DEACTIVATION METHOD OF NUCLEAR REACTOR PIPELINES Russian patent published in 2010 - IPC G21F9/34 

FIELD: power industry.

SUBSTANCE: deactivation method involves saturation of rigidly fixed radioactive corrosion products with soda solution with concentration of 10-30% during 24-48 hours with further treatment with sulphuric acid solution with concentration of 20-40% during 1-2 hours. Escaping carbon dioxide loosens corrosion products, which allows eliminating the basic mass of activity with water jet. If necessary, there performed is ultrasonic treatment with ultra sound frequency of 18-22 kHz and intensity of 2-3 W/cm² in solution of 2.5% HNO₃, 0.5% H₂C₂O₄, 0.2% Na F, 0.5% of ethylenediamine-tetraacetic acid.

EFFECT: invention makes it possible to destruct and to remove corrosion products together with radioactive impurities from inner surfaces of pipelines of the first circuit of reactors.

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