Low-temperature kinetics of anaerobic-filter wastewater treatment

Abstract

The effects of wastewater temperature on treatment efficiency in an anaerobic-filter process were examined based on laboratory data on anaerobic filters treating septic-tank effluent, dairy wastewater, slaughterhouse wastewater, potato-processing wastewater and whey wastewater. Three anaerobic filters were operated at 5, 10 and 20°C treating septic-tank effluent at different hydraulic retention times (HRTs), three anaerobic filters treating dairy wastewater were operated at 12.5, 21 and 30°C at different HRTs, an anaerobic filter treating slaughterhouse wastewater was operated at 23.6, 24.3, 25, 26.6, 26.7 and 27.1°C at different HRTs, an anaerobic filter treating potato-processing wastewater was operated at 2, 4, 10 and 20°C and an anaerobic filter treating whey wastewater was operated at 16, 20, 26 and 30°C at different HRTs. Data were analyzed for the effect of temperature using the Arrhenius equation and a relationship was developed between system temperature and first-order rate constant for each anaerobic filter system. The simple kinetic model did not fit the experimental data very well for two of the three wastewaters tested.