| 1. |
- Xiros, Charilaos, 1973, et al.
(författare)
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Toward a sustainable biorefinery using high-gravity technology
- 2017
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Ingår i: Biofuels, Bioproducts and Biorefining. - : Wiley. - 1932-1031 .- 1932-104X. ; 11:1, s. 15-27
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Tidskriftsartikel (refereegranskat)abstract
- The realization of process solutions for a sustainable bioeconomy depends on the efficient processing of biomass. High-gravity technology is one important alternative to realizing such solutions. The aims of this work were to expand the knowledge-base on lignocellulosic bioconversion processes at high solids content, to advance the current technologies for production of second-generation liquid biofuels, to evaluate the environmental impact of the proposed process by using life cycle assessment (LCA), and to develop and present a technically, economically, and environmentally sound process at high gravity, i.e., a process operating at the highest possible concentrations of raw material. The results and opinions presented here are the result of a Nordic collaborative study within the framework of the HG Biofuels project. Processes with bioethanol or biobutanol as target products were studied using wheat straw and spruce as interesting Nordic raw materials. During the project, the main scientific, economic, and technical challenges of such a process were identified. Integrated solutions to these challenges were proposed and tested experimentally, using wheat straw and spruce wood at a dry matter content of 30% (w/w) as model substrates. The LCA performed revealed the environmental impact of each of the process steps, highlighting the importance of the enzyme dose used for the hydrolysis of the plant biomass, as well as the importance of the fermentation yield.
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| 2. |
- Ahlgren, Serina, et al.
(författare)
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Review of methodological choices in LCA of biorefinery systems - key issues and recommendations
- 2015
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Ingår i: Biofuels, Bioproducts and Biorefining. - : Wiley. - 1932-1031 .- 1932-104X. ; 9:5, s. 606-619
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Forskningsöversikt (refereegranskat)abstract
- The current trend in biomass conversion technologies is toward more efficient utilization of biomass feedstock in multiproduct biorefineries. Many life-cycle assessment (LCA) studies of biorefinery systems have been performed but differ in how they use the LCA methodology. Based on a review of existing LCA standards and guidelines, this paper provides recommendations on how to handle key methodological issues when performing LCA studies of biorefinery systems. Six key issues were identified: (i) goal definition, (ii) functional unit, (iii) allocation of biorefinery outputs, (iv) allocation of biomass feedstock, (v) land use, and (vi) biogenic carbon and timing of emissions. Many of the standards and guidelines reviewed here provide only general methodological recommendations. Some make more specific methodological recommendations, but these often differ between standards. In this paper we present some clarifications (e.g. examples of research questions and suitable functional units) and methodological recommendations (e.g. on allocation).
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| 3. |
- Janssen, Mathias, 1973, et al.
(författare)
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Life cycle assessment of lignin-based carbon fibres
- 2019
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Ingår i: 14th Conference on sustainable development of energy, water and environment systems.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Lignin-based carbon fibres may replace both glass fibres and fossil-based carbon fibres. The objective of this study was to determine the environmental impact of the production of lignin-based carbon fibres using life cycle assessment. The life cycle assessment was done from cradle to gate and followed an attributional approach. The climate impact per kg of lignin- based carbon fibres produced was 1.50 kg CO2,eq. In comparison to glass fibres, the climate impact was reduced by 32% and the climate impact of fossil-based carbon fibres was an order of magnitude higher. A prospective analysis, in which the background energy system was cleaner, showed that the environmental impact of lignin-based carbon fibres will decrease and outperform the glass fibres and fossil-based carbon fibres from a climate impact point-of-view. The constructed LCA model can be applied in further studies of products that consist of or use lignin-based carbon fibres.
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| 4. |
- Janssen, Mathias, 1973, et al.
(författare)
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Life cycle impacts of ethanol production from spruce wood chips under high gravity conditions
- 2016
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Ingår i: Biotechnology for Biofuels. - : Springer Science and Business Media LLC. - 1754-6834 .- 1754-6834. ; 9:1, s. 53-
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Tidskriftsartikel (refereegranskat)abstract
- BackgroundDevelopment of more sustainable biofuel production processes is ongoing, and technology to run these processes at a high dry matter content, also called high-gravity conditions, is one option. This paper presents the results of a life cycle assessment (LCA) of such a technology currently in development for the production of bio-ethanol from spruce wood chips.ResultsThe cradle-to-gate LCA used lab results from a set of 30 experiments (or process configurations) in which the main process variable was the detoxification strategy applied to the pretreated feedstock material. The results of the assessment show that a process configuration, in which washing of the pretreated slurry is the detoxification strategy, leads to the lowest environmental impact of the process. Enzyme production and use are the main contributors to the environmental impact in all process configurations, and strategies to significantly reduce this contribution are enzyme recycling and on-site enzyme production. Furthermore, a strong linear correlation between the ethanol yield of a configuration and its environmental impact is demonstrated, and the selected environmental impacts show a very strong cross-correlation (r^2 > 0.9 in all cases) which may be used to reduce the number of impact categories considered from four to one (in this case, global warming potential). Lastly, a comparison with results of an LCA of ethanol production under high-gravity conditions using wheat straw shows that the environmental performance does not significantly differ when using spruce wood chips. For this comparison, it is shown that eutrophication potential also needs to be considered due to the fertilizer use in wheat cultivation.ConclusionsThe LCA points out the environmental hotspots in the ethanol production process, and thus provides input to the further development of the high-gravity technology. Reducing the number of impact categories based only on cross-correlations should be done with caution. Knowledge of the analyzed system provides further input to the choice of impact categories.
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| 5. |
- Arvidsson, Rickard, 1984, et al.
(författare)
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Energy use and climate change improvements of Li/S batteries based on life cycle assessment
- 2018
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Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 383, s. 87-92
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Tidskriftsartikel (refereegranskat)abstract
- We present a life cycle assessment (LCA) study of a lithium/sulfur (Li/S) cell regarding its energy use (in electricity equivalents, kWhel) and climate change (in kg carbon dioxide equivalents, CO2 eq) with the aim of identifying improvement potentials. Possible improvements are illustrated by departing from a base case of Li/S battery design, electricity from coal power, and heat from natural gas. In the base case, energy use is calculated at 580 kWhel kWh−1 and climate change impact at 230 kg CO2 eq kWh−1 of storage capacity. The main contribution to energy use comes from the LiTFSI electrolyte salt production and the main contribution to climate change is electricity use during the cell production stage. By (i) reducing cell production electricity requirement, (ii) sourcing electricity and heat from renewable sources, (iii) improving the specific energy of the Li/S cell, and (iv) switching to carbon black for the cathode, energy use and climate change impact can be reduced by 54 and 93%, respectively. For climate change, our best-case result of 17 kg CO2 eq kWh−1 is of similar magnitude as the best-case literature results for lithium-ion batteries (LIBs). The lithium metal requirement of Li/S batteries and LIBs are also of similar magnitude.
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| 6. |
- Arvidsson, Rickard, 1984, et al.
(författare)
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Environmental Assessment of Emerging Technologies: Recommendations for Prospective LCA
- 2018
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Ingår i: Journal of Industrial Ecology. - : Wiley. - 1530-9290 .- 1088-1980. ; 22:6, s. 1286-1294
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Forskningsöversikt (refereegranskat)abstract
- The challenge of assessing emerging technologies with life cycle assessment (LCA) has been increasingly discussed in the LCA field. In this article, we propose a definition of prospective LCA: An LCA is prospective when the (emerging) technology studied is in an early phase of development (e.g., small-scale production), but the technology is modeled at a future, more-developed phase (e.g., large-scale production). Methodological choices in prospective LCA must be adapted to reflect this goal of assessing environmental impacts of emerging technologies, which deviates from the typical goals of conventional LCA studies. The aim of the article is to provide a number of recommendations for how to conduct such prospective assessments in a relevant manner. The recommendations are based on a detailed review of selected prospective LCA case studies, mainly from the areas of nanomaterials, biomaterials, and energy technologies. We find that it is important to include technology alternatives that are relevant for the future in prospective LCA studies. Predictive scenarios and scenario ranges are two general approaches to prospective inventory modeling of both foreground and background systems. Many different data sources are available for prospective modeling of the foreground system: scientific articles; patents; expert interviews; unpublished experimental data; and process modeling. However, we caution against temporal mismatches between foreground and background systems, and recommend that foreground and background system impacts be reported separately in order to increase the usefulness of the results in other prospective studies.
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| 7. |
- Arvidsson, Rickard, 1984, et al.
(författare)
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Potential improvements of the life cycle environmental impacts of a Li/S battery cell
- 2018
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The lithium sulfur (Li/S) battery is a promising battery chemistry for two reasons: it requires no scarce metals apart from the lithium itself and it brings the promise of high specific energy density at the cell level. However, the environmental impacts of this battery type remain largely unstudied. In this study, we conducted a life cycle assessment (LCA) of the production of an Li/S cell to calculate these impacts. The anode consists of a lithium foil and the cathode consists of a carbon/sulfur composite. The electrolyte is a mixture of dioxalane, dimethoxyethane, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and lithium nitrate. The current collector for the cathode is an aluminium foil and a tri-layer membrane of polypropylene and polyethylene acts as separator. The functional unit of the study is 1 kWh specific energy storage. Three key environmental impacts were considered: energy use, climate change and lithium requirement. In our baseline scenario, we consider the pilot-scale production of a battery with a specific energy of 300 kWh/kg, having the mesoporous material CMK-3 as carbon material in the carbon/sulfur cathode, and using coal power and natural gas heat as energy sources. This scenario results in an energy use of 580 kWh/kWhstored and a climate change impact of 230 kg CO2eq/kWhstored. The main contributor to energy use is the LiTFSI production and the main contributor to climate change is electricity use during cell production. We then model a number of possible improvements sequentially: (1) reduction of cell production electricity requirement due to production at industrial-scale, (2) sourcing of electricity and heat from renewable instead of fossil sources (i.e. solar power and biogas heat), (3) improvement of the specific energy of the Li/S cell to 500 kWh/kg and (4) a shift of the carbon material in the cathode to carbon black (without considering changes in performance). By implementing all these four improvements, energy use and climate change impact can be reduced by an impressive 54 and 93%, respectively. In particular, the improvements related to industrial-scale production and sourcing of renewable energy are considerable, whereas the shift of carbon material is of minor importance. For climate change, the best-case result of 17 kg CO2eq/kWhstored is similar to the best-case results reported in the scientific literature for lithium-ion batteries (LIBs). Regarding lithium requirement, the lithium metal requirement of Li/S batteries and LIBs are also of similar magnitude (0.33-0.55 kg/kWhstored and 0.2 kg/kWhstored, respectively). Using different allocation approaches did not alter the main conclusions of the study.
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| 8. |
- Arvidsson, Rickard, 1984, et al.
(författare)
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Prospective inventory modelling of emerging chemicals: The case of photonic materials
- 2019
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Ingår i: Abstracts book (SETAC Europe Annual Meeting). - 2310-3043 .- 2309-8031. ; 29, s. 96-
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Prospective life cycle assessment (LCA), or ex-ante LCA, has been defined as an assessment of a product system modeled at a future time, before its commercialization. Such assessments bring the promise of altering emerging technologies in a more environmentally benefitial direction before they become difficult to change. Since the future cannot be known with certainty, prospective modeling need to rely on scenarios of various kinds. However, how to conduct such prospective scenario modeling in practice still has to be clarified. In this study, we have modeled two emerging chemicals that can be used for a technology called photon upconversion, which converts low-energy light into higher-energy light harvestable by solar photovoltaics, thereby increasing their efficiency. Two chemicals currently considered for this purpose are ruthenium bipyridine chloride (RBC) and diphenylanthracene (DPA). These novel, emerging chemicals have not been studied regarding environmental performance before and are consequently not present in any LCA databases. The aim of this study is to present a generic procedure for prospective inventory modeling of emerging chemicals and apply that to the cases of RBC and DPA by developing unit processes for these two chemicals. An industrial synthesis scenario was adopted as our main scenario, reflecting a possible future time when RBC and DPA are produced at an industrial scale. The modeling was conducted in six steps: (1) Identify likely chemical syntheses. (2) Calculate inputs stoichiometrically based on the chemical synthesis reactions. (3) Modify inputs based on available yields for reactants and solvents (e.g. obtained from patents or estimated). (4) Categorize outputs as by-products or waste depending on their likely subsequent fate. (5)Calculate process emissions. (6) Model energy flows. Unit processes for the two emerging chemicals are thusly developed. The procedure is considered particularly strong for estimating inputs and output materials related to the stoichiometric reaction, but weaker regarding the estimation of emissions and energy requrement. Further research into the modeling of energy flows for high-temperature processes is therefore recommended, as well as estimation procedures for emissions from emerging chemicals production.
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| 9. |
- Aryapratama, Rio, et al.
(författare)
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Prospective life cycle assessment of bio-based adipic acid production from forest residues
- 2017
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Ingår i: Journal of Cleaner Production. - : Elsevier BV. - 0959-6526. ; 164, s. 434-443
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Environmental concerns related to the production of bulk chemicals are growing. Researchers and technology developers are currently looking into alternative production pathways for such chemicals by utilizing renewable resources, such as lignocellulosic feedstocks. Adipic acid is an example of such a bulk chemical, and its conventional fossil-based production emits significant amounts of N2O, a major greenhouse gas. In this study, a prospective life cycle assessment (LCA) of bio-based adipic acid production from forest residues at an early development stage, situated in Sweden, was conducted. Acid-catalyzed (using SO2) and alkaline (using NaBH4) pretreatment were employed and scenarios and sensitivity analyses were conducted. The potential environmental impacts of this technology under development were compared to those of conventional adipic acid production. The results show that bio-based adipic acid production has a lower impact on global warming, eutrophication and photochemical ozone creation compared to fossil-based production. In contrast, it has a higher impact on acidification. An increased efficiency of mitigating \{N2O\} emissions from the fossil-based production may alter this comparison. Producing bio-based adipic acid using the alkaline pretreatment has a higher environmental impact than producing it using acid-catalyzed pretreatment. Furthermore, if biomass is used to fulfil process energy demands, instead of fossil fuel, the environmental impact of the bio-based production decreases. It is therefore important to reduce the amount of NaBH4 used in the alkaline pretreatment or to lower the environmental impact of its production.
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| 10. |
- Badr, Sara, 1985, et al.
(författare)
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Combined basic and fine chemical biorefinery concepts with integration of processes at different technology readiness levels
- 2018
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Ingår i: Computer Aided Chemical Engineering. - 1570-7946. ; , s. 1577-1582
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Biorefineries offer promising alternatives to the use of fossil fuels to produce energy and chemicals. This work describes the development of a biorefinery concept to produce adipic acid from Swedish forest residues and lutein from micro-algae. A description is provided for each process line available, its technology readiness level (TRL) and the tools available to model it. Scenarios of the integrated concept are built with associated material flow analysis. Key results of the material inventory of the base case scenario are presented as well as insights into the development of further scenarios. Material flow inventories can then be further used for economic and environmental assessment. Major challenges of integration are discussed in terms of uncertainties and data gaps for processes with low TRL such as scaling up lab experiments, understanding the restrictions of material recycling and its impact on process performance. The feedback given through these scenarios can help guide further experimental efforts.
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