The U.S. Advanced Fuel Cycle Initiative (AFCI) is a program to develop economic and environmental methods to reduce the impact of waste from commercial nuclear fuel cycles. One concept for near-complete destruction of waste isotopes from used nuclear fuel is acceleratordriven transmutation. High-power accelerators would be used to produce high-energy charged particles, which then collide with heavy metal targets to create a cascade of neutrons. These neutrons then cause a nuclear chain reaction in subcritical systems. Fission neutrons then transmute fissile waste isotopes as well as other problematic isotopes such as technetium-99 and iodine-129. To design these systems, complex reactor physics computer codes and highly detailed data libraries are used to compute the reactivity of systems, reaction rates, destruction rates, and nuclear-induced damage rates to materials. In this project, we will use a Russian-built detector system to make measurements of neutrons generated in a central target by a variety of accelerators. We will also use the most advanced high-energy radiation transport code, MCNPX, to model the experiments. Experimental results will be compared to computational predictions and discrepancies will be investigated. We will conduct experiments using a 70-MeV proton cyclotron at the Crocker Nuclear Laboratory at the University of California at Davis and/or a 20 to 40 MeV electron linac (linear accelerator) at the Idaho Accelerator Center (IAC) at Idaho State University (ISU). Finally, we will use the 800-MeV linac at the Los Alamos Neutron Science Center at Los Alamos National Laboratory.
The NMDS was used in conjunction with an accelerator at the IAC to determine it’s performance. This involved disassembling the system, packing it in its shipping crates, transporting it to ISU, reassembling it, and conducting a series of accelerator-driven experiments. After the experiments were completed, the system was returned to UNLV and reassembled there.
Accelerator-driven systems; Particle accelerators; Radioactive wastes — Transmutation; Spent reactor fuels
Nuclear | Nuclear Engineering | Oil, Gas, and Energy
Neutron Multiplicity Measurements for the AFCI Program Quarterly Progress Report June-August 2004.
Available at: https://digitalscholarship.unlv.edu/hrc_trp_sciences_physics/2