Contaminated runoff stormwater from urban environments carries several contaminants to water bodies, thereby affecting the health of living beings and ecological systems. Among all the contaminants, heavy metals possess high toxicity and impact water quality. The stormwater management through green infrastructures composed by adequate materials can provide an excellent solution, simultaneously ensuring the appropriate hydraulic performance and contaminant removal rate. The proposed research aims at the elimination of heavy metals (i.e. Ni, Cu, Zn, Cd and Pb) through column experiments by selecting four possible and novel treatments for urban stormwaters. Two lightweight aggregates (Arlita and Filtralite) were tested separately and in combination with CaCO₃. The study determines the efficiency and lifetime of each treatment by varying the interaction time between the filter materials and contaminated water and the type of filter. The observed removal mechanisms were closely related to the changes in pH due to the interactions between water and different materials. The reductions in heavy metal concentrations depend on the type of heavy metal, interaction time and type of filter material. Results indicate that the combined use of CaCO₃, Arlita and Filtralite did not improve the removal rates of heavy metals. However, it decreased the efficiency of the decontamination process. The significance of this study lies on the removal efficiency of Arlita and Filtralite as decontamination treatments. Both the tested lightweight aggregates led to a considerable decrease in the heavy metal concentrations in urban runoff stormwater although Filtralite was particularly efficient. After 4 weeks, the treatments were still successfully reducing and stabilising 99% of the heavy metals in the contaminated stormwater. These results confirm that the lifetime of the tested lightweight aggregates is adequate and emphasise, as a novel application of these materials, on their feasibility for the improvement of urban stormwater quality.

来自城市环境的受污染的径流雨水将几种污染物带入水体，从而影响了生物和生态系统的健康。在所有污染物中，重金属具有高毒性并影响水质。在通过适当的材料组成的绿色基础设施雨水管理可以提供优良的解决方案，同时确保适当的液压性能和污染物去除速率。拟议的研究旨在通过选择四种可能且新颖的城市雨水处理方法，通过柱实验消除重金属（例如，Ni，Cu，Zn，Cd和Pb）。分别对两种轻质骨料（Arlita和Filtralite）进行了测试，并与CaCO ₃结合使用。该研究通过改变过滤材料与污水和过滤器类型之间的相互作用时间来确定每种处理的效率和寿命。由于水和不同物质之间的相互作用，观察到的去除机理与pH的变化密切相关。重金属浓度的降低取决于重金属的类型，相互作用时间和过滤材料的类型。结果表明，CaCO ₃的联合使用，Arlita和Filtralite不能提高重金属的去除率。但是，它降低了净化过程的效率。这项研究的意义在于将Arlita和Filtralite作为去污处理剂的去除效率。尽管Filtralite效率特别高，但两种经过测试的轻质骨料均导致城市径流雨水中的重金属浓度显着降低。4周后，这些处理仍能成功减少并稳定受污染雨水中99％的重金属。这些结果证实了被测试的轻质骨料的寿命是足够的，并且作为这些材料的一种新颖应用，强调了它们改善城市雨水质量的可行性。