重金属在MSW垃圾填埋场共处置的超性飞灰中的释放动态,风险演变和驱动机制
Zhaozhi Jia1, Ya Xu2, Rongbin Xu3
1Chinese Research Academy of Environmental Sciences, Beijing, 100012, China; Shandong Technology and Business University, Yantai, Shandong, 264005, China.
Environmental pollution (Barking, Essex : 1987)
|June 27, 2024
概括
碳化控制了焚烧炉飞灰中的重金属释放,但Zn和Pb的度可以随着时间的推移而激增. 填埋这些灰会造成地下水污染的严重风险,特别是在沿海地区.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 废物管理 废物管理
背景情况:
- 焚烧炉飞灰是一个日益严重的全球废物问题.
- 垃圾填埋是一种常见的处理方法,但超性飞灰的行为需要进一步调查.
- 了解重金属释放和长期风险对于环境安全至关重要.
研究的目的:
- 为了研究超性飞灰中的重金属释放模式.
- 评估由于飞填埋而导致地下水中重金属污染的长期风险.
- 确定控制重金属释放的主要机制.
主要方法:
- 在室内进行模拟实验,以模拟垃圾填埋场的条件.
- 使用过程模拟建模来分析长期风险.
- 分析的重点是重金属度及其释放动态.
主要成果:
- 碳化被确定为控制重金属释放率的关键机制.
- 最初的释放速度很慢,但随着时间的推移,Zn和Pb度可能会显著增加.
- 据估计,Zn,Cd和Pb的地下水污染风险分别超过标准的39.50,6.70和5.99倍.
- 炉类型显著影响背景重金属度,格炉比流化床具有更高的风险.
- 由于降雨,沿海地区面临的风险更高,是内陆地区的5倍.
结论:
- 碳化对于管理飞灰至关重要,但存在增加重金属释放的潜力.
- 垃圾填埋的超性飞灰具有相当大的长期地下水污染风险,特别是Zn,Cd和Pb.
- 炉型和区域降雨模式是影响环境风险的关键因素.
- 监测和管理策略对于在MSWL (市政固体废物填埋场) 附近的沿海地区的浅地下水安全至关重要.
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