Assessment of inverse fluidized bed reactor on the treatment efficiency of distillery spent wash water

The purpose of this study is to evaluate the impact of several pre-selected carrier materials used in an Inverse Fluidized Bed Reactor (IFBR) on the treatment efficiency of distillery spent wash water. Distillery spent wash water has been identified as a threat to the natural environment due to its high pollution load. The effluents from the industry are dark brown in color and contain heavy organic matter, causing a high Biochemical Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD); however, they can be treated effectively through biological processes. Previous research reveals that a high-rate anaerobic digester especially an IFBR reduces COD more effectively than other treatment technologies. The effectiveness of the reactor depends on the expansion of the fluidized bed which in turn is related to the carrier material. In this study, four different carrier materials: perlite, expanded perlite, sawdust and polystyrene, were selected. The carrier materials selected were assessed based on their efficiency in reducing COD, Total Solids (TS), Total Dissolved Solids (TDS) and Total Suspended Solids (TSS). Results were taken at 140-h Hydraulic Retention Time (HRT), with a constant Organic Loading Rate (OLR) of 12 kg COD/m3/day. Among the selected carrier materials, expanded perlite was most effective at reducing COD, TS, TDS and TSS (83.33, 72.47, 29.67 and 88.78%, respectively). This method could be easily implemented in industrial practice and thereby reduce the negative impact of production plants on the natural environment.