How is corrosion protection done for the bottom plates of storage tanks?

Due to the micropores in the coating layer, cracking and peeling tend to occur after aging. If pinholes occur due to poor construction quality, the exposed metal acts as a small anode, while the coating layer becomes a large cathode, resulting in a local corrosion cell that accelerates the degradation of the paint film. Therefore, using a separate coating does not provide good protection. The combined use of coating and cathodic protection to provide concentrated current protection for exposed metal, thereby compensating for the defects in the coating layer, is the most economical and effective method for preventing corrosion of the bottom plates of storage tanks. The edge plate of the storage tank plays a very important role in the tank structure, but it is prone to water infiltration and thus corrosion. None of the currently in use storage tanks have effective anti-corrosion measures in place. To fully control corrosion of the tank bottom plates, in addition to protecting the main body of these plates, effective anti-corrosion measures must also be taken for the exposed parts of the edge plates (hereinafter, the term \"edge plates\" refers specifically to their exposed parts). Anti-corrosion measures such as filling the gap between the bottom edge plate of the tank and the foundation with asphalt sand are taken.

In fact, many things weren’t done, including the inner walls as well.