来自中国代表性燃煤发电厂的磁铁纳米颗粒:除尘捕获及其最终大气排放
Zhiqiang Shi1, Miao Xu1, Lingyan Wu1
1Key Laboratory of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China.
The Science of the total environment
|September 1, 2024
概括
煤炭飞灰含有磁性纳米颗粒 (MNP),可能对健康造成风险. 静电织物沉器最好去除这些MNP,但逃逸的飞灰仍然会释放出大量有毒的纳米粒子.
科学领域:
- 环境科学 环境科学
- 纳米技术纳米技术
- 毒理学 毒理学 毒理学
背景情况:
- 关于煤炭燃烧来源的磁纳米颗粒 (MNP) 及其对健康的影响的数据有限.
- 了解燃煤发电厂 (CFPP) 的MNP排放对于风险评估至关重要.
研究的目的:
- 从中国的CFPP采用不同的除尘系统来量化煤炭飞灰 (CFAs) 中的MNP.
- 研究各种煤炭燃烧副产品中MNP的大小,度和纯度.
- 评估MNP的排放率和潜在的健康风险,特别是那些逃离堆的MNP.
主要方法:
- 使用单颗粒ICP-MS从CFA中提取和量化MNP.
- 分析不同CFPP阶段和除尘装置的MNP特征 (大小,度,Fe含量,有毒金属丰度).
- 从逃逸的飞灰中计算MNP排放率.
主要成果:
- 捕获的CFA中的MNP度随着除尘阶段的增加而增加,而大小则下降.
- 静电织物集成沉器显示出优越的MNP去除效率.
- 逃逸的飞灰 (EFA) 呈现出最高的MNP数度 (1.2 × 10^7颗粒/mg) 和最小的尺寸 (78 nm).
- 在MNP总排放量中,EFA贡献了3.56%,排放率为1.9 × 10^15颗粒/小时.
- 随着颗粒大小的减少,MNP纯度和有毒金属吸附度增加,EFA显示有毒金属比底层灰多3.3倍.
结论:
- 逃出飞灰中的微型MNP高度缩,并富含有毒金属,构成严重的吸入风险.
- 除尘装置在减轻MNP排放方面的有效性各不相同,其中静电织物集成沉器是最有效的.
- 这些纯粹的,有毒的金属吸附性MNP的大气排放存在协同毒性的风险.
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