28th Symposium of AER on VVER Reactor Physics and Reactor Safety (2018, Olomouc, Czechia)
Fuel management issues
Yu. Vergazov, A.V. Ugryumov, A.B. Dolgov, A.I. Shaulskaya (JSC TVEL); Yu.M. Semchenkov, E.K. Kosourov, A.I. Osadchiy, A.M. Pavlovichev (NRC «Kurchatov Institute»)
In accordance with the program of The State Atomic Energy Corporation ROSATOM for reducing the cost of electrical power generation at the stages of operation, design and construction of NPPs with VVER, JSC TVEL has carried out a technical and economic study with the involvement of the National Research Centre “Kurchatov Institute” in the use of nuclear fuel enriched above the current limit of 5 % for VVER-1000/1200. Based on the work done, the following conclusions have been drawn:
1) for manufacturing of pilot fuel assembly based on uranium-erbium fuel enriched above the limit of 5 % it is required insignificant upgrade of equipment for transportation and storage of fresh and spent nuclear fuel;
2) confirmed the possibility of radiochemical processing of nuclear fuel enriched above 5 % using existing facilities and those that are under construction in the Russian Federation for processing spent nuclear fuel of VVER-1000;
3) due to reduction in the number of fresh loaded fuel assemblies in fuel cycles with an increased interval of operation between reloads (more than 18 months):
• increase in the natural uranium consumption for the full operational lifetime of the power unit is not required;
• increase in separative work unit for the full operational lifetime of the power unit is not required;
• the volume of spent nuclear fuel is decreased;
• time of loading/discharge and transportation of fresh and spent nuclear fuel is reduced.
Moreover, the use of fuel enriched above 5 % will allow eliminate the significant disadvantage of non-zirconium claddings for the tolerant fuel that is the decrease in multiplying properties due to neutron capture. Increased fuel enrichment margin will make possible to increase the multiplication factor of the tolerant fuel with non-zirconium claddings.