使用有机合剂稳定城市固体废物焚烧飞灰中的重金属:风险评估和功能机制的洞察力
1School of Energy and Environmental Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083, China.
The Science of the total environment
|January 11, 2024
概括
稳定城市固体废物焚烧飞灰 (MSWI FA) 用dithiocarbamate (DTC) 结合剂 (CA) 减少重金属 (HM) 漏. 然而,在酸性/性条件下以及长期储存期间,环境风险仍然存在.
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:
- 稳定城市固体废物焚烧飞灰 (MSWI FA) 的垃圾填埋处理是一种主要的处置方法.
- 关于MSWI-FA-chelated产品在各种垃圾填埋环境中的稳定性研究有限.
- 评估重金属 (HM) 漏和稳定MSWI FA的环境风险对于安全处置至关重要.
研究的目的:
- 评估三种基于dithiocarbamate (DTC) 的合剂 (CA) 在稳定重金属 (HM) 的有效性.
- 在各种垃圾填埋场场景下,评估稳定MSWI FA产品的漏毒性和环境风险.
- 确定最佳的CA添加剂水平,以满足填埋标准,并了解长期稳定性.
主要方法:
- 三个基于DTC的CA (TS-300,SDD,PD) 用于稳定MSWI FA中的HM.
- 在混合和分隔的垃圾填埋场场景 (模拟酸雨) 下进行了泄漏毒性测试.
- 在不同的CA添加剂水平和pH条件下测量了HM漏度,使用28天的储存评估.
主要成果:
- 在混合情景中,低CA添加剂水平 (0.3%) 符合卫生垃圾填埋标准 (GB16889-2008).
- 需要更高的CA水平 (1.5%TS-300,6.0%SDD,8.0%PD) 才能在酸性漏场景中达到标准.
- 由于其结构,TS-300表现出优越的性能,但在TS-300和SDD储存28天后,显著的HM漏增加.
结论:
- 在特定条件下,基于DTC的CA可以有效地减少MSWI FA的HM漏,以满足填埋标准.
- 在极端pH环境和长期储存期间,必须考虑环境风险,特别是增加HM漏.
- 仔细选择CA类型和剂量,以及储存考虑,对于处理的MSWI FA的安全和稳定的处置至关重要.
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