Sønderup Melanie J, Egemose Sara, Bochdam Timm, Flindt Mogens R
Department of Biology, University of Southern Denmark, Campusvej 55, 5230, Odense M, Denmark.
Arwos A/S, Forsyningsvejen 2, 6200, Aabenraa, Denmark.
Environ Monit Assess. 2015 Dec;187(12):758. doi: 10.1007/s10661-015-4975-7. Epub 2015 Nov 18.
Traditional wet detention ponds and sand filters remove particles efficiently, whereas only a minor part of the dissolved and bioavailable load is removed. To improve the retention of dissolved substances, we tested crushed concrete as a filter material simultaneously with a traditional sand filter placed after an existing wet pond. The particulate fractions (particles, organic matter, phosphorus, and heavy metals) were removed efficiently in the pond and both filter materials, with the concrete filter often being best seen over a year. Dissolved heavy metals (lead (Pb), nickel (Ni), copper (Cu), chromium (Cr), and cadmium (Cd)) were largely retained, though a washout was observed from the pond (Ni and Cu), concrete filter (Cr), and sand filter (Ni) during the first month. The pond only retained total dissolved phosphorus (TDP) during summer. Crushed concrete and sand had a high (>70%) retention of TDP within the first months of operation, but the retention dropped in both filters due to a large oil load into the system (4 kg impermeable ha(-1) in 1 month). The poor retention might to some degree be due to mineralization processes turning particulate phosphorus (PP) into TDP. The massive oil load was retained efficiently (99.3%) in the pond and both filters, clearly illustrating that both filter materials were able to retain either oil or TDP. An additional pilot study showed that at residence times of 1 h, crushed concrete bound 90% TDP whereas sand only bound 22% TDP. Retention of TDP and PP decreased with shorter residence time in both materials, but fastest in sand.
传统的湿式滞留池和砂滤器能有效去除颗粒物质，而溶解态和生物可利用态污染物只有一小部分被去除。为了提高溶解物质的截留率，我们测试了碎混凝土作为过滤材料，并在现有湿式滞留池后设置了传统砂滤器。颗粒组分（颗粒、有机物、磷和重金属）在滞留池和两种过滤材料中都能被有效去除，碎混凝土滤器在一年的时间里通常表现最佳。溶解态重金属（铅（Pb）、镍（Ni）、铜（Cu）、铬（Cr）和镉（Cd））大部分被截留，不过在第一个月观察到从滞留池（镍和铜）、碎混凝土滤器（铬）和砂滤器（镍）中有淋失现象。滞留池仅在夏季截留总溶解磷（TDP）。碎混凝土和砂在运行的头几个月对TDP的截留率很高（>70%），但由于系统中大量的油负荷（1个月内4 kg不透水公顷(-1)），两种滤器的截留率都下降了。截留效果不佳在一定程度上可能是由于矿化过程将颗粒态磷（PP）转化为TDP。大量的油负荷在滞留池和两种滤器中都被有效截留（99.3%），清楚地表明两种过滤材料都能够截留油或TDP。另一项试点研究表明，在停留时间为1小时的情况下，碎混凝土能截留90%的TDP，而砂只能截留22%的TDP。两种材料中TDP和PP的截留率都随停留时间缩短而降低，但砂中下降最快。
