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Heat, Pressure and Equilbrium in two seperate systems

  1. Aug 14, 2015 #1

    I'm having a bit of a problem, and I'm not sure where to put the question.

    So here's a picture

    Steam Equilibrium Pt 1.png
    Sorry about the picture, Tank B should really be half-full of water and steam. Ignore the turbine part.

    I'm trying to create a distillation device and the basic idea I had was to have a boiler that would use a steam generator to heat the boiler. Then add a turbine to the steam generator that would power a dynamo that would power another pump within the cooling tank for the condenser. A self contained system as far as energy is concerned.

    Both tank systems were originally closed, so there was no effective heat exchange between the two systems, other than from the distillation of the vapours from the still itself. The steam generator tank was hot, the condenser tank was cool.

    I had some weird idea that if I created a closed system, by creating different pressure between the two systems I could effectively have two different temperatures, i.e., maintaining a hotter temperature for the steam generator and cooler temperature for the condenser tank. Thus it would remain a kind of closed system with very few parts.

    The question is, all else being equal, will the temperature remain constant in the above system once a certain equilibrium is reached? or, will Tank A be hotter than Tank B?

    What are the conditions for that equilbrium?

    What is the relationship between Heat, Pressure and Temperature?

    I'm sorry if this seems obvious, I just honestly don't even know where to begin with a question like this, as there never seems to be one obvious answer.

    Attached Files:

  2. jcsd
  3. Aug 14, 2015 #2


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    This is a statement that does not fill me with confidence that you should be messing with heated pressurized vessels. Maybe the very first thing you should add to your design is an emergency pressure relief valve. Maybe one on each vessel. But I have a fondness for avoiding human death and dismemberment. Call me a softy.

    It is entirely unclear what you are trying to achieve. You say you want to make a distillation device. Um, ok. Usually such a device is not supposed to be a closed system. You put a mixture in at one place. Then at another place you take out the concentrated component you are interested in, and probably at another the material you are less interested in. So, for example, in distilling petroleum products. (In VERY simplified form.) You put crude oil in here. You boil it. You pull gasoline off here. And you pull all the other stuff off there.

    So why ever do you want a closed system still? That makes no sense.

    Also, if the distillation part is the goal, why would you try to power a turbine off the pressure? Usually the working material in a still is chosen for purposes of producing one or more chemicals at the end. It is not chosen with the idea of making an efficient turbine. If you need to pump things, then provide it with an electric motor to pump. That will probably be more efficient at producing the chemical you want.
  4. Aug 14, 2015 #3


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    "Steam generator" is a ten-dollar term for "boiler". What you are describing is using a boiler to heat another boiler, which is a tad redundant.
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