BIOLOGICAL PHENOL DEGRADATION BY IMMOBILIZED-CELLS OF Pseudomonas putida IN A THREE-PHASE FLUIDIZED BIOREACTOR

This paper presents a study of the aerobic treatment of synthetic wastewater, in which phenol is the only source of carbon at a three-phase fluidized bed reactor. The fine sand (0.25 mm diameter) is used to support the biofilm, which is mainly set up with Pseudomonas putida. The system was operated at a controlled temperature around 29 ºC, during 488 days, under different operating conditions: affluent phenol concentration between 51.3 and 1588.3 mg/l, hydraulic retention times from 0.54 to 7.01 h, and superficial air velocity from 0.9 and 1.8 cm/s. In the range of source carbon investigated, organic loading rates ranging from 2.20 to 6.44 kg phenol/m3.day (from 5.32 to 15.52 Kg COD/m3.day) were concerned. It was observed a phenol biodegradation efficiency between 87.2 % and 98.8 %. From the results reported in this paper, it is adequate to consider this b oreactor technically suitable for the phenol biodegradation from wastewaters. Palabras clave: wastewater treatment, phenol biodegradation, fluidized bed bior actor, phenolic wastewater, three phase fluidizatio