Abstract
In this study, the influence of ceramsite particle size was evaluated in treating low-pollution water obtained from the enclosed landscape water body. Ceramsites with varied particle sizes (2-4 mm, 4-8 mm and 8-16 mm) were valued for their pollutants removal performance. After the 6-day treatment of 2-4 mm and 4-8 mm ceramsites, the turbidity, surface color, and true color of the low-polluted water dropped to below 2 NTU, 7 degrees, and 4 degrees, respectively. The per-manganate index of 4-8 mm and 2-4 mm treated water were 5.7 mg/L and 5.2 mg/L, respectively. 4-8 mm ceramsites also have an excellent removal effect on DOC, and their value dropped to 4.5 mg/L, with a corresponding removal rate reaching 62.1% after 6 days of operation. As with other indicators, the UV254, UV280, E250/E365 and CDOM of the water treated with 2-4 mm and 4-8 mm ceramsites were also much better than those treated with 8-16 mm ceramsites. According to the three-dimensional fluorescence spectrum, 8-16 mm ceramsites also have a poor humic acid removal effect. Considering the clogging problem, it was recommended to choose 4-8 mm ceramsites using for low-pollution water treatment.
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