Enhancing storm water runoff quality through porous concrete: characteristics, absorption isotherms and statistical analysis

The current study aimed to investigate the performance of porous concrete (PC) with varying percentages of fly ash and slag in order to enhance the quality of municipal storm water and wastewater. Firstly, the study examined the impact of incorporating different proportions (10%, 20%, 30%, and 40%) of fly ash and slag on the compressive strength, porosity, and permeability coefficient of porous concrete. After evaluating these parameters, four samples were selected from each percentage that exhibited suitable compressive strength and porosity for further qualitative tests on wastewater. Qualitative parameters including total suspended solids (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), turbidity, as well as iron (Fe) and pH levels, were measured both before and after conducting the experiments. Results revealed that adding fly ash increased the compressive strength, while they reduced the permeability coefficient and porosity and it was the opposite for slag. Finally, the porous concrete containing 10% fly ash demonstrated the highest physical characteristics and exhibited a high potential for reducing pollutants.