e.g. transporting charges from one surface to another
Double layer charging
Caused by friction at interfaces on a microscopic scale.
Occurs when an isolated conductor is subject to a electric field. Charges of different polarity are induced on opposite sides. If an earthed electrode touches or approaches the body then the charges closest to electrode flow away leaving the body with a net charge of opposite sign.
Occurs by walking across carpet.
Nonconductive shoes are a problem.
Charging by Transport
Results from a charged dust, liquid or solid particles settling onto a surface and transporting their charges to this new surface.
The rate of charge accumulation is a function of the rate of transportation.
Lightening is an example of this type of charging phenomenon.
Dust Explosion Control
Basic concepts of dust explosions
Accumulation of charges
Deadly Dust II (Video)
Static electric ignitions are the result of transferring the accumulated charges to another surface via a discharge.
The accumulated charge may be safely leaked away to earth by grounding.
If energy of discharge exceeds MIE then fire or explosion.
Static electric Discharges
Conical pile (Maurer)
Discharges between two conductors.
Very energetic with energies ranging up to 10 Joules.