Nitrogen Recovery from Wastewater: Possibilities, Competition with Other Resources and Adaptation Pathways

Due to an increased food production the demand for nitrogen and phosphorus as fertilizers grows. Nitrogen based fertilizers are produced with the Haber-Bosch process through industrial fixation of N2 into ammonia. Through wastewater treatment the nitrogen is finally released back to the atmosphere as N2 gas. This nitrogen cycle is characterized...

Ensemble predictions of hydro-biogeochemical fluxes at the landscape scale

Model predictions of biogeochemical fluxes on the landscape scale are highly uncertain, both with respect to stochastic (parameter) and structural uncertainty. The idea of our ensemble modelling approach is to reduce the predictive uncertainty by covering part of the parameter and model structural uncertainty. In this study 4 different models...

Characterization of second generation biomass under thermal conversion and the fate of nitrogen

This dissertation deals with the characterization of several biomass materials under thermal conversion conditions using small--scale equipment. The fuels are tested under the conditions of slow and fast heating rate pyrolysis and combustion, with the main goal of investigating the chemistry of fuel--bound nitrogen. New energy policies put...

Electrochemical Ammonia Synthesis: Hydrogen Permeable Electrodes as Alternative Pathway for Nitrogen Reduction

In the last century, the indiscriminate use of fossil energy to power the industrial revolution and technological progress of humankind, has led to the depletion of limited natural resources and, most importantly, the emission and accumulation of alarming levels of pollutants and greenhouse gases (GHG) in the atmosphere. One of the major...

Biological performance and sludge filterability of anaerobic membrane bioreactors under nitrogen limited and supplied conditions

The impact of nitrogen on biological performance and sludge filterability of anaerobic membrane bioreactors was investigated in two lab-scale cross-flow anaerobic membrane bioreactors that were fed with cheese whey at two different COD:TKN ratios (50 and 190). Nitrogen deprivation adversely affected the biological treatment performance and...

Nitrogen recovery from wastewater: Possibilities, competition with other resources, and adaptation pathways

Due to increased food production, the demand for nitrogen and phosphorus as fertilizers grows. Nitrogen-based fertilizers are produced with the Haber-Bosch process through the industrial fixation of N2 into ammonia. Through wastewater treatment, the nitrogen is finally released back to the atmosphere as N2 gas. This nitrogen cycle is...

Integrated resource recovery from aerobic granular sludge plants

The study evaluated the combined phosphorus, nitrogen, methane, and extracellular polymeric substances (EPS) recovery from aerobic granular sludge (AGS) wastewater treatment plants. About 30% of sludge organics are recovered as EPS and 25–30% as methane (≈260 ml methane/g VS) by integrating alkaline anaerobic digestion (AD). It was shown that...