特定堆型的一回路冷却剂中通过加入氨调控pH,并利用其辐解产物抑制氧化性物质的浓度,从而维持冷却剂的还原性状态。在此过程中,氨浓度与pH调控产生显著的联动影响,需要建立可模拟不同控制策略下水化学行为的模型,实现pH和溶解氢浓度控...特定堆型的一回路冷却剂中通过加入氨调控pH,并利用其辐解产物抑制氧化性物质的浓度,从而维持冷却剂的还原性状态。在此过程中,氨浓度与pH调控产生显著的联动影响,需要建立可模拟不同控制策略下水化学行为的模型,实现pH和溶解氢浓度控制。本工作基于RETA反应堆系统分析程序,开发了一个适用于压水堆型冷却剂辐解产物输运的模型,模型预测NH_(3)和H_(2)浓度与实验结果的均方误差分别为1.79×10^(−8)和5.69×10^(−8)。以KLT-40S堆型为对象,构建并对比分析了三种加氨调控策略:初始弥散加氨、源恒速加氨及基于除氢优化的源恒速加氨。在模拟过程中,设置了冷却剂初始参数与辐射场条件,逐步调整加氨速率与除氢时机。每种策略均模拟至系统达到准稳态(1.6×10^(4) s),以评估其对pH和溶解氢浓度的调控效果。结果显示,初始氨弥散策略简单直接,可维持体系的还原性但对冷却剂pH调控的时间小于5 h;源恒速加氨可长时间有效调节冷却剂pH,但会带来溶解氢浓度过高的问题,需匹配相应的除氢方案。采用基于除氢优化的源恒速加氨策略,能够同时满足稳定控制pH和溶解氢浓度的要求,加氨速率为1.64 g·s^(−1),加氨开始1200 s后开启除氢装置,除氢速率0.014 g·s^(−1),化学状态稳定后冷却剂的pH为6.9,溶解氢浓度为30~35 mL·kg−(1)(Standard Temperature and Pressure,STP)。本工作有望为新堆型研发和水化学控制策略的优化提供参考。展开更多
IEA-R1 nuclear reactor operation has the routine to control uranium content in pool water to be in trace range below 50 μg/L. There are several routes to determine the uranium trace content in water in the lite...IEA-R1 nuclear reactor operation has the routine to control uranium content in pool water to be in trace range below 50 μg/L. There are several routes to determine the uranium trace content in water in the literature;voltammetry has been systematically employed. In the present study, the chosen chemical determination of uranium traces used the voltammetric method known as AdCSV (adsorptive cathodic stripping voltammetry). This technique, based on mercury voltammetry, is an adequate methodology to determine uranium traces. The chloranilic acid [CAA] (2,5-dichloro-3,6-dihydroxy-1,4-benzo-quinone) is indicated as chelating agent. The redox reaction of UO2+2?with CAA is sensitive in the range of 2 2(CAA)2] reduction potential. In this work, we present the uranium trace results for IEA-R1 reactor water, sampled after an operation routine shutdown. The uranium trace determination for IEA-R1 pool water showed content around 1 μg/L [U] with statistical significance. Therefore the IEA-R1-reactor-water purification showed to be adequate and safe.展开更多
The purpose of the study is to analyze the breeding ratio of a supercritical water cooled fast reactor (SCFR) and to increase the breeding core of SCFR. The sensitivities of assembly parameters, core arrangements and ...The purpose of the study is to analyze the breeding ratio of a supercritical water cooled fast reactor (SCFR) and to increase the breeding core of SCFR. The sensitivities of assembly parameters, core arrangements and fuel nuclide components to the breeding ratio are analyzed. In assembly parameters, the seed fuel rod diameter has higher sensitivities to the conversion ratio (CR) than the coolant tube diameter in blanket. Increasing heavy metal fraction is good to CR improvement. The CR of SCFR also increases with a reasonable core arrangement and Pu isotope mass fraction reduction in fuel, which can achieve more negative coolant void reactivity coefficient at the same time. The breeding ratio of SCFR is 1.03128 with a new core arrangement. And the coolant void reactivity coefficient is negative, which achieves a fuel breeding in initial fuel cycle.展开更多
文摘特定堆型的一回路冷却剂中通过加入氨调控pH,并利用其辐解产物抑制氧化性物质的浓度,从而维持冷却剂的还原性状态。在此过程中,氨浓度与pH调控产生显著的联动影响,需要建立可模拟不同控制策略下水化学行为的模型,实现pH和溶解氢浓度控制。本工作基于RETA反应堆系统分析程序,开发了一个适用于压水堆型冷却剂辐解产物输运的模型,模型预测NH_(3)和H_(2)浓度与实验结果的均方误差分别为1.79×10^(−8)和5.69×10^(−8)。以KLT-40S堆型为对象,构建并对比分析了三种加氨调控策略:初始弥散加氨、源恒速加氨及基于除氢优化的源恒速加氨。在模拟过程中,设置了冷却剂初始参数与辐射场条件,逐步调整加氨速率与除氢时机。每种策略均模拟至系统达到准稳态(1.6×10^(4) s),以评估其对pH和溶解氢浓度的调控效果。结果显示,初始氨弥散策略简单直接,可维持体系的还原性但对冷却剂pH调控的时间小于5 h;源恒速加氨可长时间有效调节冷却剂pH,但会带来溶解氢浓度过高的问题,需匹配相应的除氢方案。采用基于除氢优化的源恒速加氨策略,能够同时满足稳定控制pH和溶解氢浓度的要求,加氨速率为1.64 g·s^(−1),加氨开始1200 s后开启除氢装置,除氢速率0.014 g·s^(−1),化学状态稳定后冷却剂的pH为6.9,溶解氢浓度为30~35 mL·kg−(1)(Standard Temperature and Pressure,STP)。本工作有望为新堆型研发和水化学控制策略的优化提供参考。
文摘IEA-R1 nuclear reactor operation has the routine to control uranium content in pool water to be in trace range below 50 μg/L. There are several routes to determine the uranium trace content in water in the literature;voltammetry has been systematically employed. In the present study, the chosen chemical determination of uranium traces used the voltammetric method known as AdCSV (adsorptive cathodic stripping voltammetry). This technique, based on mercury voltammetry, is an adequate methodology to determine uranium traces. The chloranilic acid [CAA] (2,5-dichloro-3,6-dihydroxy-1,4-benzo-quinone) is indicated as chelating agent. The redox reaction of UO2+2?with CAA is sensitive in the range of 2 2(CAA)2] reduction potential. In this work, we present the uranium trace results for IEA-R1 reactor water, sampled after an operation routine shutdown. The uranium trace determination for IEA-R1 pool water showed content around 1 μg/L [U] with statistical significance. Therefore the IEA-R1-reactor-water purification showed to be adequate and safe.
文摘The purpose of the study is to analyze the breeding ratio of a supercritical water cooled fast reactor (SCFR) and to increase the breeding core of SCFR. The sensitivities of assembly parameters, core arrangements and fuel nuclide components to the breeding ratio are analyzed. In assembly parameters, the seed fuel rod diameter has higher sensitivities to the conversion ratio (CR) than the coolant tube diameter in blanket. Increasing heavy metal fraction is good to CR improvement. The CR of SCFR also increases with a reasonable core arrangement and Pu isotope mass fraction reduction in fuel, which can achieve more negative coolant void reactivity coefficient at the same time. The breeding ratio of SCFR is 1.03128 with a new core arrangement. And the coolant void reactivity coefficient is negative, which achieves a fuel breeding in initial fuel cycle.
