Oxygen Uptake Rate Measurement Using Sigma Delta Modulator in the Biological Domain in Activated Sludge Systems

The Oxygen Uptake Rate (OUR) is an essential parameter for monitoring and evaluation of bacterial metabolism in the activated sludge system. The characterization of polluting organic compounds and the bio-degradation kinetics of organic material in the activated sludge system are evaluated as measured by OUR. In this work we propose an alternative method to measure OUR in the activated sludge system using the sigma delta modulator architecture in the biological domain. The proposed method has some advantages over existing methods. When compared to the classic method, it decreases the sampling period and improves the dynamic response. When compared to the PWM method, it introduces the benefits of noise shaping and oversampling. The performance of the proposed model is demonstrated through simulations.