摘要
以某地区8个煤矿和13个燃煤电厂为研究对象,通过室外取样与室内检测,对粉煤灰生产利用中放射性核素^(238)U、^(232)Th、^(226)Ra、^(40)K进行比活度分析和评价。结果表明,在原煤到粉煤灰过程中,4种放射性核素(^(238)U、^(232)Th、^(226)Ra、^(40)K)的富集系数在2.15~3.79,富集系数与燃煤浓缩比基本一致,确定转移系数为3.79;在粉煤灰到粉煤灰砖中,4种放射性核素(^(238)U、^(232)Th、^(226)Ra、^(40)K)的富集系数为0.65~1.04,富集系数与粉煤灰掺比基本相同,确定转移系数为0.70。整个过程放射性核素未发生损失,且不因放射性水平高低影响其转移系数。粉煤灰砖放射性水平评价表明,该地区8类粉煤灰砖符合国家标准要求,适用于任何途径(除X-8外均可作为建筑主体);剩余5类粉煤灰砖仅可用于建筑物的外饰面等与人体接触不密切的建筑上,后续仍需加强该类粉煤灰砖在生产、使用等方面的监督。该地区13类粉煤灰砖的γ辐射吸收剂量率水平较高,但其中6类粉煤灰砖的年有效剂量率低于全国推荐值,表明对人体的辐射危害较小,可以用于建筑材料使用。
Taking 8 coal mines and 13 coal-fired power plants in a certain area as research objects,specific activities of four radionuclides(^(238)U,^(232)Th,^(226)Ra and ^(40)K)in coal-fly ash chain were analyzed and evaluated by outdoor sampling and indoor detection.The results show that enrichment coefficients of four radionuclides in raw coal-fly ash are 2.15—3.79,which is basically consistent with concentration ratio of coal,and transfer coefficient is determined as 3.79.In fly ash-fly ash brick,enrichment coefficients of four radionuclides range from 0.65 to 1.04,which is basically the same as fly ash ratio,and transfer coefficient is determined as 0.70.No loss of radionuclides occurs during the whole process,and transfer coefficient is not affected by level of radioactivity.Radioactive level evaluation of fly ash bricks shows that eight types of fly ash bricks in this area meet the requirements of national standards and are suitable for any way(can be used as the main building except X-8).The remaining five types of fly ash bricks can only be used in buildings with no close contact with human bodies,such as exterior finishes of buildings.Supervision on production and use of such fly ash bricks should be strengthened in the follow-up.Among the 13 types of fly ash bricks in this area,the annual effective dose rate of 6 types of fly ash bricks is lower than the national recommended value,indicating that the radiation harm to human body is small,and can be used as building materials.
作者
李冠超
杨波
孙功明
高柏
方正
丁燕
LI Guan-chao;YANG Bo;SUN Gong-ming;GAO Bai;FANG Zheng;DING Yan(Radiation Environment Monitoring Center of Guangdong Province Nuclear Industry Geological Bureau,Guangzhou 510800,China;State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,China)
出处
《有色金属（冶炼部分）》
CAS
北大核心
2022年第11期89-96,共8页
Nonferrous Metals（Extractive Metallurgy)
基金
广东省生态环境厅项目(115-2019-XMZC-0009-30-0020)。
