Multistage Soil Filter System for Rainwater Collection and Use
Rainwater collection and use is usually considered for runoff from building roofs. Runoff from impervious layers such as roads and pavements, however, has hardly been used as water supply due to its high pollutant concentration. If runoff from roads will be treated and used properly, though, it can be a good water resource and will contribute minimally to a non-point source. In this study, a multistage soil filter system (MSFS) composed of a gravel layer, a functional-media layer with zeolite, a sand layer, and a lawn layer, was developed to treat the runoff from roads and green areas. To evaluate the performance of MSFS, its removal rate of total suspended solids (TSS) was investigated based on the rainfall intensity and the thickness of each layer. The experiment results were compared with the predicted values using the MinitabTM program. The TSS removal rates ranged from 82 to 96%, with various combinations of experiment conditions. The predicted removal rates well fitted with the removal rates obtained from the experiment. An equation was formulated for predicting the TSS removal rate based on the rainfall intensity and the thickness of each layer. The optimum design factors for MSFS considering its TSS removal rate could be derived based on such equation. Based on the study results, it is expected that MSFS can contribute to securing water resources and to controlling non-point sources.
Hyungsun Kim, Jian Feng Yang, Chuleol Hee Han, Somchai Thongtem and Soo Wohn Lee
S. H. Lee et al., "Multistage Soil Filter System for Rainwater Collection and Use", Materials Science Forum, Vol. 695, pp. 622-625, 2011