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Norway’s Halden reactor takes first step toward decommissioning
The government of Norway has granted the transfer of the Halden research reactor from the Institute for Energy Technology (IFE) to the state agency Norwegian Nuclear Decommissioning (NND). The 25-MWt Halden boiling water reactor operated from 1958 to 2018 and was used in the research of nuclear fuel, reactor internals, plant procedures and monitoring, and human factors.
P. Mohanakrishnan, H. C. Huria
Nuclear Science and Engineering | Volume 68 | Number 2 | November 1978 | Pages 220-226
Technical Note | doi.org/10.13182/NSE78-A27294
Articles are hosted by Taylor and Francis Online.
A theoretical analysis of the reactivities of experimentally measured uniform light-water-moderated and -reflected PuO2 in UO2 lattices and Pu(NO3)4 solutions is presented here. The mixed-oxide single-rod lattices are homogenized by the use of multigroup integral transport theory, and diffusion theory is used for the cylindrical core calculations. The cross sections are derived from the WIMS library. The homogeneous spherical Pu(NO3)4 solutions are analyzed by discrete-ordinates transport theory. Due to the small size of these assemblies, it is necessary that one-dimensional core calculations also be performed with a cross-section energy-group structure that can accurately represent neutron slowing down and thermalization at the core-reflector interface. Due to the uncertainty present in the Battelle Northwest Laboratories analyses of the mixed-oxide lattices, the agreement of our predictions for these lattices with measurement is considered to be more satisfactory. Our reactivity predictions agree generally within +0.6% of measurements for the mixed-oxide lattices and within 1% for the solution systems.
