The MARIA reactor went critical for first time in December 1974. The reactor was in operation until 1985 when it was shut down for modernization. The modernization consisted in refurbishment and upgrading of technological systems. In particular, the efficiency of ventilation and cooling systems was improved. Since 1993 the MARIA reactor has been in full operation.
The main reactor applications:
In 2010 the reactor completed 31 operation cycles at power from 30 kW to 23 MW and the total operation time of 3803 h. In 2011 and 2012 the total operation time was 4275 h (33 operation cycles) and 4610 h (34 operation cycles), respectively.
In 2010 mainly MR-6 type fuel assemblies with 36% enrichment and 430g contents of U-235 were loaded in the reactor core. During the 2010 and 2011 two prototype, low-enrichment fuel assemblies (MC-5) were tested. These fuel assemblies with 19,75% enrichment and 485g contents of U-235 were fabricated by AREVA. In September 2012 the process of converting the Maria reactor core to low-enriched fuel with enrichment 19,75% in 235U started. This process will be carried out progressively and the highly enriched MR-6 fuel elements will be replaced, one by one, with low enriched fuel MC-5 type.
Neutron irradiation services provided at the MARIA research reactor include radioisotope production, neutron transmutation doping of silicon, neutron activation analyses and biomedical technologies.
The Regional Laboratory of Neutronography (RLN) provides experimental facilities and research experience in the field of thermal neutron scattering studies of condensed matter and materials engineering. The laboratory operates six horizontal channels of the MARIA reactor and six instruments designed for elastic and inelastic neutron scattering.