抑制机制有助于从焚烧底灰中的低泄率
Yasumasa Tojo1, Mikako Ishii1, Kazuki Tamura1
1Graduate School of Engineering, Hokkaido University, N13W8 Kitaku, Sapporo, 0608628, Japan.
Journal of environmental radioactivity
|November 20, 2024
概括
从底层灰中出放射性的数量很低,这是因为它被缩在类似微的颗粒中. 这些颗粒含有,和,形成一种玻璃状物质,使固定不动,减少垃圾填埋场对环境的释放.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
背景情况:
- 福岛第一核事故产生了被放射污染的城市固体废物 (MSW).
- 燃烧MSW导致放射性留在飞和底层灰中.
- 底层灰 (<8000 Bq kg-1 湿) 被填埋,但放射性的出机制尚不清楚.
研究的目的:
- 调查由底层灰从底层灰中出低放射的机制.
- 为了了解底层灰颗粒中的的行为.
主要方法:
- 在模拟带有稳定的底灰上进行了漏试验和显微观测.
- 进行了pH依赖测试,以评估泄漏.
- 使用了先进的分析技术,包括电子探针微分析,扫描电子显微镜,能量分散式X射线光谱和拉曼显微镜.
- 用微克林和碳酸进行模拟的联合加热实验.
主要成果:
- 随着pH值的下降,从底层灰中出的数量增加.
- 在中性pH范围内,有2-4%的被洗.
- 显微镜分析揭示了由,,和氧组成的聚颗粒,被确定为microcline.
- 联合加热实验表明,在微型表面上的玻璃状物质内固定,模仿底层灰颗粒.
结论:
- 集中在底层灰中的微基颗粒中.
- 一种玻璃状物质在微克林表面形成,封装并显著降低其透性.
- 这种封装机制解释了在垃圾填埋场沉积的底层灰中观察到的低放射泄露.
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