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在从黑色沙子机械分离后,对不同级别的莫纳石进行放射性评估
N A Kotb1, M S Abd El Ghany2, Ashraf A El-Sayed3
1Radiation Protection Department, Hot Labs Center, Egyptian Atomic Energy Authority, Cairo, Egypt. n_kotb87@yahoo.com.
Scientific reports
|September 16, 2023
概括
埃及的黑沙含有莫纳,这是一个富含和的矿物质. 放射学评估显示,辐射暴露水平超过安全限值,需要为工人采取辐射安全措施.
科学领域:
- 地质化学和矿物学
- 辐射科学 辐射科学
- 环境健康 环境健康
背景情况:
- 在埃及黑沙中发现的莫纳是含有,和稀土元素的宝贵矿物.
- 鉴于采矿活动,评估来自原始放射性核酸的马射线暴露至关重要.
- 这项研究涉及莫纳矿开采和加工的放射性影响.
研究的目的:
- 为了对不同等级的莫纳石原料进行放射性评估.
- 为了量化关键放射性核酸的活性度 (232Th,238U,40K,138La).
- 计算相关的危险指数并评估对工人的潜在风险.
主要方法:
- 使用超纯探测器 (HPGe) 进行精确的活动测量.
- 分析了不同等级 (90%,75%,50%) 的莫纳样本.
- 计算吸收和有效剂量,以及危险参数.
主要成果:
- 对232Th,238U和40K的活性度被确定为每个莫纳酸盐等级.
- 90%莫纳的特定活动: 348,008±1406 Bq/kg (232Th), 69,299±2086 Bq/kg (238U), 27,510±245 Bq/kg (40K) 其他.
- 计算的有效和吸收剂量超过了工人的豁免限值 (20mSv/y),危险参数超过了推限值.
结论:
- 埃及黑沙中的莫纳石原料显示出大量的原始放射性核酸.
- 与莫纳石处理和加工相关的放射性风险是相当大的.
- 实施严格的辐射安全协议对于保护工人免受电离辐射危害至关重要.
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