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Electrostatic precipitators to capture diesel pollution?

  1. Jul 22, 2016 #1
    I would like to understand if someone has tried/or atleast if its feasible to make a Electrostatic precipitators that captures automotive pollution from sources like this?

    Does the physics allow to do that?

    Last edited: Jul 22, 2016
  2. jcsd
  3. Jul 22, 2016 #2


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    ESP? What's that? Google says extrasensory perception. I doubt that is what you mean.

    Edit: I see in the title that you mean electrostaic precipitator. Sorry.
  4. Jul 22, 2016 #3
    Alright edited! :)
  5. Jul 23, 2016 #4


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    The Physics is OK, I think. The problem would be the massive volume that the device would take up in a motor car, in order to deal with the vast amount of particulates without restricting the rate of flow of the gases.
  6. Jul 23, 2016 #5


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    It should not be necessary to use an exhaust filter. Black particles are produced only when incomplete combustion occurs.
    There are several causes of incomplete combustion.
    1. Cold engine or faulty glow plug. Fuel condenses on cold wall then burns slowly.
    2. Blocked air filter. Insufficient air to burn all the fuel injected.
    3. Faulty injector. Dribbles rather than atomises the fuel.
    4. Blocked fuel filter or low fuel. Injection pump spits rather than atomises the fuel.
    5. Insufficient compression of air in cylinder. Failure of cylinder seals or turbo charger.
    6. Too rich fuel. Maximum fuel setting on the injection pump is too high for the fuel being used.

    Black smoke is an indication of a failure. Fix that fault and you will not need a particle filter.
  7. Jul 23, 2016 #6


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    But there is always the problem of particulates (despite what VW try to tell us) and they could be extracted with enough effort (and wasted engine power, I guess).
  8. Jul 23, 2016 #7


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    Older diesel engines with jerk pump injection are progressively being replaced by more efficient and cleaner diesel engines. It is hard to realise how significantly things have improved unless you drive an old diesel tractor or see an old diesel truck blowing black smoke.

    The problem with particulates has been rapidly reduced as common-rail injection systems have been improved. Common rail systems permit accurate computer control of injection timing and fuel volume. https://en.wikipedia.org/wiki/Common_rail

    An electrostatic precipitator would have problems with carbon particles as they would tend to short circuit the high voltage. If a filter was now needed it might be better to use a HEPA filter once the engine reached operating temperature.
  9. Jul 24, 2016 #8

    jim hardy

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    or a gearhead has "performance tuned" his electronic engine control unit
  10. Jul 24, 2016 #9
    I agree to the above points that the technology is improving in a way that emissions can be fixed via repairs, upgrades. However, Particulate matter is the biggest cause of pollution in developing/thirdworld countries where 70% world population lives. The problem is- people don't maintain their cars.

    My question technically is about miniaturizing ESP in a way that it can be retrofit behind vehicles who don't take their vehicles for repairs. Whether you maintain your engines- atleast you'll not pollute the environment.

    Since HEPA is purely mechanical, it would have back-pressure on the engines. Right?

    I am planning on running two experiments next week, and happy to report updates.
  11. Jul 26, 2016 #10


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    As does a turbocharger.
    A centrifugal vortex separator might make a better filter. Could you integrate the separator into the turbine of the charger.

    An inventor needs a cause. “Particulate matter is the biggest cause of pollution … ”. But that does not justify making things more complex and more expensive. Expensive new vehicles prevent the replacement of older polluting vehicles. So you may be better reducing the complexity and cost of new vehicles, to better reduce particulate pollution. Are you considering a compulsory retro-fit of ESP to older vehicles or only on new vehicles ?

    Any filter system added to an existing diesel will have problems during a cold start. How will the ESP system be cleaned. Will it have a recirculating mechanism. How will the carbon be removed from the ESP? Might safe disposal be as an oil or water paste? Could that be recycled somehow? It cannot go through the fuel injection system because of the carbon particles.

    Catalytic converters work for high temperature exhaust but not well for diesel. They are ignored when they fail and are sometimes removed. What makes you think an ESP would be treated differently and maintained by vehicle owners?
  12. Mar 29, 2017 #11
    Any update on your experiments??
  13. Apr 5, 2017 #12


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    Modern Diesel cars (in Europe at least) are fitted with particulate filters and NOx after-treatment.
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