Start-up of modified anaerobic baffled reactor for the treatment of landfill leachate by using granular sludge

Abstract

The objective of this study was to valuate the start-up performance of the Modified Anaerobic Baffled Reactor (MABR) system by using granular sludge treating landfill leachate. Anaerobic reactor start-up is a complex process as it depends on the substrate characteristics, working conditions, inoculum and reactor configuration. To reduce the start-up time and have better operational parameters control in anaerobic processes, important factors are needed to enhance the high-rate anaerobic systems efficiency. Sludge granulation was indeed an achievement in anaerobic wastewater treatment technology and has greatly enhanced its efficiency and applicability. It holds many advantages, such as mutual defence against antagonists, efficient reactor operation without sludge washout, and effluent with low suspended solids. Granules are the functional units which comprise different microorganisms that are required for the methanogenic degradation of organic matter. Results from this study showed a successful start-up of the MABR system at an organic loading rate (OLR) of 0.0875 kgCOD/m3/d and hydraulic retention time (HRT) of four days. During this period the Chemical Oxygen Demand (COD) removal efficiency was 99 % and the gas production increased steadily from 0.013 L/d to 0.021 L/d.