The role of corrosion inhibition in the mitigation of CaCO3 scaling on steel surface

Corrosion-induced CaCO3 scaling is extremely widespread at metal/water interface. However, the anti-scale and anti-corrosion behaviour of existing inhibitors have mostly been investigated separately without considering their interaction. Herein, the roles of corrosion inhibition in mitigating interfacial scaling were evaluated on carbon steel and stainless steel by introducing NaNO2 to enhance their corrosion resistance. Results reveal that corrosion-induced pH increase at micro cathodes dominates the interfacial scaling processes by inducing rapid nucleation. A temperature elevation promotes interfacial scaling mainly through aggravating steel corrosion. Once the micro cathodic processes are inhibited, CaCO3 scaling can be evidently retarded even at elevated temperatures.