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First, let’s look at the causes of static electricity: all matter is composed of atoms, and the basic structure of an atom consists of protons, neutrons, and electrons. We define protons as having a positive charge, neutrons as being charge-free, and electrons as having a negative charge. Under normal conditions, an atom has the same number of protons as electrons, resulting in a balance between positive and negative charges; therefore, it appears electrically neutral. However, external influences such as friction or the action of various forms of energy like kinetic energy, potential energy, thermal energy, chemical energy, etc., can cause an imbalance in the positive and negative charges of atoms. Friction, as it is referred to in daily life, is essentially a process of continuous contact and separation. In some cases, static electricity can be generated without friction, such as through induction, thermoelectric and piezoelectric effects, the Helmholtz layer, and jet charging. Static electricity can be generated whenever two objects made of different materials come into contact and then separate ; The origin of the hazards caused by static electricity: Static electricity accumulates when the rate at which it is generated exceeds the rate at which it dissipates. In flammable and explosive environments, a discharge resulting from this accumulation of static electricity can generate static sparks that lead to fires or explosions ; Or the accumulated static electricity can cause hazards such as interfering with the proper operation of instruments and equipment ; Whether static electricity will accumulate: The definition of a static-electricity conductor is a material with a conductivity of 100 PS/m or higher, while a conductive liquid is defined as one with a conductivity of 104 PS/m or higher. The significance of this is that the rate at which static electricity dissipates in such fluids is greater than the rate at which it is generated, meaning that no static electricity accumulation occurs ; Standard GB 13348 requires that antistatic additives be added to oils to prevent static electricity buildup, stipulating only that their conductivity must be no less than 250 PS/m ; The conductivity of pure water is approximately 547 PS/m; generally, the more impurities are present in water, the higher its conductivity and the stronger its ability to conduct electricity ; Based on the above, the circulating water, fresh water, and desalinated water pipelines do not require electrostatic grounding. I hope the experts will share their opinions.
I agree with you; we haven’t installed either static grounding or static bonding either.
I noticed that some process engineers work in a rather careless manner; in the pipe naming table, for all pipes, regardless of the medium they carry, a check mark is placed in the static grounding column
After all, when you see dozens of pipeline condition tables, no one can go through them one by one; moreover, on-site, such situations are usually ignored as they are minor issues
Circulating water, fresh water, and desalinated water pipelines do not require static grounding.
Is your air, nitrogen, and instrument air grounded?
If it is within the explosion hazard area, I think grounding should be done. Although these gases are non-toxic, non-flammable, and non-corrosive, they can cause static electricity to accumulate, which may lead to static sparks that ignite other flammable materials.