Pumping fluid w/o fluid going through pump head - any method possible?

Discussion in 'Physics' started by RogueRose, Sep 4, 2016.

  1. RogueRose

    Thread Starter Member

    Oct 10, 2014
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    I'm curious if there are any ways to pump a fluid without the fluid going through the pump head. The reason(s) for this is the fluid could be corrosive to the pump or the temperature is too extreme for the pump. In this case the fluid is used to either cool or heat something.

    In the ideal situation where the pump can handle the extreme conditions, the fluid would be pumped into the chiller and then through the piping that cools the equipment (say motors or transformers) and then back to the motor and into the cooler again. In thecase I'm workign with the fluid starts very cold (and probably corrosive) so the pump has to deal with that

    Option 1 - gravity - The cooled fluid is stored in a vessel, say 5 gal drum and on the other end is a receiving 5g drum - both have a vent hole to allow the ingress and egress of air. The container holding the flid is raised to the height needed for the flow rate required and then reversed when flow is complete. AS it flows from one vessel to vessel it passes through the cooling coil around the equipment.

    Option 2 - similar to above but both 5gal containers have a diaphram where either fluid or air can be pumped in . As the diaphram expands, the fluid in the container is pumped out. This is pretty much how water pressure works in houses with wells, the water storage tank is filled and the diaphram creates the water pressure.

    Are there any other methods that may be used to pump a liquid without it going through the pump head?
     
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  2. djsfantasi

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  3. tcmtech

    Well-Known Member

    Nov 4, 2013
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    Us knowing what the fluid is and what temperature it is at would help.

    As for corrosiveness there are pumps that handle fluids with PH values of o and 14 which are the limits of how basic or acidic a substance can get.

    As for heat there are pumps that pump liquid salts at over 3000 F which I suspect is way beyond what your 5 gallon buckets will handle. :rolleyes:
     
  4. RogueRose

    Thread Starter Member

    Oct 10, 2014
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    Liquid salts would obviously not work with a plastic bucket but some of the 5g SS drums I have would work with some. That's not really the issue though as that is way out of the parameters I need.

    Low temp would be -110F but possibly down to -170 but that would be improbable as it would require much more preparation on setup. The liquids would be isopropyl, ethyl or methyl alcohol and maybe a mix of ethylene and propylene glycol. Calcium Chloride solutions may be used in conjunction with an alcohol to increase density of the fluid to allow for more cooling per flow rate.

    I think pH will be +/- 2 from a neutral 7.

    If this is used for pumping hot fluids it will be oils, mainly vegetable oils & animal fats at an upper temp of 350F but would focus more on the area of 150-200F. I think pH for these oils/fats usually ranges at 5 - 5.5.

    Lastly a super saturated solution of KCl (potassium chloride) and water. Max temp would be 212 (although I might try 2ATM giving about 245-250F..)

    The piping/tubing used would be SS or copper depending on application and insulated. IDK what tubing can be used with the peristatic pump but that is an excellent idea for other applications I am looking at.
     
  5. hp1729

    Well-Known Member

    Nov 23, 2015
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    What is the container and tubing made of? Can't the pump be made of this material? Stainless steel you said. No problem making a pump out of that.
     
  6. hp1729

    Well-Known Member

    Nov 23, 2015
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    Silicon tubing? Typical rated temperature and pressure is about 70 deg F at 5 PSI, bursting at 15 PSI.
    I don't remember him stating a pressure.
    .
     
  7. hp1729

    Well-Known Member

    Nov 23, 2015
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    Is pressure a factor? Is viscosity of the fluid a factor? Required liters per second?
    How hot does cooking oil get? No problems finding pump for that.
    The less specific you are about what youer needs are the less anybody can help you.
    -170 deg are we looking at a cryo pump?
    We play 20 Questions before we can help.
    + or - 2 pH would not seem to be much of a problem.
     
    Last edited: Sep 5, 2016
  8. wayneh

    Expert

    Sep 9, 2010
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    Conventional industrial pumps handle these sorts of things all the time. I haven't heard anything unusual except the cold temperature, which would create challenges. Ambient moisture freezing on the pump is one, seal lubricant is another. You'll need explosion proofing since you have flammable solvents.
     
  9. tcmtech

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    Nov 4, 2013
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    Hmm. this sounds like a list for making biodiesel except for the cryogenic aspects.

    If so I would just use a common hydraulic gear pump or agricultural roller pump for the oil/heavy hydrocarbon fluids and a separate brass pump for the alcohols and a third stainless steel or high nickel content agricultural roller pump heavy base stock.

    As for the cryogenic part I have no clue without knowing the what and why of that part of the system.

    My first suggestion would be a solid brass cryogenics gear, rotary vane or roller pump like what is used for liquid oxygen nitrogen and other cryo fluid transfer systems that has teflon seals.

    Considerably more information on what the whole concept is for would be much helpful assuming this isn't all just an exercise in fanciful dreaming. :rolleyes:
     
  10. Mark Hughes

    Member

    Jun 14, 2016
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    Depending on other circumstances, you could try a Venturi Pump

    But my question is why are you looking for an all-in-one pump? You're not using the cold stuff at the same time you're using the hot stuff, so why not two different pumps?
     
  11. RogueRose

    Thread Starter Member

    Oct 10, 2014
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    Well the pump needs to handle very cold temps when pumping some chilled alcohols and other similar substances as the circulation for a cooling system. The pump will also need to move basically the same volume/pressures of higher temp liquids in another application. The reason is some of these items are pretty expensive and if there was one material that could handle both that was at an attainable price, that would solve the problem. I'm wondering about looking into PTFE coatings (>.5mm thick not mils) but am not sure how it works in cold temps.
     
  12. GopherT

    AAC Fanatic!

    Nov 23, 2012
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    316L or 310 stainless works just fine down to liquid nitrogen temps. The right Seals are the key to success.

    Chloride stress corrosion will eventually be an issue if chloride solutions will be in regular contact. Try a nitrate or nitrite salt instead.

    Ps, if you add alcohol to CaCl2 solution, the salt will precipitate.

    PSS: how do you plan on preventing the SUPER saturated solution of KCl from precipitating while you are pumping it? What's wrong with a simple saturated solution of KCl?
     
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