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Konrad Koch - One of the best experts on this subject based on the ideXlab platform.
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nitrogen removal and intentional Nitrous Oxide Production from reject water in a coupled nitritation Nitrous denitritation system under real feed stream conditions
Bioresource Technology, 2018Co-Authors: M Weisbach, Paul Thiel, Jörg E. Drewes, Konrad KochAbstract:A Coupled Aerobic-anoxic Nitrous Decomposition Operation (CANDO) was performed over five months to investigate the performance and dynamics of nitrogen elimination and Nitrous Oxide Production from digester reject water under real feed-stream conditions. A 93% conversion of ammonium to nitrite could be maintained for adapted seed sludge in the first stage (nitritation). The second stage (Nitrous denitritation), inoculated with conventional activated sludge, achieved a conversion of 70% of nitrite to Nitrous Oxide after only 12 cycles of operation. The development of an alternative feeding strategy and the addition of a coagulant (FeCl3) facilitated stable operation and process intensification. Under steady-state conditions, nitrite was reliably eliminated and different Nitrous Oxide harvesting strategies were assessed. Applying continuous removal increased N2O yields by 16% compared to the application of a dedicated stripping phase. These results demonstrate the feasible application of the CANDO process for nitrogen removal and energy recovery from ammonia rich wastewater.
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Nitrogen removal and intentional Nitrous Oxide Production from reject water in a coupled nitritation/Nitrous denitritation system under real feed-stream conditions.
Bioresource technology, 2018Co-Authors: M. Weißbach, Paul Thiel, Jörg E. Drewes, Konrad KochAbstract:A Coupled Aerobic-anoxic Nitrous Decomposition Operation (CANDO) was performed over five months to investigate the performance and dynamics of nitrogen elimination and Nitrous Oxide Production from digester reject water under real feed-stream conditions. A 93% conversion of ammonium to nitrite could be maintained for adapted seed sludge in the first stage (nitritation). The second stage (Nitrous denitritation), inoculated with conventional activated sludge, achieved a conversion of 70% of nitrite to Nitrous Oxide after only 12 cycles of operation. The development of an alternative feeding strategy and the addition of a coagulant (FeCl3) facilitated stable operation and process intensification. Under steady-state conditions, nitrite was reliably eliminated and different Nitrous Oxide harvesting strategies were assessed. Applying continuous removal increased N2O yields by 16% compared to the application of a dedicated stripping phase. These results demonstrate the feasible application of the CANDO process for nitrogen removal and energy recovery from ammonia rich wastewater.
Valerie Michotey - One of the best experts on this subject based on the ideXlab platform.
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Denitrification : An important Pathway for Nitrous Oxide Production in Tropical Mangrove Sediments (Goa, India)
Journal of environmental quality, 2010Co-Authors: Sheryl Oliveira Fernandes, Patricia Bonin, P. A. Loka Bharathi, Valerie MichoteyAbstract:Net Nitrous Oxide Production and denitrification activity were measured in two mangrove ecosystems of Goa, India. The relatively pristine site Tuvem was compared to Divar which is prone to high nutrient input. Stratified sampling at 2 cm intervals within the 0-10 cm depth range showed that N2O Production at both the locations decreased with depth. Elevated denitrification activity at Divar resulted in maximum Production of up to 1.95 nmol N2O-N g -1 h -1 at 2-4 cm which was 3 times higher than at Tuvem. Detailed investigations to understand the major pathway contributing to Nitrous Oxide Production carried out at Tuvem showed that incomplete denitrification was responsible for up to 43-93% of N2O Production. N2O Production rates closely correlated to nitrite concentration (n=15; r=-0.47; p
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denitrification an important pathway for Nitrous Oxide Production in tropical mangrove sediments goa india
Journal of Environmental Quality, 2010Co-Authors: Sheryl Oliveira Fernandes, Patricia Bonin, P Loka A Bharathi, Valerie MichoteyAbstract:Net Nitrous Oxide Production and denitrification activity were measured in two mangrove ecosystems of Goa, India. The relatively pristine site Tuvem was compared to Divar which is prone to high nutrient input. Stratified sampling at 2 cm intervals within the 0-10 cm depth range showed that N2O Production at both the locations decreased with depth. Elevated denitrification activity at Divar resulted in maximum Production of up to 1.95 nmol N2O-N g -1 h -1 at 2-4 cm which was 3 times higher than at Tuvem. Detailed investigations to understand the major pathway contributing to Nitrous Oxide Production carried out at Tuvem showed that incomplete denitrification was responsible for up to 43-93% of N2O Production. N2O Production rates closely correlated to nitrite concentration (n=15; r=-0.47; p<0.05) and denitrifier abundance (r=0.55; p<0.05) suggesting that nitrite utilisation by microbial activity leads to N2O Production. Nitrous Oxide Production through nitrification was below detection affirming that denitrification is the major pathway responsible for Production of the greenhouse gas. Net N2O Production in these mangrove systems are comparatively higher than those reported from other natural estuarine sediments and therefore warrant mitigation measures.
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Determination of the bacterial processes which are sources of Nitrous Oxide Production in marine samples.
Water Research, 2002Co-Authors: Patricia Bonin, Christian Tamburini, Valerie MichoteyAbstract:Abstract Partial denitrification and the initial step of nitrification are the main biological processes which produce Nitrous Oxide. In order to determine the contribution that these processes have in Nitrous Oxide Production, the efficiency of different inhibitors on nitrifying activity has been tested, and the effect on denitrifying activity has been investigated, using culture strains and natural marine samples. A good nitrification inhibitor should not affect denitrification. A low partial pressure of C 2 H 2 provided the best conditions, inhibiting 75%, Nitrosococcus oceanus (culture sample) and 100% (natural sample) of the nitrifying activity and having only a small inhibitory effect (12%) on denitrifying activity. These conditions have been applied on samples from the dilution plume of the Rhone River, an area characterized as a source of Nitrous Oxide. Using these inhibitors, it has been shown that in this area, incomplete denitrification is the main process producing Nitrous Oxide in the surface layers at the mouth of the river and in the bottom nepheloid layer, whereas in the marine surface layer the dominant process is nitrification.
Angus J. P. Ferguson - One of the best experts on this subject based on the ideXlab platform.
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The impact of suspended oyster farming on nitrogen cycling and Nitrous Oxide Production in a sub-tropical Australian estuary
Estuarine Coastal and Shelf Science, 2017Co-Authors: Dirk V. Erler, David T. Welsh, William W. Bennet, Tarik Meziane, Cédric Hubas, Daniele Nizzoli, Angus J. P. FergusonAbstract:In this study we quantified nitrate (NO3−) reduction (denitrification, anammox and DNRA) and N2O Production in sediments and epibiont communities associated with Sydney Rock Oyster (Saccostrea glomerata) farming. In sediments beneath an active suspended oyster farm, DNRA accounted for 98% of NO3− reduction with rates of up to 169 ± 45 μmol N m−2 h−1. Much of this DNRA was fuelled by NO3− derived from nitrification. Reference sediments had significantly lower DNRA rates of 83.8 ± 28.2 μmol N m−2 h−1, however this constituted 96% of the sites total NO3− reduction. Fatty acid analysis showed that sediment organic matter was more labile in the oyster impacted sediments, facilitating subtle shifts in sediment oxygen demand which increased the Fe2+ availability with respect to the reference sediments. The difference in DNRA rate between the sites was attributed to autotrophic oxidation of soluble Fe2+ in sediments underlying the oyster cultures. DNRA was absent in the oyster shell epibiont communities and rates of anammox and denitrification were lower than in the sediments. Production of NH4+ from the oysters and their associated epibionts was larger than DNRA and reached a rate of 206.2 μmol N m−2 h−1. Nitrous Oxide Production rates were generally low compared to other aquaculture systems and the net flux of N2O for the combined oyster cultivation system (i.e. sediments plus epibionts) was negative, i.e. there was N2O consumption in the sediments beneath the oysters. Overall, subtropical suspended oyster farming systems favour inorganic N retention over N loss.
Birger Ulf Hansen - One of the best experts on this subject based on the ideXlab platform.
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High Nitrous Oxide Production from thawing permafrost
Nature Geoscience, 2010Co-Authors: Bo Elberling, Hanne H. Christiansen, Birger Ulf HansenAbstract:The impact of thawing permafrost on the nitrogen cycle is uncertain. Laboratory experiments using permafrost cores from northeast Greenland reveal that rewetting of thawed permafrost increases Nitrous Oxide Production over 20-fold. Permafrost soils contain nearly twice as much carbon as the atmosphere1. When these soils thaw, large quantities of carbon are lost, mainly in the form of methane and carbon diOxide1,2,3,4,5,6,7,8,9. In contrast, thawing is thought to have little impact on Nitrous Oxide emissions, which remain minimal following the summer thaw4. Here, we examined the impact of thawing on Nitrous Oxide Production in permafrost cores collected from a heath site and a wetland site in Zackenberg, Greenland. Rates of Nitrous Oxide Production in the heath soil were minimal, regardless of the hydrological conditions. Although rates of Nitrous Oxide Production in the wetland soil were low following thawing, averaging 1.37 μg N h−1 kg−1, they were 18 μg N h−1 kg−1 for permafrost samples following thawing, drainage and rewetting with the original meltwater. We show that 31% of the Nitrous Oxide produced after thawing and rewetting a 10-cm permafrost core—equivalent to 34 mg N m−2 d−1—was released to the atmosphere; this is equivalent to daily Nitrous Oxide emissions from tropical forests on a mean annual basis 10. Measurements of Nitrous Oxide Production in permafrost samples from five additional wetland sites in the high Arctic indicate that the rates of Nitrous Oxide Production observed in the Zackenberg soils may be in the low range.
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Erratum: High Nitrous Oxide Production from thawing permafrost
Nature Geoscience, 2010Co-Authors: Bo Elberling, Hanne H. Christiansen, Birger Ulf HansenAbstract:Nature Geoscience 3, 332–335 (2010); published online: 4 April 2010; corrected after print: 26 May 2010. In the version of this Letter originally published, Fig. 2b was incorrect and should have been as shown here. This error has been corrected in the HTML and PDF versions of the Letter.
Paul Thiel - One of the best experts on this subject based on the ideXlab platform.
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nitrogen removal and intentional Nitrous Oxide Production from reject water in a coupled nitritation Nitrous denitritation system under real feed stream conditions
Bioresource Technology, 2018Co-Authors: M Weisbach, Paul Thiel, Jörg E. Drewes, Konrad KochAbstract:A Coupled Aerobic-anoxic Nitrous Decomposition Operation (CANDO) was performed over five months to investigate the performance and dynamics of nitrogen elimination and Nitrous Oxide Production from digester reject water under real feed-stream conditions. A 93% conversion of ammonium to nitrite could be maintained for adapted seed sludge in the first stage (nitritation). The second stage (Nitrous denitritation), inoculated with conventional activated sludge, achieved a conversion of 70% of nitrite to Nitrous Oxide after only 12 cycles of operation. The development of an alternative feeding strategy and the addition of a coagulant (FeCl3) facilitated stable operation and process intensification. Under steady-state conditions, nitrite was reliably eliminated and different Nitrous Oxide harvesting strategies were assessed. Applying continuous removal increased N2O yields by 16% compared to the application of a dedicated stripping phase. These results demonstrate the feasible application of the CANDO process for nitrogen removal and energy recovery from ammonia rich wastewater.
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Nitrogen removal and intentional Nitrous Oxide Production from reject water in a coupled nitritation/Nitrous denitritation system under real feed-stream conditions.
Bioresource technology, 2018Co-Authors: M. Weißbach, Paul Thiel, Jörg E. Drewes, Konrad KochAbstract:A Coupled Aerobic-anoxic Nitrous Decomposition Operation (CANDO) was performed over five months to investigate the performance and dynamics of nitrogen elimination and Nitrous Oxide Production from digester reject water under real feed-stream conditions. A 93% conversion of ammonium to nitrite could be maintained for adapted seed sludge in the first stage (nitritation). The second stage (Nitrous denitritation), inoculated with conventional activated sludge, achieved a conversion of 70% of nitrite to Nitrous Oxide after only 12 cycles of operation. The development of an alternative feeding strategy and the addition of a coagulant (FeCl3) facilitated stable operation and process intensification. Under steady-state conditions, nitrite was reliably eliminated and different Nitrous Oxide harvesting strategies were assessed. Applying continuous removal increased N2O yields by 16% compared to the application of a dedicated stripping phase. These results demonstrate the feasible application of the CANDO process for nitrogen removal and energy recovery from ammonia rich wastewater.