Factual analysis of granule flotation in brewery wastewater treatment plants by the fluorescence in situ hybridization method.

The factors that change the microbial distribution and consequently the flotation of brewery granules were investigated using laboratory-scale upflow anaerobic sludge blanket (UASB) reactors and the fluorescence in situ hybridization (FISH) method. The startup operations of laboratory-scale UASB reactors fed with acetate-based synthetic wastewater, in which the loading rate was maintained at 0.1 gCOD/gVSS/d (Run 1) and increased in a stepwise manner from 0.

Microbial analyses by fluorescence in situ hybridization of well-settled granular sludge in brewery wastewater treatment plants.

The characteristics of granular sludge from full-scale upflow anaerobic sludge blanket reactors used for the treatment of brewery wastewater were investigated. Fluorescence in situ hybridization (FISH) analyses of settled granules from a reactor that had been treating brewery wastewater stably at COD removal rates of over 90% for more than 6 months showed that a methanogen of the genus Methanosaeta was predominant near the granule surface and that Bacteria were not abundant. The center of the granules was composed of dead or resting cells, or both, which were used as a support for active archaeal and bacterial cells near the surface.