Electrostatics from particle laden air

AI Thread Summary
Static electricity can indeed be generated from airflow containing particles like smoke or dust, as evidenced by grain transporters and silos where such mixtures can lead to explosive conditions. The discussion explores the potential for adapting devices like the Van de Graaff generator or Kelvin water dropper to harness this effect, though challenges such as particle adhesion and charge repulsion are noted. Tiny metallic particles may be more effective for discharging due to their conductive properties. However, practical experiences highlight the difficulties of managing airborne metallic particulates, which tend to cling to surfaces. Overall, while the concept is intriguing, caution is advised due to the risks associated with static electricity generation in particle-laden environments.
Niki
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Is it possible to generate static electricity from air flow containing particles example smoke or dust flow, or does anyone know of experiments such as the kelvin water dropper converted to generate static from air flow ?

Thanks
 
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It very possible. Grain transporters and silos use air to move grain around. Unfortunately the mixture of dust and air can be explosive and generate sufficient static electricity to trigger an explosion.
 
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Warning - speculation !

I've often wondered if something like this could be used in a Van de Graaff arrangement. But I'd assumed I could just rely on ionising air molecules.

If you used dust, I wonder how you would discharge the particles? When they passed through the mesh / past the brushes, wouldn't they be attracted and tend to stick? Perhaps tiny metallic particles would work better, as they would discharge on contact.

The problem with both VdG and Kelvin generator might be the repulsion as the charge builds up, but with solid particles if you drive them fast enough I suppose you can overcome that (the water drops disintegrate.).
 
Perhaps also worth looking at how the charge needed to create a lightning strike is built up.
 
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Merlin3189 said:
…Perhaps tiny metallic particles would work better, as they would discharge on contact …
DON’T DO IT! I used to work in a robotic welding factory. The air was always a bit hazy, and most of that haze was tiny metallic particulates. I can tell you from experience that they cling to everything. As a maintenance team, it was one of our biggest problems.

Sorry to be so emphatic, but I think I just had a little ptsd flashback.
 
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