The use of MOX caramel fuel mixed with 241Am, 242mAm and 243Am as burnable absorber actinides for the MTR research reactors

Abstract

The MOX (UO₂&PuO₂) caramel fuel mixed with ²⁴¹Am, ^242mAm and ²⁴³Am as burnable absorber actinides was proposed as a fuel of the MTR-22MW reactor. The MCNP4C code was used to simulate the MTR-22MW reactor and estimate the criticality and the neutronic parameters, and the power peaking factors before and after replacing its original fuel (U₃O₈-Al) by the MOX caramel fuel mixed with ²⁴¹Am, ^242mAm and ²⁴³Am actinides. The obtained results of the criticality, the neutronic parameters, and the power peaking factors for the MOX caramel fuel mixed with ²⁴¹Am, ^242mAm and ²⁴³Am actinides were compared with the same parameters of the U₃O₈-Al original fuel and a maximum difference is -6.18% was found. Additionally, by recycling 2.65% and 2.71% plutonium and ²⁴¹Am, ^242mAm and ²⁴³Am actinides in the MTR-22MW reactor, the level of ²³⁵U enrichment is reduced from 4.48% to 3% and 2.8%, respectively. This also results in the reduction of the ²³⁵U loading by 32.75% and 37.22% for the 2.65%, the 2.71% plutonium and ²⁴¹Am, ^242mAm and ²⁴³Am actinides, respectively.

Keywords: Criticality safety; MCNP4C code; MOX caramel fuel; MTR-22MW reactor; Neutronic parameters.