The fluoride salt-cooled high-temperature reactor(FHR) uses molten FLi Be salt as the coolant, which introduces a corrosive effect on the alloy-N structure material. Fission neutrons activate the corroded alloy-N,alon...The fluoride salt-cooled high-temperature reactor(FHR) uses molten FLi Be salt as the coolant, which introduces a corrosive effect on the alloy-N structure material. Fission neutrons activate the corroded alloy-N,along with alloy-N structures inside the reactor vessel. The activation products of the alloy-N have a big impact on radiation protection during operation, maintenance, and decommissioning of the reactor. We have constructed a SCALE 6.1 model for the core of a typical 10 MW th FHR and analyzed the activity of each constituent of the irradiated alloy-N. The results show that the activity is predominantly due to short-lived^(28) Al,^(60m) Co,^(56) Mn,^(51)Ti, and ^(52) V, as well as long-lived ^(60) Co,^(51)Cr,^(55)Fe,^(59)Fe, and ^(54) Mn.Furthermore, because of their relatively long half-life and high-energy c-rays emissions,^(60) Co and ^(54)Mn are the major contributors to the radiation source terms introduced by alloy-N activation. The yield of ^(60)Co and ^(54)Mn per unit mass of alloy-N under the current core design is 5.58*10~5 and 1.55 * 10~3 Bq MWd^(-1)g^(-1), respectively.The results of this paper, combined with future corrosion studies, may provide a basis for evaluating long-term radiation source terms of the primary loop salt and components.展开更多
基金Supported by the ‘‘Strategic Priority Research Program’’ of the Chinese Academy of Sciences(Grant No.XDA02050100)
文摘The fluoride salt-cooled high-temperature reactor(FHR) uses molten FLi Be salt as the coolant, which introduces a corrosive effect on the alloy-N structure material. Fission neutrons activate the corroded alloy-N,along with alloy-N structures inside the reactor vessel. The activation products of the alloy-N have a big impact on radiation protection during operation, maintenance, and decommissioning of the reactor. We have constructed a SCALE 6.1 model for the core of a typical 10 MW th FHR and analyzed the activity of each constituent of the irradiated alloy-N. The results show that the activity is predominantly due to short-lived^(28) Al,^(60m) Co,^(56) Mn,^(51)Ti, and ^(52) V, as well as long-lived ^(60) Co,^(51)Cr,^(55)Fe,^(59)Fe, and ^(54) Mn.Furthermore, because of their relatively long half-life and high-energy c-rays emissions,^(60) Co and ^(54)Mn are the major contributors to the radiation source terms introduced by alloy-N activation. The yield of ^(60)Co and ^(54)Mn per unit mass of alloy-N under the current core design is 5.58*10~5 and 1.55 * 10~3 Bq MWd^(-1)g^(-1), respectively.The results of this paper, combined with future corrosion studies, may provide a basis for evaluating long-term radiation source terms of the primary loop salt and components.
