Biodegradation of organic content in wastewater in fluidized bed bioreactor using low-density biosupport

Abstract

In this study, a new biocarrier made up of low-density polypropylene of surface area 524 mm2 per particle and of density 870 kg/m3 was used in the treatment of wastewater using fluidized bed reactor. Holdup studies were performed for various bed heights (0.2–0.8 m) to predict the operating conditions. The effect of bed height (0.6, 0.8, and 1 m), hydraulic retention time (6.25, 8.33, 12.5, and 24 h), superficial gas velocity (0.0016, 0.00212, 0.00265, and 0.00318 m/s), and concentration (910, 1,820, 2,840, and 3,940 mg/l) on the percentage of COD reduction were studied. For bed height of 0.8 m, optimum holdup and maximum COD reduction was obtained. From the results, it was observed that percentage of COD reduction was increased with the increase in superficial gas velocity but it was decreased with the decrease in initial concentration. A maximum COD reduction of 96.7% at a superficial gas velocity of 0.00318 m/s was obtained for a wastewater of concentration of 910 mg/l and HRT of 24 h.