调查使用废物设计的青路面表面下水的污染水平
Lee P Leon1, Monique Aldana1, Vinai Lutchman1
1Department of Civil and Environmental Engineering, University of the West Indies, St Augustine, Port of Spain, Trinidad and Tobago.
概括
青路面中的回收材料,如碎 (CRM) 和回收混凝土聚合物 (RCA),可以出污染物,特别是化物和颜色. 需要进一步的研究来平衡可持续性与水质保护.
科学领域:
- 环境工程 环境工程
- 材料科学 材料科学 材料科学
- 可持续的路面设计
背景情况:
- 将废物材料如碎 (CRM),回收青路面 (RAP),回收混凝土聚合物 (RCA) 和被油污染的沙子 (OCS) 整合到青中,提供了可持续性的好处.
- 然而,这些材料可能会通过地表径流和透造成水污染的风险.
研究的目的:
- 评估含有各种回收材料的青混合物的短期漏特性.
- 为了比较这些可持续青选项与传统热混合青 (HMA) 的环境影响.
主要方法:
- 带有CRM,RAP,RCA和OCS的圆柱形青样本被浸入水中30分钟至24小时.
- 液分析了度,颜色,pH值,导电性,酸盐,酸盐和化物.
- 进行了统计分析 (Welch's ANOVA,Kruskal-Wallis) 和风险系数 (RQ) 分析.
主要成果:
- 与回收混凝土聚合物 (RCA) 和污染油砂 (OCS) 的青混合物显示出污染物排放量最高的污染物.
- 化物和颜色是漏最敏感的指标.
- 虽然直接的生态风险很低 (RQ<1),但化物水平的显著变化被观察到,颜色显示出近乎显著的趋势.
结论:
- 在青路面上使用回收材料对水质产生了环境权衡.
- 缓解策略,如预处理,优化材料比率和扩展现场验证至关重要.
- 将路面可持续性与水资源保护相平衡,需要仔细考虑和进一步研究,特别是在潮干周期的热带气候中.
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