding the water you raise the BP and increase vaporization (warms tank).....

    Ron Gore years ago taught us something about this .... He said it happens more then most people know, they usually stand back & let the tank vent.... The tank usually auto refrigerates, most responders don't recognize that fact, they assume the tank is now empty but in fact it's not....
    Thank you for saying what I was having trouble comming up with. That is the exact concept that I was describing.

    And Gore is the one who taught me about it as well. A group of us from here went down to Wellbourne for 4 days back in October for his Leak, Spill and Fire Control class at it was one of the most enlightening expiriences I have ever had. The man knows his stuff, and we did some things in that class that I never would have attempted before. Also one of the only classes I know of that uses live product for the training. I would reccommend it to anyone.
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  7. #27
    Forum Member GTRider245's Avatar
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    Double post.
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    Quote Originally Posted by Rescue101 View Post
    I don't mind fire rolling over my head. I just don't like it rolling UNDER my a**.

  8. #28
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    Quote Originally Posted by GTRider245 View Post
    Thank you for saying what I was having trouble comming up with. That is the exact concept that I was describing.

    And Gore is the one who taught me about it as well. A group of us from here went down to Wellbourne for 4 days back in October for his Leak, Spill and Fire Control class at it was one of the most enlightening expiriences I have ever had. The man knows his stuff, and we did some things in that class that I never would have attempted before. Also one of the only classes I know of that uses live product for the training. I would reccommend it to anyone.
    Very knowledgeable guy….. Straight forward and to the point…. He has probably forgotten more then he knows. LOL..

    He has some disdain for a lot of agencies & departments in this area…. But if you go to one of his classes & keep your ears & eyes open and your mouth shut. You will come away with a LOT of useful knowledge….

  9. #29
    Forum Member nmfire's Avatar
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    Getting back to the original topic, I think the first order of buisness would be beating the owner of the tank upside the head a few times with a haligan.
    Even the burger-flippers at McDonald's probably have some McWackers.

  10. #30
    Forum Member GTRider245's Avatar
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    Quote Originally Posted by ClariantERT View Post
    Very knowledgeable guy….. Straight forward and to the point…. He has probably forgotten more then he knows. LOL..

    He has some disdain for a lot of agencies & departments in this area…. But if you go to one of his classes & keep your ears & eyes open and your mouth shut. You will come away with a LOT of useful knowledge….
    Well he pretty much wrote the book on it. So I just shut up and listened. Pretty much threw out 90% of the things were taught in ops and tech, as well as killed almost all our thoeries on decon.

    I did some things there I never thought possible. Drove a metal plug into a leaking LPG tank...replaced a leaking relief valve under pressure...flared LPG and then put out the fire we set...it was nuts.

    Awesome class though. Changed my veiw on hazmat all together.
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  11. #31
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    Quote Originally Posted by GTRider245 View Post
    Well he pretty much wrote the book on it. So I just shut up and listened. Pretty much threw out 90% of the things were taught in ops and tech, as well as killed almost all our thoeries on decon.

    I did some things there I never thought possible. Drove a metal plug into a leaking LPG tank...replaced a leaking relief valve under pressure...flared LPG and then put out the fire we set...it was nuts.

    Awesome class though. Changed my veiw on hazmat all together.
    Yea we did a lot of that as well......

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    Ok... I see what your saying, thanks for the clarification. Same word, two different applications of the results

    I honestly don't agree that this would be an acceptable way to mitigate this particular tank (or any other) but hey, I'll keep it in the back of my head if the situation ever presents itself.

    Regardless, I'm going to check into that class. Can't train enough, especially in HAZMAT.

    Be safe, R2

  13. #33
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    Quote Originally Posted by robertr2m View Post
    Ok... I see what your saying, thanks for the clarification. Same word, two different applications of the results

    I honestly don't agree that this would be an acceptable way to mitigate this particular tank (or any other) but hey, I'll keep it in the back of my head if the situation ever presents itself.

    Regardless, I'm going to check into that class. Can't train enough, especially in HAZMAT.

    Be safe, R2
    LOL..... Thats okay.. Just don't ever tell Ron you don't agree...... Here's a link to his web site.

    http://www.safetysystems-rongore.com/index.html

  14. #34
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    Sweet... thanks

    Be safe, R2

  15. #35
    Forum Member GTRider245's Avatar
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    Quote Originally Posted by robertr2m View Post
    I honestly don't agree that this would be an acceptable way to mitigate this particular tank (or any other) but hey, I'll keep it in the back of my head if the situation ever presents itself.
    Why not? What part isn't acceptable? In the ways mentioned, we let the tank vent until it is empty. WHo knows how long that will take. In the way I mentioned, the tank eventualy stops venting, much quicker.
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    Quote Originally Posted by Rescue101 View Post
    I don't mind fire rolling over my head. I just don't like it rolling UNDER my a**.

  16. #36
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    Quote Originally Posted by GTRider245 View Post
    Why not? What part isn't acceptable? In the ways mentioned, we let the tank vent until it is empty. WHo knows how long that will take. In the way I mentioned, the tank eventualy stops venting, much quicker.
    After thinking a minute on this, I decided to take the approach...

    In the ways mentioned, we let the tank vent until it is empty. WHo knows how long that will take.
    You are mistaken or you didn't read all the posts. I recall one that reccomended rolling the tank to vapor space and rachet strap it stopping the leak. Others suggested plugs. Based on my training and experience, both of these stop the leak. I haven't "seen" this done, I have done it. For real, not a controlled training evolution. I know it works. Venting the tank to atmosphere was also an option but not an acceptable one in my opinion based on the facts given.

    You are correct in no one knows how long it will take to vent out completely but I could probably give you a pretty close estimate.

    In the way I mentioned, the tank eventualy stops venting, much quicker.
    How long will it take to AR?
    Have you actually worked the math on a tank that can potentially AR?
    Will this particular tank AR?

    Basically... Just how long is "eventually" and how do you know it will be "much quicker"?

    Bottom line and last question...

    Will it be quicker, safer and cause less enviromental effect to strap/plug it or AR it?

    And for the record, I disagree with your suggested method. I didn't say you where wrong, I said I felt it was an unacceptable method.

    Be safe, R2

  17. #37
    Forum Member GTRider245's Avatar
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    I cannot give you the math on autorefrigeration. In fact, I can find very little information about it at all on the web. All I can tell you is that I have witnessed it, and it is very fast. Matter of minutes for the tank I saw it performed on. And once it is done, it is done. Time will depend on tank size, but since we already manualy rolled it to the vapor space, I dont see it taking very long.

    AR would not put anyone in harm's way. No personnel are involved. Enviro affects are propane gas leaking into the atmosphere for a few minutes. Since it is already leaking, I don't see this is a huge concern.

    Assuming the tank is AR capable, that is still the route I would take. I wish I could give more info on the process but I simply don't have it. All I know is that I have seen it, and it works. With this concept, seeing is doing, since there is no direct involvment. Anytime you take direct personnel involvment out of the equation, you just made things safer.
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  18. #38
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    Quote Originally Posted by GTRider245 View Post
    I cannot give you the math on autorefrigeration. In fact, I can find very little information about it at all on the web. All I can tell you is that I have witnessed it, and it is very fast. Matter of minutes for the tank I saw it performed on. And once it is done, it is done. Time will depend on tank size, but since we already manualy rolled it to the vapor space, I dont see it taking very long.

    AR would not put anyone in harm's way. No personnel are involved. Enviro affects are propane gas leaking into the atmosphere for a few minutes. Since it is already leaking, I don't see this is a huge concern.

    Assuming the tank is AR capable, that is still the route I would take. I wish I could give more info on the process but I simply don't have it. All I know is that I have seen it, and it works. With this concept, seeing is doing, since there is no direct involvment. Anytime you take direct personnel involvment out of the equation, you just made things safer.
    I have Googled and Nexus (and asked around alot to some of the Haz guys around here) and all I came up with was a case study on a lawn crew that had hit the outlet to an unground tank (residential) and it briefly suggested AR. Although I have recently lost a whole lot of reference material (don't get me cryin about it), what I do have access to mentions it as something to be aware but that' it. No tactical advice, etc.

    Basically what I figure behind the math is that in order for propane to not boil, it has to stay below -40F. When the tank shell, the vapour space and the liquid all drops below -40F, it will stop boiling thus no vapor. The moment, the temp rises... it starts boiling again. Exactly what your saying, just thinking "out loud" here.

    At the facility I work in, we have 3 bullets, 2 of which are at least half full of propylene (which is pretty close to propane) and there would be no way I would even suggest we let it release til it AR's mainly because there is no hard data or industry standard to support the theory as we have both discovered Thinking back on a railcar that had a pretty good leak on the valving, the release did not stay constant and it was assumed (I know... real bad word) in the critique that the valve was the cause (for the leak and the changing release rates. It may have been AR induced although there was no icing present on the car (which could be explained by tank design in the shell).

    I don't doubt you for one second it can be done and you have seen it (which that is a class I am going to take, already lining up the funding). Although a few guys I talked with said it was essentially a "magic trick" to impress the students (which based on what good things said here about this instructor I'll leave that opinion to them and form my own) I do believe it's certainly worth looking deeper into. Being able to add another tool to the box is golden.

    I'm am going to shoot the variables to a math genius I know and see if he can put into equation form. If there is a workable equation, we may be able to predict at what point it will happen and then make the blocks/plugs/whatever's. I tried to work it and had to punch myself. Pump ops this ain't LOL.

    If either of us gets more info (or anyone else) let's start another thread on it. We kinda high-jacked this one

    Very good discussion!!!

    Be safe, R2

  19. #39
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    Like you, I searched long and hard and could not come up with any solid info on AR. Most of the hazmat guys around here know some of the concepts, but have never had the chance to expirience it first hand.

    Im glad to hear that you are planning to take one of Gore's classes. It was easily the best hazmat expirience any of the 4 of us had ever had. I plan on going back as soon as I can.

    Like we mentioned before, the thing to remember is that he pretty much wrote the book. When they were doing things with Jacksonville's team in the 70's there was no book to follow. They were the first, so they did things by trial and error until they figured out what worked. They also figured out what didnt work.

    Going to the class will change your hazmat mindset forever. Gore is very adimant that most teams are too cautious and spend too much time deconing and not enough time fixing problems. He isnt real big on decon for most incidents, and the more you listen to him talk the more you realize we really do waste alot of time that could be better well spent.

    Good discussion indeed. I may email Gore myself and see if he could send me some info on this. Better yet I may have my class materials at home.

    Either way, new thread will be started. Sorry for the hijack.
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  20. #40

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    Hi all . I have 24 years of propane experience and the last 8 years I owned my own propane company. The autorefigeration does slow the vaporization down but it never stops. If there is an open hole in a tank, then there is gas coming out- unless the temp is -44. The faster vapor can boil off, the cooler it will get. You ever put rubbing alcohol on your hand and feel the cool? Same thing. It is vaporizing off. The propane vapor will eventually cool off enough it will slow way down. If you have no way to cap the tank -wood dowels and a brass hammer work great- then it will continue to spew vapor-however slow. If you think its over once it slows you are in trouble. Things that make it flare back up could include wind on the tank, rain, sprinklers, ect. If the container heats up the vaporization rate will increase. Ultimately, the container has to be plugged or taken somewhere safe and evacuated.
    Last edited by Vande250; 02-25-2009 at 01:11 AM.

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