Start-up performance of anaerobic baffled reactor

The start-up characteristics of two lab-scale anaerobic baffled reactors with three and five compartments were investgrated in a series of tests. The baffles in the hybrid reactor affected the start-up performances. The initial organic loading COD (chemical oxygen demand) was 1.4 kg/(m3&middotd) and gradually increased to 3.5 kg/(m3&middotd) over a period of 28-63 d, after which the reactors then successfully started. The results show that the two reactors had very similar start-up performances, with the hybrid reactor starting sooner than the control reactor. The COD and volatile fatty acid concentrations decreased at lower elevations in the reactor. Scanning electron microscope images of the granular sludge suggests that the anaerobic bacteria in each compartment developed based on their available substrates and specific environmental conditions.