燃煤发电厂气态流出物辐射环境影响研究

Study on the Radiation Environmental Effect of Gaseous Effluents From Coal-Fired Power Plant

目前,燃煤发电厂对环境和公众产生的辐射影响引起了广泛关注。本文选择长江沿岸具有代表性的三家燃煤发电厂为研究对象,基于电厂气态流出物中主要放射性核素的年排放量,采用烟囱直接排放和沉降进入水体两种途径的评价方法,评估燃煤发电厂气态流出物对周围环境造成的辐射影响。结果表明:三家燃煤发电厂气态流出物排放造成80km范围内辐射影响很小,归一化最大个人年有效剂量分别为3.02×10^(-4)、4.32×10^(-5)、8.50×10^(-5 )Sv/GW;辐射剂量主要来自^(210)Po和^(210)Pb直接排放通过食入照射途径的贡献,远大于其进入水体及222Rn排放对剂量的贡献。由于210Pb具有相对较长的半衰期,导致其在土壤中的比活度增加;基于文中210Pb沉积浓度的分析,建议相关研究关注燃煤发电厂下风向30km范围内210Pb的长期辐射影响。本研究结果可为类似厂址的辐射影响评价提供技术支持,为内陆核电建设中公众沟通和技术研究工作提供基础数据,也为政府相关部门的决策提供参考。

In recent years,it has attracted wide attention that the radiation impact on the environment and the public from the coal-fired power plant.Three representative coal-fired power plants along the Yangtze River were selected as the research object,and the evaluation methods of direct emission and settlement into water body were adopted to evaluate the radiation effects of the gaseous effluents on the surrounding environment based on the annual emissions of the main radionuclides from coal-fired power plants.The results showed that the gaseous effluents from three coal-fired power plants caused very little radiation effect within the range of 80 km,and the maximum normalized individual dose were respectively 3.02×10-4,4.32×10-5 and 8.50×10-5 Sv/GW.The major contributor to dose was found to be the direct emission of 210 Po and 210 Pb,whose impact was far greater than that of their entry into the water and the contribution of 222 Rn.It was also found that the critical pathway was food ingestion.The relatively long half-life of 210 Pb resulted in its specific activity in the soil was increased,and it was suggested that the related research focus on its long-term radiation effect within the range of 30 km on the basis of analysis of 210 Pb deposition concentration.The results obtained can provide technical support for the radiation impact assessment of similar site,and can provide basic data for public communication and technical research in the construction of inland nuclear power,and also provide reference for decision-making of relevant government departments.