Mixed microbial culture was isolated from heavy metals contaminated ground soils located inside iron, vinyl and cement factory area. Isolated mixed microbial culture was used for the heavy metal (Fe, Cu, Ni and Zn) removal process in horizontal rotating tubular bioreactor (HRTB). In this research, the effect of bioreactor process parameters on the bioprocess dynamics in the HRTB was studied. Results of this research have shown that profiles of heavy metals concentration were gradually reduced along HRTB for all combinations of bioreactor process parameters [inflow rates (0.5-2.0 L/h) and rotation speed (5-30 1/min)]. Hydrodynamic conditions and biomass removal capacity have main impact on the metal ions removal efficiency that was varied in the range of 38.1 % to 95.5 %. In this investigation, volumetric removal rate of metal ions (QM) was in the range of 2.408-14.989 g/L h and the highest values were observed at medium inflow rate of 2.0 L/h. On the basis of obtained results it is clear that medium inflow rate (F) has higher impact on the heavy metals removal process than bioreactor rotation speed (n). Notable pH gradient (cca 1 pH unit) along the HRTB was only observed at the inflow rate of 2.0 L/h. Results of this research have also shown that heavy metals ion removal can be successfully conducted in a HRTB as a one-step process.

Biotehnologija