Performance of fluidized bed bioreactor containing wire-mesh sponge particles in wastewater treatment

Synthetic wastewater treatment performance of a continuous-dow, fluidized bed bioreactor was investigated at different particle number densities. Porous-sponge particles surrounded by steel wires were used as support material. COD removal rate and efficiency increased from r = 1150 mg l(-1) h(-1) and E = 68% to r = 1400 mg l(-1) h(-1) and E = 96% when particle number density (PND) increased from PND = 55 l(-1) to PND = 440 l(-1) at a constant hydraulic residence time (HRT) of 9 h. The system's performance was also evaluated at different hydraulic residence times (Theta(H) = 3-9 h) With a high particle number density of PND = 670 l(-1). Synthetic wastewater used throughout the studies consisted of diluted molasses, urea, K2HPO4 and MgSO4 resulting in a ratio of COD/N/P = 100/10/1. Zooglea ramigera was the dominant microorganism in the FBBR. Apparent Monod kinetic constants of the system were determined as r(m) = 1250 mg l(-1) h(-1) and K-s = 1150 mg l(-1) by using the experimental data for PND = 670 l(-1). (C) 1997 Elsevier Science Ltd