THE ADVANTAGES OF PERIODICALLY OPERATED BIOFILM REACTORS FOR THE TREATMENT OF HIGHLY VARIABLE WASTE-WATER

Many wastes generated by industry, at hazardous wastes sites and at la ndfills experience shock loads of inhibitory organic compounds which c an upset biological treatment systems. Biofilm reactors can be used to treat these wastes. However, the continuous now mode operation normal ly used results in biofilm stratification and uneven biomass distribut ion that limits the ability of biofilm processes to treat shock loads. Periodic operation of biofilm reactors is advantageous because even b iomass distribution can be obtained. In addition, data from membrane s equencing batch biofilm reactors indicates that periodic operation imp oses regular variations in substrate concentration on the biofilm. As a result, organisms throughout the film achieve maximum growth rates w hich cause physiological adaptations that can improve biofilm response to shock loads. Copyright (C) 1996 IAWQ.