Comparison of Denitrification Induced by Various Organic Substances—Reaction Rates, Microbiology, and Temperature Effect

Widespread groundwater pollution with nitrate (NO3?) and the finite decreasing geogenic NO3? degradation capacity in aquifers require a better understanding of potential treatment methods. This project aimed at exploring comparing efficiency four organic substances as electron donors for heterotrophic denitrification. Circulation column experiments using sediment without high agricultural were conducted. Acetate, glucose, ascorbic acid, ethanol added to these columns three concentration steps induce biological denitrification, whereby also temperature dependence denitrification rates (room typical 10°C) was taken into account. Results show all carbon (C) sources intensities varying considerably between donors. Comparison two approaches shows substantial differences applied indicates T an important variable Ethanol is clearly most effective donor biodenitrification investigated this study, stronger more 10°C than room temperature. In contrast, much higher reaction are achieved glucose temperature, compared 10°C. Denitrification acid very low both temperatures; its addition produces biomass which repeatedly led clogging. entire test series, nitrite (NO2?) accumulation occurred frequently concentrations Analysis microorganisms strong modification microbial community different C well approaches.