Mechanisms of Microbial Detachment during Biological Filtration and Backwashing

摘要

Biological Filtration may become an essential part of drinking water treatment inthe United States during the next several decades. Since biological granular activated carbon (GAC) filters accumulate both biological and non-biological particles on the filter bed, the differences in the detachment of these groups of particles during backwashing will be an important aspect of operation of these filters. This study presents the results of an analysis of the detachment of particles from biofilms in terms of a microscopic force model and the evaluation of this model with results from operation of a pilot filter. Experiments on attachment and detachment were completed in a packed glass column with GAC/sand media and an indigenous bacterial population. The operation of a biological filter was simulated by using filter influent (nonchlorinated) water from the nearby Water Treatment Plant with the addition of a carbon source.