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Preliminary evaluation of 14C and 36Cl in nuclear waste from Ignalina Nuclear Power Plant decommissioning

“…Major 14 C producing neutron activation reactions in NPP reactors are [21][22][23][24][25]: (a) the 14 N(n, p) 14 C reaction with a very high thermal neutron capture cross-section (1.82 barn (1 barn = 10 -24 cm 2 )); (b) the 17 O(n, α) 14 C reaction with a high thermal neutron capture cross-section (0.24 barn); (c) the 13 C(n, γ) 14 C reaction with a low crosssection (0.9×10 -3 barn); (d) the 15 N(n, d) 14 C reaction with a very low cross-section (2.5×10 -7 barn); (e) the 16 O(n, 3 He) 14 C reaction with a very low cross-section (5.0×10 -8 barn).…”

Management of Radioactive Waste Containing Graphite: Overview of Methods

“…In waste containing radioactive i-graphite, one may also find corrosion and activation products ( 57 Co, 60 Co, 54 Mn, 59 Ni, 63 Ni, 22 Na), fission products ( 134 Cs, 137 Cs, 90 Sr, 152 Eu, 154 Eu, 155 Eu; 144 Ce) and small amounts of uranium and transuranium radionuclides ( 258 Pu, 259 Pu; 241 Am, 243 Am) [23,24]. Even if present in small amounts (usually less than 0.01%), 20-30 years after irradiation, the neutron flux in these impurities may still pose a radiological risk to the environment.…”

The synthesis of graphite–glass composites intended for the immobilisation of waste irradiated graphite

“…Graphite was used in many of the original reactor designs such as the British Magnox reactor and Russian RBMK reactors as a neutron moderator and comprised a considerable volume of the reactor core [1,3]. Many of these reactors have now reached the end of their operational life-span and will require decommissioning, as a result an estimated 250,000 tonnes of irradiated graphite now requires a route for its safe immobilisation and disposal [2,3].…”