CHARACTERIZATION OF IMMOBILIZED CELLS IN BIODEGRADATION OF ABS RESIN MANUFACTURING WASTE-WATER

Because of the presence of refractory and biologically inhibitory orga nic compounds in ABS resin wastewater, which would retard the bioactiv ity of the autotrophic nitrifier and make the efficiency of nitrificat ion process unstable, the application of cell immobilization for ABS w astewater treatment has been investigated by immobilizing the enrichme nt culture of nitrifying bacteria with alginate. The characterization of the immobilized cells in various alignate concentrations was conduc ted by a series of biodegradability studies with electrolytic respirom etry and compared with the differences from the dispersed cells.Result s clearly indicated that immobilized cells achieved higher efficiency of COD and TKN removal than that of the dispersed cells during the per iod of high initial concentration of wastewater. Meanwhile, high conce ntration of cells were growing near the gel surface and reduced the ef fects of diffusional restriction. No remarkable difference was found w hile the concentration of alginate ranged from 3% to 5%. According to mass balance of total nitrogen, more than 25% of total nitrogen was re moved in the batch system of the immobilized cell. Simultaneous nitrif ication and denitrification could occur due to the oxygen gradient thr oughout the gel matrix. Compared with the complete mixing system of th e dispersed cell, the approach for the immobilized-cell system provide d a more effective method for treating the special wastewater with hig h strength of nitrogenous and inhibitory compounds. Copyright (C) 1996 IAWQ.