Abstract：
In the construction industry, environmental behavior of aggregates has been monitored thanks to leaching tests, especially for alternative aggregates obtained from waste (e.g., construction and demolition waste, MSWI). Few studies were carried on the leaching behavior of natural aggregates, which are often not regulated for their substance release in most EU member states (as France). Leachable content of some heavy metals, halides, and sulfates on natural aggregates was investigated using up-flow percolation test EN 16637-3 and compared to threshold values. Only three samples (NS2, NG1, and NG8) show one element which exceeded threshold values (As, Zn, As, respectively), among the 19 natural aggregates tested for leaching. In this study, three natural aggregates (NG1, NS1, NS2) have been chosen because of their measurable leaching values. Total content was obtained through acid digestion. Influence of grain size on leaching results was investigated. Predominant release mechanisms were determined using EN 16637-3 - Annex D, based on percolation results such as pH, electrical conductivity, and leached content, and were then discussed. Detailed results for releases of As, Ba, Ni, Zn, SO42-, and F- were investigated. EN 16637-3 - Annex D shows some limits, especially for trace elements. The pH was found to be one of the most important factors influencing leaching release of most elements, being more important than grain size. By comparing total content with released quantities, it has been shown that As and Mo in NS2 are easily leached, hence present in a very soluble chemical form. Determining release mechanisms accurately in this study seems only possible for elements present in significant amounts.
摘要：
在建筑行业,通过浸出试验，已经监测了骨料的环境行为，特别是对于从废物中获得的替代骨料(例如，建筑和拆除废物，MSWI)。很少对天然骨料的浸出行为进行研究，在大多数欧盟成员国(如法国)，它们的物质释放通常不受监管。一些重金属的可浸出含量，卤化物,使用上流渗滤测试EN16637-3研究了天然骨料上的硫酸盐，并与阈值进行了比较。只有三个样本（NS2，NG1和NG8）显示一个元素超过了阈值（As，Zn,As,分别)，在19个天然骨料中进行了浸出测试。在这项研究中,由于其可测量的浸出值，因此选择了三种天然骨料（NG1，NS1，NS2）。通过酸消化获得总含量。研究了粒度对浸出结果的影响。主要释放机制使用EN16637-3-附录D确定，基于渗透结果，如pH，电导率，和浸出的内容，然后讨论。As版本的详细结果，Ba,Ni,Zn,SO42-,和F-被调查。EN16637-3-附录D显示了一些限制，特别是微量元素。发现pH是影响大多数元素浸出释放的最重要因素之一。比晶粒尺寸更重要。通过比较总含量和释放量，研究表明，NS2中的As和Mo容易浸出，因此以非常可溶的化学形式存在。在这项研究中准确确定释放机制似乎只有大量存在的元素才有可能。
