Performance of Inclined-Plate Settler and Activated Carbon Sponge-Cube Media Filter for the Treatment of Urban Stormwater Runoff from an Industrial Complexs

Urban stormwater runoff contributes to the deterioration of water quality of urban waterbodies. Development of a cost-effective treatment system that renders the treated effluent suitable for the recharge of receiving waterbodies meeting stringent regulations is required. This study evaluated the performances of the inclined-plate settler (IPS) and activated carbon sponge-cube media filter (ASMF) in treating urban stormwater runoff from an industrial complex area. The stormwater runoff during the first hour of rainfall had significantly high concentrations of suspended solids (SS), chemical oxygen demand (COD), and total nitrogen. The IPS and ASMF bed with hydraulic retention times of 15 ± 5 and < 3 min showed the removal efficiency of 5.4 – 33.2% and 32.8 – 95.1% for SS, turbidity, COD, and TP including < 5 – 20% for TN. The combined IPS/ASMF or biofilm (BF)-ASMF system at filtration velocity of 10 m/h showed removal efficiencies of 46.7 – 99.2% for insoluble fractions such as turbidity, COD, TP and heavy metals including < 40% for TN. The ASMF or BF-ASMF bed coupled with IPS is a cost-effective option for the treatment of urban stormwater runoff, achieving an effluent quality suitable for industrial or multipurpose reuse and for the recharge of waterbodies.