The Experts below are selected from a list of 1500 Experts worldwide ranked by ideXlab platform
Michalis Koutinas - One of the best experts on this subject based on the ideXlab platform.
-
Actinobacillus succinogenes: Advances on succinic acid production and prospects for development of Integrated Biorefineries
Biochemical Engineering Journal, 2016Co-Authors: Chrysanthi Pateraki, Maria Patsalou, Nikolaos Kopsahelis, Anestis Vlysidis, Athanasios A. Koutinas, Michalis KoutinasAbstract:Actinobacillus succinogenes is a wild-type bacterial strain, isolated from bovine rumen, known as one of the most efficient natural producers of succinic acid. Herein, the factors contributing to the fermentative production of succinic acid by A. succinogenes are reviewed with particular focus on raw materials, culture conditions, significance of carbon dioxide availability and downstream separation and purification. The metabolic potential of this strain is evaluated through discussion of the pathways involved in succinic acid production, genome analysis as well as the development of A. succinogenes mutants. The review also addresses the importance of by-product formation during fermentation that constitutes an important aspect regulating succinic acid production by A. succinogenes. The prospect of integrating succinic acid production in future Biorefineries is assessed.
Athanasios A. Koutinas - One of the best experts on this subject based on the ideXlab platform.
-
Actinobacillus succinogenes: Advances on succinic acid production and prospects for development of Integrated Biorefineries
Biochemical Engineering Journal, 2016Co-Authors: Chrysanthi Pateraki, Maria Patsalou, Nikolaos Kopsahelis, Anestis Vlysidis, Athanasios A. Koutinas, Michalis KoutinasAbstract:Actinobacillus succinogenes is a wild-type bacterial strain, isolated from bovine rumen, known as one of the most efficient natural producers of succinic acid. Herein, the factors contributing to the fermentative production of succinic acid by A. succinogenes are reviewed with particular focus on raw materials, culture conditions, significance of carbon dioxide availability and downstream separation and purification. The metabolic potential of this strain is evaluated through discussion of the pathways involved in succinic acid production, genome analysis as well as the development of A. succinogenes mutants. The review also addresses the importance of by-product formation during fermentation that constitutes an important aspect regulating succinic acid production by A. succinogenes. The prospect of integrating succinic acid production in future Biorefineries is assessed.
-
design and techno economic evaluation of microbial oil production as a renewable resource for biodiesel and oleochemical production
Fuel, 2014Co-Authors: Athanasios A. Koutinas, Afroditi Chatzifragkou, Seraphim Papanikolaou, Nikolaos Kopsahelis, Ioannis K KookosAbstract:Abstract Experimental results from the open literature have been employed for the design and techno-economic evaluation of four process flowsheets for the production of microbial oil or biodiesel. The fermentation of glucose-based media using the yeast strain Rhodosporidium toruloides has been considered. Biodiesel production was based on the exploitation of either direct transesterification (without extraction of lipids from microbial biomass) or indirect transesterifaction of extracted microbial oil. When glucose-based renewable resources are used as carbon source for an annual production capacity of 10,000 t microbial oil and zero cost of glucose (assuming development of Integrated Biorefineries in existing industries utilising waste or by-product streams) the estimated unitary cost of purified microbial oil is $3.4/kg. Biodiesel production via indirect transesterification of extracted microbial oil proved more cost-competitive process compared to the direct conversion of dried yeast cells. For a price of glucose of $400/t oil production cost and biodiesel production cost are estimated to be $5.5/kg oil and $5.9/kg biodiesel, correspondingly. Industrial implementation of microbial oil production from oleaginous yeast is strongly dependent on the feedstock used and on the fermentation stage where significantly higher productivities and final microbial oil concentrations should be achieved.
Adisa Azapagic - One of the best experts on this subject based on the ideXlab platform.
-
life cycle environmental sustainability of lignocellulosic ethanol produced in Integrated thermo chemical Biorefineries
Biofuels Bioproducts and Biorefining, 2015Co-Authors: Harish Kumar Jeswani, Temitope Falano, Adisa AzapagicAbstract:There is a growing interest in producing biofuels and bio-chemicals from lignocellulosic feedstocks in Integrated Biorefineries. However, the sustainability implications of Integrated Biorefineries are still poorly understood. Using a life cycle approach, this paper examines environmental impacts of second-generation ethanol produced in thermo-chemical refineries together with chemicals and energy. Four feedstocks are considered: wheat straw, poplar, Miscanthus and forest residue. The results suggest that the production of ethanol from these feedstocks offers significant savings in eight out of 12 environmental impacts when the system is credited for the avoided impacts from producing the co-products from fossil resources. Ethanol from forest residue is the best and wheat straw the worst option for most impacts. Land use change has a significant effect on the global warming potential (GWP) of ethanol. For example, conversion of forest to grow Miscanthus increases the GWP from –234 to 6685 g CO2 eq./l of ethanol. The effect is opposite when grassland is converted to grow poplar: the GWP is reduced by two times because of carbon sequestration by poplar. The thermo-chemical route for producing ethanol from poplar and forest residue is more sustainable for most impacts than the bio-chemical conversion with the same feedstocks. Although ethanol saves up to 83% of GHG emissions per MJ of fuel compared to petrol, the savings are much smaller (~3%) for current ethanol blends of 5%. Therefore, unless a much higher proportion of ethanol was used, the contribution of second-generation ethanol to climate change mitigation would be small. © 2015 The Authors. Biofuels, Bioproducts, Biorefining published by Society of Chemical Industry and John Wiley & Sons, Ltd.
-
assessing the environmental sustainability of ethanol from Integrated Biorefineries
Biotechnology Journal, 2014Co-Authors: Temitope Falano, Harish Kumar Jeswani, Adisa AzapagicAbstract:This paper considers the life cycle environmental sustainability of ethanol produced in Integrated Biorefineries together with chemicals and energy. Four types of second-generation feedstocks are considered: wheat straw, forest residue, poplar, and miscanthus. Seven out of 11 environmental impacts from ethanol are negative, including greenhouse gas (GHG) emissions, when the system is credited for the co-products, indicating environmental savings. Ethanol from poplar is the best and straw the worst option for most impacts. Land use change from forest to miscanthus increases the GHG emissions several-fold. For poplar, the effect is opposite: converting grassland to forest reduces the emissions by three-fold. Compared to fossil and first-generation ethanol, ethanol from Integrated Biorefineries is more sustainable for most impacts, with the exception of wheat straw. Pure ethanol saves up to 87% of GHG emissions compared to petrol per MJ of fuel. However, for the current 5% ethanol–petrol blends, the savings are much smaller (<3%). Therefore, unless much higher blends become widespread, the contribution of ethanol from Integrated Biorefineries to the reduction of GHG emissions will be insignificant. Yet, higher ethanol blends would lead to an increase in some impacts, notably terrestrial and freshwater toxicity as well as eutrophication for some feedstocks.
-
sustainability considerations for Integrated Biorefineries
Trends in Biotechnology, 2014Co-Authors: Adisa AzapagicAbstract:Integrated Biorefineries have the potential to contribute towards sustainable production of transportation fuels, energy, and chemicals. However, because there are currently no commercial biorefining plants in operation, it is not clear how sustainable they really are. This paper sets out to examine key issues associated with biorefining that should be considered carefully along the whole supply chain to ensure sustainable development of the sector.
-
life cycle sustainability assessment of second generation biodiesel
In: R. Luque and J. A. Melero editor(s). Advances in Biodiesel Preparation - Second Generation Processes and Technologies. London: Woodhead Publishers, 2012Co-Authors: Harish Kumar Jeswani, Adisa AzapagicAbstract:Abstract: Second generation biodiesel could contribute to significant reductions in carbon dioxide emissions from transport because the biofeedstock used for their production is considered to be carbon neutral. This chapter examines the life cycle sustainability of second generation biodiesel derived from different feedstocks and produced in different production systems, including Integrated Biorefineries. The environmental sustainability aspects considered include water use, global warming, acidification, eutrophication and loss of biodiversity. The socio-economic impacts are also reviewed, including feedstock and capital costs, value added through production of by-products as well as the social acceptability of biofuels. The future viability of biodiesel is also discussed.
Nikolaos Kopsahelis - One of the best experts on this subject based on the ideXlab platform.
-
Actinobacillus succinogenes: Advances on succinic acid production and prospects for development of Integrated Biorefineries
Biochemical Engineering Journal, 2016Co-Authors: Chrysanthi Pateraki, Maria Patsalou, Nikolaos Kopsahelis, Anestis Vlysidis, Athanasios A. Koutinas, Michalis KoutinasAbstract:Actinobacillus succinogenes is a wild-type bacterial strain, isolated from bovine rumen, known as one of the most efficient natural producers of succinic acid. Herein, the factors contributing to the fermentative production of succinic acid by A. succinogenes are reviewed with particular focus on raw materials, culture conditions, significance of carbon dioxide availability and downstream separation and purification. The metabolic potential of this strain is evaluated through discussion of the pathways involved in succinic acid production, genome analysis as well as the development of A. succinogenes mutants. The review also addresses the importance of by-product formation during fermentation that constitutes an important aspect regulating succinic acid production by A. succinogenes. The prospect of integrating succinic acid production in future Biorefineries is assessed.
-
design and techno economic evaluation of microbial oil production as a renewable resource for biodiesel and oleochemical production
Fuel, 2014Co-Authors: Athanasios A. Koutinas, Afroditi Chatzifragkou, Seraphim Papanikolaou, Nikolaos Kopsahelis, Ioannis K KookosAbstract:Abstract Experimental results from the open literature have been employed for the design and techno-economic evaluation of four process flowsheets for the production of microbial oil or biodiesel. The fermentation of glucose-based media using the yeast strain Rhodosporidium toruloides has been considered. Biodiesel production was based on the exploitation of either direct transesterification (without extraction of lipids from microbial biomass) or indirect transesterifaction of extracted microbial oil. When glucose-based renewable resources are used as carbon source for an annual production capacity of 10,000 t microbial oil and zero cost of glucose (assuming development of Integrated Biorefineries in existing industries utilising waste or by-product streams) the estimated unitary cost of purified microbial oil is $3.4/kg. Biodiesel production via indirect transesterification of extracted microbial oil proved more cost-competitive process compared to the direct conversion of dried yeast cells. For a price of glucose of $400/t oil production cost and biodiesel production cost are estimated to be $5.5/kg oil and $5.9/kg biodiesel, correspondingly. Industrial implementation of microbial oil production from oleaginous yeast is strongly dependent on the feedstock used and on the fermentation stage where significantly higher productivities and final microbial oil concentrations should be achieved.
Esbjorn Pettersson - One of the best experts on this subject based on the ideXlab platform.
-
mixing of fast pyrolysis oil and black liquor preparing an improved gasification feedstock
Energy & Fuels, 2016Co-Authors: Erik Furusjo, Esbjorn PetterssonAbstract:Co-gasification of fast pyrolysis oil and black liquor can be used to increase the size and improve profitability of pulp mill Integrated Biorefineries. The acids present in pyrolysis oil limit the amount that can be mixed into black liquor without causing precipitation of the black liquor dissolved lignin. This work shows that a simple model based on pyrolysis oil total acid number, including weak phenolic acids, can be used to predict the maximum pyrolysis oil fraction in blends. The maximum oil fraction is 20–25% for typical pyrolysis oil but can be increased up to at least 50% mass, corresponding to 70% energy, by addition of base. Thermodynamic equilibrium calculations are used to understand the effects of blend composition, including any added base, on the performance of a commercial scale gasification process. A substantial increase in overall gasification efficiency is observed with increasing pyrolysis oil fraction.