Abstract
This master’s thesis explores how to minimize the long-lived actinide waste that is produced in nuclear power plants by performing simulations of thoriated nuclear fuels in existing reactor designs.
An European pressurized water reactor (EPR) assembly fueled with a mixture of thorium and highly enriched uranium (20% and 90% 235U) was simulated. The spent thoriated fuel is less active, and for a much shorter period of time, than uranium or uranium/plutonium fuels and less decay heat is generated from the waste. Nuclear waste from the thorium cycle can therefore be stored in much smaller repositories than conventional fuels, providing an economical as well as an environmental gain. Also, there will be a substantial net production of fissile 233U, and this makes the multi-recycling of uranium possible; hence significantly lowering the costs of fresh enriched uranium to blend with the recycled fuel.