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  • 1.
    Lundmark, Robert
    et al.
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    Wetterlund, Elisabeth
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Lundgren, Joakim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Ouraich, Ismail
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    Bryngemark, Elina
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    Zetterholm, Jonas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Olofsson, Elias
    Nolander, Carl
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    Pettersson, Karin
    Chalmers tekniska högskola, Sverige.
    Harvey, Simon
    Chalmers tekniska högskola, Sverige.
    Ahlström, Johan
    Chalmers tekniska högskola.
    Andersson, Stefan
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    Projekt: En hållbar omställning av energisystemet mot en ökad andel bioenergi2016Övrigt (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    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.

  • 2.
    Wang, Chuan
    et al.
    Swerea MEFOS, Box 812, Luleå.
    Zetterholm, Jonas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Lundqvist, Magnus
    Swerea MEFOS, Box 812, Luleå.
    Schlimbach, Jürgen
    DK Recycling und Roheisen GmbH.
    Modelling and Analysis of Oxygen Enrichment to Hot Stoves2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 5128-5133Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper presents some research work on applying the oxygen enrichment technique to hot stoves that was carried out in one European RFCS project. In the presented work, both theoretical and practical work was studied. A dynamic model was used to investigate the effects of oxygen enrichment on hot stoves’ performance under the condition that only blast furnace gas was used as the fuel gas. The modelling results showed that SOE will enhance the combustion process in hot stoves by increasing hot blast temperature and shortening the on-gas time, which were further verified by industrial trials performed at an iron-making plant. In addition, CFD modelling was performed by simulating different oxygen levels and lance positions at the burner to avoid the hot spot formation during the combustion.

  • 3.
    Zetterholm, Jonas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Forest based biorefinery supply chains - Identification and evaluation of economic, CO2, and resource efficiency2018Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Biorefineries for production of fuels, chemicals, or materials, can bean important contribution to reach a fossil-free economy. Large-scaleforest-based biorefineries are not yet cost competitive with their fossil counterparts and it is important to identify biorefinery supply chain configurations with good economic, CO2, and biomass performance if biorefineries are to be a viable alternative to the fossil refineries.

    Several factors influence the performance of biorefinery supply chains,e.g. type of conversion process, geographical localisation, and produc-tion capacity. These aspects needs to be analysed in conjunction to identify biorefineries with good supply chain performance. There ares everal approaches to improve the performance of biorefineries, wheree.g. integration with other industries can improve the economic perfor-mance by utilisation of excess heat and by-products. From a Swedish perspective the traditional forest industry is of interest as potential host industries, due to factors such as by-product availability, opportunity for heat integration, proximity to other biomass resources, and their experience in operating large-scale biomass supply chains.

    The objectives of this work were to investigate how different supply chain configurations influence the economic, biomass, and CO2 perfor-mance of thermochemical biorefineries integrated with forest industries,as well as methods for evaluating those supply chains.

    This work shows that there is an economic benefit for integration with the traditional forest industry for thermochemical biorefineries.This is especially true when the biorefinery concept can replace cur-rent old industrial equipment on site which can significantly improvethe economic performance of the biorefinery, highlighting the role the Swedish forest industry could play to reach a cost efficient large-scale implementation of lignocellulosic biorefineries.

    The cost for biomass is a large contributor to the total cost of biore-fineries and for traditional techno-economic evaluations, the biomass prices are considered as static variables. A large-scale biorefinery will likely have an impact on the biomass market, which could lead to both changes in the biomass price, as well as changed biomass demand for other industries. A framework where this is accounted for was intro-duced, combining a techno-economic perspective for evaluating the sup-ply chain performance, with a market model which identifies changes in biomass price and allocation due to the increased biomass competition.

    The biorefinery performance can be determined from several per-spectives and system boundaries, both from a plant-level and a national perspective. To facilitate a large-scale introduction of biorefineries and  maximise the benefit from their implementations, there is a need to identify biorefinery concepts with high performance considering severa system boundaries, which has been explored in this work.

  • 4.
    Zetterholm, Jonas
    et al.
    Department of Process Integration, Swerea MEFOS AB.
    Ji, Xiaoyan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Sundelin, Bo
    SSAB EMEA Oxelösund.
    Martin, Peter M.
    Siemens VAI Metals Technologies.
    Wang, Chuan
    Swerea MEFOS AB, Center for Process Integration in Steelmaking, Swerea MEFOS, Luleå.
    Model Development of a Blast Furnace Stove2015Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 75, s. 1758-1765Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A large amount of energy is required in the production of steel where the preheating of blast in the hot blast stoves for iron-making is one of the most energy-intensive processes. To improve the energy efficiency it is necessary to investigate how to improve the hot blast stove operation.In this work a mathematic model for evaluating the performance of the hot blast stove was developed using a finite difference approximation to represent the heat transfer inside the stove during operation. The developed model was calibrated by using the process data from the stove V26 at SSAB Oxelösund, Sweden. As a case study, the developed model was used to simulate the effect of a new concept of OxyFuel technique to hot blast stoves. The investigation shows that,by using the OxyFuel technique, it is possible to maintain the blast temperature while removing the usage of coke oven gas. Additionally, the hot blast temperature increases while the flue gas temperature decreases, which allows for an increase of the blast temperature, leading to improved energy efficiency for the hot stove system.

  • 5.
    Zetterholm, Jonas
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Ji, Xiaoyan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Sundelin, Bo
    SSAB EMEA Oxelösund , SSAB Special Steels Oxelösund.
    Martin, P.M.
    Siemens VAI Metals Technologies, United States.
    Wang, C.
    Department of Process Integration, Swerea MEFOS AB.
    Dynamic modelling for the hot blast stove2017Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 185, nr 2, s. 2142-2150Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A large amount of energy is required in the production of steel where the preheating of blast in the hot blast stoves for iron-making is one of the most energy-intensive processes. To improve the energy efficiency of the steelmaking it is necessary to investigate how to improve the hot blast stove operation.In this work a mathematic model for evaluating the performance of the hot blast stove was developed using a finite difference approximation for the heat transfer inside the stove during operation. The developed model was calibrated and validated by using the process data from hot blast stove V26 at SSABs plant in Oxelösund, Sweden. The investigation shows a good agreement between the measured and modelled data.As a case study, the developed model was used to simulate the effect of a new concept of OxyFuel technique to hot blast stoves. The investigation shows that, by using this OxyFuel technique, it is possible to maintain the blast temperature while removing the usage of coke oven gas (COG). The saved COG can be used to replace some fossil fuel, such as oil and LPG.Furthermore, the effect of the cycle time on the single stove was studied. As expected, both the hot blast and flue gas temperatures are increased when increasing the cycle time. This shows that it is a good strategy for the hot blast stove to increase the blast temperature if the stove is currently not operated with the maximum allowed flue-gas temperature. 

  • 6.
    Zetterholm, Jonas
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Mossberg, Johanna
    RISE Research Institutes of Sweden, Bioeconomy.
    Joakim, Lundgren
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wetterlund, Elisabeth
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Evaluating investments in integrated biofuel production - factoring in uncertainty through real options analysis2019Ingår i: PROCEEDINGS OF ECOS 2019 / [ed] Wojciech Stanek, Paweł Gładysz, Sebastian Werle, Wojciech Adamczyk, 2019, s. 1921-1932Konferensbidrag (Refereegranskat)
    Abstract [en]

    In the endeavour to reduce CO2 emissions from the transport sector, biofuels from forest industry by-products are key. The adaptation of forest-based biorefinery technologies has so far been low which can partly be attributed to uncertainties in the form of policy instability, market prices, and technology costs. These uncertainties in combination with technology learning, which can be expected to reduce future investment costs, could make it favourable to postpone an investment decision. When applying real options theory, it is recognised that there is an opportunity cost associated with the decision to invest, since the option to wait for more favourable market conditions to occur is forfeited. In traditional discounted cash flow analysis, the impact of uncertainty and the value of reducing it (e.g. by waiting), is usually not taken into consideration. This paper uses a real options framework that incorporates the option to postpone an investment to reduce market uncertainties and wait for technology learning to occur. The focus is to investigate how the usage of an investment decision rule based on real options analysis affects technology choice, the economic performance, and when in time it is favourable to invest in pulp mill integrated biofuel production, compared with using a decision rule based on traditional discounted cash flow analysis. As an illustrative case study we examine a pulp mill which has the option, but not the obligation, to invest in either of two different biofuel production technologies that both use the pulp mill by-product black liquor as feedstock: (1) black liquor gasification followed by fuel synthesis, and (2) membrane separation of lignin followed by hydrodeoxygenation. With the usage of the real options framework and the inclusion of the uncertainties regarding future market prices and investment costs, the decision to invest is made later, compared with using traditional cash flow analysis. The usage of real options also reduces the likeliness of a net loss occurring if an investment is made, as well as increases the expected economic returns, showing the added economic value of flexibility in the face of uncertain future conditions.

  • 7.
    Zetterholm, Jonas
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Pettersson, Karin
    RISE Research Institutes of Sweden, Eklandagatan 86, SE-412 61 Gothenburg.
    Leduc, Sylvain
    International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, A-2361 Laxenburg.
    Lundgren, Joakim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap. International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, A-2361 Laxenburg.
    Wetterlund, Elisabeth
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap. International Institute for Applied Systems Analysis (IIASA), Schlossplatz 1, A-2361 Laxenburg.
    Resource efficiency or economy of scale: Biorefinery supply chain configurations for co-gasification of black liquor and pyrolysis liquids2018Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 230, s. 912-924Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Biorefineries for the production of fuels, chemicals, or materials can be an important contributor to reducing dependence on fossil fuels. The economic performance of the biorefinery supply chain can be increased by, for example, industrial integration to utilise excess heat and products, increasing size to improve economy of scale, and using intermediate upgrading to reduce feedstock transport cost. To enable a large-scale introduction of biorefineries it is important to identify cost efficient supply chain configurations.

    This work investigates a lignocellulosic biorefinery concept integrated with forest industry, focusing on how different economic conditions affect the preferred supply chain configurations. The technology investigated is black liquor gasification, with and without the addition of pyrolysis liquids to increase production capacity. Primarily, it analyses trade-offs between high biomass conversion efficiency and economy of scale effects, as well as the selection of centralised vs. decentralised supply chain configurations.

    The results show the economic advantage for biomass efficient configurations, when the biorefinery investment is benefited from an alternative investment credit due to the replacement of current capital-intensive equipment at the host industry. However, the investment credit received heavily influenced the cost of the biorefinery and clearly illustrates the benefit for industrial integration to reduce the cost of biorefineries. There is a benefit for a decentralised supply chain configuration under very high biomass competition. However, for lower biomass competition, site-specific conditions will impact the favourability of either centralised or decentralised supply chain configurations.

  • 8.
    Zetterholm, Jonas
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wetterlund, Elisabeth
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Pettersson, Karin
    SP/Energi och bioekonomi/Energi- och miljösystemanalys.
    Lundgren, Joakim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Evaluation of co-gasification of black liquor and pyrolysis liquids from a national systems perspective2016Ingår i: Meeting Sweden's current and future energy challenges, Luleå: Luleå tekniska universitet, 2016, Luleå: Luleå tekniska universitet, 2016Konferensbidrag (Övrigt vetenskapligt)
  • 9.
    Zetterholm, Jonas
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wetterlund, Elisabeth
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap. International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria.
    Pettersson, Karin
    RISE Research Institutes of Sweden, Eklandagatan 86, Göteborg, Sweden.
    Lundgren, Joakim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap. International Institute for Applied Systems Analysis (IIASA), Laxenburg, Austria.
    Evaluation of value chain configurations for fast pyrolysis of lignocellulosic biomass: Integration, feedstock, and product choice2018Ingår i: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 144, s. 564-575Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fast pyrolysis of lignocellulosic biomass constitutes a promising technology to reduce dependence on fossil fuels. The product, pyrolysis liquids, can either substitute heavy fuel oil directly, or be upgraded via e.g. hydroprocessing to diesel and petrol. This study presents a systematic evaluation of production costs and CO2 mitigation potentials of different fast pyrolysis value chain configurations. The evaluation considers types of localisations, emissions from electricity and hydrogen production, biomass feedstocks, and final products. The resulting production costs were found to be in the range of 36–60 EUR/MWh for crude pyrolysis liquids, and 61–90 EUR/MWh upgraded to diesel and petrol. Industrial integration was found to be favoured. The CO2 mitigation potential for the pyrolysis liquids was in the range of 187–282 t-CO2/GWh biomass. High variations were found when upgraded to diesel and petrol –best-case scenario resulted in a mitigation of 347 t-CO2/GWh biomass, while worst-case scenarios resulted in net CO2 emissions. Favourable policy support, continued technology development, and/or increased fossil fuel prices are required for the technology to be adapted on an industrial scale. It was concluded that integration with existing industrial infrastructure can contribute to cost reductions and thus help enable the transformation of traditional forest industry into biorefineries.

1 - 9 av 9
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