| 1. |
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| 2. |
- Ahlström, Johan, 1990, et al.
(författare)
-
Economic potential for substitution of fossil fuels with liquefied biomethane in Swedish iron and steel industry – Synergy and competition with other sectors
- 2020
-
Ingår i: Energy Conversion and Management. - : Elsevier Ltd. - 0196-8904 .- 1879-2227. ; 209
-
Tidskriftsartikel (refereegranskat)abstract
- In Sweden, the iron and steel industry (ISI) is a major source of greenhouse gas (GHG) emissions. Most of the emissions result from the use of fossil reducing agents. Nevertheless, the use of fossil fuels for other purposes must also be eliminated in order to reach the Swedish emissions reduction targets. In this study, we investigate the possibility to replace fossil gaseous and liquid fuels used for heating in the ISI, with liquefied biomethane (LBG) produced through gasification of forest residues. We hypothesize that such utilization of fuels in the Swedish ISI is insufficient to independently drive the development of large-scale LBG production, and that other sectors demanding LBG, e.g., for transportation, can be expected to influence the economic potential for the ISI to switch to LBG. The paper investigates how demand for LBG from other sectors can contribute to, or prevent, a phase-out of fossil fuels used for heating purposes in the ISI under different future energy market scenarios, with additional analysis of the impact of a CO2 emissions charge. A geographically explicit cost-minimizing biofuel production localization model is combined with heat integration and energy market scenario analysis. The results show that from a set of possible future energy market scenarios, none yielded more than a 9% replacement of fossil fuels used for heating purposes in the ISI, and only when there was also a demand for LBG from other sectors. The scenarios corresponding to a more ambitious GHG mitigation policy did not achieve higher adoption of LBG, due to corresponding higher biomass prices. A CO2 charge exceeding 200 EUR/tonCO2 would be required to achieve a full phase-out of fossil fuels used for heating purposes in the ISI. We conclude that with the current policy situation, substitution of fossil fuels by LBG will not be economically feasible for the Swedish ISI.
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| 3. |
- Ahlström, Johan, et al.
(författare)
-
Sustainable aviation fuels – Options for negative emissions and high carbon efficiency
- 2023
-
Ingår i: International Journal of Greenhouse Gas Control. - : Elsevier Ltd. - 1750-5836 .- 1878-0148. ; 125
-
Tidskriftsartikel (refereegranskat)abstract
- Mitigating the climate impact from aviation remains one of the tougher challenges in adapting society to fulfill stated climate targets. Long-range aviation cannot be electrified for the foreseeable future and the effects of combusting fuel at high altitude increase the climate impact compared to emissions of green-house gasses only, which further limits the range of sustainable fuel alternatives. We investigate seven different pathways for producing aviation biofuels coupled with either bio-energy carbon capture and storage (BECCS), or bio-energy carbon capture and utilization (BECCU). Both options allow for increased efficiency regarding utilization of feedstock carbon. Our analysis uses process-level carbon- and energy balances, with carbon efficiency, climate impact and levelized cost of production (LCOP) as primary performance indicators. The results show that CCS can achieve a negative carbon footprint for four out of the seven pathways, at a lower cost of GHG reduction than the base process option. Conversely, as a consequence of the electricity-intensive CO2 upgrading process, the CCU option shows less encouraging results with higher production costs, carbon footprints and costs of GHG reduction. Overall, pathways with large amounts of vented CO2, e.g., gasification of black liquor or bark, as well as fermentation of forest residues, reach a low GHG reduction cost for the CCS option. These are also pathways with a larger feedstock and corresponding production potential. Our results enable a differentiated comparison of the suitability of various alternatives for BECCS or BECCU in combination with aviation biofuel production. By quantifying the relative strengths and weaknesses of BECCS and BECCU and by highlighting cost, climate and carbon-efficient pathways, these results can be a source of support for both policymakers and the industry. © 2023 The Author(s)
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| 4. |
- Ahlström, Johan, et al.
(författare)
-
Value chains for integrated production of liquefied bio-SNG at sawmill sites – Techno-economic and carbon footprint evaluation
- 2017
-
Ingår i: Applied Energy. - : Elsevier BV. - 0306-2619 .- 1872-9118. ; 206, s. 1590-1608
-
Tidskriftsartikel (refereegranskat)abstract
- Industry's increasing demand for liquefied natural gas could be met in the future by liquefied methane produced from biomass feedstock (LBG - liquefied biogas). This study presents results from an investigation of value chains for integrated production of LBG at a generic sawmill site, based on gasification of sawmill waste streams and forest residues. The objective was to investigate the cost for, as well as the carbon footprint reduction associated with, production and use of LBG as a fuel. Five different LBG plant sizes were investigated in combination with three different sawmill sizes. The resulting cases differ regarding biomass feedstock composition, biomass transportation distances, LBG plant sizes, how efficiently the excess heat from the LBG plant is used, and LBG distribution distances. Pinch technology was used to quantify the heat integration opportunities and to design the process steam network. The results show that efficient use of energy within the integrated process has the largest impact on the performance of the value chain in terms of carbon footprint. The fuel production cost are mainly determined by the investment cost of the plant, as well as feedstock transportation costs, which mainly affects larger plants. Production costs are shown to range from 68 to 156 EUR/MW hfuel and the carbon footprint ranges from 175 to 250 kg GHG-eq/MW hnet biomass assuming that the product is used to substitute fossil LNG fuel. The results indicate that process integration of an indirect biomass gasifier for LBG production is an effective way for a sawmill to utilize its by-products. Integration of this type of biorefinery can be done in such a way that the plant can still cover its heating needs whilst expanding its product portfolio in a competitive way, both from a carbon footprint and cost perspective. The results also indicate that the gains associated with efficient heat integration are important to achieve an efficient value chain.
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| 5. |
- 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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| 6. |
- 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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| 7. |
- 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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| 8. |
- Andersson, Jim, et al.
(författare)
-
Co-gasification of black liquor and pyrolysis oil : Evaluation of blend ratios and methanol production capacities
- 2016
-
Ingår i: Energy Conversion and Management. - : Elsevier BV. - 0196-8904 .- 1879-2227. ; 110, s. 240-248
-
Tidskriftsartikel (refereegranskat)abstract
- The main aim of this study is to investigate integrated methanol production via co-gasification of black liquor (BL) and pyrolysis oil (PO), at Swedish pulp mills. The objectives are to evaluate techno-economically different blends ratios for different pulp mill capacities. Furthermore, the future methanol production potential in Sweden and overall system consequences of large-scale implementation of PO/BL co-gasification are also assessed.It is concluded that gasification of pure BL and PO/BL blends up to 50% results in significantly lower production costs than what can be achieved by gasification of unblended PO. Co-gasification with 20–50% oil addition would be the most advantageous solution based on IRR for integrated biofuel plants in small pulp mills (200 kADt/y), whilst pure black liquor gasification (BLG) will be the most advantageous alternative for larger pulp mills. For pulp mill sizes between 300 and 600 kADt/y, it is also concluded that a feasible methanol production can be achieved at a methanol market price below 100 €/MW h, for production capacities ranging between 0.9 and 1.6 TW h/y for pure BLG, and between 1.2 and 6.5 TW h/y for PO/BL co-gasification. This study also shows that by introducing PO/BL co-gasification, fewer pulp mills would need to be converted to biofuel plants than with pure BLG, to meet a certain biofuel demand for a region. Due to the technical as well as organizational complexity of the integration this may prove beneficial, and could also potentially lower the total investment requirement to meet the total biofuel demand in the system. The main conclusion is that PO/BL co-gasification is a technically and economically attractive production route for production biomethanol.
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| 9. |
- Andersson, Jim, et al.
(författare)
-
System studies on biofuel production via integrated biomass gasification
- 2013
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- A large number of national and international techno-economic studies on industrially integrated gasifiers for production of biofuels have been published during the recent years. These studies comprise different types of gasifiers (fluidized bed, indirect and entrained flow) integrated in different industries for the production of various types of chemicals and transportation fuels (SNG, FT-products, methanol, DME etc.) The results are often used for techno-economic comparisons between different biorefinery concepts. One relatively common observation is that even if the applied technology and the produced biofuel are the same, the results of the techno-economic studies may differ significantly.The main objective of this project has been to perform a comprehensive review of publications regarding industrially integrated biomass gasifiers for motor fuel production. The purposes have been to identify and highlight the main reasons why similar studies differ considerably and to prepare a basis for “fair” techno-economic comparisons. Another objective has been to identify possible lack of industrial integration studies that may be of interest to carry out in a second phase of the project.Around 40 national and international reports and articles have been analysed and reviewed. The majority of the studies concern gasifiers installed in chemical pulp and paper mills where black liquor gasification is the dominating technology. District heating systems are also well represented. Only a few studies have been found with mechanical pulp and paper mills, steel industries and the oil refineries as case basis. Other industries have rarely, or not at all, been considered for industrial integration studies. Surprisingly, no studies regarding integration of biomass gasification neither in saw mills nor in wood pellet production industry have been found.There are several reasons why the results of the reviewed techno-economic studies vary. Some examples are that different system boundaries have been set and that different technical and economic assumptions have been made, product yields and energy efficiencies may be calculated using different methods etc. For obvious reasons, the studies are not made in the same year, which means that different monetary exchange rates and indices have been applied. It is therefore very difficult, and sometimes even impossible, to compare the technical as well as the economic results from the different studies. When technical evaluations are to be carried out, there is no general method for how to set the system boundaries and no right or wrong way to calculate the system efficiencies as long as the boundaries and methods are transparent and clearly described. This also means that it becomes fruitless to compare efficiencies between different concepts unless the comparison is done on an exactly equal basis.However, even on an equal basis, a comparison is not a straight forward process. For example, calculated efficiencies may be based on the marginal supply, which then become very dependent on how the industries exploit their resources before the integration. The resulting efficiencies are therefore very site-dependent. Increasing the system boundaries to include all in- and outgoing energy carriers from the main industry, as well as the integrated gasification plant (i.e. total plant mass and energy balance), would inflict the same site-dependency problem. The resulting system efficiency is therefore a measure of the potential improvement that a specific industry could achieve by integrating a biomass gasification concept.When estimating the overall system efficiency of industrial biorefinery concepts that include multiple types of product flows and energy sources, the authors of this report encourage the use of electrical equivalents as a measure of the overall system efficiency. This should be done in order to take the energy quality of different energy carriers into concern.In the published economic evaluations, it has been found that there is a large number of studies containing both integration and production cost estimates. However, the number of references for the cost data is rather limited. The majority of these have also been published by the same group of people and use the same or similar background information. The information in these references is based on quotes and estimates, which is good, however none of these are publically available and therefore difficult to value with respect to content and accuracy.It has further been found that the variance in the operational costs is quite significant. Something that is particularly true for biomass costs, which have a high variance. This may be explained by natural variations in the quality of biomass used, but also to the different markets studied and the dates when the studies were performed. It may be seen from the specific investment costs that there is a significant spread in the data. It may also be seen that the differences in capital employed and process yields will result in quite large variations in the production cost of the synthetic fuels. On a general note, the studies performed are considering future plants and in some cases assumes technology development. It is therefore relevant to question the use of today’s prices of utilities and feedstock’s. It is believed that it would be more representative to perform some kind of scenario analysis using different parameters resulting in different cost assumptions to better exemplify possible futures.Due to the surprising lack of reports and articles regarding integration of biomass gasifiers in sawmills, it would be of great interest to carry out such a study. Also larger scale wood pellet production plants could be of interest as a potential gasification based biorefinery.
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| 10. |
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| 11. |
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| 12. |
- Bagheri, Marzieh, et al.
(författare)
-
Fifty years of sewage sludge management research: Mapping researchers' motivations and concerns
- 2023
-
Ingår i: Journal of Environmental Management. - : Elsevier. - 0301-4797 .- 1095-8630. ; 325
-
Tidskriftsartikel (refereegranskat)abstract
- Sewage sludge management is torn between a desire for pollution prevention and reuse of a valuable resource. Reconciling these interests in sustainable management is a challenge for researchers. This study focuses on how research on sewage sludge management practices has evolved and scrutinizes how this research is interlinked with concerns and societal issues such as contaminants, economic efficiency, and legislation. Based on published academic papers on sewage sludge management between 1971 and 2019, this study found four trends in research focused on sewage sludge management: a decreasing interest in disposal (landfilling and sea dumping), a dominant interest in land application, a growing interest in sewage sludge as product, and a stable interest in energy recovery. Research on disposal focuses on increasing sludge volumes, legislative changes, and economic challenges with an interest in waste co-treatment. Research on land application concerns nutrient use and contaminants, mainly heavy metals. Research on sewage sludge as a product focuses on the extraction of certain resources and less on use of sewage sludge specifically. Research on energy recovery of sewage sludge focuses on volume reduction rather than contaminants. Two-thirds of the papers are detailed studies aiming to improve single technologies and assessing single risks or benefits. As management of sewage sludge is multifaceted, the narrow focus resulting from detailed studies promotes some concerns while excluding others. Therefore, this study highlights potential gaps such as the combination of nutrient use and disposal and energy recovery and nutrient use.
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| 13. |
- Bagheri, Marzieh
(författare)
-
Integrated sewage sludge treatment scenarios – techno-economic analysis on energy and phosphorus recovery
- 2022
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Sewage sludge is a by-product of wastewater treatment that simultaneously gathers contaminants, valuable organic matter, and nutrients. The treatment of the increasing amount of sewage sludge is important from both pollution prevention and resource recovery perspectives as i) large shares of mineral phosphorus, listed as a critical raw material, terminate in the sewage sludge, and ii) energy recovery from sewage sludge can cover the energy-intensive demand of the treatment process. Previous research has identified sewage sludge combustion as a suitable treatment approach as it both addresses contaminant destruction and paves the way for efficient phosphorus recovery from the sewage sludge ash. The commercial development of this practice has, however, been slow. Therefore, this thesis aims to investigate the challenges in sustainable sewage sludge management, and to, in more detail, identify the economic viability of energy and phosphorus recovery from sewage sludge through combustion.The thesis’ aim is divided into two objectives addressed in three papers. First, to investigate how different aspects of sewage sludge management, such as contaminants, economic efficiency, technical aspects, and legislation, evolve and interact. This has been done by a review of sewage sludge management research over fifty years (Paper I). Second, to investigate the economic viability of simultaneous energy and phosphorus recovery from sewage sludge by comparing different technology and market scenarios. This has been done for i) new sewage sludge mono-/co-combustion plants (Paper II), and ii) the integration of treatment technologies, mainly anaerobic digestion, hydrothermal carbonization, and combustion, in an existing wastewater treatment plant (Paper III). Results from the analysis of sewage sludge management research (Paper I) show a narrow-focused perspective that often excludes inseparable aspects such as combination of economic consideration and advanced extraction technology. The investment viability of a new mono-/co-combustion of sewage sludge (Paper II) is highly conditional on heat, electricity, and fertilizer price, and external financial support is often a crucial requirement. Sewage sludge co-combustion with potassium-rich biomasses improves sewage sludge quality and forms usable ash as fertilizer without further need for phosphorus recovery technology. In this case, the economic feasibility of the process is independent of usable ash revenue, which stimulates a competitive selling price for the ash, thereby improving the marketing of sludge-based fertilizer. Avoided disposal costs of sewage sludge for a retrofitted wastewater treatment plant by introducing hydrothermal carbonization (Paper III) shows good economic feasibility while recovering phosphorus. Integrating anaerobic digestion, hydrothermal carbonization, and combustion may also improve investment incentives by improving energy outputs and phosphorus recovery. The economic feasibility is contingent on product (hydrochar, heat, electricity) prices and sensitive to added equipment costs, and costs for sludge transportation and disposal.
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| 14. |
- Bagheri, Marzieh, et al.
(författare)
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Introducing hydrothermal carbonization to sewage sludge treatment systems—a way of improving energy recovery and economic performance?
- 2023
-
Ingår i: Waste Management. - : Elsevier. - 0956-053X .- 1879-2456. ; 170, s. 131-143
-
Tidskriftsartikel (refereegranskat)abstract
- Hydrothermal carbonization (HTC) can mitigate the disposal costs of sewage sludge in a wastewater treatment plant. This study analyzes the impact of integrating HTC with anaerobic digestion (AD) and combustion from a combined energy and economic performance perspective. Net energy balance and investment opportunity are investigated for a number of technical scenarios considering i) different combinations of the technologies: AD + HTC, AD + thermal dryer + combustion, and AD + HTC + combustion, ii) different options for HTC process water treatment: wet oxidation (WO) + AD, and direct return to AD, and iii) different products: heat-only, heat and electricity, hydrochar, and phosphorus.The results show trade-offs between investment cost, self-supplement of heat, and output electricity when WO is used. In AD + HTC, net heat output decreases compared to the reference plant, but avoided disposal costs and hydrochar revenue result in profitable investment when the process water is directly returned to the AD. Although HTC has a lower heat demand than the thermal dryer, replacing the thermal dryer with HTC is only possible when AD, HTC, and combustion are connected, or when WO covers HTC’s heat demand. HTC may impair the electricity production because of the necessity for a high-temperature heat source, whereas the thermal dryer can utilize a low-temperature heat source. In conclusion, energy advantages of HTC in AD + HTC + combustion are insufficient to provide a promising investment opportunity due to high investment costs of HTC. The investment opportunity improves by co-combustion of hydrochar and external sludge.
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| 15. |
- Bagheri, Marzieh
(författare)
-
Sewage Sludge Treatment Scenarios: Techno-Economic Analyses of Energy and Phosphorus Recovery Focusing on Implementation Challenges
- 2024
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Managing sewage sludge, an inevitable by-product of wastewater treatment processes rich in both contaminants and valuable resources, presents a dual challenge: ensuring pollution prevention by immobilizing or destroying contaminants, and facilitating resource recovery. Balancing these objectives is critical given the growing volumes of sewage sludge and the imperative to both protect the environment and recover valuable resources. The unknown risks of land application of sludge, the currently most common disposal method, make thermal conversion a promising alternative, as it enables energy recovery, the breakdown of potentially harmful organic compounds, and the formation of volume-reduced, sanitized products. Despite the technical feasibility, the commercial development of advanced recovery technologies has been slow. This thesis aims to expand knowledge on different sewage sludge treatment and disposal scenarios under varying conditions; thereby shedding light on implementation challenges, local opportunities, and the financial dynamics critical for phosphorus and energy recovery from the perspectives of wastewater treatment plants, investors, and policymakers. The aim is primarily addressed by performing techno-economic analysis of sewage sludge treatment scenarios, covering the entire sludge treatment process from sludge treatment to end products and disposal (Paper II-V). The techno-economic analysis is supplemented by a review of academic research on sewage sludge management from 1971 to 2019 (Paper I). Results from the analysis of sewage sludge management research (Paper I) show a narrow-focused perspective that often misses the broader, interconnected aspects of sewage sludge management, leading to research that, while detailed, fails to capture the complexity of the field. The investment viability of a new mono-/co-combustion plant for sewage sludge (Paper II) is highly conditional on heat, electricity, and fertilizer prices, and external financial support is often a crucial requirement. Cocombustion of sludge (in low ratios) with K-rich agricultural biomass requirement in and energy demand of a thermal dryer, and by yielding ash that contains phosphorus in a plant-available form. Utilizing existing heat facility (Paper III) and co-combustion to mitigate investment costs and energy demand in sludge management showed the potential to offer a cost-effective alternative to land application. However, the viability of co-combustion hinges on both a high heat market price (Paper II) and the proximity of affordable biomass resources (Paper III). Without these conditions, co-combustion may increase the financial burden of sludge management on wastewater treatment plants and policymakers. Retrofitting a wastewater treatment plant by integrating hydrothermal carbonization in sludge treatment (Paper IV), demonstrated good economic feasibility, primarily due to the avoided disposal costs, while also recovering phosphorus. However, integrating hydrothermal carbonization in a system designed for a thermal dryer may cause a significant reduction in electricity production.Given the high moisture content of sludge and the low market prices for fertilizer, the potential revenue from energy and phosphorus recovery is inadequate to solely drive investment in advanced sewage sludge treatment technologies (Papers II-V). This issue is exacerbated by the fact that most wastewater treatment plants are small in scale. Collaborative sludge management across neighboring wastewater treatment plants (Paper V) increases phosphorus recovery capacity and leverages economies of scale, fostering investment in advanced technology. This strategy presents a significant opportunity to lower the treatment costs and offers a competitive alternative to land application, while encompassing energy and phosphorus recovery into the sludge treatment.In conclusion, resource recovery and pollution prevention in sludge management is a complex task that necessitates simultaneous consideration of technical aspects, product quality, site-specific conditions, and profitability to ensure a comprehensive and viable approach. Leveraging local infrastructure and resources in sewage sludge management is crucial, highlighting the ecessity for strategies to be tailored to the local opportunities and limitations. Such an approach outperforms mono-combustion by eliminating the investment ensures that solutions are not only environmentally sustainable but also economically viable and socially acceptable.
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| 16. |
- Bagheri, Marzieh, et al.
(författare)
-
Techno-Economic Analysis of Scenarios on Energy and Phosphorus Recovery from Mono- and Co-Combustion of Municipal Sewage Sludge
- 2022
-
Ingår i: Sustainability. - : MDPI. - 2071-1050. ; 14:5
-
Tidskriftsartikel (refereegranskat)abstract
- This study evaluates the techno-economic feasibility of energy and phosphorus (P) fertilizer (PF) recovery from municipal sewage sludge (MSS) through incineration in new combustion plants. We evaluated the economic impact of five critical process design choices: (1) boiler type, (2) fuel (MSS mono-combustion/co-combustion with wheat straw), (3) production scale (10/100 MW), (4) products (heat, electricity, PF), and (5) ash destination. Aspen Plus modeling provided mass and energy balances of each technology scenario. The economic feasibility was evaluated by calculating the minimum selling price of the products, as well as the MSS gate fees required to reach profitability. The dependency on key boundary conditions (operating time, market prices, policy support) was also evaluated. The results showed a significant dependency on both energy and fertilizer market prices and on financial support in the form of an MSS gate fee. Heat was preferred over combined heat and power (CHP), which was feasible only on the largest scale (100 MW) at maximum annual operating time (8000 h/y). Co-combustion showed lower heat recovery cost (19–30 €/MWh) than mono-combustion (29–66 €/MWh) due to 25–35% lower energy demand and 17–25% higher fuel heating value. Co-combustion also showed promising performance for P recovery, as PF could be recovered without ash post-treatment and sold at a competitive price, and co-combustion could be applicable also in smaller cities. When implementing ash post-treatment, the final cost of ash-based PF was more than four times the price of commercial PF. In conclusion, investment in a new combustion plant for MSS treatment appears conditional to gate fees unless the boundary conditions would change significantly.
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| 17. |
- Bauer, Torben
(författare)
-
Sustainable Sewage Sludge Management : Addressing Multidisciplinary Challenges
- 2023
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This PhD thesis focuses on multidisciplinary challenges in sewage sludge management and how they can be addressed to increase sustainability. Sewage sludge is the residual from wastewater treatment. It contains both resources and contaminants making its management challenging. In the past sewage sludge was often used as a fertilizer in agriculture, a practice that is still used in several countries. Today, this practice gets questioned in Europe and especially in Sweden due to the presence of contaminants in the sludge. At the same time, the resources in the sludge get into a stronger focus as society moves towards a circular economy and food production should get more resilient in a world with geopolitical challenges. In sustainable sewage sludge management, the two goals of immobilising/destroying the contaminants and utilizing the resources in the sludge are combined. This thesis identifies challenges in various disciplines and provides potential solutions to make sewage sludge management more sustainable. The discussed challenges cover the following areas: legislation (EU and Sweden), perception of sewage sludge (Sweden), research on sewage sludge management (international), and combinations of treatment methods. Results show that outdated legislation in Sweden creates insecurities, while the negative perception of sewage sludge in Swedish society further aggravates these insecurities. Although technical solutions are available or under development, e.g., treatment combinations that can separate resources and contaminants, actors in Sweden remain hesitant due to the aforementioned insecurities. This thesis emphasizes that interdisciplinary approaches, and dialogues between different actor groups and society are essential. The multitude of challenges requires solutions that combine technical and non-technical approaches. Therefore, this thesis provides recommendations for more sustainable sewage sludge management practices, including updating legislation.
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| 18. |
- Carvalho, Lara, et al.
(författare)
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Alkali enhanced biomass gasification with in situ S capture and a novel syngas cleaning : Part 2: Techno-economic analysis
- 2018
-
Ingår i: Energy. - : Elsevier. - 0360-5442 .- 1873-6785. ; 165:Part B, s. 471-482
-
Tidskriftsartikel (refereegranskat)abstract
- Previous research has shown that alkali addition has operational advantages in entrained flow biomass gasification and allows for capture of up to 90% of the biomass sulfur in the slag phase. The resultant low-sulfur content syngas can create new possibilities for syngas cleaning processes. The aim was to assess the techno-economic performance of biofuel production via gasification of alkali impregnated biomass using a novel gas cleaning systemcomprised of (i) entrained flow catalytic gasification with in situ sulfur removal, (ii) further sulfur removal using a zinc bed, (iii) tar removal using a carbon filter, and (iv) CO2 reductionwith zeolite membranes, in comparison to the expensive acid gas removal system (Rectisol technology). The results show that alkali impregnation increases methanol productionallowing for selling prices similar to biofuel production from non-impregnated biomass. It was concluded that the methanol production using the novel cleaning system is comparable to the Rectisol technology in terms of energy efficiency, while showing an economic advantagederived from a methanol selling price reduction of 2–6 €/MWh. The results showed a high level of robustness to changes related to prices and operation. Methanol selling prices could be further reduced by choosing low sulfur content feedstocks.
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| 19. |
- Carvalho, Lara, et al.
(författare)
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Methanol production via black liquor co-gasification with expanded raw material base : Techno-economic assessment
- 2018
-
Ingår i: Applied Energy. - : Elsevier. - 0306-2619 .- 1872-9118. ; 225, s. 570-584
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Tidskriftsartikel (refereegranskat)abstract
- Entrained flow gasification of black liquor combined with downstream-gas-derived synthesis of biofuels in Kraft pulp mills has shown advantages regarding energy efficiency and economic performance when compared to combustion in a recovery boiler. To further increase the operation flexibility and the profitability of the biofuel plant while at the same time increase biofuel production, black liquor can be co-gasified with a secondary feedstock (blend-in feedstock). This work has evaluated the prospects of producing biofuels via co-gasification of black liquor and different blend-in feedstocks (crude glycerol, fermentation residues, pyrolysis liquids) at different blend ratios. Process modelling tools were used, in combination with techno-economic assessment methods. Two methanol grades, crude and grade AA methanol, were investigated. The results showed that the co-gasification concepts resulted in significant increases in methanol production volumes, as well as in improved conversion efficiencies, when compared with black liquor gasification; 5-11 and 4-10 percentage point in terms of cold gas efficiency and methanol conversion efficiency, respectively. The economic analysis showed that required methanol selling prices ranging from 55-101 €/MWh for crude methanol and 58-104 €/MWh for grade AA methanol were obtained for an IRR of 15%. Blend-in led to positive economies-of-scale effects and subsequently decreased required methanol selling prices, in particular for low cost blend-in feedstocks (prices below approximately 20 €/MWh). The co-gasification concepts showed economic competitiveness to other biofuel production routes. When compared with fossil fuels, the resulting crude methanol selling prices were above maritime gas oil prices. Nonetheless, for fossil derived methanol prices higher than 80 €/MWh, crude methanol from co-gasification could be an economically competitive option. Grade AA methanol could also compete with taxed gasoline. Crude glycerol turned out as the most attractive blend-in feedstock, from an economic perspective. When mixed with black liquor in a ratio of 50/50, grade AA methanol could even be cost competitive with untaxed gasoline.
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| 20. |
- Carvalho, Lara, 1978-
(författare)
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Opportunities to broaden biomass feedstocks in thermochemical conversion technologies
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Global environmental concerns are motivating a growing interest in broadening the biomass feedstock base in several energy sectors, including (i) the domestic heating sector, presently dominated by stem wood combustion, and (ii) biofuel production, presently dominated by edible crops. The objective of this thesis is to investigate new opportunities to broaden the biomass feedstock in thermochemical conversion technologies. The performance of different feedstocks was therefore investigated for (i) heat production in small-scale combustion systems and (ii) biofuel production in large-scale gasification-based plants. The selected feedstocks were agricultural residues, forest wood, pyrolysis liquid and industrial by-products, such as lignin, black liquor, crude glycerol and fermentation residues.The alkali metals content in biomass has an important role in combustion and gasification. Alkali metals can cause ash-related problems in small-scale combustion systems, while they can catalyse gasification reactions thus increasing conversion efficiency. Keeping this effect in mind, the present investigation was based on combustion tests with pelletised agricultural residues (non-woody feedstocks with ash contents of 3-8 wt% on a dry basis) to evaluate their combustion feasibility in several small-scale appliances. Moreover, the potential techno-economic benefits of alkali addition in gasification-based biofuel plants were investigated in two different systems: (i) stand-alone biofuel plant operated with wet-alkali-impregnated forest residues and alkali-rich lignin as well as (ii) biofuel plant integrated with a Kraft pulp mill operated with black liquor (an inherently alkali-rich feedstock) mixed with different blend ratios of pyrolysis liquid, crude glycerol or fermentation residues (co-gasification concept). The techno-economic analysis in large-scale entrained-flow-gasification-based biofuel plants was made with the help of simulation tools.The combustion tests have shown that high alkali feedstocks lead to problems with ash accumulation and slag formation in small-scale appliances. The results indicated that non-woody feedstocks can only be burned in appliances adapted to manage high ash content feedstocks. Effective ash cleaning and enhanced combustion controlling mechanisms are relevant characteristics to have in appliances when using these feedstocks. It has been shown that four out of the seven selected feedstocks can be burned in small-scale appliances, while fulfilling the legal European requirements (EN 303-5:2012) in terms of combustion efficiency and emissions. The nitrogen content and ash composition were shown to be important parameters to evaluate whether a feedstock can be utilised in small-scale combustion appliances.The techno-economic investigations of the gasification-based biofuel plants have shown that alkali impregnation is an attractive option to increase energy performance and downstream biofuel production. The economic assessment has indicated that alkali impregnation does not significantly increase biofuel production costs, while it allows the application of a new syngas cleaning system that can significantly reduce biofuel production costs. The present study has shown that the vi co-gasification concept has also techno-economic benefits as a result of the (i) alkali content in black liquor and (ii) economy-of-scale effects. These benefits can be enhanced by choosing energy-rich and low-cost blend-in feedstocks. The gasification-based biofuel production routes hereby investigated exhibit a good economic performance since biofuel required selling prices were economically competitive with other biofuel production routes as well as with taxed gasoline.
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| 21. |
- Carvalho, Lara, et al.
(författare)
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Techno-economic assessment of catalytic gasification of biomass powders for methanol production
- 2017
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Ingår i: Bioresource Technology. - : Elsevier BV. - 0960-8524 .- 1873-2976. ; 237, s. 167-177
-
Tidskriftsartikel (refereegranskat)abstract
- This study evaluated the techno-economic performance and potential benefits of methanol production through catalytic gasification of forest residues and lignin. The results showed that while catalytic gasification enables increased cold gas efficiencies and methanol yields compared to non-catalytic gasification, the additional pre-treatment energy and loss of electricity production result in small or no system efficiency improvements. The resulting required methanol selling prices (90–130 €/MWh) are comparable with production costs for other biofuels. It is concluded that catalytic gasification of forest residues can be an attractive option as it provides operational advantages at production costs comparable to non-catalytic gasification. The addition of lignin would require lignin costs below 25 €/MWh to be economically beneficial.
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| 22. |
- de Jong, Sierk, et al.
(författare)
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Cost optimization of biofuel production – The impact of scale, integration, transport and supply chain configurations
- 2017
-
Ingår i: Applied Energy. - : Elsevier Ltd. - 0306-2619 .- 1872-9118. ; 195, s. 1055-1070
-
Tidskriftsartikel (refereegranskat)abstract
- This study uses a geographically-explicit cost optimization model to analyze the impact of and interrelation between four cost reduction strategies for biofuel production: economies of scale, intermodal transport, integration with existing industries, and distributed supply chain configurations (i.e. supply chains with an intermediate pre-treatment step to reduce biomass transport cost). The model assessed biofuel production levels ranging from 1 to 150 PJ a−1 in the context of the existing Swedish forest industry. Biofuel was produced from forestry biomass using hydrothermal liquefaction and hydroprocessing. Simultaneous implementation of all cost reduction strategies yielded minimum biofuel production costs of 18.1–18.2 € GJ−1 at biofuel production levels between 10 and 75 PJ a−1. Limiting the economies of scale was shown to cause the largest cost increase (+0–12%, increasing with biofuel production level), followed by disabling integration benefits (+1–10%, decreasing with biofuel production level) and allowing unimodal truck transport only (+0–6%, increasing with biofuel production level). Distributed supply chain configurations were introduced once biomass supply became increasingly dispersed, but did not provide a significant cost benefit (<1%). Disabling the benefits of integration favors large-scale centralized production, while intermodal transport networks positively affect the benefits of economies of scale. As biofuel production costs still exceeds the price of fossil transport fuels in Sweden after implementation of all cost reduction strategies, policy support and stimulation of further technological learning remains essential to achieve cost parity with fossil fuels for this feedstock/technology combination in this spatiotemporal context. © 2017 The Authors
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| 23. |
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| 24. |
- Difs, Kristina, et al.
(författare)
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Biomass gasification opportunities in a district heating system
- 2010
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Ingår i: Biomass and Bioenergy. - : Elsevier Science B.V., Amsterdam.. - 0961-9534 .- 1873-2909. ; 34:5, s. 637-651
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Tidskriftsartikel (refereegranskat)abstract
- This paper evaluates the economic effects and the potential for reduced CO2 emissions when biomass gasification applications are introduced in a Swedish district heating (DH) system. The gasification applications included in the study deliver heat to the DH network while producing renewable electricity or biofuels. Gasification applications included are: external superheater for steam from waste incineration (waste boost, WE), gas engine CHP (BIGGE), combined cycle CHP (BIGCC) and production of synthetic natural gas (SNG) for use as transportation fuel. Six scenarios are used, employing two time perspectives - short-term and medium-term - and differing in economic input data, investment options and technical system. To evaluate the economic performance an optimisation model is used to identify the most profitable alternatives regarding investments and plant operation while meeting the DH demand. This study shows that introducing biomass gasification in the DH system will lead to economic benefits for the DH supplier as well as reduce global CO2 emissions. Biomass gasification significantly increases the potential for production of high value products (electricity or SNG) in the DH system. However, which form of investment that is most profitable is shown to be highly dependent on the level of policy instruments for biofuels and renewable electricity. Biomass gasification applications can thus be interesting for DH suppliers in the future, and may be a vital measure to reach the 2020 targets for greenhouse gases and renewable energy, given continued technology development and long-term policy instruments.
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| 25. |
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| 26. |
- Fallde, Magdalena, et al.
(författare)
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Bakom drivmedelstanken - Perspektiv på svenska biodrivmedelssatsningar
- 2007
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Den här rapporten är ett resultat av ett tvärvetenskapligt projekt inom forskarskolan Program Energisystem. Syftet har varit att studera svenska satsningar på biodrivmedel ur olika perspektiv samt att undersöka motiv som har legat bakom satsningarna. De perspektiv som undersökts är ett nationellt, ett lokalt och ett teknikperspektiv. I det nationella perspektivet har statliga dokument från perioden 1990 till 2006 studerats, med syftet att få en bild av hur den svenska satsningen på biodrivmedel motiverats. I studien undersöktes vilka argument som förs fram för och emot att använda biomassa till driv¬medelsframställning. Av speciellt intresse har varit argument med anknytning till resurs- och kostnadseffektivitet. Viktiga argument som framfördes för drivmedelssatsningen var jordbrukspolitiska överväganden, försörjningstrygghet och klimatnytta. Flera gånger nämns att frågan om hur biomasseresurserna används på ett så resurseffektivt sätt som möjligt borde utredas, men någon sådan utredning blev aldrig av.Det lokala perspektivet har studerats genom att undersöka Linköpings övergång till biogasdrift i tätortsbussarna. Centrala frågor är framför allt vilka aktörer som varit drivande i biogassatsningen samt vilka intressen som inverkat. I kapitlet visas hur olika aktörer företrädande kommunen, det kommunala energibolaget samt de kommunala och regionala transportbolagen varit drivande i satsningen. Aktörerna har tolkat biogassatsningen på olika sätt; som energi-, transport- och miljörelaterad fråga och har därför haft olika intressen i skeendet. Biogas har fungerat som ett gränsobjekt, det vill säga en lösning som passar alla parter, genom att sammanfoga de olika aktörernas intressen och möjliggöra ett möte mellan transport, energi och miljö på lokal nivå.För teknikperspektivet har fokus legat på undersökningar av teknikerna för framställning av framtidens biodrivmedel, med utgångspunkt i de tre utvecklingsanläggningar för dessa som finns i Sverige idag. I rapporten beskrivs den historiska bakgrunden till de tre utvecklingsanläggningarna; cellulosaetanolsanläggningen i Örnsköldsvik, förgasningsanläggningen för fast biomassa i Värnamo och svartlutsförgasningsanläggningen i Piteå. Utvecklingsanläggningarna pratas ofta om i klump som om det vore ett projekt, men av de historiska överblickarna för anläggningarna framgår att de i högsta grad är tre separata företeelser. De tre teknikerna och dess status beskrivs och en utblick för framtiden ges för respektive teknik. Vikten av integration av drivmedelsproduktionen diskuteras. Vidare problematiseras möjligheterna med att jämföra olika biodrivmedel för att exempelvis kunna värdera deras klimat- eller försörjningstrygghetsnytta, jämföra energi-, resurs- och kostnadseffektivitet etcetera. Ett antal rapporter om teknikerna för framställning och användning av alternativa drivmedel har studerats, främst studier som behandlar de tre utvecklingsanläggningsteknikerna. En diskussion förs kring vilka typer av nyckeltal som används för att jämföra biodrivmedel i dessa studier. Vidare visas på grundläggande skillnader i systemavgränsningar, antaganden om omgivande system etcetera och hur dessa skillnader påverkar resultatet. Exempelvis har vilken status som antas för tekniken, hur över- eller underskott av el värderas, liksom hur biprodukter och överskottsvärme hanteras stor betydelse. Olika studier tenderar att hantera dessa saker på olika sätt, vilket gör det mycket svårt att göra relevanta jämförelser. I den avslutande diskussionen resoneras kring de olika perspektiven på svenska biodrivmedelssatsningar med hjälp av tre teman; klimatpåverkan, oljeberoende och försörjningstrygghet samt nyckeltal för att jämföra biodrivmedel. Såväl likheter som skillnader mellan perspektiven har påvisats, och det har funnits svårt att urskilja en röd tråd i den svenska biodrivmedelssatsningen. Likaså kan motiven till biodrivmedelssatsningarna ifrågasättas; vilka argument som påverkat satsningarna skiljer sig åt i respektive perspektiv, och tenderar även att förändras med tiden.
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| 27. |
- Fallde, Magdalena, et al.
(författare)
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Energy System Models as a Means of Visualising Barriers and Drivers of Forest-Based Biofuels : An Interview Study of Developers and Potential Users
- 2017
-
Ingår i: Sustainability. - : MDPI. - 2071-1050. ; 9:10
-
Tidskriftsartikel (refereegranskat)abstract
- Forest-derived biofuels have been on the agenda for several decades. Despite extensive research and development efforts, forest biofuel concepts have nevertheless not yet been realized on any significant scale. The discrepancy between the expectations from the research community and the lack of momentum regarding biofuel production raises the question of if and how research results can be used to achieve such goals. Here, we report results from an interview study with the aim of evaluating how energy system models can be used to illustrate barriers and drivers for forest biofuels, with focus on Swedish conditions, using the BeWhere model as case. The study is framed as an example of expertise, and problematizes how energy system models are interpreted among expected users. While the interviews revealed some general scepticism regarding models, and what kinds of questions they can answer, the belief was also expressed that increased complexity might be an advantage in terms of being able to accommodate more barriers against forest biofuels. The study illustrates the complexity of this policy area, where an energy system model can answer some, but never all, ‘what if…?’ questions. The results reveal a need for reformation in energy system modelling in order to more explicitly make society the subject of the work, and also illustrate that the belief in expertise as a tool for consensus-building in decision-making should be questioned.
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| 28. |
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| 29. |
- Flink, Mimmi, et al.
(författare)
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Comparing new Swedish concepts for production of second generation biofuels - evaluating CO2 emissions using a system approach
- 2007
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Ingår i: SETAC Europe 14th LCA Case Studies Symposium, 3-4 December 2007, Göteborg, Sweden. ; , s. 99-102
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Well-to-wheels studies and various figures of merit are often used to assess the benefits of different biofuels regarding for example climate effect, security of supply, energy efficiency, resource efficiency and costs. However, fundamental differences in system boundaries, assumptions about surrounding systems etc. influence the results when comparing biofuels. This work focuses on well-to-wheel studies of second generation biofuels, in particular the technologies represented by the three development plants in Sweden, i.e. cellulosic ethanol in Örnsköldsvik, biomass gasification in Värnamo, and black liquor gasification in Piteå. The discussion includes potential to improve comparisons by for example including byproducts, e.g. heat, the influence of energy integration of the production process, and CCS in biofuel production as a way to improve climate benefits from biofuels.
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| 30. |
- Furusjö, Erik, 1972-, et al.
(författare)
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Alkali enhanced biomass gasification with in situ S capture and novel syngas cleaning. Part 1 : Gasifier performance
- 2018
-
Ingår i: Energy. - : Elsevier Ltd. - 0360-5442 .- 1873-6785. ; 157, s. 96-105
-
Tidskriftsartikel (refereegranskat)abstract
- Previous research shows that alkali addition in entrained flow biomass gasification can increase char conversion and decrease tar and soot formation through catalysis. This paper investigates two other potential benefits of alkali addition: increased slag flowability and in situ sulfur capture. Thermodynamic equilibrium calculations show that addition of 2–8% alkali catalyst to biomass completely changes the chemical domain of the gasifier slag phase to an alkali carbonate melt with low viscosity. This can increase feedstock flexibility and improve the operability of an entrained flow biomass gasification process. The alkali carbonate melt also leads to up to 90% sulfur capture through the formation of alkali sulfides. The resulting reduced syngas sulfur content can potentially simplify gas cleaning required for catalytic biofuel production. Alkali catalyst recovery and recycling is a precondition for the economic feasibility of the proposed process and is effected through a wet quench. It is shown that the addition of Zn for sulfur precipitation in the alkali recovery loop enables the separation of S, Ca and Mg from the recycle. For high Si and Cl biomass feedstocks, an alternative separation technology for these elements may be required to avoid build-up.
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| 31. |
- Furusjö, Erik, et al.
(författare)
-
Co-gasification of pyrolysis oil and black liquor - a new track for production of chemicals and transportation fuels from biomass
- 2015
-
Konferensbidrag (refereegranskat)abstract
- Pressurized oxygen-blown entrained flow black liquor (BL) gasification, the Chemrec technology, has been demonstrated in a 3 MWth pilot plant in Piteå, Sweden for more than 25,000 h. The plant is owned and operated by Luleå University of Technology since 2013. It is well known that catalytic activity of alkali metals is important for the high reactivity of black liquor, which leads to a highly efficient BL gasification process. The globally available volume of BL is however limited and strongly connected to pulp production. By co-gasifying pyrolysis oil (PO) with BL it is possible to utilize the catalytic activity also for PO conversion to syngas. Adding PO leads to larger feedstock flexibility with the possibility of building larger biofuels plants based on BL gasification technology. This presentation summarizes new results from research activities aimed at developing and assessing the PO/BL co-gasification process. Results from laboratory experiments with PO/BL mixtures show that pyrolysis behavior and char gasification reactivity are similar to pure BL. This means that the decrease in the alkali metal concentration due to the addition of PO in the mixture does not decrease the reactivity. Pure PO is much less reactive. Mixing tests show that the fraction of PO that can be mixed into BL is limited by lignin precipitation as a consequence of PO acidity. Pilot scale PO/BL co-gasification experiments have been executed following design and construction of a new feeding system to allow co-feeding of PO with BL. The results confirm the conclusions from the lab scale study and prove that the co-gasification concept is practically applicable. Process performance of the pilot scale co-gasification process is similar to gasification of BL only with high carbon conversion and clean syngas generation. This indicates that the established BL gasification technology can be used for co-gasification of PO and BL without major modifications.
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| 32. |
- Höltinger, Stefan, et al.
(författare)
-
The impact of climatic extreme events on the feasibility of fully renewable power systems : a case study for Sweden
- 2019
-
Ingår i: Energy. - : Elsevier. - 0360-5442 .- 1873-6785. ; 178, s. 695-713
-
Tidskriftsartikel (refereegranskat)abstract
- Long term time series of variable renewable energy (VRE) generation and electricity demand (load) provide important insights into the feasibility of fully renewable power systems. The coverage of energy statistics is usually too short or the temporal resolution too low to study effects related to interannual variability or the impact of climatic extreme events. We use time series simulated from climate data to assess the frequency, duration, and magnitude of extreme residual load events of two fully renewable power scenarios with a share of VRE generation (wind and solar PV) of about 50% for the case of Sweden. We define residual load as load – wind – PV – nuclear generation. Extreme residual load events are events that exceed the balancing or ramping capacities of the current power system. For our analysis, we use 29 years of simulated river runoff and wind and PV generation. Hourly load is derived from MERRA reanalysis temperature data by applying statistical models. Those time series are used along with historic capacity and ramping restrictions of hydro and thermal power plants in an optimization model to minimize extreme residual load events. Our analysis shows that even highly flexible power systems, as the Swedish one, are affected by climatic extreme events if they increase their VRE shares. Replacing current nuclear power capacities by wind power results on average in three extreme residual load events per year that exceed the current power system’s flexibility. Additional PV generation capacities instead of wind increase the number of extreme residual load events by about 4 %, as most events occur during the winter month when solar generation is close to zero and thus not able to counterbalance low wind events. Contrarily, overproduction and the need to curtail VRE generation become more pressing with higher shares of PV. In the discussion we highlight measures that could provide additional balancing capabilities to cope with the more frequent and severe residual load events in a fully renewable power system with high shares of VRE generation.
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| 33. |
- Höltinger, Stefan, et al.
(författare)
-
Using long term synthetic time series to assess the impact of meteorological extreme events on renewable energy systems : a case study of wind and hydro power in Sweden
- 2017
-
Ingår i: Geophysical Research Abstracts. - : Copernicus Publications. - 1029-7006 .- 1607-7962. ; 19
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Synthetic time series of renewable energy generation provide important inputs for energy system models that study the transition to low carbon energy systems. The coverage of national energy statistics is usually too short or temporal resolution too low – in particular if meteorological extreme events should be assessed. These extreme events may put high stress on power systems with very high shares of renewables and therefore have to be studied in detail. We use simulated time series of Swedish wind energy generation for a 35 year period based on MERRA reanalysis datasets. The simulation of hydropower generation is more complex and requires hydrological models that combine precipitation data with spatially explicit information on soil type and land cover to simulate river discharge. For this purpose, we use time series of daily river discharge that have been simulated using the open source model HYPE (HYdrological Predictions for the Environment).We compared the derived time series for wind and hydropower generation in the four Swedish bidding areas with respect to their long-term correlation, patterns of seasonality, and length and duration of extreme events. Preliminary results show that expanding wind power capacities could significantly reduce the overall variability of renewable energy generation. Furthermore, the frequency and duration of extreme production events in a combined wind-hydropower system is lower than in a hydropower system only. Further work will study the need for backup capacities in a future Swedish power system with very high shares of hydro, wind and solar power (>90%).
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| 34. |
- Jafri, Yawer, 1988-, et al.
(författare)
-
Combining expansion in pulp capacity with production of sustainable biofuels – Techno-economic and greenhouse gas emissions assessment of drop-in fuels from black liquor part-streams
- 2020
-
Ingår i: Applied Energy. - : Elsevier Ltd. - 0306-2619 .- 1872-9118. ; 279
-
Tidskriftsartikel (refereegranskat)abstract
- Drop-in biofuels from forest by-products such as black liquor can help deliver deep reductions in transport greenhouse gas emissions by replacing fossil fuels in our vehicle fleet. Black liquor is produced at pulp mills that can increase their pulping capacity by upgrading some of it to drop-in biofuels but this is not well-studied. We evaluate the techno-economic and greenhouse gas performance of five drop-in biofuel pathways based on BL lignin separation with hydrotreatment or black liquor gasification with catalytic synthesis. We also assess how integrated biofuel production impacts different types of pulp mills and a petroleum refinery by using energy and material balances assembled from experimental data supplemented by expert input. Our results indicate that drop-in biofuels from black liquor part-streams can be produced for ~80 EUR2017/MWh, which puts black liquor on the same footing (or better) as comparable forest residue-based alternatives. The best pathways in both production routes have comparable costs and their principal biofuel products (petrol for black liquor gasification and diesel for lignin hydrotreatment) complement each other. All pathways surpass European Union's sustainability criteria for greenhouse gas savings from new plants. Supplementing black liquor with pyrolysis oil or electrolysis hydrogen can improve biofuel production potentials and feedstock diversity, but better economic performance does not accompany these benefits. Fossil hydrogen represents the cheaper option for lignin hydrotreatment by some margin, but greenhouse gas savings from renewable hydrogen are nearly twice as great. Research on lignin upgrading in industrial conditions is recommended for reducing the presently significant performance uncertainties. © 2020 The Authors
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| 35. |
- Jafri, Yawer, 1988-, et al.
(författare)
-
Double Yields and Negative Emissions? : Resource, Climate and Cost Efficiencies in Biofuels With Carbon Capture, Storage and Utilization
- 2022
-
Ingår i: Frontiers in Energy Research. - : Frontiers Media S.A.. - 2296-598X. ; 10
-
Tidskriftsartikel (refereegranskat)abstract
- As fossil-reliant industries turn to sustainable biomass for energy and material supply, the competition for biogenic carbon is expected to intensify. Using process level carbon and energy balance models, this paper shows how the capture of residual CO2 in conjunction with either permanent storage (CCS) or biofuel production (CCU) benefits fourteen largely residue-based biofuel production pathways. With a few noteworthy exceptions, most pathways have low carbon utilization efficiencies (30–40%) without CCS/U. CCS can double these numbers and deliver negative emission biofuels with GHG footprints below −50 g CO2 eq./MJ for several pathways. Compared to CCS with no revenue from CO2 sequestration, CCU can offer the same efficiency gains at roughly two-third the biofuel production cost (e.g., 99 EUR/MWh vs. 162 EUR/MWh) but the GHG reduction relative to fossil fuels is significantly smaller (18 g CO2 eq./MJ vs. −99 g CO2 eq./MJ). From a combined carbon, cost and climate perspective, although commercial pathways deliver the cheapest biofuels, it is the emerging pathways that provide large-scale carbon-efficient GHG reductions. There is thus some tension between alternatives that are societally best and those that are economically most interesting for investors. Biofuel pathways vent CO2 in both concentrated and dilute streams Capturing both provides the best environomic outcomes. Existing pathways that can deliver low-cost GHG reductions but generate relatively small quantities of CO2 are unlikely to be able to finance the transport infrastructure required for transformative bio-CCS deployment. CCS and CCU are accordingly important tools for simultaneously reducing biogenic carbon wastage and GHG emissions, but to unlock their full benefits in a cost-effective manner, emerging biofuel technology based on the gasification and hydrotreatment of forest residues need to be commercially deployed imminently. Copyright © 2022 Jafri, Ahlström, Furusjö, Harvey, Pettersson, Svensson and Wetterlund.
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| 36. |
- Jafri, Yawer, 1988-, et al.
(författare)
-
Multi-aspect evaluation of integrated forest-based biofuel production pathways : Part 2, economics, GHG emissions, technology maturity and production potentials
- 2019
-
Ingår i: Energy. - : Elsevier. - 0360-5442 .- 1873-6785. ; 172, s. 1312-1328
-
Tidskriftsartikel (refereegranskat)abstract
- Promoting the deployment of forest-based drop-in and high blend biofuels is considered strategically important in Sweden but many aspects of the overall performance of the foremost production technologies are as yet unexamined. This paper evaluates the technology maturity, profitability, investment requirements, GHG performance and Swedish biofuel production potential of six commercially interesting forest-based biofuel production pathways.Significant heterogeneity in technology maturity was observed. Lack of technical demonstration in industrially representative scales renders the liquefaction-hydrotreatment route for drop-in biofuels less mature than its gasification-catalytic upgrading counterpart. It is a paradox that short-term priority being accorded to pathways with the lowest technology maturity. Nth-of-a-kind investments in (a) gasification-based methanol, (b) hydropyrolysis-based petrol/diesel, and (c) lignin depolymerization-based petrol/diesel were profitable for a range of plant sizes. The profitability of pulp mill-integrated small gasification units (<100 MW) goes against the common perception of gasification being economically feasible only in large scales. New low-cost options for debottlenecking production at recovery boiler-limited kraft mills appear worth investigating. GHG emission reductions ranged from 66 to 95%; a penalty was incurred for high consumption of natural gas-based hydrogen. Swedish biofuel production potentials ranged from 4 to 27 TWh/y but a more feasible upper limit is 12–15 TWh/y.
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| 37. |
- Jafri, Yawer, 1988-, et al.
(författare)
-
Multi-aspect evaluation of integrated forest-based biofuel production pathways : Part 1. Product yields & energetic performance
- 2019
-
Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 166, s. 401-413
-
Tidskriftsartikel (refereegranskat)abstract
- Forest-based biofuels are strategically important in forest-rich countries like Sweden but the technical performance of several promising production pathways is poorly documented. This study examines product yields and energy efficiencies in six commercially relevant forest-based “drop-in” and “high blend” biofuel production pathways by developing detailed spreadsheet energy balance models. The models are in turn based on pilot-scale performance data from the literature, supplemented with input from technology developers and experts. In most pathways, biofuel production is integrated with a market pulp mill and/or a crude oil refinery. Initial conversion is by pyrolysis, gasification or lignin depolymerization and intermediate products are upgraded by hydrotreatment or catalytic synthesis. While lignin oil (LO) hydrodeoxygenation had the highest expanded system efficiency, considerable uncertainty surrounds product yields owing to absence of suitable experimental data on LO upgrading. Co-feeding vacuum gas oil and fast pyrolysis oil in a fluidized catalytic cracker has a complex and uncertain effect on fossil yields, which requires further investigation. Co-locating bio-oil hydrotreatment at the refinery improves heat utilization, leading to higher system efficiencies. Explicit consideration of mill type and energy requirements is required to avoid performance misestimation as an assumption of energy surplus can confer a definite advantage.
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| 38. |
- Krook Riekkola, Anna, et al.
(författare)
-
Biomassa, systemmodeller och målkonflikter
- 2017
-
Rapport (refereegranskat)abstract
- I denna studie analyseras tillgängligheten av och konkurrensen om biobränsle med ett fjärrvärmeperspektiv. Syftet är att bidra till en breddad systemförståelse av interaktionen mellan fjärrvärmesystemet, skogsbiomassasystemet och biodrivmedelssystemet. Utgångspunkten har varit två energisystemmodeller som på olika sätt fångar konkurrens-en om svensk biomassa. Fokus har varit på att (1) identifiera eventuella målkonflikter mellan ökad elproduktion från fjärrvärme, ökad andel biodrivmedel och minskade koldioxidutsläpp, och (2) identifiera hur modellerna kan kommunicera och vidareutvecklas i syfte att förbättra representationen av biomassa i den nationella energisystemanalysen.
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| 39. |
- Leduc, Sylvain, et al.
(författare)
-
Biofuel production in Europe - Potential from lignocellulosic waste
- 2010
-
Ingår i: Proceedings Venice 2010, Third International Symposium on Energy from Biomass and Waste. - Venice, Italy : CISA, Environmental Sanitary Engineering Centre.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The objective of this study is to analyze the biofuel potential in Europe fromlignocellulosic waste (wood waste and paper and cardboard waste). Ethanol from fermentationand Fischer-Tropsch (FT) diesel from gasification are the two biofuels considered. As thosebiofuels are not yet commercially available, the optimal locations of the production plants haveto be determined. The analysis is carried out with a geographic explicit model that minimizes thetotal cost of the biofuel supply chain. A mixed integer linear program is used for theoptimization. The results show that ethanol production plants are selected in a majority of thestudied cases. Ethanol plants are mainly set up in areas with a high heat demand and/or highelectricity or heat price, whereas FT diesel production plants are set up in areas where the heatdemand is low all year round. A high cost for emitting CO2 as well as high transport fossil fuelprices favor the selection of FT diesel over ethanol production plants. With a CO2 cost of 100€/tCO2 applied, the biofuel production from waste can potentially meet around 4% of theEuropean transport fuel demand.
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| 40. |
- Leduc, Sylvain, et al.
(författare)
-
CHP or biofuel production in Europe?
- 2012
-
Ingår i: Energy Procedia. - : Elsevier. - 1876-6102. - 9781627484299 ; 20, s. 40-49
-
Tidskriftsartikel (refereegranskat)abstract
- In this study, the opportunity to invest in combined heat and power (CHP) plants and second-generation biofuel production plants in Europe is investigated. To determine the number and type of production plants, a mixed integer linear model is used, based on minimization of the total cost of the whole supply chain. Different policy scenarios are studied with varying values of carbon cost and biofuel support. The study focuses on the type of technology to invest in and the CO2 emission substitution potential, at constant energy prices. The CHP plants and the biofuel production plants are competing for the same feedstock (forest biomass), which is available in limited quantities. The results show that CHP plants are preferred over biofuel production plants at high carbon costs (over 50 EUR/tCO2) and low biofuel support (below 10 EUR/GJ), whereas more biofuel production plants would be set up at high biofuel support (over 15 EUR/GJ), irrespective of the carbon cost. Regarding the CO2 emission substitution potential, the highest potential can be reached at a high carbon cost and low biofuel support. It is concluded that there is a potential conflict of interest between policies promoting increased use of biofuels, and policies aiming at decreased CO2 emissions.
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| 41. |
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| 42. |
- Lundgren, Joakim, et al.
(författare)
-
Development of a regional-economic process integration model for Billerud Karlsborg AB
- 2010
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The pulp and paper industry is an energy-intensive industrial sector that faces several challenges such as increased competition and rising feedstock and energy prices. To adress this, it is crucial for the industry to improve the material and energy efficiencies to the greatest possible extent. Process integration methods like pinch analysis and mathematical programming are useful tools for evaluating possible process alternatives, i.e. applications of new technologies, changes to new equipment and/or different operating conditions. Development of industrial energy combines is an interesting approach towards an overall optimization of energy and material flows. One problem is often that there are a large number of essentially different actors and financers that are interested in studying other parameters than those that are normally investigated in process integration studies, for example national or regional economics and various social values.In this project, engineering, economic and statistical tools and methods have been applied separately as well as in combination for different types of investigations conducted at the paper and pulp mill Billerud Karlsborg AB in Kalix, Sweden. One main objective has been to develop a process integration model of the mill based on the reMIND method to be used for introductory process simulations of the existing mill configuration. Additionally, pinch analysis has been used to identify alternatives for energy savings in the mill. Another objective has been to develop a regional economic market model (ReCOM) that should be suitable for analysis and predictions of price changes on relevant feedstock markets. A more simplified model based on the reMIND method has been used for intitial studies on how the mill can be turned into a biorefinery. The main purpose of that work has been to investigate if biomass gasification can be economically interesting for the mill and if so, under what boundary conditions. A statistical technique, conjoint analysis, has been used to study and analyze the attitude of employed people at the mill to changes in the production process that may affect for example the local and global environment etc. Finally, possible interactions between the different models and tools have been investigated.The reMIND modelling of the existing mill configuration has showed several alternatives to save steam and fuel. For example, if the wood-chips supplied to the digester is pre-heated from a temperature of 0°C to say 60°C by the use of low grade residual heat, approximately 1.5 ton per hour of 10 bar steam or 5 ton per hour of biomass fuels can theoretically be saved. Furthermore, if the inlet liquor temperature to effect 4 of the evaporation plant increases from 85 to 105°C, the steam used for evaporation decreases from 77 to 66 ton per hour and as a consequence, the biomass fuel supply to the bark boiler decreases from 51 to 39 ton per hour. This, however, also leads to a slightly reduced electricity production, from 35 to 34 MW due to a reduced production of the high pressure steam.The results from the developed ReCOM model, suggest that only none to small changes in the fibrous input prices from an increase in the fuel price (affecting the forestry sector) and a small price increase as a result from a reduced supply of purchasable wood-chips and pulp wood. The small effect that increasing fuel prices has on the fibrous input prices can largely be explained by the relatively small cost share that fuels have in the forestry sector. An increase of the labour costs would most likely have a larger impact. As for the price effect from a reduction in the supply of purchasable wood-chips, there is a substitution possibility between purchased and internally produced wood-chips for the pulp mill. However, when the limit for how much internally produced wood-chips is reached its will probably results in larger price effectsThe Pinch study of the mill indicated that there is a theoretical steam-saving potential of 18.5 MW, corresponding to 12% of the current steam demand. Two different retrofit proposals were suggested for how to achieve specific steam saving levels in practice. According to a basic retrofit proposal, a steam saving of 5.8 MW could be achieved at an investment cost of 7 MSEK while a more rigorous retrofit would enable steam savings of 11 MW at an investment cost of 14.5 MSEK. An approach for using these results in a reMIND model of the mill has also been proposed.The results from the more simplified reMIND modelling have showed that if the mill starts to produce DME via biomass gasification, the necessary policy support to make it economically feasible ranges from 92-561 SEK per MWh biofuel (DME) over four different future scenarios. This could be compared to the Swedish exemption from energy tax on biofuels, which currently amounts to approximately 275 SEK per MWh. It is also concluded that biomass gasification results in a larger net CO2 reduction when integrated with the pulp and paper mill, than when the mill and the gasification plant operate separately.The conjoint analysis showed that it is possible to find groups of respondents that were unknown prior to the study. If an organisation wants to implement a change in the process, conjoint analysis can be used to identify groups of participants with similar preferences and then tailor information to suit these specific groups.Many possibilities for the different models to interact have been identified and illustrated. The interaction between the reMIND method and ReCOM is based on exchanging information on fibrous input prices and quantities and conducted through an iterative process. The results indicate that the models can interact to produce more robust and reliable conclusions regarding optimal resource utilization suggesting that the described approach is feasible and that further research efforts can be made to extend the models. Pinch analysis and reMIND modelling has in other studies shown to be able to interact iteratively. In this study, the retrofit proposals obtained from the pinch analysis could serve as inputs to future reMIND modelling. Another interaction between reMIND and pinch analysis that has been identified during the project is to use pinch analysis to evaluate the opportunity to pre-heat certain process streams. The results from a conjoint analysis are quantitative in form of regression coefficients. However, to use these numbers for example in a Pareto front analysis will be difficult as the numbers has no monetary, energy or emission unit. Nonetheless, conjoint analysis can interact in many different ways with ReCOM as well as the reMIND models. For example, to choose scenarios to be modelled in ReCOM where the factors in the conjoint analysis can be tailored to indicate how the market would respond in a hypothetical situation. Conjoint analysis can be used to weight different factors in the reMIND model. The weighting can possibly also be used in the ReCOM model.This work has illustrated how the various engineering, economic and statistical methods and tools can be used both separately and in combination to help an industry towards more energy-efficient production processes.
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| 43. |
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| 44. |
- Lundmark, Robert, et al.
(författare)
-
On the green transformation of the iron and steel industry: Market and competition aspects of hydrogen and biomass options
- 2024
-
Ingår i: Biomass and Bioenergy. - : Elsevier. - 0961-9534 .- 1873-2909. ; 182
-
Tidskriftsartikel (refereegranskat)abstract
- The iron and steel industry is a major emitter of carbon dioxide globally. To reduce their carbon footprint, the iron and steel industry pursue different decarbonization strategies, including deploying bio-based materials and energy carriers for reduction, carburisation and/or energy purposes along their value-chains. In this study two potential roles for biomass were analysed: (a) substituting for fossil fuels in iron-ore pellets induration and (b) carburisation of DRI (direct reduced iron) produced via fully hydrogen-based reduction. The purpose of the study was to analyse the regional demand-driven price and allocative effects of biomass assortments under different biomass demand scenarios for the Swedish iron and steel industry. Economic modelling was used in combination with spatial biomass supply assessments to predict the changes on relevant biomass markets. The results showed that the estimated demand increases for forest biomass will have significant regional price effects. Depending on scenario, the biomass demand will increase up to 25 percent, causing regional prices to more than doubling. In general, the magnitude of the price effects was driven by the volumes and types of biomasses needed in the different scenarios, with larger price effects for harvesting residues and industrial by-products compared to those of roundwood. A small price effect of roundwood means that the incentives for forest-owners to increase their harvests, and thus also the availability of harvest residues, are small. Flexibility in the feedstock sourcing (both regarding quality and geographic origin) will thus be important if forest biomass is to satisfy demands in iron and steel industry.
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| 45. |
- Lundmark, Robert, et al.
(författare)
-
Projekt: En hållbar omställning av energisystemet mot en ökad andel bioenergi
- 2016
-
Annan publikation (populärvet., debatt m.m.)abstract
- 3 PhD projects: Markets and price formulation (LTU, economics); Technologies and value chains (Chalmers) and; Location and industrial change (LTU, energy engineering). The general system perspective has its starting point in the importance of biomass and bioenergy in the transition to a long-run sustainable energy system and to an efficient spatial resource utilization and production with increased value chains. Focus is on biorefineries. A spatial approach will be applied in combination with national energy system modelling in connection with technological development potentials and industrial applications is linked to the feed-stock supply as well as market and policy issues.
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| 46. |
- Lundmark, Robert, et al.
(författare)
-
Projekt: Storskalig utbyggnad av bioraffinaderier: Nya värdekedjor, produkter och effektivt utnyttjande av skoglig biomassa
- 2016
-
Annan publikation (populärvet., debatt m.m.)abstract
- Utvecklingen av kommersiella bioraffinaderikoncept är av strategisk betydelse för Sveriges utveckling till en biobaserad ekonomi. Bioraffinaderier bidrar till att ersätta fossila med biobaserade råvaror. Dessutom bidrar de till en smartare användning av biomassa, ökat förädlingsvärde samt utvecklingspotentialen av nya bioprodukter. Tekniska potentialer och industriella tillämpningar sammanlänkas med råvaruförsörjning samt marknads-, innovations- och policyaspekter. Projektet är tvärvetenskapligt och omfattar integration av modeller som kan redogöra för samspelet mellan olika sektorer, som inkluderar geografiska variationer av utbud och efterfrågan av skoglig biomassa, och som kan fånga effekterna av förändrade marknadsvillkor och styrmedel. För modellintegrationen kommer verktyg tas fram för att underlätta kommunikation och återkoppling mellan de ingående modellerna. Projektet syftar till att generera ny kunskap och ett modellramverk för avancerade systemanalyser relaterade till (i) den svenska biomassa och dess roll i ett hållbart energisystem och (ii) industriell omvandling av processindustrin i riktning mot ett framtida bioraffinaderi branschen. Genomförandefasen bygger på tre uppgiftsområden.
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| 47. |
- Lundmark, Robert, et al.
(författare)
-
Supply assessment of forest biomass : A bottom-up approach for Sweden
- 2015
-
Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 75, s. 213-226
-
Tidskriftsartikel (refereegranskat)abstract
- As there is increasing interest in the use of biomass for energy in Sweden, the potential availability and harvesting costs of forest roundwood, harvesting residues and stumps were estimated up to the year 2069 in 10-year intervals, using a high spatial resolution GIS. In each individual forest area, an average harvesting cost per forest assortment was estimated, based on the geographic and other properties of the area. Using cost structure and resource availability, marginal cost curves were constructed to allow analyses of the effects of changing market conditions and different policy frameworks. Based on geographically explicit data, the results indicated that the average harvesting costs would be 21–24 € m−3 for roundwood, depending on the type of harvesting and extraction operation. The corresponding cost estimate for harvesting residues was 23–25 € m−3 and 35 € m−3 for stumps. The harvesting cost estimates lie on the steeper part of the marginal cost curve, suggesting that increases in the supply of woody biomass can only occur at significantly higher harvesting costs. From a policy perspective, this suggests that subsidies aimed at reducing the harvesting costs will only have limited success in increasing the harvested volumes, given current technology. Therefore, for future development in the supply of forest assortments for energy generation, it is important to consider not only the supply potential, but also the integration of improvements in harvesting and transportation systems.
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| 48. |
- Mandova, Hana, et al.
(författare)
-
Achieving carbon-neutral iron and steelmaking in Europe through the deployment of bioenergy with carbon capture and storage
- 2019
-
Ingår i: Journal of Cleaner Production. - : Elsevier. - 0959-6526 .- 1879-1786. ; 218, s. 118-129
-
Tidskriftsartikel (refereegranskat)abstract
- The 30 integrated steel plants operating in the European Union (EU) are among the largest single-point CO 2 emitters in the region. The deployment of bioenergy with carbon capture and storage (bio-CCS) could significantly reduce their emission intensities. In detail, the results demonstrate that CO 2 emission reduction targets of up to 20% can be met entirely by biomass deployment. A slow CCS technology introduction on top of biomass deployment is expected, as the requirement for emission reduction increases further. Bio-CCS could then be a key technology, particularly in terms of meeting targets above 50%, with CO 2 avoidance costs ranging between €60 and €100 t CO2 −1 at full-scale deployment. The future of bio-CCS and its utilisation on a larger scale would therefore only be viable if such CO 2 avoidance cost were to become economically appealing. Small and medium plants in particular, would economically benefit from sharing CO 2 pipeline networks. CO 2 transport, however, makes a relatively small contribution to the total CO 2 avoidance cost. In the future, the role of bio-CCS in the European iron and steelmaking industry will also be influenced by non-economic conditions, such as regulations, public acceptance, realistic CO 2 storage capacity, and the progress of other mitigation technologies.
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| 49. |
- Mandova, Hana, et al.
(författare)
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Modelling bio-CCS deployment across iron and steel plants in Europe
- 2018
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Ingår i: GHGT 2018 - 14th International Conference on Greenhouse Gas Control Technologies. - : Elsevier.
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Konferensbidrag (refereegranskat)abstract
- Iron and steel production is highly reliant on coal, which makes integrated steel plants one of the largest single point CO2 emitters. Technologies that would significantly reduce their coal consumption are currently still at pilot scale. Hence opportunities for bioenergy and CCS as emission reduction strategies are evaluated, as they could be directly integrated within the existing iron and steelmaking setup. At the same time, their co-application – referred to as bio-CCS – can further enhance the emission reduction potential of each one of them. This can result in low-carbon steelmaking emitting over 80% less emissions in comparison to today, which would satisfy the EU targets set for 2050. This work gives an overview of modelling bio-CCS systems, specifically incorporated within the techno-economic BeWhere model, focusing on the deployment of bio-CCS across the integrated steel plants in Europe. The obtained results give an estimate of the average CO2 avoidance cost of 86 € tCO2-1, but high variation is present across the individually plants, ranging between 62 and 114 € tCO2-1. Overall, bio-CCS provides an opportunity to achieve net-zero CO2 emissions occurring on-site (when assuming carbon neutrality of biomass). Modelling possibilities for bio-CCS integration is complex, due to a sophisticated and unique setup of energy usage across each integrated plant together with multiple social-technical factors that may limit their CO2 transport and storage. Introduction of numerous assumptions is hence necessary to overcome those barriers, particularly related to issues on data availability.
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- Mandova, H., et al.
(författare)
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Possibilities for CO2 emission reduction using biomass in European integrated steel plants
- 2018
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 115, s. 231-243
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Tidskriftsartikel (refereegranskat)abstract
- Iron and steel plants producing steel via the blast furnace-basic oxygen furnace (BF-BOF) route constitute among the largest single point CO2 emitters within the European Union (EU). As the iron ore reduction process in the blast furnace is fully dependent on carbon mainly supplied by coal and coke, bioenergy is the only renewable that presents a possibility for their partial substitution. Using the BeWhere model, this work optimised the mobilization and use of biomass resources within the EU in order to identify the opportunities that bioenergy can bring to the 30 operating BF-BOF plants. The results demonstrate competition for the available biomass resources within existing industries and economically unappealing prices of the bio-based fuels. A carbon dioxide price of 60 € t−1 is required to substitute 20% of the CO2 emissions from the fossil fuels use, while a price of 140 € t−1 is needed to reach the maximum potential of 42%. The possibility to use organic wastes to produce hydrochar would not enhance the maximum emission reduction potential, but it would broaden the available feedstock during the low levels of substitution. The scope for bioenergy integration is different for each plant and so consideration of its deployment should be treated individually. Therefore, the EU-ETS (Emission Trading System) may not be the best policy tool for bioenergy as an emission reduction strategy for the iron and steel industry, as it does not differentiate between the opportunities across the different steel plants and creates additional costs for the already struggling European steel industry. © 2018 The Authors
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