Mixing and solids accumulation in anaerobic filters. Two case studies

摘要

Results are presented which compare the anaerobic treatment of two food industry wastes, one from yeast processing and the other from ice#x2010;cream production using upflow anaerobic filters. The filters were pilot scale 25m3and 5m3in total volume respectively. Twenty eight months operating data are presented showing average monthly organic loads up to a maximum of 14 kgCODm#x2010;3d#x2010;1to the anaerobic filter treating yeast processing effluent and 11 kgCODm#x2010;3d#x2010;1to the ice cream waste filter. COD removal was consistently better than 70 from both filters. Inorganic materials from the yeast processing effluent accumulated within the filter which became progressively blocked during the three year experimental period. Critical superficial upflow velocities are indicated to avoid solids accumulation depending on the key characteristics of the effluent.