透水铺装改性基层对典型径流污染物动态除污实验研究

为提高透水铺装对雨水径流的净化作用,通过优选骨料和掺入添加剂的方法对透水铺装基层进行改性,制备了沸石基层、陶粒基层、掺粉煤灰砾石基层和掺膨润土砾石基层;同时制备一组传统砾石基层作为参照对比基层;并将改性后的基层和参照基层对雨水径流典型污染物COD、TP、TN、Cu~(2+)的削减作用进行了过滤吸附实验。实验结果表明,4种改性基层对污染物去除能力整体上较传统砾石基层均有一定程度的提高;但不同改性方法对污染物的去除效果差异较大。整体来看,掺膨润土砾石基层对污染物COD、TP、Cu~(2+)的去除效果最好;但在去除TN的实验中,除沸石基层外,其他基层对TN的去除效果皆不理想。研究结果表明,过滤除污实验中,掺入添加剂方面改性,掺膨润改性基层对于污染物削减效果最好;而掺入骨料方面,沸石改性基层去除效果最佳。建议将沸石作为骨料,膨润土作为添加剂制成改性基层,以最大化实现去除污染物的作用。

The adsorption experiments of Modified Permeable Pavement Base Layer

In order to improve the purification of rainwater runoff by permeable pavement, the base layer of permeable pavement is modified by mixing additives and optimal screening aggregates. Zeolite, ceramic, fly ash gravel and bentonite gravel base layers were prepared and a set of cement gravel base layer as reference. Reduction effect of modified base layers for pollutants, such as COD, TP, TN and heavy metal was studied. The results show that pollutants removal capability of 4 kinds of modified base layers are better than traditional gravel base layer, bentonite gravel base layer has the best performance in removing COD, TP and Cu2+. In the experiment of TN removal, except for the zeolite base layer, all the other modified base layers show an unsatisfactory removal capability. The results of the study show that in the aspect of modification by adding adsorbents, the bentonite can result in a better pollutant removal performance, while in the aspect of optimal screening aggregates, zeolite has a better performance.