This document summarizes the main outcomes of the Task 4.1 activities concerning the “Core design and simulation” defined in the Project Agreement between ENEA and Transmutex (TMX). The main purposes of the Task were to identify: • the fuel cycle performances aimed for the “Subcritical Transmutation Accelerated Reactor using Thorium” (START) system and the corresponding equilibrium fuel composition; • the definition of the start-up core and its evolution towards the equilibrium core. By foreseeing the Accelerator-Driven System (ADS) operating in the ALFRED (Advanced Lead-cooled Fast Reactor European Demonstrator) thermal conditions (i.e., same FA design and average core temperatures) and considering the related technological constraints (e.g., maximum fuel/clad temperatures, maximum fuel burnup), the actual fuel cycle capabilities were evaluated for several core configurations with different fissile lengths. Selecting the “dirty” Pu burner as fuel cycle option, the perimeter of the viable region in the “operational space” was established. Among the constraints, the maximum proton current range (≈ 3 ÷ 5 mA) allowed for the 800 MeV proton accelerator (and spallation modules designed by TMX) and the minimum irradiation sub-cycle of one year represent the parameters limiting majorly the START viable region. Even if more accurate neutronic analyses will be carried out during Task 4.2 (especially for what concerns the external source term due to spallation neutrons), the required performances seem to be fulfilled by a 300 MW core having an average Pu enrichment of about 24% and a 99 cm fissile length, that guarantees a Pu burning rate of 9.7 kg/TWh in a 5-years fuel cycle, in which the maximum burnup reached is 86 MWd/kgHM.
Deliverable D4.1 – START potential for fuel cycle services and options for START start-up core
Sarotto, M
2022-01-01
Abstract
This document summarizes the main outcomes of the Task 4.1 activities concerning the “Core design and simulation” defined in the Project Agreement between ENEA and Transmutex (TMX). The main purposes of the Task were to identify: • the fuel cycle performances aimed for the “Subcritical Transmutation Accelerated Reactor using Thorium” (START) system and the corresponding equilibrium fuel composition; • the definition of the start-up core and its evolution towards the equilibrium core. By foreseeing the Accelerator-Driven System (ADS) operating in the ALFRED (Advanced Lead-cooled Fast Reactor European Demonstrator) thermal conditions (i.e., same FA design and average core temperatures) and considering the related technological constraints (e.g., maximum fuel/clad temperatures, maximum fuel burnup), the actual fuel cycle capabilities were evaluated for several core configurations with different fissile lengths. Selecting the “dirty” Pu burner as fuel cycle option, the perimeter of the viable region in the “operational space” was established. Among the constraints, the maximum proton current range (≈ 3 ÷ 5 mA) allowed for the 800 MeV proton accelerator (and spallation modules designed by TMX) and the minimum irradiation sub-cycle of one year represent the parameters limiting majorly the START viable region. Even if more accurate neutronic analyses will be carried out during Task 4.2 (especially for what concerns the external source term due to spallation neutrons), the required performances seem to be fulfilled by a 300 MW core having an average Pu enrichment of about 24% and a 99 cm fissile length, that guarantees a Pu burning rate of 9.7 kg/TWh in a 5-years fuel cycle, in which the maximum burnup reached is 86 MWd/kgHM.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
