Abstract

A volumetric dispersion model (VDM) with inhibitory kinetics was proposed to describe the biogas production from the acetolastic methanogenesis of the acetate medium process in modeling aspects of the operating capacity and stability. The influence of axial mixing promoted by ultrasonic disruption had been investigated during the methane conversion under a progressive inhibition of substrate in the up-flow anaerobic sludge blanket (UASB) reactor. Increasing the organic loading rates was conducted for the model calibration and prediction to indicate when the process instability occurs due to a potent inhibition and suggest a proper axial mixing. For this simplified substrate characteristics investigation with controlled hydraulic retention time, the results showed that the flow and transfer system with a Peclet number of 1.254 could prevent the system failure. The process instability due to a potent inhibition could be manipulated by using suitable axial mixing to eliminate the inhibitory effect within the reactor.