随着核电厂中对正常满功率运行时裂变产物和腐蚀产物控制水平的不断提高,主要的弱β释放体(如氚和C-14)对公众的辐射影响变得日益重要。GB 6249-2011中对流出物中氚和C-14的单机组和厂址排放总量规定了控制值,也对内陆厂址排放口下游1 km处受纳水体中氚浓度进行了限制。本文根据核电厂中氚和C-14的主要产生途径,采用理论方法对其产生量进行分析,并从其产生途径和设计的角度,提出了切实可行的对释放到环境中的氚和C-14进行控制的方法和措施,以用于优化电厂设计,为环境影响评价和安全分析提供审评的依据。 As the control technology of fission and corrosion products develops during the full power operation in the nuclear power plant, the impact from the main β emitters (like tritium and Carbon-14) to people becomes increasingly important. Certain limits of the tritium and carbon-14 concentration in the effluences for both single unit and site are established in GB6249-2011, also, it includes the tritium concentration restriction in the 1 km downstream water from the discharge canal for inland sites. Based on the main generation pathway, a theoretical method is applied to analyze the tritium and carbon-14 generations in this paper, and some tritium and carbon-14 release control recommended measures are provided from both the generating pathway and design aspects. Also, these measures could be used for the NPP design optimization, safety analysis and environment assessment.
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