Copper grounding electrodes should not be used for storage tank grounding

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Corrosion prevention measures: A certain thickness of brine always accumulates at the bottom of crude oil storage tanks. When storing heavy oils or those with high sulfur content and acid values, higher requirements are placed on corrosion protection. Although there is currently no unified standard for the anti-corrosion design of storage tanks, for large crude oil storage tanks with huge storage capacities and high corrosivity, the importance of thoroughly designing and implementing anti-corrosion measures is self-evident. 1. Corrosion protection for the outer wall of the tank bottom: In addition to applying conventional external corrosion protection coatings to this area, it is advisable to follow the petroleum and natural gas industry standard SY/T0088-95 \"Technical Standards for Cathodic Protection of the Outer Wall of Steel Storage Tanks.\" Sacrificial anodes or forced-current cathodic protection methods can be used; such anodes can also serve as lightning and static discharge protection electrodes for the tank. It is important to note that the traditional copper grounding electrode must be replaced – as copper acts as the cathode in this case, while the steel of the tank becomes the anode, thereby accelerating corrosion. It is advisable to use zinc or magnesium electrodes instead. 2. Corrosion protection for the inner wall of the tank bottom: Even when coating protection is used, it is still necessary to consider the use of sacrificial anodes depending on the circumstances, in order to reduce corrosion in case of defects in the coating. Electroconductive anti-corrosion coatings must never be used for coating, as using them in combination with a sacrificial anode will accelerate the dissolution of the anode, thereby rendering its cathodic protection function ineffective. Aluminum (Al)-based alloy anodes are suitable as sacrificial anodes for the inner wall.