Université de Limoges, PEREINE EA 7500 GRESE URA IRSTEA, 123 avenue Albert Thomas, 87060, Limoges, France.
Université de Limoges, IRCER UMR CNRS 7315, 12 rue de l'Atlantis, 87068, Limoges, France.
Environ Sci Pollut Res Int. 2019 May;26(14):14473-14482. doi: 10.1007/s11356-019-04737-7. Epub 2019 Mar 14.
The aims of this study correspond to (i) determine the feasibility of synthesize geomaterial from two main Pb-contaminated mining sediments (Sed1 and Sed2) without prior activation in substitution to metakaolin (MK), (ii) understand the mechanisms involved toward two types of silicate solution (Na and K one), and (iii) to evaluate the change in the Pb metallic element speciation and leaching after alkali treatment. The raw material as well as consolidated material were characterized by X-ray diffraction, infrared spectroscopy, and electron microscopy. The mechanical properties were evaluated, and the leaching behavior realized according to EN12457-2. The results evidence the limit of mining sediment incorporation by substitution near 50% whatever the sediments and the alkaline solution used. There is no difference in the mechanical properties up to 10% substitution then decrease with the increase of sediment content. The Pb-bearing phases are dissolved during alkaline treatment and redistributed in the geomaterial matrix. Finally, the leaching experiments clearly evidenced the possibility to stabilize Pb into MK-based geomaterial matrix up to 25-30% weight of mine waste.
（i）确定在不预先激活的情况下，用两种主要的含 Pb 污染的矿渣（Sed1 和 Sed2）来合成地质材料的可行性，以替代偏高岭土（MK）；（ii）理解两种类型的硅酸盐溶液（Na 和 K 溶液）的参与机制；（iii）评估碱处理后 Pb 金属元素形态和浸出的变化。原材料和固结材料都通过 X 射线衍射、红外光谱和电子显微镜进行了表征。力学性能也进行了评估，并根据 EN12457-2 进行了浸出实验。结果表明，无论使用哪种矿渣和碱性溶液，其替代率接近 50%时，矿渣的掺入量都达到了极限。在替代率为 10%之前，力学性能没有差异，随后随着矿渣含量的增加而下降。在碱性处理过程中，含 Pb 相被溶解并重新分布在地质材料基质中。最后，浸出实验清楚地表明，将 Pb 稳定在基于 MK 的地质材料基质中，其含量可达 25-30%的矿渣重量。
