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Hcl charcteristics - gases recovery

  1. Aug 2, 2006 #1
    Hello, I work on a project on the recovery of gases HCl 33 % which escape during the load of this last one in tanks. I want to know if you can help me or propose me a solution for the calculation of this quantity and if you have an idea of a method to get back them. or any information about the evaporation of HCl during loading.
    thank you very much
     
  2. jcsd
  3. Aug 2, 2006 #2
    I'm not quite sure what you mean by 'the load of this last one in tanks'.
    Are you talking about static storage tank, or trucks?

    I also use HCl in my plant. And I'm still not sure whether it is economical to try to recover the HCl lost due to evaporation.
     
  4. Aug 3, 2006 #3
    i'm talking about storage in static tanks and transportation by trucks.
    it's economical? well, it depends on how much costs HCl in your region, and the cost of the recovering plant conceived?
    do you have any idea how can i measure or calculate these losses?
     
  5. Aug 3, 2006 #4
    No, unfortunately, I don't know how to calculate it :frown: .

    Do you have any idea yet on how to recover the gaseous HCl?
     
  6. Aug 4, 2006 #5
    there are many ideas depending on the process you're using, but the main key , i think, is to try to emerge the gases in water and wait untill its concentration reach the amount you want before recycling it
     
  7. Aug 5, 2006 #6
    yeah, I had the same idea also. But I haven't got the chance to put the idea into work.
     
  8. Aug 5, 2006 #7

    Gokul43201

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    Edit: bigufo, please do not double-post.
     
    Last edited: Aug 5, 2006
  9. Aug 5, 2006 #8
    Gufo:

    Can you please clarify what loss you are talking about?? Are you talking about losses from the tank truck vents while loading into the tank truck from your storage tanks? If so, have you thought of simply venting the trucks back into your storage tanks?

    Milt Beychok
    (Visit me at www.air-dispersion.com)
     
  10. Aug 7, 2006 #9
    mbeychok
    yes, that's right it's about losses from the tank truck vents while loading the solution into it from the storage tanks, but i can't simply vent the trucks back into the storage tanks because the losses are gases and it will increase the pressure into the storage tank.
     
  11. Aug 7, 2006 #10
    hi mbeychok, do you know how can i quantify or measure these losses?
     
  12. Aug 7, 2006 #11
    Bigufo:

    As you pump out of the storage tank into the truck:

    (1) The the liquid level in the storage tank is lowered and hence the larger vapor space is filled by inflow of ambient air through the tank vent.

    (2) As you pump into the truck, the level rises and "pushes" vapor out of the truck vents. If you connect a hose from the truck vents back to the storage tank, the vapor pushed out of the truck would flow into the storage tank. It would not raise the pressure in the tank by any signicant amount.

    Milton Beychok
    (Visit me at www.air-dispersion.com)
     
  13. Aug 8, 2006 #12
    mbeychok:
    if the pressure would not increase in the storage tank it's because of its vent. so if i connect a hose from the truck vent back to the storage tank the HCl vapor will escape through the storage tank's vent.
    "As you pump into the truck, the level rises and "pushes" vapor out of the truck vent" : i am not talking about the vapor that already filled the truck before loading. it's about the vapor that is generated by diffusion and evaporation of the solution, and it's this quantity that i need to quantify.
     
  14. Aug 8, 2006 #13
    mbeychok:
    if the pressure would not increase in the storage tank it's because of its vent. so if i connect a hose from the truck vent back to the storage tank the HCl vapor will escape through the storage tank's vent.
    "As you pump into the truck, the level rises and "pushes" vapor out of the truck vent" : i am not talking about the vapor that already filled the truck before loading. it's about the vapor that is generated by diffusion and evaporation of the solution, and it's this quantity that i need to quantify.
     
  15. Aug 8, 2006 #14
    Bigufo:

    I am talking about the vapor from the truck vent being routed into the tank vent for the duration of the loading. Or install a piping tee on the vent line with a valve on each branch of the tee. When loading a tank truck, close the valve on the branch that normally vents the tank and open the valve on the branch to which the vapor return hose is connnected.

    The vapor return line I am suggesting is commonly called a "vapor balance line". In the United States, such vapor balance lines are required by law (in most of our States) when loading volatile liquids into tank trucks or rail tank cars. It is well-established technology.

    The gases returned from the truck to the tank would be vapors that were in the truck prior to loading as well as any vapors generated during loading.

    Milt Beychok
    (Visit me at www.air-dispersion.com)
     
  16. Aug 9, 2006 #15
    thank you very much mbeychok, you were really very helpful.
     
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