Granular Sludge Formation in the Anaerobic Expanded Micro-Carrier Bed Process

The anaerobic expanded micro-carrier bed (MCB) process, which utilizes fine (50-100 microns) support materials as expanded bed media, was found to have the ability to cultivate granular sludge similar to that formed in the upflow anaerobic sludge blanket (UASB) process. Two laboratory-scale MCB reactors were studied with VFA and glucose wastewaters to clarify the role of the micro-carrier and the influence of substrates on granular sludge formation. Based on these results, a scale-up model with a reactor volume of 800 1 was successfully operated using molasses wastewater to demonstrate the feasibility of granular sludge formation in the MCB process.