Zeolite and activated carbon combined with biological treatment for metals removal from mixtures of landfill leachate and domestic wastewater

Current study was carried out to investigate the heavy metals removal from landfill leachate and urban wastewater by powdered activated carbon and powdered zeolite augmented SBR technique. The research was carried out in six 2000 mL breakers (working size was 1200 ml). The reactors were parted into 2 groups covering 3 for activated carbon augmented SBRs (PAC-SBR), and 3 for powdered zeolite augmented SBRs (PZE-SBR). The response surface methodology (RSM) and the central composite design (CCD) were employed to explain the most advantageous settings of the independent variables (aeration rate (l min^-1), reaction time (h), and leachate-to-wastewater mixing ration (%; v/v) and their resopnses (dependent variables including Fe, Mn, Ni and Cd). The results indicated that the PZE-SBR showed higher performance in removal efficiencies while compared to PAC-SBR. At the optimum conditions of contact time (13.83 h), aeration rate (2.81 l min^-1) and leachate to domestic wastewater proportion (20.00%) for the PZE-SBR, the removal efficiencies for Fe, Mn, Ni, and Cd were 65.65%, 61.56, 63.41%, and 60.44%, respectively.