Antistatic paint for the inner wall of oil storage tanks

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Antistatic paint is mainly used on the inner walls of storage tanks in the petrochemical industry to prevent the accumulation of static electricity. During loading and unloading, the oil moves relative to the tank, which increases the static voltage on the inner wall of the tank. During processes such as flow, filtration, mixing, spraying, injection, flushing, filling, and shaking, oil products can also accumulate static electricity, as the speed at which static charge is generated is higher than the speed at which it leaks away. When the energy released by the discharge of the accumulated static charge exceeds the minimum ignition energy of the combustible mixture, and when the mixture of oil vapor and air in the discharge gap is within the explosive range, combustion and explosion will occur, with consequences that are extremely severe. From the structural analysis of the coating, the static electricity generated by the coating is mainly due to the high surface resistance of the coating material; the static charges produced are difficult to dissipate immediately, and an increasing amount of such charges accumulates over time. To ensure the safety of oil storage tanks, suppress the generation of static electricity, facilitate the discharge of electrical charges, and prevent the accumulation of static charge, conductive paint can be used on the inner walls of these tanks; the volume resistivity of such coatings should be below 108, and their surface resistivity should be below 109. The main types of antistatic paints are epoxy and polyurethane types, available in both solvent-based and solvent-free forms. Conductive pigments usually use non-graphite-type conductive mica powder.