石膏和城市固体废物焚烧底灰混合物的化学性能,可作为道路基材的潜在用途
Shreya Mondhe1, Kate D Weiksnar1, Steven J Laux1
1Department of Environmental Engineering Sciences, University of Florida, P. O. Box 116450, Gainesville, FL, 32611-6450, USA.
Chemosphere
|May 8, 2025
概括
将酸性 (PG) 与性城市固体废物焚烧 (MSWI) 底灰 (BA) 混合,可以减少微量金属和化物出. 这种新的废物再利用策略为环境影响较小的建筑应用提供了切实可行的途径.
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:
- 全球越来越多的兴趣是重复使用废物材料,如石膏 (PG) 和城市固体废物焚烧 (MSWI) 底灰 (BA) 在建筑中.
- 对于PG和BA存在独立研究,但它们用于资源回收的联合使用是新的.
- 需要评估混合废物材料对环境的影响.
研究的目的:
- 评估来自三个来源的PG和BA混合物的微量金属和化物度.
- 为了评估这些混合材料的漏行为,用于建筑应用.
- 为了确定混合是否可以减轻与个别废物组件相关的环境风险.
主要方法:
- 三个MSWI底层灰 (BA) 的来源与石膏 (PG) 混合.
- 分析了微金属 (As,Pb,Cd,Sb,Cu) 和化物的总和可浸出度.
- 来自混合材料的化剂的pH值被测量并与成分度相关联.
主要成果:
- 与监管门相比,在单个BA和PG样本中发现了总As和Pb水平的升高.
- 将PG与BA混合导致更中性的化剂pH (5.5-10.6),随着PG含量增加而下降.
- 在BA-PG混合物中观察到可浸的As,Cd,Sb和化物的显著减少,其中一些混合物低于监管选限值.
结论:
- BA-PG混合物显示了建筑垃圾再利用的潜力,为资源回收和废物转移提供了途径.
- 通过混合实现的pH值修改在降低污染物如As,Cd,Sb和化物的流动性方面发挥着至关重要的作用.
- 适当的混合设计和对现场条件的考虑对于成功实施和最大限度地减少环境风险至关重要.
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