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How to control static electricity in Oil and gas

Bonding and grounding
Prevention There are a number of process improvements that can be put in place to help prevent the likelihood of a fire or explosion caused by static electricity. Reducing the flow rate of liquid is one technique because static electricity increases as the flow of flammables increase. An effective way to do this is by slowing processes down. “Reduce the amount of speed that’s happening when you’re filling, when transferring flammables. Obviously there are operational and economic constraints — no one wants to dribble material from one thing to another — but people need to make that trade-off on their own,”. Slowing processes down also reduces the amount of splashing of the flammable liquid. This is important because static electricity increases as the liquid’s surface area of contact increases. “You can image water splashing in a container; it comes out as a stream and as it hits the bottom, it spreads out across all the surface area that’s given at the bottom of that container, so now you have more surface area contact for the flammable and more electrons are able to transfer,”. Bottom filling a container through a long dip pipe is a generally accepted practice for reducing the amount of splashing. Agitating the liquid less is another useful technique. “You’re going to eliminate some liquid so it won’t be agitated as much or move it without agitating it as much and building up the static electricity,”. Humidity control is another method for reducing the generation of static electricity. A relative humidity of about 50 per cent is sufficient to avoid difficulties with static electricity, according to the National Fire Protection Association. “The less moisture there is in the air, the more static charge can build up because the charge cannot leak off with a lack of moisture, so atmospheric conditions do play a role,”.
Good installation practices to safely discharge static electricity involve bonding and then grounding the conductive equipment that produces static electricity.
 Image result for bonding and grounding      
Bonding means permanently or temporarily joining all metal parts together. This helps keep the bonded objects at the same level of potential energy, eliminating the risk of static sparks between them.
Grounding means establishing a conductive path between a bonded object and the earth. The conductive path to the earth discharges the built-up static electricity to ground.

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