Abstract
Stability aspects and dynamic behaviour of a draft-tube fluidised bed bioreactor treating phenolic effluent from a coal carbonisation plant have been investigated in the present study. Experiments were carried out to study the biodegradation of phenolic wastewater using the microorganism Pseudomonas sp., immobilised on solid support particles. The dynamics of the reactor system were monitored at various experimental conditions viz., feed (substrate) flow rates and phenol concentrations in the feed. The draft tube fluidised bed bioreactor was assumed to operate in a completely backmix mode and a model to predict the outlet phenol concentration for given inlet and equipment parameters was developed. The model equations were solved using 4 th order Runge-Kutta technique. The predictions made by the dynamic model were compared with experimental findings and the agreement between the two was good. Stability of the reactor to input disturbances was examined and it was found to be stable.