Method of decontaminating a metal surface in a nuclear power plant

US11244770B2 · kind B2 · utility

Assignee

• FRAMATOME · FR

Inventors

• Luis Sempere Belda · Erlangen, DE
• Christian Topf · Forchheim, DE

Key dates

• Filing date: Jun 28, 2018
• Grant date: Feb 8, 2022
• Expiry date: Jan 23, 2040

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02E30/30
• WIPO field: Engines, pumps, turbines
• WIPO sector: Mechanical engineering

Abstract

A method of decontaminating a metal surface located on a component within a nuclear plant, in particular within the cooling system of a nuclear power plant, which is covered with a metal oxide layer containing radioactive substances, the method including a decontamination step in which a metal oxide layer pretreated in an oxidation step is contacted with an aqueous solution of an organic acid to dissolve the metal oxide layer, forming a decontamination solution containing the organic acid, metal ions and the radioactive substances, and passing the decontamination solution over an ion exchanger to immobilize metal ions and radioactive substances. An oxidant selected from oxygen, air, hydrogen peroxide and ozone is dosed into the decontamination solution to control the dissolution rate of the metal oxide layer. The method is particularly suitable for large-scale system decontamination and ensures high process stability.