Title: Chemical kinetics parameters of nuclear graphite gasification

Authors: Mohamed S. El-Genk; Jean-Michel P. Tournier

Addresses: Institute for Space & Nuclear Power Studies, Chemical & Nuclear Engineering Department, Mechanical Engineering Department, University of New Mexico, Albuquerque, NM, USA ' Institute for Space & Nuclear Power Studies, Chemical & Nuclear Engineering Department, University of New Mexico, Albuquerque, NM, USA

Abstract: This paper provides chemical kinetics parameters for the gasification of nuclear graphite grades of IG-110, IG-430, NBG-18 and NBG-25 and presents empirical correlations for their surface areas of free active sites as a function of mass. The kinetics parameters for the four elementary chemical reactions of gasification of these grades of nuclear graphite include the values and Gaussian distributions of the specific activation energies and the values of the pre-exponential rate coefficients for the adsorption of oxygen and desorption of CO and CO₂ gases. The values of these parameters and the surface area of free active sites for IG-110 and NB-25, with fine and medium petroleum coke filler particles, are nearly the same, but slightly different from those of NBG-18 and IG-430, with medium and fine coal tar pitch coke filler particles. Recommended parameters are applicable to future safety analysis of high and very high temperature gas cooled reactors in the unlikely event of a massive air ingress accident.

Keywords: nuclear graphite gasification; chemical reaction kinetics; high temperature nuclear reactors; very high temperature nuclear reactors; air ingress accidents; safety analysis; nuclear safety; nuclear energy; nuclear power; nuclear accidents; gas cooled reactors.

DOI: 10.1504/IJNEST.2013.052169

International Journal of Nuclear Energy Science and Technology, 2013 Vol.7 No.3, pp.258 - 284

Received: 22 Feb 2012
Accepted: 21 Aug 2012
Published online: 20 Sep 2014 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article