Abstract

One of the important concerns in Tehranmunicipal landfill is the production of leachate and its potentialfor water resources pollution. This paper investigates theremoval of heavy metals from landfill leachate by using acombined system of a membrane Bioreactor (MBR) togetherwith reverse osmosis. The leachate was collected from a landfillin the vicinity of Tehran nearly 1 year old, The data indicatedthat the system provided high removals of Fe, Ni, Cu, Zn, Pb, Cdand Cr equal to 98%, 79%, 85%, 85%, 87%, 82%, and 73%respectively and heavy metal concentration in MBR effluent is afunction of aeration ratio and bioaccumulation. Among themetals investigated in the present study It can be concluded thatthe extracellular adsorption, is the principal removal process ofthe metals, compared to other removal mechanisms such asbioaccumulation or intracellular accumulation, Cu, Cr, Ni, Pb,Cd, Zn, and Fe, respectively, have higher capability of beingadsorbed through biological processes by MLSS. Also, based onFreundlich Isotherm, Cr, Cd, Pb, Cu, Zn, and Fe, in turn, havethe most saturation rate for every gram of MLSS and theirmaximum fast absorption is 0.000023, 0.0035, 0.22, 5, 6, 130mg/g MLSS, respectively.