| 1. |
- Alvfors, Per, 1954-, et al.
(författare)
-
Research and development challenges for Swedish biofuel actors – three illustrative examples : Improvement potential discussed in the context of Well-to-Tank analyses
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Currently biofuels have strong political support, both in the EU and Sweden. The EU has, for example, set a target for the use of renewable fuels in the transportation sector stating that all EU member states should use 10% renewable fuels for transport by 2020. Fulfilling this ambition will lead to an enormous market for biofuels during the coming decade. To avoid increasing production of biofuels based on agriculture crops that require considerable use of arable area, focus is now to move towards more advanced second generation (2G) biofuels that can be produced from biomass feedstocks associated with a more efficient land use. Climate benefits and greenhouse gas (GHG) balances are aspects often discussed in conjunction with sustainability and biofuels. The total GHG emissions associated with production and usage of biofuels depend on the entire fuel production chain, mainly the agriculture or forestry feedstock systems and the manufacturing process. To compare different biofuel production pathways it is essential to conduct an environmental assessment using the well-to-tank (WTT) analysis methodology. In Sweden the conditions for biomass production are favourable and we have promising second generation biofuels technologies that are currently in the demonstration phase. In this study we have chosen to focus on cellulose based ethanol, methane from gasification of solid wood as well as DME from gasification of black liquor, with the purpose of identifying research and development potentials that may result in improvements in the WTT emission values. The main objective of this study is thus to identify research and development challenges for Swedish biofuel actors based on literature studies as well as discussions with the the researchers themselves. We have also discussed improvement potentials for the agriculture and forestry part of the WTT chain. The aim of this study is to, in the context of WTT analyses, (i) increase knowledge about the complexity of biofuel production, (ii) identify and discuss improvement potentials, regarding energy efficiency and GHG emissions, for three biofuel production cases, as well as (iii) identify and discuss improvement potentials regarding biomass supply, including agriculture/forestry. The scope of the study is limited to discussing the technologies, system aspects and climate impacts associated with the production stage. Aspects such as the influence on biodiversity and other environmental and social parameters fall beyond the scope of this study. We find that improvement potentials for emissions reductions within the agriculture/forestry part of the WTT chain include changing the use of diesel to low-CO2-emitting fuels, changing to more fuel-efficient tractors, more efficient cultivation and manufacture of fertilizers (commercial nitrogen fertilizer can be produced in plants which have nitrous oxide gas cleaning) as well as improved fertilization strategies (more precise nitrogen application during the cropping season). Furthermore, the cultivation of annual feedstock crops could be avoided on land rich in carbon, such as peat soils and new agriculture systems could be introduced that lower the demand for ploughing and harrowing. Other options for improving the WTT emission values includes introducing new types of crops, such as wheat with higher content of starch or willow with a higher content of cellulose. From the case study on lignocellulosic ethanol we find that 2G ethanol, with co-production of biogas, electricity, heat and/or wood pellet, has a promising role to play in the development of sustainable biofuel production systems. Depending on available raw materials, heat sinks, demand for biogas as vehicle fuel and existing 1G ethanol plants suitable for integration, 2G ethanol production systems may be designed differently to optimize the economic conditions and maximize profitability. However, the complexity connected to the development of the most optimal production systems require improved knowledge and involvement of several actors from different competence areas, such as chemical and biochemical engineering, process design and integration and energy and environmental systems analysis, which may be a potential barrier.
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| 2. |
- Alvfors, Per, et al.
(författare)
-
Research and development challenges for Swedish biofuel actors – three illustrative examples
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Currently biofuels have strong political support, both in the EU and Sweden. The EU has, for example, set a target for the use of renewable fuels in the transportation sector stating that all EU member states should use 10% renewable fuels for transport by 2020. Fulfilling this ambition will lead to an enormous market for biofuels during the coming decade. To avoid increasing production of biofuels based on agriculture crops that require considerable use of arable area, focus is now to move towards more advanced second generation (2G) biofuels that can be produced from biomass feedstocks associated with a more efficient land use.Climate benefits and greenhouse gas (GHG) balances are aspects often discussed in conjunction with sustainability and biofuels. The total GHG emissions associated with production and usage of biofuels depend on the entire fuel production chain, mainly the agriculture or forestry feedstock systems and the manufacturing process. To compare different biofuel production pathways it is essential to conduct an environmental assessment using the well-to-tank (WTT) analysis methodology. In Sweden the conditions for biomass production are favourable and we have promising second generation biofuels technologies that are currently in the demonstration phase. In this study we have chosen to focus on cellulose based ethanol, methane from gasification of solid wood as well as DME from gasification of black liquor, with the purpose of identifying research and development potentials that may result in improvements in the WTT emission values. The main objective of this study is thus to identify research and development challenges for Swedish biofuel actors based on literature studies as well as discussions with the the researchers themselves. We have also discussed improvement potentials for the agriculture and forestry part of the WTT chain. The aim of this study is to, in the context of WTT analyses, (i) increase knowledge about the complexity of biofuel production, (ii) identify and discuss improvement potentials, regarding energy efficiency and GHG emissions, for three biofuel production cases, as well as (iii) identify and discuss improvement potentials regarding biomass supply, including agriculture/forestry. The scope of the study is limited to discussing the technologies, system aspects and climate impacts associated with the production stage. Aspects such as the influence on biodiversity and other environmental and social parameters fall beyond the scope of this study. We find that improvement potentials for emissions reductions within the agriculture/forestry part of the WTT chain include changing the use of diesel to low-CO2-emitting fuels, changing to more fuel-efficient tractors, more efficient cultivation and manufacture of fertilizers (commercial nitrogen fertilizer can be produced in plants which have nitrous oxide gas cleaning) as well as improved fertilization strategies (more precise nitrogen application during the cropping season). Furthermore, the cultivation of annual feedstock crops could be avoided on land rich in carbon, such as peat soils and new agriculture systems could be introduced that lower the demand for ploughing and harrowing. Other options for improving the WTT emission values includes introducing new types of crops, such as wheat with higher content of starch or willow with a higher content of cellulose. From the case study on lignocellulosic ethanol we find that 2G ethanol, with co-production of biogas, electricity, heat and/or wood pellet, has a promising role to play in the development of sustainable biofuel production systems. Depending on available raw materials, heat sinks, demand for biogas as vehicle fuel and existing 1G ethanol plants suitable for integration, 2G ethanol production systems may be designed differently to optimize the economic conditions and maximize profitability. However, the complexity connected to the development of the most optimal production systems require improved knowledge and involvement of several actors from different competence areas, such as chemical and biochemical engineering, process design and integration and energy and environmental systems analysis, which may be a potential barrier. Three important results from the lignocellulosic ethanol study are: (i) the production systems could be far more complex and intelligently designed than previous studies show, (ii) the potential improvements consist of a large number of combinations of process integration options wich partly depends on specific local conditions, (iii) the environmental performance of individual systems may vary significantly due to systems design and local conditons.From the case study on gasification of solid biomass for the production of biomethane we find that one of the main advantages of this technology is its high efficiency in respect to converting biomass into fuels for transport. For future research we see a need for improvements within the gas up-grading section, including gas cleaning and gas conditioning, to obtain a more efficient process. A major challenge is to remove the tar before the methanation reaction. Three important results from the biomethane study are: (i) it is important not to crack the methane already produced in the syngas, which indicates a need for improved catalysts for selective tar cracking, (ii) there is a need for new gas separation techniques to facilitate the use of air oxidation agent instead of oxygen in the gasifier, and (iii) there is a need for testing the integrated process under realistic conditions, both at atmospheric and pressurized conditions. From the case study on black liquor gasification for the production of DME we find that the process has many advantages compared to other biofuel production options, such as the fact that black liquor is already partially processed and exists in a pumpable, liquid form, and that the process is pressurised and tightly integrated with the pulp mill, which enhances fuel production efficiency. However, to achieve commercial status, some challenges still remain, such as demonstrating that materials and plant equipment meet the high availability required when scaling up to industrial size in the pulp mill, and also proving that the plant can operate according to calculated heat and material balances. Three important results from the DME study are: (i) that modern chemical pulp mills, having a potential surplus of energy, could become important suppliers of renewable fuels for transport, (ii) there is a need to demonstrate that renewable DME/methanol will be proven to function in large scale, and (iii) there is still potential for technology improvements and enhanced energy integration. Although quantitative improvement potentials are given in the three biofuel production cases, it is not obvious how these potentials would affect WTT values, since the biofuel production processes are complex and changing one parameter impacts other parameters. The improvement potentials are therefore discussed qualitatively. From the entire study we have come to agree on the following common conclusions: (i) research and development in Sweden within the three studied 2G biofuel production technologies is extensive, (ii) in general, the processes, within the three cases, work well at pilot and demonstration scale and are now in a phase to be proven in large scale, (iii) there is still room for improvement although some processes have been known for decades, (iv) the biofuel production processes are complex and site specific and process improvements need to be seen and judged from a broad systems perspective (both within the production plant as well as in the entire well-to-tank perspective), and (v) the three studied biofuel production systems are complementary technologies. Futher, the process of conducting this study is worth mentioning as a result itself, i.e. that many different actors within the field have proven their ability and willingness to contribute to a common report, and that the cooperation climate was very positive and bodes well for possible future collaboration within the framework of the f3 center. Finally, judging from the political ambitions it is clear that the demand for renewable fuels will significantly increase during the coming decade. This will most likely result in opportunities for a range of biofuel options. The studied biofuel options all represent 2G biofuels and they can all be part of the solution to meet the increased renewable fuel demand.
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| 3. |
- Alvors, Per, et al.
(författare)
-
Research and development challenges for Swedish biofuel actors – three illustrative examples : Improvement potential discussed in the context of Well-to-Tank analyses
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Currently biofuels have strong political support, both in the EU and Sweden. The EU has, for example, set a target for the use of renewable fuels in the transportation sector stating that all EU member states should use 10% renewable fuels for transport by 2020. Fulfilling this ambition will lead to an enormous market for biofuels during the coming decade. To avoid increasing production of biofuels based on agriculture crops that require considerable use of arable area, focus is now to move towards more advanced second generation (2G) biofuels that can be produced from biomass feedstocks associated with a more efficient land use.Climate benefits and greenhouse gas (GHG) balances are aspects often discussed in conjunction with sustainability and biofuels. The total GHG emissions associated with production and usage of biofuels depend on the entire fuel production chain, mainly the agriculture or forestry feedstock systems and the manufacturing process. To compare different biofuel production pathways it is essential to conduct an environmental assessment using the well-to-tank (WTT) analysis methodology.In Sweden the conditions for biomass production are favourable and we have promising second generation biofuels technologies that are currently in the demonstration phase. In this study we have chosen to focus on cellulose based ethanol, methane from gasification of solid wood as well as DME from gasification of black liquor, with the purpose of identifying research and development potentials that may result in improvements in the WTT emission values. The main objective of this study is thus to identify research and development challenges for Swedish biofuel actors based on literature studies as well as discussions with the the researchers themselves. We have also discussed improvement potentials for the agriculture and forestry part of the WTT chain. The aim of this study is to, in the context of WTT analyses, (i) increase knowledge about the complexity of biofuel production, (ii) identify and discuss improvement potentials, regarding energy efficiency and GHG emissions, for three biofuel production cases, as well as (iii) identify and discuss improvement potentials regarding biomass supply, including agriculture/forestry. The scope of the study is limited to discussing the technologies, system aspects and climate impacts associated with the production stage. Aspects such as the influence on biodiversity and other environmental and social parameters fall beyond the scope of this study.We find that improvement potentials for emissions reductions within the agriculture/forestry part of the WTT chain include changing the use of diesel to low-CO2-emitting fuels, changing to more fuel-efficient tractors, more efficient cultivation and manufacture of fertilizers (commercial nitrogen fertilizer can be produced in plants which have nitrous oxide gas cleaning) as well as improved fertilization strategies (more precise nitrogen application during the cropping season). Furthermore, the cultivation of annual feedstock crops could be avoided on land rich in carbon, such as peat soils and new agriculture systems could be introduced that lower the demand for ploughing and harrowing. Other options for improving the WTT emission values includes introducing new types of crops, such as wheat with higher content of starch or willow with a higher content of cellulose.From the case study on lignocellulosic ethanol we find that 2G ethanol, with co-production of biogas, electricity, heat and/or wood pellet, has a promising role to play in the development of sustainable biofuel production systems. Depending on available raw materials, heat sinks, demand for biogas as vehicle fuel and existing 1G ethanol plants suitable for integration, 2G ethanol production systems may be designed differently to optimize the economic conditions and maximize profitability. However, the complexity connected to the development of the most optimal production systems require improved knowledge and involvement of several actors from different competence areas, such as chemical and biochemical engineering, process design and integration and energy and environmental systems analysis, which may be a potential barrier.Three important results from the lignocellulosic ethanol study are: (i) the production systems could be far more complex and intelligently designed than previous studies show, (ii) the potential improvements consist of a large number of combinations of process integration options wich partly depends on specific local conditions, (iii) the environmental performance of individual systems may vary significantly due to systems design and local conditons.From the case study on gasification of solid biomass for the production of biomethane we find that one of the main advantages of this technology is its high efficiency in respect to converting biomass into fuels for transport. For future research we see a need for improvements within the gas up-grading section, including gas cleaning and gas conditioning, to obtain a more efficient process. A major challenge is to remove the tar before the methanation reaction.Three important results from the biomethane study are: (i) it is important not to crack the methane already produced in the syngas, which indicates a need for improved catalysts for selective tar cracking, (ii) there is a need for new gas separation techniques to facilitate the use of air oxidation agent instead of oxygen in the gasifier, and (iii) there is a need for testing the integrated process under realistic conditions, both at atmospheric and pressurized conditions.From the case study on black liquor gasification for the production of DME we find that the process has many advantages compared to other biofuel production options, such as the fact that black liquor is already partially processed and exists in a pumpable, liquid form, and that the process is pressurised and tightly integrated with the pulp mill, which enhances fuel production efficiency. However, to achieve commercial status, some challenges still remain, such as demonstrating that materials and plant equipment meet the high availability required when scaling up to industrial size in the pulp mill, and also proving that the plant can operate according to calculated heat and material balances. Three important results from the DME study are: (i) that modern chemical pulp mills, having a potential surplus of energy, could become important suppliers of renewable fuels for transport, (ii) there is a need to demonstrate that renewable DME/methanol will be proven to function in large scale, and (iii) there is still potential for technology improvements and enhanced energy integration.Although quantitative improvement potentials are given in the three biofuel production cases, it is not obvious how these potentials would affect WTT values, since the biofuel production processes are complex and changing one parameter impacts other parameters. The improvement potentials are therefore discussed qualitatively. From the entire study we have come to agree on the following common conclusions: (i) research and development in Sweden within the three studied 2G biofuel production technologies is extensive, (ii) in general, the processes, within the three cases, work well at pilot and demonstration scale and are now in a phase to be proven in large scale, (iii) there is still room for improvement although some processes have been known for decades, (iv) the biofuel production processes are complex and site specific and process improvements need to be seen and judged from a broad systems perspective (both within the production plant as well as in the entire well-to-tank perspective), and (v) the three studied biofuel production systems are complementary technologies. Futher, the process of conducting this study is worth mentioning as a result itself, i.e. that many different actors within the field have proven their ability and willingness to contribute to a common report, and that the cooperation climate was very positive and bodes well for possible future collaboration within the framework of the f3 center.Finally, judging from the political ambitions it is clear that the demand for renewable fuels will significantly increase during the coming decade. This will most likely result in opportunities for a range of biofuel options. The studied biofuel options all represent 2G biofuels and they can all be part of the solution to meet the increased renewable fuel demand.
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| 4. |
- Anheden, Marie, et al.
(författare)
-
Value chain for production of bio-oil from kraft lignin for use as bio-jet fuel
- 2017
-
Ingår i: The 7th Nordic Wood Biorefinery Conference held in Stockholm, Sweden, 28-30 Mar. 2017. - Stockholm : RISE Bioekonomi. - 9789186018207 ; , s. 104-109
-
Konferensbidrag (refereegranskat)abstract
- The LignoJet project aimed to achieve an intermediate lignin-oil product miscible with fossil feedstock and with a significantly reduced oxygen content. A technical concept for production has been studied that involves combined catalysed depolymerisation and hydrodeoxygenation, so called hydrogenolytic depolymerisation, of kraft lignin. Kraft lignin was separated through membrane ultrafiltration from softwood and eucalyptus black liquor followed by precipitation through LignoBoost technology. A difference in lignin properties was observed between ultrafiltration of softwood and eucalyptus black liquor through 15 and 150kDa ceramic membranes. Lignin-oils with similar oxygen content were produced regardless of origin and fractionation technique. A lignin-oil with favourable properties as precursor for refinery integration for jet fuel production as produced in small-scale batch experiments using nickel-based catalyst. Stable pumpable oils with melting point of less than 25-50 deg C and with 20-30% lower oxygen content and aromatic content were obtained that would be suitable as jet fuel precursors. The estimated production cost was found to be competitive with that of other liquid biofuels, while additional revenues could potentially be achieved by also producing chemical and materials from suitable fractions of the lignin-oil.
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| 5. |
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| 6. |
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| 7. |
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| 8. |
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| 9. |
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| 10. |
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| 11. |
- Berglin, Niklas, et al.
(författare)
-
Experiences from feeding and co-firing of lignin powder in a lime kiln
- 2010
-
Ingår i: International Chemical Recovery Conference. ; , s. 175-187
-
Konferensbidrag (refereegranskat)abstract
- A significant part of the fossil fuel oil consumption at a pulp mill today is related to combustion in the lime kiln. Therefore, replacing fuel oil with lignin in this application has been one of the most important issues in the FRAM2 (Future Resource-Adapted Mill) research program coordinated by Innventia (formerly STFl-Packforsk) and funded by Sodra and other partners. A full-scale trial to fire lignin powder in a lime kiln was carried out at the Sodra Cell Monsteras mill, as part of the research program. In total 37 tonnes of lignin was co-fired with fuel oil. For part of the trial the kiln was operated on 100 % lignin. The experiences from the trial imply that it is possible to achieve stable and continuous operation of a lime kiln when lignin is used as the main fuel. The temperature levels in the kiln are of the same order of magnitude as when firing fuel oil or wood powder. Sulfur capture by the lime is very efficient, but there is a threshold above which S02 emissions increase rapidly. In the trial this step change occurred when going from 90 % to 100 % lignin firing. Based on the trial results, it is possible to produce lime with consistent quality when firing lignin, and the temperature reached in the burner zone is sufficient for proper sintering of the lime nodules. White liquor can be produced from the lime with the same causticizing efficiency and at the same rate as during normal operation. The mill operators also commented that it was easier to control the performance of the kiln when co-firing lignin and oil compared to the normal operation with co-firing of bark and oil.
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| 12. |
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| 13. |
- Berglin, Niklas, et al.
(författare)
-
Pilot-scale combustion studies with kraft lignin as a solid biofuel
- 2008
-
Ingår i: Engineering, Pulping and Environmental Conference 2008. - : TAPPI Press. - 9781605605081 ; , s. 2571-2580
-
Konferensbidrag (refereegranskat)abstract
- Processing of kraft lignin precipitated from black liquor to produce a solid biofuel with high energy density and low ash content has been developed in research programs by STFI-Packforsk and partners. In preparation for full-scale combustion trials, tests were carried out on pilot scale in a 150 kW powder burner and in a 12 MWfluidized bed (CFB) boiler. Lignin powder could be fired in a powder burner with good combustion performance after some trimming of the airflows to reduce swirl. Lignin dried to 10 % moisture content was easy to feed smoothly and had less bridging tendencies in the feeding system than wood/bark powder. In the CFB boiler lignin was easily handled and co-fired together with bark. Although the filter cake was broken into smaller pieces and fines the combustion was not disturbed. When co-firing lignin with bark, the sulfur emission increased compared to bark firing only, but most of the sulfur was captured by calcium in the bark ash. Conventional sulfur capture with addition of limestone to the bed was also demonstrated. The sulfur content in the lignin had a significantly positive effect on reducing the alkali chloride content in the deposits, thus reducing the high temperature corrosion risk.
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| 14. |
- Berglin, Niklas, et al.
(författare)
-
Pilot-scale combustion studies with kraft lignin in a powder burner and a CFB boiler
- 2010
-
Ingår i: TAPPI Journal. - 0734-1415. ; 9:6, s. 24-30
-
Tidskriftsartikel (refereegranskat)abstract
- Processes have been developed to produce a solid biofuel with high energy density and low ash content from kraft lignin precipitated from black liquor. Pilot-scale tests of the lignin biofuel were carried out with a 150 kW powder burner and a 12 MW circulating fluidized bed (CFB) boiler. Lignin powder could be fired in a powder burner with good combustion performance after some trimming of the air flows to reduce swirl. Lignin dried to 10% moisture content was easy to feed smoothly and had less bridging tendencies in the feeding system than did wood/ bark powder. In the CFB boiler, lignin was easily handled and cofired together with bark. Although the filter cake was broken into smaller pieces and fines, the combustion was not disturbed. When cof ¡ring lignin with bark, the sulfur emission increased compared with bark firing only, but most of the sulfur was captured by calcium in the bark ash. Conventional sulfur capture also occurred with addition of limestone to the bed. The sulfur content in the lignin had a significantly positive effect on reducing the alkali chloride content in the deposits, thus reducing the high temperature corrosion risk. Application: This research is of interest for pulp and paper and energy and utilities companies that want to understand how kraft lignin can be used to replace fuel oil or coal in many combustion applications.
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| 15. |
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| 16. |
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| 17. |
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| 18. |
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| 19. |
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| 20. |
- Berglin, Niklas, 1966, et al.
(författare)
-
Using process integration to approach the minimum impact pulp mill
- 1997
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Ingår i: Presented at 1997 Environmental Conference and Exhibit May 5-7, 1997,Minneapolis Convention Center, Minneapolis, MN.. - 1103-2952. ; TAPPI Proceedings, s. 515-521
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Konferensbidrag (refereegranskat)abstract
- A low level of energy use is an important feature of the minimum impact mill. Process integration is used in the pulp and paper industry and other industries to reduce the use of fuels and cooling water. As the industry is in a state of rapid change, a methodical approach to process integration is useful. Pinch analysis is well established as such a tool. In the present paper, composite curves are used to analyze possibilities for process integration in combination with changes in process design. Several examples, including improved integration of the digester and analyses of the whole mill, show that this is an approach that gives good guidance early in the design process. Substantial utility savings can be identified; these are on the order of 2-4 GJ per tonne of pulp compared with already energy-efficient mills.
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| 21. |
- Bernstad Saraiva, Anna, et al.
(författare)
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Provision of pulpwood and short rotation eucalyptus in Bahia, Brazil : Environmental impacts based on lifecycle assessment methodology
- 2017
-
Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 105, s. 41-50
-
Tidskriftsartikel (refereegranskat)abstract
- Environmental impacts from cultivation of eucalyptus pulpwood and short rotation eucalyptus in northeast Brazil were investigated using lifecycle assessment methodology. The assessment considers all relevant inputs and outputs, as well as direct land use changes, assuming conversion of grassland (pasture) to areas for eucalyptus plantation. Results show that production of pulpwood eucalyptus is beneficial compared to short rotation eucalyptus in relation to all assessed impact categories, except for climate change (greenhouse gas emissions = 47 kg CO2-eq. t DM−1 pulpwood eucalyptus and 35 kg CO2-eq. t DM−1 short rotation eucalyptus). Excluding emissions from direct land use changes would increase overall GWP from investigated systems with around 5–6%, and changing the assumed land-use prior to land conversion is of decisive character for overall GWP-results from the assessed eucalyptus production systems. Modeling of nutrient balances in the short rotation production system shows a potential need to increase the input of mineral fertilizer in order to compensate for nutrient losses. This would increase environmental impacts from the short rotation system, making pulpwood eucalyptus preferable in relation to all assessed impact categories.
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| 22. |
- Berntsson, Thore, 1947, et al.
(författare)
-
Swedish Pulp Mill Biorefineries
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Wooden biomass resources have provided the basis for significant industrial activities in Sweden for more than a century. Sawn timber products and pulp and paper have dominated the use of wooden raw material for a long time, but its use for energy purposes has grown stronger during the last decades. The expansion of biomass-based combined heat and power generation is the principal example. During the last decade the climate issue has evoked the interest of producing renewable motor fuels from wood biomass, a research area, which has received increased attention for the research agenda of the Swedish Energy Agency.The development has raised questions regarding competition for raw material, production efficiency and industrial development and consequently how the raw material can be utilised in the best way for various applications. In this context, the interest has grown how various products can be manufactured within different kinds of industrial combines. Terminology differs in the literature. Terms like energy combines, bio combines, biorefineries are mentioned and this reflects the growing interest for this area but also the lack of definitions for these concepts.In the years 2005-2006 the project P22400-1,”Swedish Pulp Mill Bio Refineries” was carried out at Chalmers Institute of Technology. The final report of the project was considered to be of interest for a wider group of people and the Swedish Energy Agency has therefore decided to publish it in its report series.The project contains a literature review of projects relating to biorefineries, which have been conducted during the decade 1996-2005. The report is delimited to pulp plants as the basis for the biorefinery.The report is written in English and is intended for decision makers, governmental agencies, researchers, consultants and other stakeholders, with an interest in this field.The principal author of the report is professor Thore Berntsson, Chalmers Institute of Technology. In addition, Peter Axegård, Birgit Backlund, Åsa Samuelsson, Niklas Berglin and Karin Lindgren at STFI-Packforsk have also contributed to the report.Birgitta Palmberger
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| 23. |
- Bialik, Marta, et al.
(författare)
-
Assessment of scaling risk in a pressurized black liquor gasification pilot plant
- 2010
-
Ingår i: International Chemical Recovery Conference. ; , s. 279-286
-
Konferensbidrag (refereegranskat)abstract
- Black liquor gasification is considered as an interesting alternative to the recovery boiler-based process of green liquor production. Although the handling of the smelt in the two separate processes is similar, the final concentration and temperature of the green liquor from gasification might both be higher. This, together with the S/Na split acquired by the gasification unit, may increase the risk of scaling of slightly soluble salts during green liquor handling. This work uses a previously developed solubility model for sodium carbonate, calcium carbonate and pirssonite, CaCO 3·Na 2CO 3·H 20 in order to evaluate the scaling risk in green liquor obtained from the gasification process. The model, originally based on both gasification green liquor and regular green liquor data, was verified against new samples of green liquor from an experimental gasification unit in Sweden. During the conducted sampling campaign, the following process parameters were varied in order to establish their influence on the final liquor composition: temperature and load of the gasifier, mixing rate in the smelt dissolver, and composition of the dilution water. It has been found that varying the process parameters within the normal operational limits has a relatively small influence, on the composition of the green liquor. The risk for pirssonite precipitation in gasification green liquor was estimated as relatively low, which is consistent with earlier findings. The calculated values of the apparent solubility product were also consistent with previous results.
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| 24. |
- Consonni, Stefano, et al.
(författare)
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Black liquor-gasifier/gas turbine cogeneration
- 1997
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Ingår i: Presented at gas turbine & Aeroengine Congress & Exhibition Orlando, Florida, JUNE 2-june 5, 1997”. To be published in Transactions of the ASME.. - 1103-2952.
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Konferensbidrag (refereegranskat)
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| 25. |
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| 26. |
- Forkel, Marianne, et al.
(författare)
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Composition and functionality of the intrahepatic innate lymphoid cell-compartment in human nonfibrotic and fibrotic livers
- 2017
-
Ingår i: European Journal of Immunology. - : Wiley. - 0014-2980 .- 1521-4141. ; 47:8, s. 1280-1294
-
Tidskriftsartikel (refereegranskat)abstract
- Human innate lymphoid cells have been described to exist in different organs, with functional deregulation of these cells contributing to several disease states. Here, we performed the first detailed characterization of the phenotype, tissue-residency properties, and functionality of ILC1s, ILC2s, and ILC3s in the human adult and fetal liver. In addition, we investigated changes in the ILC compartment in liver fibrosis. A unique composition of tissue-resident ILCs was observed in nonfibrotic livers as compared with that in mucosal tissues, with NKp44− ILC3s accounting for the majority of total intrahepatic ILCs. The frequency of ILC2s, representing a small fraction of ILCs in nonfibrotic livers, increased in liver fibrosis and correlated directly with the severity of the disease. Notably, intrahepatic ILC2s secreted the profibrotic cytokine IL-13 when exposed to IL-33 and thymic stromal lymphopoetin (TSLP); these cytokines were produced by hepatocytes, hepatic stellate cells (HSCs), and Kupffer cells in response to TLR-3 stimulation. In summary, the present results provide the first detailed characterization of intrahepatic ILCs in human adult and fetal liver. The results indicate a role for ILC2s in human liver fibrosis, implying that targeting ILC2s might be a novel therapeutic strategy for its treatment.
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| 27. |
- Francey, S., et al.
(författare)
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Global survey on lime kiln operation, energy consumption and alternative fuel usage
- 2010
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Ingår i: 2010 TAPPI PEERS Conference and 9th Research Forum on Recycling. ; , s. 1004-1069
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Konferensbidrag (refereegranskat)abstract
- A survey on lime kiln operation and fuel usage was conducted through questionnaires distributed to pulp mills in nine countries in late 2008. Responses were received from 67 lime kilns at 59 pulp mills. This paper discusses the key findings from the survey with respect to kiln design parameters, operating data, control strategies, fuel types, energy consumption and operating issues; and where possible, compares them to the findings obtained from a similar survey conducted in 1991. Many improvements have been made over the past two decades to kiln design and operations, including the increased number of kilns that are equipped with product coolers and lime mud dryers, and the higher mud solids content. However, ring formation and dusting/high dust load remain the major operational issues amongst the respondents. Although few kilns have used alternative fuels to date, there is considerable industry interest in their use in the future. About two-thirds of the kilns have plans for implementing alternative fuels within the next five years.
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| 28. |
- Jansson, Mikael, et al.
(författare)
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Second generation ethanol through alkaline fractionation of pine and aspen wood
- 2010
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Ingår i: Cellulose Chemistry and Technology. - 0576-9787. ; 44:1-3, s. 47-52
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Tidskriftsartikel (refereegranskat)abstract
- Pre-treatment studies on pine and aspen wood with alkaline fractionation were performed, the experimental results obtained being used as input for assessing the conversion of an existing pulp mill to ethanol and lignin production. By the LignoBoost process, the extracted lignin could be used in the lime kiln to replace fuel oil, while the lignin not needed in the lime kiln could be sold as a by-product. In addition to fuel applications, lignin could be used in a wide range of bio-based product applications, which would increase the value of the extracted lignin and increase the total revenues. A WinGEMS model was used to calculate mass and energy balances, and the results were used for an economic evaluation of the concept. The assessment indicated that the proposed alkaline concept would have reasonable production costs from both pine and aspen wood, comparable with the bioethanol produced from grain in Northern Europe today, i.e. about 0.45 ε/L ethanol (∌5 SEK/L). The production rate of a typical mill producing 1000 tonnes of pulp per day before conversion would be in the order of 140 000 m 3 of ethanol per year, as depending on the raw wood material. The corresponding lignin production would range from 25 000 to 63 000 tonnes per year. The use of alkaline delignification to produce a substrate with low lignin content for the enzymatic hydrolysis builds entirely on known and well-proven technology, yet it needs to be further developed. The process chain from enzymatic hydrolysis to ethanol is very similar to that used today for grain ethanol. Altogether, the technical risk should therefore be low.
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| 29. |
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| 30. |
- Nordgren, Daniel, et al.
(författare)
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Studies of heat transfer and furnace temperature uniformity during combustion of oil and wood using oxygen enrichment technology
- 2011
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Ingår i: Swedish-Finnish Flame Days 2011.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- In many combustion applications a switch from fossil to renewable fuels, e.g. from fueloil to wood powder, may result in a reduction of production capacity in the boiler,furnace or kiln. Oxygen enrichment of the combustion air can be used to improve thethermal efficiency of practical combustors, i.e. reduce heat losses and promote fuelsavings. In addition, oxygen enrichment can reduce NOx emissions and also facilitateCO2 scrubbing and capture processes in such systems. In this work, flame characteristicsand furnace temperature profiles during oxygen enriched combustion were studied whenoxygen was added to the combustor at different enrichment levels by the use of a lance.The experiments were carried out in a pilot-scale furnace fired with (i) wood powder and(ii) heavy fuel oil (no.5). The results show that for the wood flame, the average furnacetemperature becomes higher and the furnace temperature profile becomes more flat.Thus, compared to conventional air combustion, there are smaller differences betweennear-burner and back-end temperatures as oxygen is added to the process. For the oilflame, as oxygen was added to the process, a higher average furnace temperature wasobserved along with a distinct shift in furnace peak temperature towards the central partsof the furnace, creating a relatively strong temperature gradient towards the back-end ofthe furnace. Comparing the two flames, the furnace temperature profile of the oxygenenriched wood flame becomes more flat compared to the oxygen enriched oil flame. Thisis interpreted as an effect of differences in overall fuel reactivity, in which the oil, being aliquid fuel, ignites and burns faster than the solid fuel wood powder. The results found inthis work shows that the burner that was used, being designed for conventional aircombustion by feeding of air through the primary, secondary and tertiary air vanes, couldhandle the changes in aerodynamics caused by the reduced air flows. The general resultsfrom this work are useful for furnace and kiln applications in which a more controllableflame and process temperature is required, e.g. in a lime kiln where a fuel switch fromfossil fuels to biomass is considered.
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| 31. |
- Pettersson, Karin, 1981, et al.
(författare)
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Integration of next-generation biofuel production in the Swedish forest industry – A geographically explicit approach
- 2015
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Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 154, s. 317-332
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Tidskriftsartikel (refereegranskat)abstract
- The geographic locations of biofuel production facilities should be strategically chosen in order to minimise the total cost of using biofuels. Proximity to biomass resources, possibilities for integration, and distance to biofuel users are aspects that need to be considered. In this paper, the geographically explicit optimisation model BeWhere Sweden was used to investigate the future production of next-generation biofuels from forest biomass in Sweden. A focus was placed on the integration of biofuel production with the existing forest industry, as well as on how different parameters affect biofuel production costs, the choice of technologies and biofuels, and the localisation of new biofuel plants. Six examples of different biofuel routes were considered. A methodology was developed considering detailed, site-specific conditions for potential host industries. The results show that the cost of biomass and the biofuel plant capital cost generally dominate the biofuel cost, but the cost for biomass transportation and biofuel distribution can also have a significant impact. DME produced via black liquor gasification (naturally integrated with chemical pulp mills) and SNG produced via solid biomass gasification (mainly integrated with sawmills), dominate the solutions. The distribution of these technology cases varies depending on a number of parameters, including criteria for sizing biofuel plants, the electricity price, the biofuel distribution cost and the cost of biomass, and is sensitive to changes in these parameters. Generally, plants with low specific investment costs (i.e., high biofuel production) and/or plants with low specific biomass transportation costs occur most frequently in the solutions. Because these properties often vary significantly among biofuel production facilities at different host industry sites of the same type, the results show the advantage of including site-specific data in this type of model.
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| 32. |
- Tomani, Per, et al.
(författare)
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The lignoboost process and use of lignin as a new bio-fuel
- 2009
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Ingår i: TAPPI Press - TAPPI Engineering, Pulping and Environmental Conference 2009 - Innovations in Energy, Fiber and Compliance. - : TAPPI Press. - 9781615677863 ; , s. 2347-2393
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Konferensbidrag (refereegranskat)abstract
- A process for lignin removal from alkaline pulping liquors (black liquors) has been developed further in the FRAM2 R&D Program (Future Resource Adapted Pulp Mill, part 2). The lignin product from a demonstration plant, which is owned and operated by Innventia (formerly STFI-Packforsk), was characterized and used in different combustion trials with good results - a co-firing of lignin and bark in a fluidized bed boiler, a co-firing with coal in a PFBC boiler (Pressurized Fluidized Bed Combustion boiler) and a firing of lignin in a full-scale lime kiln. The process development and operation of the demonstration plant has displayed good results in many ways since 2007. Runnability in the demonstration plant and the lignin quality have both been very good. Work done on the investment and operational costs showed great potential for improving the concept of economy, which is already good.
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| 33. |
- von Schenck, Anna, et al.
(författare)
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Ethanol from Nordic wood raw material by simplified alkaline soda cooking pre-treatment
- 2013
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Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 102, s. 229-240
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Tidskriftsartikel (refereegranskat)abstract
- Ethanol production from lignocellulosic raw materials will generate multiple streams, since only a certain fraction of the material can be converted into sugars and then fermented to ethanol. This requires a 'poly-generation' approach, where by-products also must have high value (e.g. lignin, sugars from hemicellulose). To reach the large scale required for profitability, it is proposed that the best way is to integrate the new processes with existing industries, preferably those that already operate biomass-to-materials or biomass-to-fuels plants. One of the largest industry branches in this respect is the pulp and paper industry. Production of second generation ethanol (or other products) via sugars from lignocellulosic materials includes a relatively costly pre-treatment of the raw material in order to separate the lignin from the cellulose. This separation of the wood components already takes place in the chemical pulp mill, and the long proven technology in pulp production known as soda cooking (pre-treatment under alkaline conditions) is further evaluated in this study. It can be directly integrated into the recovery of chemicals and energy in the pulp mill. The pre-treatment of the lignocellulosic material studied in this work is alkaline and sulphur-free, and results in a technically pure cellulose to be fed to the hydrolysis stage, which makes it different compared to most of the other processes that aim to produce ethanol from lignocelluloses. The process chain from enzymatic hydrolysis to ethanol is very similar to that being used today for grain ethanol. The aim of this study was to define the conditions in alkaline pre-treatment stage for the separation of wood to a carbohydrate fraction for hydrolysis and ethanol production, and to a lignin fraction for the production of lignin products. Aspen (Populus tremula) and pine (Pinus sylvestris) wood from Nordic mills were studied. The reference case was alkaline pre-treatment according to the well-known soda pulping technique. The pulps of alkaline pre-treated aspen could be enzymatically hydrolysed very efficiently and fermented to ethanol with high yields (82-88% ethanol yield from theoretical maximum). It should be possible to use raw material of lower quality and cost than wood from the pulp industry. However, it can then be important to be able to take out non-process elements (NPEs) that otherwise accumulate in the process. This can be done by introducing an acidic prehydolysis stage prior to the alkaline fractionation. The content of Mg and Mn ions in the wood was possible to reduce by 85-90% and Ba and Ca ions by 75-80%. Potassium was virtually completely removed during the acidic pre-treatment stage.
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| 34. |
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| 35. |
- Wetterlund, Elisabeth, et al.
(författare)
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Optimal localisation of next generation biofuel production in Sweden
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- With a high availability of lignocellulosic biomass and various types of cellulosic by-products, as well as a large number of industries, Sweden is a country of great interest for future large scale production of sustainable, next generation biofuels. This is most likely also a necessity as Sweden has the ambition to be independent of fossil fuels in the transport sector by the year 2030 and completely fossil free by 2050. In order to reach competitive biofuel production costs, plants with large production capacities are likely to be required. Feedstock intake capacities in the range of about 1-2 million tonnes per year, corresponding to a biomass feed of 300-600 MW, can be expected, which may lead to major logistical challenges. To enable expansion of biofuel production in such large plants, as well as provide for associated distribution requirements, it is clear that substantial infrastructure planning will be needed. The geographical location of the production plant facilities is therefore of crucial importance and must be strategic to minimise the transports of raw material as well as of final product. Competition for the available feedstock, from for example forest industries and CHP plants (combined heat and power) further complicates the localisation problem. Since the potential for an increased biomass utilisation is limited, high overall resource efficiency is of great importance. Integration of biofuel production processes in existing industries or in district heating systems may be beneficial from several aspects, such as opportunities for efficient heat integration, feedstock and equipment integration, as well as access to existing experience and know-how.This report describes the development of BeWhere Sweden, a geographically explicit optimisation model for localisation of next generation biofuel production plants in Sweden. The main objective of developing such a model is to be able to assess production plant locations that are robust to varying boundary conditions, in particular regarding energy market prices, policy instruments, investment costs, feedstock competition and integration possibilities with existing energy systems. This report also presents current and future Swedish biomass resources as well as a compilation of three consistent future energy scenarios.BeWhere is based on Mixed Integer Linear Programming (MILP) and is written in the commercial software GAMS, using CPLEX as a solver. The model minimises the cost of the entire studied system, including costs and revenues for biomass harvest and transportation, production plants, transportation and delivery of biofuels, sales of co-products, and economic policy instruments. The system cost is minimised subject to constraints regarding, for example, biomass supply, biomass demand, import/export of biomass, production plant operation and biofuel demand. The model will thus choose the least costly pathways from one set of feedstock supply points to a specific biofuel production plant and further to a set of biofuel demand points, while meeting the demand for biomass in other sectors.BeWhere has previously been developed by the International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria and Luleå University of Technology and has been used in several studies on regional and national levels, as well as on the European level. However, none of the previous model versions has included site-specific conditions in existing industries as potential locations for industrially integrated next generation biofuel production. Furthermore, they also usually only consider relatively few different production routes. In this project, bottom-up studies of integrated biofuel production have been introduced into a top-down model and taken to a higher system level, and detailed, site-specific input data of potential locations for integrated biofuel production has been included in the model.This report covers the first stages of model development of BeWhere Sweden. The integration possibilities have been limited to the forest industry and a few district heating networks, and the feedstocks to biomass originating from the forest. The number of biofuel production technologies has also been limited to three gasification-based concepts producing DME, and two hydrolysis- and fermentation-based concepts producing ethanol. None of the concepts considered is yet commercial on the scale envisioned here.Preliminary model runs have been performed, with the main purpose to identify factors with large influence on the results, and to detect areas in need of further development and refinement. Those runs have been made using a future technology perspective but with current energy market conditions and biomass supply and demand. In the next stage of model development different roadmap scenarios will be modelled and analysed. Three different roadmap scenarios that describe consistent assessments of the future development concerning population, transport and motor fuel demands, biomass resources, biomass demand in other industry sectors, energy and biomass market prices etc. have been constructed within this project and are presented in this report. As basis for the scenarios the report “Roadmap 2050” by the Swedish Environmental Protection Agency (EPA) has been used, using 2030 as a target year for the scenarios. Roadmap scenario 1 is composed to resemble “Roadmap 2050” Scenario 1. Roadmap scenario 2 represents an alternative development with more protected forest and less available biomass resources, but a larger amount of biofuels in the transport system, partly due to a higher transport demand compared to Roadmap scenario 1. Finally Roadmap scenario 3 represents a more “business as usual” scenario with more restrictive assumptions compared to the other two scenarios.In total 55 potential biofuel plant sites have been included at this stage of model development. Of this 32 sites are pulp/paper mills, of which 24 have chemical pulp production (kraft process) while eight produce only mechanical pulp and/or paper. Seven of the pulp mills are integrated with a sawmill, and 18 additional stand-alone sawmills are also included, as are five district heating systems. The pulp and paper mills and sawmills are included both as potential biofuel plant sites, as biomass demand sites regarding wood and bioenergy, and as biomass supply sites regarding surplus by-products. District heating systems are considered both regarding bioenergy demand and as potential plant sites.In the preliminary model runs, biofuel production integrated in chemical pulp mills via black liquor gasification (BLG) was heavily favoured. The resulting total number of required production plants and the total biomass feedstock volumes to reach a certain biofuel share target are considerably lower when BLG is considered. District heating systems did not constitute optimal plant locations with the plant positions and heat revenue levels assumed in this study. With higher heat revenues, solid biomass gasification (BMG) with DME production was shown to be potentially interesting. With BLG considered as a production alternative, however, extremely high heat revenues would be needed to make BMG in district heating systems competitive.The model allows for definition of biofuel share targets for Sweden overall, or to be fulfilled in each county. With targets set for Sweden overall, plant locations in the northern parts of Sweden were typically favoured, which resulted in saturation of local biofuel markets and no biofuel use in the southern parts. When biofuels needed to be distributed to all parts of Sweden, the model selected a more even distribution of production plants, with plants also in the southern parts. Due to longer total transport distances and non-optimal integration possibilities, the total resulting system cost was higher when all counties must fulfil the biofuel share target. The total annual cost to fulfil a certain biofuel target would also be considerably higher without BLG in the system, as would the total capital requirement. This however presumes that alternative investments would otherwise be undertaken, such as investments in new recovery boilers. Without alternative investments the difference between a system with BLG and a system without BLG would be less pronounced.In several cases the model located two production plants very close to each other, which would create a high biomass demand on a limited geographic area. The reason is that no restrictions on transport volumes have yet been implemented in the model. Further, existing onsite co-operations between for example sawmills and pulp mills have not always been captured by the input data used for this report, which can cause the consideration of certain locations as two separate plant sites, when in reality they are already integrated. It is also important to point out that some of the mill specific data (obtained from the Swedish Forest Industries Federation’s environmental database) was identified to contain significant errors, which could affect the results related to the plant allocations suggested in this report.Due to the early model development stage and the exclusion of for example many potential production routes and feedstock types, the model results presented in this report must be considered as highly preliminary. A number of areas in need of supplementing have been identified during the work with this report. Examples are addition of more industries and plant sites (e.g. oil refineries), increasing the number of other production technologies and biofuels (e.g. SNG, biogas, methanol and synthetic diesel), inclusion of gas distribution infrastructures, and explicit consideration of import and export of biomass and biofuel. Agricultural residues and energy crops for biogas production are also considered to be a very important and interesting completion to the model. Furthermore, inclusion of inte
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| 36. |
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| 37. |
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| 38. |
- Zimmer, Christine L., et al.
(författare)
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A biliary immune landscape map of primary sclerosing cholangitis reveals a dominant network of neutrophils and tissue-resident T cells
- 2021
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Ingår i: Science Translational Medicine. - : AMER ASSOC ADVANCEMENT SCIENCE. - 1946-6234 .- 1946-6242. ; 13:599
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Tidskriftsartikel (refereegranskat)abstract
- The human biliary system, a mucosal barrier tissue connecting the liver and intestine, is an organ often affected by serious inflammatory and malignant diseases. Although these diseases are linked to immunological processes, the biliary system represents an unexplored immunological niche. By combining endoscopy-guided sampling of the biliary tree with a high-dimensional analysis approach, comprehensive mapping of the human biliary immunological landscape in patients with primary sclerosing cholangitis (PSC), a severe biliary inflammatory disease, was conducted. Major differences in immune cell composition in bile ducts compared to blood were revealed. Furthermore, biliary inflammation in patients with PSC was characterized by high presence of neutrophils and T cells as compared to control individuals without PSC. The biliary T cells displayed a CD103(+)CD69(+) effector memory phenotype, a combined gut and liver homing profile, and produced interleukin-17 (IL-17) and IL-22. Biliary neutrophil infiltration in PSC associated with CXCL8, possibly produced by resident T cells, and CXCL16 was linked to the enrichment of T cells. This study uncovers the immunological niche of human bile ducts, defines a local immune network between neutrophils and biliary-resident T cells in PSC, and provides a resource for future studies of the immune responses in biliary disorders.
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