Water purification characteristics of pervious concrete fabricated with CSA cement and bottom ash aggregates

The water purification characteristics of pervious concrete fabricated with calcium sulfoaluminate cement and coal bottom ash aggregate are investigated. Reduction ratio of nitrogen and phosphorus by the pervious concrete was investigated, and the results were discussed with filtering and adsorption effects. A series of tests including a batch adsorption, BET and XRD was conducted for this purpose. The calcium sulfoaluminate cement contributed to the slightly rapid strength development of the pervious concrete, while its purification performance was similar to that of ordinary Portland cement. Suspended nitrogen and phosphorous contents were significantly reduced by the physical filtration of voids in the pervious concrete, resulting in an improvement of the turbidity. The dissolved phosphorous could be adsorbed by the formation of hydroxyapatite in both cements.