What is passivation ?
Forming a thin film coat inside the equipment by circulation of different chemicals through the equipment is known as passivation. It forms a film in microns over surface which is Descaled & Neutralized. It prevents further corrosion of the treated surfaces. Why the passivation is necessary?
After descaling & the neutralizing procedure, passivation is essential for any vessel or the equipment. It is essential that the residual acid attack on the surface should be properly neutralised & properly quoted by applying a suitable solution, before applying the equipment back in service. Following cleaning with an acid, rinsing with water & neutralizing, the highly reactive surface tends to flush rust. The formation of this type of ferric acids can be prevented by adding some organic agents to the passivation chemicals. These organised agents form very stable complexes with Ferric Iron & thus prevent the formation of rust without interfering with the development of the Passivating film of Fe2O3