Patent Number: 
Section: claims

1. A method for suppressing corrosion in a pressurized water nuclear plant comprising a secondary system, the secondary system comprising a steam generator, a turbine, a condenser, and a heater and not comprising a deaerator, the method comprising, in the following order:circulating water through the secondary system;depositing a protective substance on a surface of a structural member of the secondary system by spraying or by bringing a fluid comprising TiO2 as the protective substance in contact with the surface of the structural member of the secondary system; and thencirculating water through the secondary system such that the water contacts the protective substance, to make the protective substance into a single layer of TiO2 ,wherein the protective substance consists of a single layer of TiO2. 2. The method of claim 1, wherein the water is circulating water which is not subjected to chemical injection by a chemical injection device. 3. The method of claim 1, wherein the structural member of the secondary system having the protective substance is the steam generator. 4. The method of claim 1, wherein the structural member of the secondary system having the protective substance is the heater.