Effects of temperature and dissolved oxygen on hydrolysis of sewer solids

Effects of temperature and dissolved oxygen (DO) on kinetics of microbial transformation processes of suspended sewer sediment particles, suspended wastewater particles and wastewater were investigated. Microbial activity was estimated by the oxygen uptake rate. The effects were studied under conditions where biomass had not acclimated to changed temperature or DO conditions. Hydrolysis processes limited the availability of organic substrates for the aerobic microbial growth. The effects of temperature were interpreted applying an Arrhenius relationship. The average Arrhenius constants found for sewer sediment particles and wastewater particles differed significantly from the average Arrhenius constant found for wastewater. The effects of dissolved oxygen concentration were interpreted applying a saturation type relationship. No differences between sewer sediment particles, wastewater particles and wastewater were found for the oxygen saturation coefficients.