Study on Oxygen Uptake Rate Measurement

The oxygen uptake rate (OUR) measurement plays an important role in the study of kinetics parameters of activated sludge models and in wastewater characterization identification. At present the OUR is mainly determined by batch test or by using a respirometer. A simple OUR device based on the principle of OUR measurement is presented in this paper, which was proved to be feasible by a series of experiments. In the endogenous respiration test, the endogenous respiration rate and decay rate of activated sludge measured by this device were 5.1mg O2/L·h and 0.013?7h -1, respectively, which were slightly higher than those in the literature. In the substrate degradation test the OURs of the synthetic wastewater were measured, and three distinctly different OURs were measured and found to be 35mg/L·h, 13mg/L·h and 6mg/L·h representing glucose degradation, starch degradation and endogenous respiration rate, respectively. The endogenous respiration rate in the second test was higher than that in the first test, which was due to the accumulation of sludge production in the substrate degradation test. And the heterotrophic yield (Kd) was calculated to be 0.63mg VSS/mg COD, which was lower than that in the literature. The results show that this device is capable of OUR measurements.