Microalgal biomass can be converted to biofuels to replace nonsustainable fossil fuels, but the widespread use of microalgal biofuels remains hampered by the high energetic and monetary costs related to carbon dioxide supply and downstream processing. Growing microalgae in mixed culture biofilms reduces energy demands for mixing, maintaining axenic conditions, and biomass concentration. Furthermore, maintaining a high pH improves carbon dioxide absorption rates and inorganic carbon solubility, thus overcoming the carbon limitation and increasing the volumetric productivity of the microalgal biomass.
View Article and Find Full Text PDFDuring nitrogen removal in conventional activated sludge processes, nitrous oxide can be emitted. With a global warming potential of 298 CO2-equivalents it is an important greenhouse gas that affects the sustainability of wastewater treatment. The present study reports nitrous oxide emission data from a 16 month monitoring campaign on a full-scale municipal wastewater treatment.
View Article and Find Full Text PDFMethane is a potent greenhouse gas and its emission from municipal wastewater treatment plants (WWTPs) should be prevented. One way to do this is to promote the biological conversion of dissolved methane over stripping in aeration tanks. In this study, the well-established Activated Sludge Model n°1 (ASM1) and Benchmark Simulation Model n°1 (BSM1) were extended to study the influence of process design and operating parameters on biological methane oxidation.
View Article and Find Full Text PDFIn the last few years, the emission of nitrous oxide from wastewater treatment plants has become a topic of increased interest, given its considerable impact on the overall climate footprint of wastewater treatment plants. Various sampling strategies to estimate nitrous oxide emission from wastewater treatment plants have been applied in different studies. The present study addresses the influence of sampling strategies on the estimated emission by analysing the variability of an extensive dataset of nitrous oxide emissions resulting from a long-term online monitoring campaign at a full-scale municipal wastewater treatment plant.
View Article and Find Full Text PDFMunicipal wastewater treatment plants emit methane. Since methane is a potent greenhouse gas that contributes to climate change, the abatement of the emission is necessary to achieve a more sustainable urban water management. This requires thorough knowledge of the amount of methane that is emitted from a plant, but also of the possible sources and sinks of methane on the plant.
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