The Accelerator Transmutation of Waste (ATW) concept overview

The accelerator transmutation of waste (ATW) concept is aimed at destroying key long-lived radionuclides (both actinides and fission products) in nuclear wastes, thereby reducing the long-term risks associated with the storage of such wastes. This technology could evolve into an approach to the production of fission power, utilizing abundant natural fuels and producing minimal long-lived nuclear waste. An ATW system would consist of the following components: 1. proton accelerator; 2. heavy-metal target; 3. moderating blanket; 4. thermal-to-electric power conversion plant; and 5. chemical separation facility. The linear accelerator provides a medium-energy, high-current proton beam that is directed at a heavy-metal target. The target converts the proton beam through spallation reactions into an intense neutron flux that is thermalized in the blanket region surrounding the target. The radioactive material to be transmuted is circulated through the blanket, where it undergoes neutron-induced reactions. Long-lived fission products undergo (n, [gamma]) reactions followed by beta decay, producing short-lived or stable products. The actinides are fissioned, producing additional neutrons and an assortment of fission products to reduce parasitic absorption in the blanket and to prevent further activation of these materials to long-lived radionuclides.