Treatment of antibiotic fermentation-based pharmaceutical wastewater using anaerobic and aerobic moving bed biofilm reactors combined with ozone/hydrogen peroxide process

Abstract

A continuously operated laboratory scale anaerobic and aerobic moving bed biofilm reactors (MBBRs) combined with O3/H2O2 process was experimented for antibiotic fermentation-based pharmaceutical wastewater. The experimental results indicated that 26.6% of chemical oxygen demand (COD) was removed, and 931.75 mg/L of volatile fatty acids (VFAs) was produced under the optimum conditions of the anaerobic MBBR at an influent pH of 6.5, hydraulic retention time (HRT) of 12 hr and organic loading rate (OLR) of 13 kg COD/(m3·d) for the hydrolysis/acidification process. In addition, 91.0% of COD was removed at 1.5 m3/h of aeration rate with the aerobic MBBR. The shape of bacteria inside the bio-carriers was characterized by a scanning electron microscope. The anaerobic MBBR bacteria were observed as long bacilli, and the aerobic MBBR bacteria were observed as mainly cocci and short bacilli. Finally, the residual non-biodegraded pollutants were mineralized by O3/H2O2 oxidation with 0.5 of H2O2/O3 molar ratio and 15 min of reaction time. The total removal efficiencies of COD and color reached 99.2 and 98.7%, respectively. Thus, this method might offer an effective way to treat wastewater from the pharmaceutical industry. © 2013 American Institute of Chemical Engineers.