Department of Civil Engineering, Kyung Hee University, Yongin, Korea.
Construction and Environment Research Division, Expressway and Transportation Research Institute, Korea Expressway Corporation, Hwaseong, Korea.
Environ Sci Pollut Res Int. 2019 Jan;26(2):1192-1207. doi: 10.1007/s11356-017-0192-y. Epub 2017 Sep 19.
Road-deposited sediments (RDS) on an expressway, residual RDS collected after sweeping, and RDS removed by means of sweeping were analyzed to evaluate the degree to which sweeping removed various non-point source contaminants. The total RDS load was 393.1 ± 80.3 kg/km and the RDS, residual RDS, and swept RDS were all highly polluted with organics, nutrients, and metals. Among the metals studied, Cu, Zn, Pb, Ni, Ca, and Fe were significantly enriched, and most of the contaminants were associated with particles within the size range from 63 μm to 2 mm. Sweeping reduced RDS and its associated contaminants by 33.3-49.1% on average. We also measured the biological oxygen demand (BOD) of RDS in the present work, representing to our knowledge the first time that this has been done; we found that RDS contains a significant amount of biodegradable organics and that the reduction of BOD by sweeping was higher than that of other contaminants. Significant correlations were found between the contaminants measured, indicating that the organics and the metals originated from both exhaust and non-exhaust particles. Meanwhile, the concentrations of Cu and Ni were higher in 63 μm-2 mm particles than in smaller particles, suggesting that some metals in RDS likely exist intrinsically in particles, rather than only as adsorbates on particle surfaces. Overall, the results in this study showed that sweeping to collect RDS can be a good alternative for reduction of contaminants in runoff.
对高速公路上的道路沉积物（RDS）、清扫后残留的 RDS 和通过清扫去除的 RDS 进行了分析，以评估清扫去除各种非点源污染物的程度。RDS 的总负荷为 393.1±80.3kg/km，RDS、残留 RDS 和清扫 RDS 均受到有机物、养分和金属的高度污染。在所研究的金属中，Cu、Zn、Pb、Ni、Ca 和 Fe 明显富集，大部分污染物与粒径在 63μm 至 2mm 之间的颗粒有关。清扫平均减少了 33.3-49.1%的 RDS 及其相关污染物。我们还在本工作中测量了 RDS 的生物需氧量（BOD），据我们所知，这是首次进行此类测量；我们发现 RDS 含有大量可生物降解的有机物，并且清扫对 BOD 的减少高于对其他污染物的减少。所测量的污染物之间存在显著相关性，表明有机物和金属既来自尾气颗粒，也来自非尾气颗粒。同时，63μm-2mm 颗粒中的 Cu 和 Ni 浓度高于较小颗粒中的浓度，表明 RDS 中的一些金属可能固有地存在于颗粒中，而不仅仅是作为颗粒表面的吸附物存在。总的来说，本研究的结果表明，收集 RDS 的清扫可以作为减少径流中污染物的一种很好的替代方法。
