Neutronic evaluation of a non-fertile fuel for the disposition of weapons-grade plutonium in a boiling water reactor [report]

J.W. Sterbentz
1994 unpublished
A new non-fertile, weapons-grade plutonium oxide fuel concept is developed and evaluated for "deep bum" applications in a boiling water reactor environment using the General Electric 8x8 Advanced Boiling Water Reactor (ABWR) fuel assembly dimensions and pitch. Detailed infinite lattice fuel bumup results and neutronic performance characteristics are given and although p r e h h a r y in nature, clearly demonstrate the fuel's potential as an effective means to expedite the disposition of
more » ... position of plutonium in existing light water reactors. The new non-fertile fuel concept is an all oxide composition containing plutonia, zirconia, calcia, and erbia (Pu02-~-CaO-Er203) having the following design weight percentages: Calcia ((30) 9.7 Rbia @r2@) 1.6 This Pu&-m-CaO-@@ fuel composition in an infinite fuel lattice operating at linear heat generation rates of 6.0 or 12.0 kW/ft per rod can remain critical for up to 1200 and 600 Effective Full Power Days (EFPD), respectively, and achieve a burnup of 7.45 * 1020 Ucc. These bumu s isotope for the 040% moderator steam void condition. Total plutonium destruction greater than 73% is possible with a fuel management scheme that allows subcritical fuel assemblies to be driven by adjacent high reactivity assemblies. The Pu@-m-CaO-@@ fuel exhibits very favorable neutron characteristics from beginningof-life POL) to end-of-life (EOL). Prompt fuel Doppler coefficients of reactivity are negative, with values ranging between -0.4 to -2.0 pcm/K over the temperature range of 900 to 2200 K. Steam void coefficients of reactivity are also negative, ranging between -0.1 to -0.5 over the 10 to 90% moderator steam void range. Isothermal temperature coefficients are strongly negative at BOL and tend to become less negative with burnup, until near EOL when the coefficients become positive. In addition, despite the relatively low BOL plutonium rod mass concentrations (approximately 132 gjrd Pu metal), the ABWR fuel lattice remains in an undermoderated condition for both hot operational and cold startup conditions over the entire fuel burnup lifetime. correspond to a 71-73% total plutonium isotope destruction and a 91-94% destruction of the B 9Pu . '
doi:10.2172/34308 fatcat:lmvm2fkcyvawtkljq7tj56g5mu