Nuclear Techniques ›› 2015, Vol. 38 ›› Issue (1): 10601-010601.doi: 10.11889/j.0253-3219.2015.hjs.38.010601

• NUCLEAR ENERGY SCIENCE AND ENGINEERING • Previous Articles     Next Articles

Optimal design of burnable poisons for the advanced plate-type high-temperature reactor

WEI Shuhua1,2,3 YU Xiaohan1,3 ZOU Yang1,3 DAI Ye1,3 ZHU Guifeng1,2,3   

  1. 1(Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Jiading Campus, Shanghai 201800, China) 2(University of Chinese Academy of Sciences, Beijing 100049, China) 3(Key Laboratory of Nuclear Radiation and Nuclear Energy Technology, Chinese Academy of Sciences, Shanghai 201800, China)
  • Received:2014-09-22 Revised:2014-10-16 Online:2015-01-10 Published:2015-01-07

Abstract: Background: The advanced high-temperature reactor (AHTR) is conceptional designed by Oka Ridge National Laboratory (ORNL) for a central generating station type of 3400 MWt fluoride-salt-cooled high-temperature reactor (FHR). The design employs an innovative plate-type coated particle fuel assembly with uranium enrichment of 9%?20%. The initial core excess reactivity is too large to be handled by the control blades alone. Purpose: This study aims to eliminate the problem of high excess reactivity by analyzing the use of spherical burnable particles. Methods: First of all, according to the physical properties and burn-up chain of burnable poison (BP) materials, six potential candidates were analyzed, and four of them, i.e. B4C, Gd2O3, CdO and Er2O3 were chosen for further study. Then, the MCNP and Origen2 coupling program were employed to optimize the BP loading using single fuel assembly calculations. Finally, the keff, which changes with burn-up time, was used as optimization parameter to attain the optimal radius and mass. Results: Simulation results showed that the reactivity swing reduced from 39% to about 4.4%, 6.8%, 7.3% and 13.1% respectively, when loading 176 g Er2O3 with a radius of 740 μm, 3 g B4C with a radius of 100 μm, 120 g Gd2O3 with a radius of 1 500 μm and 160 g CdO with a radius of 2 000 μm separately. Conclusion: Er2O3 is recommended as the best BP material to eliminate the problem of high excess reactivity in plate-fuel type AHTR.

Key words: Advanced high temperature reactor (AHTR), Plate-type fuel element, Burnable poison (BP)