深燃耗球床式气冷快堆研究

Study on the deep burn-up fuel cycle of the pebble-bed gas-cooled fast reactor

气冷快堆是未来发展的第四代先进核能系统候选堆型之一,它可以满足核能的可持续性、安全可靠性和经济性要求。从反应堆物理和热工水力学的角度出发,设计了热功率300 MW的球床式气冷快堆,选择了碳化物燃料作为气冷快堆的燃料。用耦合燃耗计算程序COUPLE2.0模拟得到了深燃耗气冷快堆的铀燃料循环的平衡态。平衡态研究结果表明基于深燃耗的300 MW球床式气冷快堆可以提高铀资源的利用率同时降低乏燃料中的次锕系核素的含量。当燃料球直径为6 cm,燃料区的直径为5.5 cm,燃料占燃料区的体积的70%,燃料形式为UC,其中235U的初始富集度为12%时,燃料球通过堆芯的时间可以达到12 600 d,重金属燃耗深度为164.38 GWd/t,总的铀资源的利用率可以达到为28.03%。

Gas cooled fast reactor （GFR） is one type of the Generation Ⅳ nuclear system under evaluation for future deployment, which satisfies the Gen-Ⅳ goals in the area of sustainability, safety and economy. The concept design of the fuel and the core of the pebble bed GFR with 300 MWt were completed from the physical and thermal-hydraulic point and carbide fuel was chosed as the GFR＇s fuel in this paper. The coupled depletion calculation code COUPLE2.0 was used to get the equilibrium states of 300 MWt pebble bed GFR. The results showed that the 300 MWt pebble bed GFR based on the deep burn-up concept could effectively raise the availability of the uranium resources and decrease the pile-up of minor actinide. The availabiling of uranium resources would be up to 28.03%, the burn-up for heavy metal would be about 164.38 MWd/t and the fuel pebble once-through the core could up to about 12 600 days if the diameter of the fuel pebble is 6cm and the fuel zone is 5. 5 cm, the 70% volume of the fuel zone is filled with carbide fuel UC with the initial 235U enrichment of 12%.