Nitrous oxide (N2O) is a strong greenhouse gas with a significantly higher global warming potential than carbon dioxide. N2O is also produced by wastewater treatment plants during the biological nitrogen removal process. Recent efforts to reduce the energy footprint have favored contemporary nitrogen removal processes such as deammonification (nitritation/annamox). Unfortunately, there is evidence that operating conditions of these processes can result in N2O emissions that are much higher than conventional treatment
processes. Due to the lack of comprehensive monitoring approaches there is limited data available to establish quantitative relationships between nitrous oxide emissions and process parameters of biological nitrogen conversions. Current monitoring systems are using either Fourier-transform-infrared based gas analyzers or in-situ N2O probes for aqueous samples, which exhibit slow signal responses, target only N2O rather than a wider spectrum of relevant
gases simultaneously, and due to their high unit costs allow measurements in only single locations. Thus, these monitoring devices are not suitable to comprehensively control the spatially distributed generation of nitrous gas emissions. Therefore, the goals of this project are to develop novel monitoring and control strategies for N2O employing photoacoustic laser spectroscopy enabling a tight control of contemporary nitrogen removal processes while also
enabling new ways in harvesting N2O for enhanced energy recovery from waste streams.