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Andersson, J., Ahlström, J., Berg, K., Olsson, H., Karlsson, L.-E., Niinipuu, M. & Pizzul, L. (2024). Biologisk metanisering av syngas från förgasning och pyrolys - lovande koncept mot implementering. RISE Research Institutes of Sweden
Åpne denne publikasjonen i ny fane eller vindu >>Biologisk metanisering av syngas från förgasning och pyrolys - lovande koncept mot implementering
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2024 (svensk)Rapport (Annet vitenskapelig)
Abstract [en]

Biological methanation of syngas from pyrolysis and gasification – promising concepts for implementation The need for increased biogas production is significant, and in the EU, there are plans for a substantial expansion in the coming years through the RePowerEU initiative. Part of the increase will come from the expansion of conventional digestion technology, where organic materials such as food waste, manure, and crop residues are used for biogas production. However, to meet the future increased demand, it is also necessary to utilize more difficult-to-digest substrates, such as biomass rich in lignocellulose, for biogas production. This could be forest residues such as branches and tops, sawdust, or bark. This type of substrates cannot be used in a conventional digestion process, and other technology chains are therefore required to convert such biomass into biomethane. This can be done by first converting the biomass into syngas through a thermochemical process such as gasification or pyrolysis. This is followed by a methanation process where the syngas is converted into biogas, and finally, the gas is upgraded to reach biomethane quality. These types of technology chains are not currently available on a commercial scale, but they have been demonstrated, for example, through the Gobigas project, where gasification was followed by catalytic methanation for biomethane production. As full-scale implementation of catalytic methanation of bio-syngas has not yet been achieved, thereis a need to develop alternative conversion technologies that can more cost-effectively achieve the methanation of woody biomass. One possible opportunity for to this is to apply biological methanation instead of a catalytic process. A biological process comes with several advantages, including a greater ability to handle contaminants, higher selectivity in the conversion of syngas, and operation at relatively low temperature and pressure, which simplifies material selection and reactor design. RISE, together with its partners, are developing a concept based on biological methanation of syngas. This project has examined the biological process's ability to handle contaminants in syngas through continuous experiments in carrier-filled trickle bed reactors with an active volume of 5 liters. The process's ability to handle and break down contaminants is an important parameter that can affect and simplify the design of the gas cleaning that occurs after gasification or pyrolysis. Another aspect of the project has been to put the experimental results into context at the concept and system level. Different production techniques for syngas have been mapped out, which could be combined with biological methanation. Based on the mapping, three types of plants have been selected for more detailed analyses of techno-economics, carbon footprint, and opportunities for increased carbon efficiency. The methanation experiments lasted for 552 days, and overall, it was a stable process with high turnover of syngas and high methane production over a long time. There have been some operational disturbances, mainly related to the supply of gas to the process (i.e. delivery of gas cylinders). However, biochemical inhibition or disturbances have been rare, demonstrating a high robustness for biological methanation of syngas. The breakdown of contaminants has been excellent in the process, with levels decreasing below the detection limit. At the same time, as contaminants have been continuously added to the process, microbiology has been able to maintain high turnover of hydrogen and carbon monoxide to methane. The specific methane production was high both during the reference period without contaminants and during the experimental periods with added contaminants. During long periods, the specific methane production has been around 4 L CH4/Lbed volume /day, which is about 4 times higher than our previously achieved results. The transition to thermophilic temperature and using carriers with higher effective surface area has contributed to this increase. During the project, three types of plants have been selected for more detailed analysis: 1) Gasification with Cortus process, which generates a relatively clean syngas with minimal purification needs before biological methanation. There is no need for co-location with a heating plant, but it is an advantage if there is access to the district heating network to sell waste heat. 2) Gasification with Bioshares' concept, where the gasifier is integrated into a larger cogeneration plant and where the produced syngas is purified with an RME-scrubber before biological methanation. Co-location with a larger cogeneration plant provides interesting synergies and integration opportunities, but also sets the boundaries for where the plants can be located. 3) Slow pyrolysis according to Envigas' concept, where the primary product is biochar and where the produced syngas is seen as a by-product. The syngas contains some impurities but generally requires no other purification than cooling to the right temperature (condensing out tars) before being added to biological methanation. This type of plant differs from plant types 1-2 in that the syngas formed is not the primary product, and the syngas has a relatively low energy value compared to the others. Syngas from plant types 2 and 3 contains some hydrocarbons (C1-C3) that are considered inert over the methanation step and therefore do not negatively affect the process. This means that heavier hydrocarbons do not need to be removed upstream, which would likely have been required with catalytic methanation. This leads to a higher system efficiency, and the need for reactor capacity for biological methanation decreases since there is less gas to be processed (more of the end-product consists of hydrocarbons already formed during the thermochemical conversion upstream). For all plant types, downstream of the methanation step, there is a need for further gas purification and upgrading. During the upgrading step carbon dioxide is separated to reach the product specification required by the end user. If long distance distribution is required a final process step consisting of a liquefaction plant for the production of liquid biogas (LBG) can be added to the concept. As another option, the systems can be supplemented with treatment of the carbon dioxide flow out of the upgrading plant, where the flow is processed by drying, compression, and cooling to produce liquid carbon dioxide. For plant type 2, where benzene is present in the syngas, this gas is expected to be separated with relatively high precision in the system and thereby generate a small flow of liquid benzene as a side product. The carbon dioxide emissions for the final product LBG are in the range of 1.6 to 2.6 gCO2-eq/MJLBG, which compares favorably to other types of second-generation biofuels. Compared to fossil gas, the reduction in greenhouse gas emissions is 96-97%. The carbon efficiency of the systems can be significantly increased if excess carbon dioxide is utilized either through BECCS or BECCU. If the carbon dioxide stream from the upgrading plant is processed into liquid carbon dioxide, the production cost is estimated to be 187-204 SEK/ton. If the product is to be sent to permanent storage the cost for transportation and storage would need to be added to estimate total cost of BECCS, but this is out of scope for the current project.. Assuming that BECCS is applied and that the entire carbon sink is allocated to the final product LBG, this will result in negative emissions in the range of -35 to -104 gCO2-eq/MJLBG. An alternative is to utilize excess carbon dioxide directly in the methanation process by boosting incoming gas with extra hydrogen. Hydrogen and carbon dioxide are then converted by methanogens, which generates extra methane. Since the addition of extra hydrogen is assumed to come from electrolysis, the additional methane production can likely be classified as electrofuel, so-called e-methane. The techno-economic evaluation results in a production cost ranging from 740 to 1300 SEK/MWhLBG, including all sensitivity scenarios. The lower price scenarios include a lower investment cost, which can be assumed to represent cases with public investment support. Overall, a large part of the scenarios are considered to be within the range of what can be considered market relevant production costs. This leads to the conclusion that there is techno-economic potential at this stage to justify continued development of concepts based on biological methanation of syngas. With scaling up and continued development in the right direction, the concepts may eventually lead to cost-effective utilization of forest residues for the production of biomethane at a commercially relevant scale. The next step in the development is scaling up to pilot scale, which will take place during 2023-2025 through an EU-funded project and will be carried out by RISE, Wärtsilä, Cortus and Swedish Gas Association. A pilot plant for biological methanation will then be operated with syngas from Cortus' gasifier in Höganäs.

sted, utgiver, år, opplag, sider
RISE Research Institutes of Sweden, 2024. s. 63
Serie
RISE Rapport ; 2024:26
Emneord
Biogas, Biomethane, Biological methanation, Methantion, SNG, LBG, Gasification, Pyrolysis
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-72468 (URN)978-91-89896-78-9 (ISBN)
Forskningsfinansiär
Swedish Energy Agency, 51438-1
Merknad

Projektet har finansierats av deltagande partners och Energimyndigheten (projektnummer 51438-1).

Tilgjengelig fra: 2024-04-08 Laget: 2024-04-08 Sist oppdatert: 2024-05-22bibliografisk kontrollert
Hansson, J., Ahlström, J., Furusjö, E., Lundgren, J. & Nojpanya, P. (2023). COSTS FOR REDUCING GHG EMISSIONS FROM ROAD AND AIR TRANSPORT WITH BIOFUELS AND ELECTROFUELS. In: European Biomass Conference and Exhibition Proceedings: . Paper presented at 31st European Biomass Conference and Exhibition, EUBCE 2023. Bologna, Italy. 5 June 2023 through 8 June 2023 (pp. 368-372). ETA-Florence Renewable Energies
Åpne denne publikasjonen i ny fane eller vindu >>COSTS FOR REDUCING GHG EMISSIONS FROM ROAD AND AIR TRANSPORT WITH BIOFUELS AND ELECTROFUELS
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2023 (engelsk)Inngår i: European Biomass Conference and Exhibition Proceedings, ETA-Florence Renewable Energies , 2023, s. 368-372Konferansepaper, Publicerat paper (Fagfellevurdert)
Abstract [en]

The potential future role of different biofuels, hydrogen, and so-called electrofuels/power-to-X (produced by electricity, water, and carbon dioxide, CO2) in different transportation sectors remains uncertain. The CO2 abatement cost, i.e., the cost for reducing a certain amount of greenhouse gas (GHG) emissions, is central from a societal and business perspective, the latter specifically in the case of an emission reduction obligation system (like in Germany and Sweden). The abatement cost of a specific fuel value chain depends on the production cost and the GHG reduction provided by the fuel. This paper analyses the CO2 abatement costs for different types of biofuels, biomass-based jet fuels and electrofuels for road transport and aviation, relevant for the Swedish and EU context. Since most assessed alternative fuel pathways achieve substantial GHG emission reduction compared to fossil fuels, the fuel production cost is, in general, more important to achieve a low CO2 abatement cost. The estimated CO2 abatement cost ranges from -0.37 to 4.03 SEK/kgCO2 equivalent. Fuels based on waste feedstock, have a relatively low CO2 abatement cost. Fuel pathways based on electricity or electricity and biomass have relatively high CO2 abatement cost. The CO2 abatement cost for lignocellulosic based pathways generally ends up in between. 

sted, utgiver, år, opplag, sider
ETA-Florence Renewable Energies, 2023
Emneord
Biofuels; Cost benefit analysis; Cost reduction; Emission control; Forestry; Fossil fuels; Gas emissions; Greenhouse gases; Roads and streets; Abatement costs; Aviation fuel; Forest residue; Greenhouse gas; Greenhouse gas emissions; Greenhouses gas; Power; Power-to-x; Production cost; Road transports; Carbon dioxide
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-68048 (URN)2-s2.0-85174598141 (Scopus ID)
Konferanse
31st European Biomass Conference and Exhibition, EUBCE 2023. Bologna, Italy. 5 June 2023 through 8 June 2023
Tilgjengelig fra: 2023-11-23 Laget: 2023-11-23 Sist oppdatert: 2023-11-23bibliografisk kontrollert
Zavalis, T., Ström, M., Persson, D., Wendel, E., Ahlström, J., Törne, K., . . . Tidblad, J. (2023). Mechanistic Model with Empirical Pitting Onset Approach for Detailed and Efficient Virtual Analysis of Atmospheric Bimetallic Corrosion. Materials, 16(3), Article ID 923.
Åpne denne publikasjonen i ny fane eller vindu >>Mechanistic Model with Empirical Pitting Onset Approach for Detailed and Efficient Virtual Analysis of Atmospheric Bimetallic Corrosion
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2023 (engelsk)Inngår i: Materials, E-ISSN 1996-1944, Vol. 16, nr 3, artikkel-id 923Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

A mechanistic model of atmospheric bimetallic corrosion with a simplified empirical approach to the onset of localized corrosion attacks is presented. The model was built for a typical bimetallic sample containing aluminum alloy 1050 and stainless steel 316L sheets. A strategy was developed that allowed the model to be calibrated against the measured galvanic current, geometrical corrosion attack properties, and corrosion products. The pitting-onset simplification sets all pits to be formed at a position near the nobler metal and treated all pits as being of the same shape and size. The position was based on the location of the highest pitting events and the pit attributes on an average of the deepest pits. For 5 h exposure at controlled RH (85%, 91%, and 97%) and salt load (86 μg NaCl/cm2), the model was shown to be promising: both for analysis of local bimetallic corrosion chemistry, such as pH and corrosion products, and for efficient assessment of pitting damage by computing a single largest pit depth. Parametric studies indicated that the pitting-onset approximation deviated the most at the beginning of exposure and when RH was below 91%. © 2023 by the authors.

sted, utgiver, år, opplag, sider
MDPI, 2023
Emneord
AA 1050, aluminum, bimetallic corrosion, galvanic corrosion, lightweight, modeling, pitting, simulation, stainless steel, Aluminum alloys, Aluminum corrosion, Atmospheric chemistry, Atmospheric corrosion, Damage detection, Sodium chloride, Steel corrosion, Corrosion attack, Corrosion products, Mechanistic models, Pittings
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-64101 (URN)10.3390/ma16030923 (DOI)2-s2.0-85147850777 (Scopus ID)
Merknad

Correspondence Address: Zavalis Tommy, RISE Research Institutes of Sweden, Sweden; email: tommy.zavalis@ri.se; Funding details: VINNOVA, 2018-0288; Funding text 1: This work was funded by LIGHTer, a strategic innovation program within the Swedish innovation agency (VINNOVA) grant number 2018-0288.

Tilgjengelig fra: 2023-02-28 Laget: 2023-02-28 Sist oppdatert: 2024-04-04bibliografisk kontrollert
Ahlström, J., Jafri, Y., Wetterlund, E. & Furusjö, E. (2023). Sustainable aviation fuels – Options for negative emissions and high carbon efficiency. International Journal of Greenhouse Gas Control, 125, Article ID 103886.
Åpne denne publikasjonen i ny fane eller vindu >>Sustainable aviation fuels – Options for negative emissions and high carbon efficiency
2023 (engelsk)Inngår i: International Journal of Greenhouse Gas Control, ISSN 1750-5836, E-ISSN 1878-0148, Vol. 125, artikkel-id 103886Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

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)

sted, utgiver, år, opplag, sider
Elsevier Ltd, 2023
Emneord
Biofuels, Carbon dioxide, Carbon footprint, Cost benefit analysis, Cost reduction, Feedstocks, Forestry, Greenhouse gases, Aviation fuel, Bio-energy, Carbon efficiency, Climate impacts, Climate targets, Combusting fuels, Fuel option, GHG reductions, High carbons, Storage energy, Carbon capture, bioenergy, biofuel, carbon, carbon storage, efficiency measurement, emission, fuel consumption, sustainability, Cost Control, Efficiency, Operating Costs, Processes, Reduction
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-64392 (URN)10.1016/j.ijggc.2023.103886 (DOI)2-s2.0-85152301363 (Scopus ID)
Merknad

 Correspondence Address: Ahlström, J.; RISE Research Institutes of Sweden, Stockholm, Sweden; email: johan.m.ahlstrom@ri.se

Tilgjengelig fra: 2023-05-03 Laget: 2023-05-03 Sist oppdatert: 2023-05-23bibliografisk kontrollert
Jafri, Y., Ahlström, J., Furusjö, E., Harvey, S., Pettersson, K., Svensson, E. & Wetterlund, E. (2022). Double Yields and Negative Emissions?: Resource, Climate and Cost Efficiencies in Biofuels With Carbon Capture, Storage and Utilization. Frontiers in Energy Research, 10, Article ID 797529.
Åpne denne publikasjonen i ny fane eller vindu >>Double Yields and Negative Emissions?: Resource, Climate and Cost Efficiencies in Biofuels With Carbon Capture, Storage and Utilization
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2022 (engelsk)Inngår i: Frontiers in Energy Research, E-ISSN 2296-598X, Vol. 10, artikkel-id 797529Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

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.

sted, utgiver, år, opplag, sider
Frontiers Media S.A., 2022
Emneord
BECCS, BECCU, bio-CCS, biofuels, carbon capture, carbon utilization, GHG footprint, negative emissions, Carbon footprint, Competition, Cost effectiveness, Cost reduction, Fossil fuels, Greenhouse gases, Biofuel production, Biogenics, GHG reductions, Negative emission, Resource efficiencies, Carbon dioxide
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-60609 (URN)10.3389/fenrg.2022.797529 (DOI)2-s2.0-85128342022 (Scopus ID)
Merknad

Funding details: Energimyndigheten; Funding text 1: This study is the result of a project carried out within the collaborative research program Renewable transportation fuels and systems (förnybara drivmedel och system), Project no. [P48363-1]. The project has been financed by the Swedish Energy Agency and f3-Swedish Centre for Renewable Transportation Fuels. Economic support from Bio4Energy, a strategic research environment appointed by the Swedish government, is also gratefully acknowledged.

Tilgjengelig fra: 2022-10-14 Laget: 2022-10-14 Sist oppdatert: 2023-05-23bibliografisk kontrollert
Lundblad, A. O., Nordin Fürdös, A., Nilsson, K., Pettersson, K., Axelsson, L. & Ahlström, J. (2022). Vätgas som alternativ för skogsindustrins transporter– en jämförande studie (H2Timmer).
Åpne denne publikasjonen i ny fane eller vindu >>Vätgas som alternativ för skogsindustrins transporter– en jämförande studie (H2Timmer)
Vise andre…
2022 (svensk)Rapport (Annet vitenskapelig)
Abstract [sv]

Detta förstudieprojekt har visat att vätgasdrift för timmerlastbilar ger något högre men ändå liknande kilometerkostnad som ren batteridrift, men snabbare tankning och längre körsträcka, vilket ger större flexibilitet för åkaren. Även biodrivmedel kan vara ett konkurrenskraftigt alternativ. Skogsindustrin är en av Sveriges största transportanvändare. För timmertransporter är lastbil det klart viktigaste transportslaget och skogsindustrins transporter motsvarar ca 17 % av Sveriges transporterade gods på väg. Ett alternativ för omställning av skogsindustrins transporter till fossilfrihet är förnybar vätgas, som kan produceras genom elektrolys med förnybar el. Precis som el ger vätgas inte upphov till några lokala emissioner vid användningen. Produktion av vätgas kan potentiellt ha synergier för skogsindustrins massabruk, som behov av syrgas och tillgång till överskottsel. Projektet har undersökt vätgas som alternativ för skogsindustrins transporter. Hela värdekedjan, inklusive produktion, komprimering, lagring, och användning inkluderas i analysen som beaktar kostnader, energieffektivitet och växthusgasutsläpp ur ett ”well-to wheel”-perspektiv. Studien inkluderar jämförelser med andra möjliga alternativ för att ställa om transporterna till fossilfrihet så som elektrifiering och biodrivmedel. Projektet har gett resultat som kommer att ligga till grund för en mer detaljerad projekteringsstudie inför ett framtida demonstrations- och pilotprojekt. Studien som finansierats av Trafikverket genom TripleF har genomförts av RISE tillsammans med 6 skogsindustribolag, tre företag från fordonsbranschen och två systemintegratörer med fokus på vätgas. Medverkande företag och organisationer: Sveaskog, SmurfitKappa, Metsä Group, Holmen, StoraEnso, BillerudKorsnäs, AB Volvo, Volvo Penta, Volvo CE, Nilsson Energy, Euromekanik, Energiforsk, Skogsindustrierna.

Publisher
s. 129
Serie
Triple F
Emneord
Vätgas, elektrolys, bränslecell, timmertransport, fossilfri, arbetsmaskiner, tankstation
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-59199 (URN)
Tilgjengelig fra: 2022-05-17 Laget: 2022-05-17 Sist oppdatert: 2023-05-23
Lundblad, A. O., Nordin Fürdös, A., Persson, K., Pettersson, K., Axelsson, L. & Ahlström, J. (2022). Vätgas som alternativ för skogsindustrins transporter– en jämförande studie (H2Timmer): Exekutiv sammanfattning.
Åpne denne publikasjonen i ny fane eller vindu >>Vätgas som alternativ för skogsindustrins transporter– en jämförande studie (H2Timmer): Exekutiv sammanfattning
Vise andre…
2022 (svensk)Rapport (Annet vitenskapelig)
Abstract [sv]

Detta förstudieprojekt har undersökt vätgas som alternativ för skogsindustrins transporter. Hela värdekedjan, inklusive produktion, komprimering, lagring, och användning inkluderas i analysen som beaktar kostnader, energieffektivitet och växthusgasutsläpp ur ett ”well-to wheel”-perspektiv. Projektet har genomförts av RISE tillsammans med följande företag och organisationer: Sveaskog, SmurfitKappa, Metsä Group, Holmen, StoraEnso, BillerudKorsnäs, AB Volvo, Volvo Penta, Volvo CE, Nilsson Energy, Euromekanik, Energiforsk, Skogsindustrierna.

Publisher
s. 5
Serie
Triple F
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-59200 (URN)
Tilgjengelig fra: 2022-05-17 Laget: 2022-05-17 Sist oppdatert: 2023-05-23bibliografisk kontrollert
Ahlström, J., Tidblad, J., Tang, L., Sederholm, B. & Leijonmarck, S. (2018). Electrochemical properties of oxide scale on steel exposed in saturated calcium hydroxide solutions with or without chlorides. International Journal of Corrosion, 2018, Article ID 5623504.
Åpne denne publikasjonen i ny fane eller vindu >>Electrochemical properties of oxide scale on steel exposed in saturated calcium hydroxide solutions with or without chlorides
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2018 (engelsk)Inngår i: International Journal of Corrosion, ISSN 1687-9325, E-ISSN 1687-9333, Vol. 2018, artikkel-id 5623504Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

The electrochemical properties of various iron oxide scales on steel exposed in saturated calcium hydroxide solutions were investigated. The iron oxide scales were manufactured by different heat treatments and grinding processes and characterized using X-ray diffraction and scanning electron microscope. The electrochemical properties of the scales were assessed by measuring the corrosion potential and using electrochemical impedance spectroscopy and potentiodynamic polarization curves. It was found that wustite and magnetite are less noble compared to hematite but are more effective as cathodic surfaces. The results show that the electrochemical properties of the mill scale can be an important contributing factor in the corrosion of steel in concrete.

Emneord
Chlorine compounds, Electrochemical corrosion, Electrochemical impedance spectroscopy, Electrochemical properties, Hematite, Hydrated lime, Lime, Magnetite, Scale (deposits), Scanning electron microscopy, Calcium hydroxide solution, Cathodic surfaces, Contributing factor, Corrosion of steel in concretes, Corrosion potentials, Grinding process, Iron oxide scale, Potentiodynamic polarization curves, Steel corrosion
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-36784 (URN)10.1155/2018/5623504 (DOI)2-s2.0-85056572728 (Scopus ID)
Tilgjengelig fra: 2018-12-21 Laget: 2018-12-21 Sist oppdatert: 2023-05-22bibliografisk kontrollert
Sederholm, B., Trägårdh, J., Ahlström, J., Boubitsas, D. & Luping, T. (2018). Ny provningsmetodik för bestämning av bindemedlets korrosionsskyddande förmåga i betong.
Åpne denne publikasjonen i ny fane eller vindu >>Ny provningsmetodik för bestämning av bindemedlets korrosionsskyddande förmåga i betong
Vise andre…
2018 (svensk)Rapport (Annet vitenskapelig)
Abstract [sv]

Denna rapport omfattar slutrapporteringen av forskningsprojektet - Ny provningsmetodik för bedömning av bindemedlets korrosionsskyddande förmåga i betong – Underlag till LCA och livslängdsbedömning. I rapporten redovisas resultat från elektrokemiska undersökningar utförda på laboratorium och korrosionsprovningar i fält. Undersökningarna har genomförts av Swerea KIMAB, RISE CBI Betonginstitutet (väst och öst) samt Chalmers. Projektets mål har varit att genom en nationell samling av expertis ta fram en ny provningsmetodik som på ett enkelt och tillämpbart sätt ska utvärdera olika bindemedels korrosionsskyddande förmåga i betong. I denna undersökning har framför allt tiden till initiering av korrosion (gropfrätning) från det att kloriderna har nått stålytan och tills gropfrätning har initieras på stålytan undersökts. Tre olika accelererade elektrokemiska mätmetoder har använts och jämförts:

 Potentiostatisk mätmetod

 Potentiodynamisk mätmetod

 Galvanostatisk mätmetod

Den framtagna provningsmetodiken med framställning av provkroppar har visat sig fungera väl. För att minska spridningen är det emellertid viktigt att använda en homogen och rengjord stålyta utan glödskal. Glödskalet avlägsnas lämpligast genom slipning eftersom betning kan bygga upp ett passivskikt på stålytan. För att undvika att betongrester fastnar på stålytan ska släta provstänger användas.

Sammanfattningsvis kan sägas att resultaten från laboratorie- och fältmätningarna samt analyser av bindemedlens korrosionskänslighet genom TG- och XRD-analyser visade att denna kombination av mätningar ger ett bra verktyg att bedöma den korrosionsskyddande förmågan hos olika bindemedel. En sammanställning av rangordningen för bindemedlens korrosionsskyddande förmåga redovisas i tabellen nedan.

Den korrosionsskyddande förmågan hos de undersökta bindemedlen rangordnas från en sammanvägning av de olika provningsmetoderna:

 bra < 1,5 och

 1,5 ≥mindre bra ≤2,5 och

 dåligt > 2,5.

Som rangordningen visar i tabellen så har bindemedel med slagg och portlandcement med hög C 3A en bra korrosionsskyddande förmåga. Detta beror till största delen på kapaciteten att bilda Friedels salt från monosulfat under härdningsprocessen. Bindemedel som har en låg korrosionsskyddande förmåga har ett lågt C3A-innehåll och en inblandning av flygaska och/eller silika. Det medför dessutom en utspädningseffekt på förmågan att bilda Friedels salt.

Publisher
s. 43
Serie
Swerea KIMAB  Research reports ; KIMAB 2018-162
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-38334 (URN)
Prosjekter
Ny provningsmetodik för bedömning av bindemedlets korrosionsskyddande förmåga i betong – Underlag till LCA och livslängdsbedömning, projektnummer:12401
Forskningsfinansiär
Swedish Transport AdministrationSBUF - Sveriges Byggindustriers Utvecklingsfond
Merknad

Denna rapport omfattar slutrapporteringen av forskningsprojektet - Ny provningsmetodik för bedömning av bindemedlets korrosionsskyddande förmåga i betong – Underlag till LCA och livslängdsbedömning. Projektet har till största del finansierats av Trafikverkets branschprogram för forskning och innovation avseende byggnadsverk för transportsektorn (BBT) och Svenska Byggbranschens utvecklingsfond (SBUF). Övriga finansiärer har varit Stiftelsen för Cement och Betonginstitutets A-forskning och Swerea KIMAB. Projektet påbörjades i juni 2014 och avslutas i september 2018.

Tilgjengelig fra: 2019-04-18 Laget: 2019-04-18 Sist oppdatert: 2023-05-22bibliografisk kontrollert
Ahlström, J., Pettersson, K., Wetterlund, E. & Harvey, S. (2017). Value chains for integrated production of liquefied bio-SNG at sawmill sites – Techno-economic and carbon footprint evaluation. Applied Energy, 206, 1590-1608
Åpne denne publikasjonen i ny fane eller vindu >>Value chains for integrated production of liquefied bio-SNG at sawmill sites – Techno-economic and carbon footprint evaluation
2017 (engelsk)Inngår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 206, s. 1590-1608Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

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.

Emneord
Gasification, Liquefied bio-SNG, Process integration, Sawmill, System analysis, Value chain, Biomass, Chains, Costs, Feedstocks, Fuels, Investments, Liquefied natural gas, Sawing, Sawmills, Systems analysis, Wood products, Biomass transportations, Carbon footprint reductions, Efficient use of energy, Integrated production, Transportation cost, Value chains, Carbon footprint
HSV kategori
Identifikatorer
urn:nbn:se:ri:diva-32803 (URN)10.1016/j.apenergy.2017.09.104 (DOI)2-s2.0-85029745260 (Scopus ID)
Tilgjengelig fra: 2017-12-01 Laget: 2017-12-01 Sist oppdatert: 2023-05-23bibliografisk kontrollert
Organisasjoner
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0001-9130-2925
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