Determination of biodegradation kinetics of bacterial storage organic substrates through electrolytic respirometry

Biodegradation kinetics of bacterial storage substrates can be of prime importance to designing some bioprocesses. as for example biological phosphorus removal. In this work, kinetic parameters of polyhydroxyalcanoates degradation, stored into phosphorus accumulating organisms, were determined through electrolytic respirometry. An experimental procedure, based on anaerobic substrate storage followed by respirometrically-measured aerobic degradation, was used. A lot of experimental data points were easily obtained but a reference test was neccesary in order to remove interferences of other oxygen consuming events. Oxygen uptake simulation curves were obtained through a non linear fitting estimation method, using a mathematical model that described substrate consumption and biomass growth and decay. Simulation curves correlated well with oxygen uptake data, and the parameters obtained (mu (max), K-s, b and Y) were similar to the ones obtained by several authors.