Tritium Removal from Codeposits on Carbon Tiles by a Scanning Laser
Authors: C.H. Skinner, C.A. Gentile, A. Carpe, G. Guttadora, S. Langish, K.M. Young, W.M. Shu, and H. Nakamura
Date of PPPL Report: September 2001
Date of Revised PPPL Report: December 2001
Published in: Journal of Nuclear Materials 301 (2002) 98-107.
A novel method for tritium release has been demonstrated on codeposited layers on graphite and carbon-fiber-composite tiles from the Tokamak Fusion Test Reactor (TFTR). A scanning continuous wave Nd laser beam heated the codeposits to a temperature of 1200-2300 degrees C for 10 to 200 milliseconds in an argon atmosphere. The temperature rise of the codeposit was significantly higher than that of the manufactured tile material (e.g., 1770 degrees C cf. 1080 degrees C). A major fraction of tritium was thermally desorbed with minimal change to the surface appearance at a laser intensity of 8 kW/cm2, peak temperatures above 1230 degrees C and heating duration 10-20 milliseconds. In two experiments, 46% and 84% of the total tritium was released during the laser scan. The application of this method for tritium removal from a tokamak reactor appears promising and has significant advantages over oxidative techniques.