The Paton Welding Journal, 2011, №07



2011 №07 (05)

2011 №07 (07)

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The Paton Welding Journal, 2011, #7, 26-29 pages  

¹³⁷Cs AND ⁹⁰Sr PHASE TRANSITIONS IN SURFACING OF RADIOACTIVELY CONTAMINATED METAL STRUCTURES

A.A. ENNAN¹, S.A. KIRO¹, M.V. OPRYA¹, V.E. KHAN², B.I. OGORODNIKOV², V.A. KRASNOV², A. de MEYER-VOROBETS³, L. DARCHUK³ and B. HOREMENCE³

¹Physical-Chemical Institute for Environmental and Human Protection, NASU, Odessa, Ukraine
²Institute for Problems of Nuclear Power Plants Safety, NASU, Chernobyl, Ukraine
³University of Antwerp, Antwerp, Belgium
 
 
Abstract
The paper presents the results of investigation of phase transitions of ¹³⁷Cs and ⁹⁰Sr radionuclides from the surface of contaminated metal structures into the solid component of welding aerosol (SCWA), slag crust and deposited metal in metal surfacing with stick electrodes. It is shown that SCWA radioactivity is due to adsorption of thermolysis products of Cs₂CO₃ (Cs₂O, Cs₂O₂, Cs), slag (its contamination by ⁹⁰Sr and ¹³⁷Cs), deposited metal surface (formation of cesium monoferrite (CsFeO₂) and/or polyferrites (Cs₂O.6Fe₂O₃ and CsFe₁₁O₁₇)). The established empirical dependence of specific activity of ¹³⁷Cs in SCWA composition on ¹³⁷Cs surface activity can be used in forecasting the radioactive contamination or air in the working zone and rating the need for personal protective gear for respiratory organs.
 
 
Keywords: arc surfacing, radioactively contaminated metal structures, welding aerosol, slag crust, deposited metal, activity of ¹³⁷Cs, ⁹⁰Sr radionuclides, phase transitions, object «Ukrytie»
 
 
Received:                ??.??.??
Published:               28.07.11
 
 
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