Present status and development of the Romanian nuclear fuel project

The paper describes the main steps of development of the nuclear fuel project for power reactors now under construction in Romania. After a brief review of Phase A of the project, the subsequent phases are dealt with in detail. The pilot plant (Phase B) was commissioned at the Institute for Nuclear Power Reactors (INPR) Pitesti for solving specific problems such as: verifying the fuel manufacturing capability on industrial-scale equipment; qualification of the technology; obtaining the experimental data necessary for the design of production plants; and fabrication of fuel rods and bundles to be tested. These targets were already reached during a few years' operation of the pilot plant. Technological processes for ceramic grade UO2 powder, for UO2 sintered pellets and for fuel bundles were established. At the same time, experience was acquired in the implementation of a proper system to achieve fundamental knowledge, design and testing of nuclear fuel. Efforts were initially focused towards establishing appropriate technical specifications for materials and experimental methods for materials characterization. An important objective was the development of computer codes for simulating the behaviour of fuel elements. This was done mainly by implementing models from literature. A test programme was established to check the behaviour of the fuel elements in-pile and out-of-pile. Most of these tests simulate the operational conditions in power reactors. The testing activities are supported by parallel programmes for the development of testing equipment such as fuel loops for irradiation, out-of-pile test stands, etc. It is assumed that the test results will provide the necessary support for qualification of the fuel element design and for beginning fuel fabrication on an industrial scale (Phase C of the project)