Applying Film-Forming Amines for Rendering Corrosion Resistance to Structural Materials of Equipment and Piping of Power Units at Nuclear Power Plants (NPP) (Review)

Current issues are examined whose solution could help to assess the effect of film-forming amines, in particular octadecylamine (ODA), on the corrosion state of thermal and mechanical equipment and piping of nuclear power plants and thereby accelerate the introduction of these technologies at nuclear power plants. The application of film-forming amines (FFA), film-forming amine products (FFAPs), and film-forming substances (FFS) has been demonstrated to be an innovative technology designed to minimize the corrosion rate of structural materials and reduce the intensity of deposit formation in the steam-water path of power units at nuclear power plants. In recent years, along with the increased interest in FFAs and FFAPs and the achieved positive results of their use, certain negative phenomena have been observed that caused the suspension of the introduction of the FFA/FFAPs technology at domestic nuclear power plants. The special aspects are examined of the results of pilot operation of the regimes with dosing ODA to the secondary circuit of power units at NPPs in Russia and abroad. Facts are presented demonstrating that many issues concerning the technologies for application of ODA and other FFAs at nuclear power plants are still open and require additional studies for their solution. Proposals are formulated that may be employed to obtain the missing data, which make it possible to assess the effect of FFAs on the corrosion condition of equipment and piping of nuclear power units and improve understanding of the FFA technology with regard to the description of the main fundamental processes occurring on dosing these chemicals to the NPP steam-water circuit.