Root causes analyzed of leakage on the tank bottom using simulation cathodic protection

in this paper, cause of leakage on the caustic tank bottom is investigate using simulation cathodic protection and develop the NACE formula “current distribution with a close anode-to-structure spacing”. The Finite Element Method is used for numerical solution. Although, field measurements have been under protection of the tank bottom, However, the simulation results showed that only a limited area of the tank bottom was protected, which this area follows the NACE formula and the surrounding areas of the tank have a lower level of protection, that has led to the leakage this areas. There were many ways to increase the protection area, one of them was an increase the anode distance from the tank bottom that the NACE formula indicating this issue but the simulation results showed the opposite of this. Each anode make a potential gradient that can vary from one anode to another. Therefore, NACE formula can be used until; with increase anode distance from tank bottom, tank bottom don’t get out from anode potential gradient. For this reason, in this paper, the NACE formula has been developed by providing a complementary formula and using the specified condition, which has a higher efficiency than the previous formula.