The Experts below are selected from a list of 8397 Experts worldwide ranked by ideXlab platform
Anna Schnürer - One of the best experts on this subject based on the ideXlab platform.
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trace element and temperature effects on microbial communities and links to Biogas Digester performance at high ammonia levels
Biotechnology for Biofuels, 2015Co-Authors: Maria Westerholm, Bettina Muller, Simon Isaksson, Anna SchnürerAbstract:High levels of ammonia and the presence of sulphide have major impacts on microbial communities and are known to cause operating problems in anaerobic degradation of protein-rich material. Operating strategies that can improve process performance in such conditions have been reported. The microbiological impacts of these are not fully understood, but their determination could help identify important factors for balanced, efficient operation. This study investigated the correlations between microbial community structure, operating parameters and Digester performance in high-ammonia conditions. Continuous anaerobic co-digestion of household waste and albumin was carried out in laboratory-scale Digesters at high ammonia concentrations (0.5–0.9 g NH3/L). The Digesters operated for 320 days at 37 or 42 °C, with or without addition of a trace element mixture including iron (TE). Abundance and composition of syntrophic acetate-oxidising bacteria (SAOB) and of methanogenic and acetogenic communities were investigated throughout the study using 16S rRNA and functional gene-based molecular methods. Syntrophic acetate oxidation dominated methane formation in all Digesters, where a substantial enhancement in Digester performance and influence on microbial community by addition of TE was shown dependent on temperature. At 37 °C, TE addition supported dominance and strain richness of Methanoculleus bourgensis and altered the acetogenic community, whereas the same supplementation at 42 °C had a low impact on microbial community structure. Both with and without TE addition operation at 42 °C instead of 37 °C had low impact on Digester performance, but considerably restricted acetogenic and methanogenic community structure, evenness and richness. The abundance of known SAOB was higher in Digesters without TE addition and in Digesters operating at 42 °C. No synergistic effect on Digester performance or microbial community structure was observed on combining increased temperature with TE addition. Our identification of prominent populations related to enhanced performance within methanogenic (high dominance and richness of M. bourgensis) and acetogenic communities are valuable for continued research and engineering to improve methane production in high-ammonia conditions. We also show that a temperature increase of only 5 °C within the mesophilic range results in an extreme dominance of one or a few species within these communities, independent of TE addition. Furthermore, functional stable operation was possible despite low microbial temporal dynamics, evenness and richness at the higher temperature.
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trace element and temperature effects on microbial communities and links to Biogas Digester performance at high ammonia levels
Biotechnology for Biofuels, 2015Co-Authors: Maria Westerholm, Bettina Muller, Simon Isaksson, Anna SchnürerAbstract:High levels of ammonia and the presence of sulphide have major impacts on microbial communities and are known to cause operating problems in anaerobic degradation of protein-rich material. Operating strategies that can improve process performance in such conditions have been reported. The microbiological impacts of these are not fully understood, but their determination could help identify important factors for balanced, efficient operation. This study investigated the correlations between microbial community structure, operating parameters and Digester performance in high-ammonia conditions. Continuous anaerobic co-digestion of household waste and albumin was carried out in laboratory-scale Digesters at high ammonia concentrations (0.5–0.9 g NH3/L). The Digesters operated for 320 days at 37 or 42 °C, with or without addition of a trace element mixture including iron (TE). Abundance and composition of syntrophic acetate-oxidising bacteria (SAOB) and of methanogenic and acetogenic communities were investigated throughout the study using 16S rRNA and functional gene-based molecular methods. Syntrophic acetate oxidation dominated methane formation in all Digesters, where a substantial enhancement in Digester performance and influence on microbial community by addition of TE was shown dependent on temperature. At 37 °C, TE addition supported dominance and strain richness of Methanoculleus bourgensis and altered the acetogenic community, whereas the same supplementation at 42 °C had a low impact on microbial community structure. Both with and without TE addition operation at 42 °C instead of 37 °C had low impact on Digester performance, but considerably restricted acetogenic and methanogenic community structure, evenness and richness. The abundance of known SAOB was higher in Digesters without TE addition and in Digesters operating at 42 °C. No synergistic effect on Digester performance or microbial community structure was observed on combining increased temperature with TE addition. Our identification of prominent populations related to enhanced performance within methanogenic (high dominance and richness of M. bourgensis) and acetogenic communities are valuable for continued research and engineering to improve methane production in high-ammonia conditions. We also show that a temperature increase of only 5 °C within the mesophilic range results in an extreme dominance of one or a few species within these communities, independent of TE addition. Furthermore, functional stable operation was possible despite low microbial temporal dynamics, evenness and richness at the higher temperature.
Surindra Suthar - One of the best experts on this subject based on the ideXlab platform.
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potential of domestic Biogas Digester slurry in vermitechnology
Bioresource Technology, 2010Co-Authors: Surindra SutharAbstract:This work illustrates the potential of domestic Biogas Digester slurry in vermicompost production. To achieve the objectives Biogas plant slurry (BGS) was mixed with crop residues (CR) in different ratios to produce seven different feed mixtures for earthworm Eisenia fetida. After 15 weeks vermicomposted material was analyzed for different chemical parameters. In all waste mixtures, a decrease in pH, organic C and C:N ratio, but increase total N, available P and exchangeable K was recorded. C:N ratio of end material (vermicompost) was within the agronomic acceptable limit (<20). The reproduction biology of E. fetida in different waste mixture was also monitored and they showed excellent biomass gain as well as cocoon production in all waste mixtures. The results clearly suggested that vermitechnology could be a potential technology to convert byproducts of domestic Biogas plant slurry into some value-added products.
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Potential of domestic Biogas Digester slurry in vermitechnology
Bioresource Technology, 2010Co-Authors: Surindra SutharAbstract:This work illustrates the potential of domestic Biogas Digester slurry in vermicompost production. To achieve the objectives Biogas plant slurry (BGS) was mixed with crop residues (CR) in different ratios to produce seven different feed mixtures for earthworm Eisenia fetida. After 15 weeks vermicomposted material was analyzed for different chemical parameters. In all waste mixtures, a decrease in pH, organic C and C:N ratio, but increase total N, available P and exchangeable K was recorded. C:N ratio of end material (vermicompost) was within the agronomic acceptable limit (
Dietmar Ramhold - One of the best experts on this subject based on the ideXlab platform.
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effect of ethylenediaminetetraacetic acid edta on the bioavailability of trace elements during anaerobic digestion
Chemical Engineering Journal, 2013Co-Authors: Anca Vintiloiu, Maike Boxriker, Andreas Lemmer, Hans Oechsner, Thomas Jungbluth, Edmund Mathies, Dietmar RamholdAbstract:Abstract The uptake of essential trace elements by methanogenic bacteria can be obstructed by precipitation in the presence of sulfides and carbonates. The objective of this study was to investigate whether the bioavailability of trace elements, and therefore the methane yield, can be improved through the use of complexing agents. Research showed that the use of EDTA as a complexing agent in the Biogas process increases the solubility of essential metals and enhances their bioavailability. If the substrate of a Biogas Digester has a low content of trace elements, solutions of elements essential for the methanogenic bacteria have to be added to the process. If these metals are complexed with EDTA prior to their supply, the necessary amount can be reduced by up to 75% compared to the non-complexed metals. Therefore, it would be advantageous for environmental and economic reasons to complex trace elements prior to their addition to the Biogas process.
Patrick Dabert - One of the best experts on this subject based on the ideXlab platform.
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feasibility and interest of the anammox process as treatment alternative for anaerobic Digester supernatants in manure processing an overview
Journal of Environmental Management, 2013Co-Authors: Albert Magri, Fabrice Béline, Patrick DabertAbstract:Abstract Completely autotrophic nitrogen removal (ANR) is based on the combination of partial nitritation (PN) and anaerobic ammonium oxidation (anammox). It is a promising alternative for the subsequent treatment of Biogas Digester supernatants in livestock manure processing and nitrogen surplus scenarios. However, as no full-scale experiences in the treatment of manure digestates by ANR have been published to date, future field studies addressing treatment of this kind of effluent would be of great interest. Some topics to be considered in these studies would be coupling anaerobic digestion and ANR, analysis of the factors that affect the process, comparing reactor configurations, microbial ecology, gas emissions, and achieving robust performance. This paper provides an overview of published studies on ANR. Specific issues related to the applicability of the process for treating manure digestates are discussed. The energy requirements of ANR are compared with those of other technological alternatives aimed at recovering nitrogen from Digester supernatants. The results of the assessment were shown to depend on the composition of the supernatant. In this regard, the PN-anammox process was shown to be more competitive than other alternatives particularly at concentrations of up to 2 kg NH 4 + –N m −3 .
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Feasibility and interest of the anammox process as treatment alternative for anaerobic Digester supernatants in manure processing – An overview
Journal of Environmental Management, 2013Co-Authors: Albert Magri, Fabrice Béline, Patrick DabertAbstract:Completely autotrophic nitrogen removal (ANR) is based on the combination of partial nitritation (PN) and anaerobic ammonium oxidation (anammox). It is a promising alternative for the subsequent treatment of Biogas Digester supernatants in livestock manure processing and nitrogen surplus scenarios. However, as no full-scale experiences in the treatment of manure digestates by ANR have been published to date, future field studies addressing treatment of this kind of effluent would be of great interest. Some topics to be considered in these studies would be coupling anaerobic digestion and ANR, analysis of the factors that affect the process, comparing reactor configurations, microbial ecology, gas emissions, and achieving robust performance. This paper provides an overview of published studies on ANR. Specific issues related to the applicability of the process for treating manure digestates are discussed. The energy requirements of ANR are compared with those of other technological alternatives aimed at recovering nitrogen from Digester supernatants. The results of the assessment were shown to depend on the composition of the supernatant. In this regard, the PN-anammox process was shown to be more competitive than other alternatives particularly at concentrations of up to 2 kg NH4+–N m−3.
Maria Westerholm - One of the best experts on this subject based on the ideXlab platform.
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trace element and temperature effects on microbial communities and links to Biogas Digester performance at high ammonia levels
Biotechnology for Biofuels, 2015Co-Authors: Maria Westerholm, Bettina Muller, Simon Isaksson, Anna SchnürerAbstract:High levels of ammonia and the presence of sulphide have major impacts on microbial communities and are known to cause operating problems in anaerobic degradation of protein-rich material. Operating strategies that can improve process performance in such conditions have been reported. The microbiological impacts of these are not fully understood, but their determination could help identify important factors for balanced, efficient operation. This study investigated the correlations between microbial community structure, operating parameters and Digester performance in high-ammonia conditions. Continuous anaerobic co-digestion of household waste and albumin was carried out in laboratory-scale Digesters at high ammonia concentrations (0.5–0.9 g NH3/L). The Digesters operated for 320 days at 37 or 42 °C, with or without addition of a trace element mixture including iron (TE). Abundance and composition of syntrophic acetate-oxidising bacteria (SAOB) and of methanogenic and acetogenic communities were investigated throughout the study using 16S rRNA and functional gene-based molecular methods. Syntrophic acetate oxidation dominated methane formation in all Digesters, where a substantial enhancement in Digester performance and influence on microbial community by addition of TE was shown dependent on temperature. At 37 °C, TE addition supported dominance and strain richness of Methanoculleus bourgensis and altered the acetogenic community, whereas the same supplementation at 42 °C had a low impact on microbial community structure. Both with and without TE addition operation at 42 °C instead of 37 °C had low impact on Digester performance, but considerably restricted acetogenic and methanogenic community structure, evenness and richness. The abundance of known SAOB was higher in Digesters without TE addition and in Digesters operating at 42 °C. No synergistic effect on Digester performance or microbial community structure was observed on combining increased temperature with TE addition. Our identification of prominent populations related to enhanced performance within methanogenic (high dominance and richness of M. bourgensis) and acetogenic communities are valuable for continued research and engineering to improve methane production in high-ammonia conditions. We also show that a temperature increase of only 5 °C within the mesophilic range results in an extreme dominance of one or a few species within these communities, independent of TE addition. Furthermore, functional stable operation was possible despite low microbial temporal dynamics, evenness and richness at the higher temperature.
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trace element and temperature effects on microbial communities and links to Biogas Digester performance at high ammonia levels
Biotechnology for Biofuels, 2015Co-Authors: Maria Westerholm, Bettina Muller, Simon Isaksson, Anna SchnürerAbstract:High levels of ammonia and the presence of sulphide have major impacts on microbial communities and are known to cause operating problems in anaerobic degradation of protein-rich material. Operating strategies that can improve process performance in such conditions have been reported. The microbiological impacts of these are not fully understood, but their determination could help identify important factors for balanced, efficient operation. This study investigated the correlations between microbial community structure, operating parameters and Digester performance in high-ammonia conditions. Continuous anaerobic co-digestion of household waste and albumin was carried out in laboratory-scale Digesters at high ammonia concentrations (0.5–0.9 g NH3/L). The Digesters operated for 320 days at 37 or 42 °C, with or without addition of a trace element mixture including iron (TE). Abundance and composition of syntrophic acetate-oxidising bacteria (SAOB) and of methanogenic and acetogenic communities were investigated throughout the study using 16S rRNA and functional gene-based molecular methods. Syntrophic acetate oxidation dominated methane formation in all Digesters, where a substantial enhancement in Digester performance and influence on microbial community by addition of TE was shown dependent on temperature. At 37 °C, TE addition supported dominance and strain richness of Methanoculleus bourgensis and altered the acetogenic community, whereas the same supplementation at 42 °C had a low impact on microbial community structure. Both with and without TE addition operation at 42 °C instead of 37 °C had low impact on Digester performance, but considerably restricted acetogenic and methanogenic community structure, evenness and richness. The abundance of known SAOB was higher in Digesters without TE addition and in Digesters operating at 42 °C. No synergistic effect on Digester performance or microbial community structure was observed on combining increased temperature with TE addition. Our identification of prominent populations related to enhanced performance within methanogenic (high dominance and richness of M. bourgensis) and acetogenic communities are valuable for continued research and engineering to improve methane production in high-ammonia conditions. We also show that a temperature increase of only 5 °C within the mesophilic range results in an extreme dominance of one or a few species within these communities, independent of TE addition. Furthermore, functional stable operation was possible despite low microbial temporal dynamics, evenness and richness at the higher temperature.