Static electricity is the imbalance of electric charges within or on the surface of a material. Static electricity produced due to the following phenomenon.
1. Pressure induced charge separation: Piezoelectric Effect. Applied mechanical stress generates a separation of charge in certain types of crystals and ceramics.
2. Heat induced charge separation: Pyro electric Effect. Heating generates a separation of charge in the atoms or molecules of certain materials. (Example: Hair dryer).
3. Charge induced charge separation: Electrostatic Induction. A charged object brought into the vicinity of an electrically neutral object, will cause a separation of charge within the conductor. Example: Computer boards and electronic components keeping inside the antistatic packing. This packing acts as a Faraday’s cage that surrounds the material inside and keeps charge from entering or leaving from the material.
4. Contact Induced Charge Separation. Electrons can be exchanged between materials on contact. Materials with weakly bond electrons tend to lose them, while material with sparsely filled outer shells tends to gain them. This is known as the triboelectric effect and results in one material becoming positively charged and the other negatively charged. Example: Rubbing different material together causes the static charge to accumulate on the surfaces of materials.
Static electricity presents fire and explosion hazards during the handling of petroleum and other tanker operations such as tank cleaning, dipping, ullaging and sampling. Certain operations can give rise to accumulations of electric charge which may be released suddenly in electrostatic discharges with sufficient energy to ignite flammable hydrocarbon gas/air
mixtures. There is, of course, no risk of ignition unless a flammable mixture is present.
There are three basic stages leading up to a potential static hazard:
1. Charge separation;
2. Charge accumulation; and
3. Electrostatic discharge.
Static Electricity in oil tank, Prevention;
1.Earthing device, earth bond across flanges on pipeline.
2.Inert gas
1. Pressure induced charge separation: Piezoelectric Effect. Applied mechanical stress generates a separation of charge in certain types of crystals and ceramics.
2. Heat induced charge separation: Pyro electric Effect. Heating generates a separation of charge in the atoms or molecules of certain materials. (Example: Hair dryer).
3. Charge induced charge separation: Electrostatic Induction. A charged object brought into the vicinity of an electrically neutral object, will cause a separation of charge within the conductor. Example: Computer boards and electronic components keeping inside the antistatic packing. This packing acts as a Faraday’s cage that surrounds the material inside and keeps charge from entering or leaving from the material.
4. Contact Induced Charge Separation. Electrons can be exchanged between materials on contact. Materials with weakly bond electrons tend to lose them, while material with sparsely filled outer shells tends to gain them. This is known as the triboelectric effect and results in one material becoming positively charged and the other negatively charged. Example: Rubbing different material together causes the static charge to accumulate on the surfaces of materials.
Static electricity presents fire and explosion hazards during the handling of petroleum and other tanker operations such as tank cleaning, dipping, ullaging and sampling. Certain operations can give rise to accumulations of electric charge which may be released suddenly in electrostatic discharges with sufficient energy to ignite flammable hydrocarbon gas/air
mixtures. There is, of course, no risk of ignition unless a flammable mixture is present.
There are three basic stages leading up to a potential static hazard:
1. Charge separation;
2. Charge accumulation; and
3. Electrostatic discharge.
Static Electricity in oil tank, Prevention;
1.Earthing device, earth bond across flanges on pipeline.
2.Inert gas
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