IMPLEMENTATION OF A CONTINUOUS-FLOW STIRRED BIOREACTOR SYSTEM IN THE BIOREMEDIATION OF HEAVY-METALS FROM INDUSTRIAL-WASTE WATER

The industrial applicability of immobilized non-viable yeast biomass ( Saccharomyces cerivisiae) in continuous-flow stirred bioreactors was t ested with respect to metal removal from electroplating effluent solut ions containing Cu, Cd, Cr, Ni and Zn in excess of the stipulated wate r quality criteria. Two systems, a dual bioreactor and triple bioreact or system in series, were tested and compared regarding their efficien cy of metal removal. The system containing two bioreactors linked in s eries provided a more efficient solution to the problem. The introduct ion of a third bioreactor into the system had a marginal effect on the amount of metal removed. Subsequent to treatment within the bioreacto rs the levels of Cu, Cr and Ni in the effluent complied with the stipu lated drinking water quality criteria and, although in excess of these criteria only 18% of the initial Zn and 17% of the Cd remained in sol ution. (C) 1997 Elsevier Science Ltd.