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  • 1.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Perspectives on Demand Side Management1996Book (Other scientific)
    Abstract [en]

    This work treats recommendations based on energy systems engineering. The focus is on what can be learned by different methods about the roles that demand-side energy efficiency should play in the energy system. In the first part of the thesis, two case studies of local energy planning demonstrate the role of demand-side energy efficiency: energy systems engineering suggests a design in which energy efficiency improvements are aligned with the whole technical energy system. One result of the case studies is that the energy consumers invest in fewer energy efficiency measures than recommended by the methodologies applied. This indicates that there are important aspects of demand-side energy efficiency that are ignored by the methodologies used. In this work, the cause of the difference between the recommended and observed investments is addressed by an investigation of the customer's transaction cost for the energy efficiency investment. The second part is an application of the viable system model and focuses on the role of energy efficiency activities at a public energy utility. A case study demonstrates that most energy efficiency activities were run to support energy sales and, hence, were totally entwined with the traditional business. This role observed is compared with that suggested by the demand-side management methodology. The comparison shows that demand-side management is not capable of handling important aspects of interrelations between energy efficiency activities and energy sales. The work provides a language for further discussion of the role of energy efficiency activities at energy utilities.

  • 2.
    Björkqvist, Olof
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Fridén, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Concepts of Steam Recovery from LC-Refining by Increase Temperature2009In: Proceedings - 2009 International Mechanical Pulping Conference, IMPC 2009, 2009, p. 190-194Conference paper (Refereed)
    Abstract [en]

    In a mechanical pulping process, (TMP) wood is refined to pulp in a process with very high wood utilization. However, the power demand in the process is high. Thus efficient energy recovery, especially steam recov-ery, is very important. In high consistency (HC) refining the pulp wood is refined at high temperature (140°C) and pressure. The high temperature makes it possible to recover process heat with usable steam properties.

    One strategy to decrease the power consumption is to split the refining into two stages, one HC-stage and one low consistency (LC) refining stage. This kind of sys-tem is quite common today. One drawback with LC-refining is that it operates at a low temperature normally below 100°C. Hence, the steam recovery potential from conventional LC-refining is limited.

    In this project, we analyse three concepts of steam re-covery in LC-refining by increasing the temperature in the LC-stage. Two base cases: Conventional HC refin-ing only and conventional HC/LC refining is compared with three steam recovery cases: Pulp/Pulp heat ex-changing, Screw Press Dewatering combined with proc-ess water re-circulation and finally Pulp/Water Heat Exchanging.

    The study shows that it is possible to recover steam from the LC-stage and, hence, increase the energy effi-ciency of a combined HC/LC refining system. The screw press case has the highest steam recovery poten-tial of the HC/LC configurations. An initial economic estimate indicates that steam recovery in LC-refining is profitable compared to a conventional HC/LC-configuration.

  • 3.
    Björkqvist, Olof
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Fridén, Håkan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering and Sustainable Development.
    Energiåtervinning vid LC-raffinering – Förstudie2008Report (Other academic)
    Abstract [en]

    Normally, steam recovery from a conventional low consistency (LC) mechanical pulprefining system is not possible. This is due to the fact that the temperature level in theLC-refiner is less than 100°C. The steam with such a low temperature and associatedpressure has limited value in the mill. In this project, we study a concept of increasingthe temperature in the refiner to a level were process steam with higher quality can berecovered. The temperature level can be increased by transferring heat from outgoingpulp or drainage to incoming pulp or water. This makes it possible to recover heat fromthe process.An initial estimate indicates that steam recovery from LC-refining systems may have agood economic potential. Three cases have been analyzed: Case A: Steam recovery incombination with pulp/pulp heat exchanging, Case B: Steam recovery in combinationwith a pressurized screw press and finally Case C: steam recovery in combination withpump/water heat exchanging.Case B show the best specific steam recovery, 87% kWh recovered steam per kWh usedelectricity. This concept has a lower technological uncertainty compared to cases A andC as it does not need heat exchanging from pulp.The specific heat recovery from case A and C is 78% and 82% respectively. However,the suggested heat exchangers used in these cases do not exist on the market today.There is hence a need for development of exchangers that can handle pulp with highviscosity. The technological risk associated with the screw press scenario is lower and itis likely that this concept is easier to implement.

  • 4.
    Björkqvist, Olof
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Htun, Myat
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Norgren, Magnus
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    FORE – Ett nytt industrikombinat baserat på mekaniska massaprocesser2010In: Svensk papperstidning, Nordisk cellulosa, ISSN 1101-766X, no 2, p. 24-25Article in journal (Other (popular science, discussion, etc.))
  • 5.
    Björkqvist, Olof
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics.
    Idefeldt, Jim
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media.
    Risk Assessment of New Pricing Strategies in the District Heating Market: A Case Study at Sundsvall Energi AB2010In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 38, no 5, p. 2171-2178Article in journal (Refereed)
    Abstract [en]

    The price structure of district heating has been no major scientific issue for the last decades in energy related research. However, today trends in district heating pricing tend to move towards a more customer oriented approach with fixed prices under a longer period, leading to a more complex price structure. If a district heating supplier offers district heating with fixed prices in order to compete with similar electricity offers, the financial risk of the fixed price product is significantly higher than the risk of an ordinary variable cost offer. In contrary to an electricity seller, the district heating company can not transfer all of the risk of fixed prices offer to the financial market, instead the company is thrown upon its own ability to handle the risk by, e.g., hedging its own energy purchase. However, all uncertainties can not be coped with in this manner. Thus, there is a need for a methodology that can be used to estimate the financial risk of different price structures and to value different opportunities to reduce the risk. In this article we propose a methodology, implemented in a prototype software, to evaluate the risk associated with new price structures in district heating.

  • 6.
    Engstrand, Per O.
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Ferritsius, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Johansson, Lars
    PFI.
    Johansson, Örjan
    Luleå Tekniska Universitet.
    Daniel, Geoffrey
    Sveriges Lantbruks Universitet.
    Ferritsius, Rita
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Karlström, Anders
    Chalmers.
    Karlsson, Anette
    SCA Forest Products AB, Ortviken.
    Sandberg, Christer
    Holmen Paper, Braviken.
    Mekmassainitiativet för energieffektivitet, e2mp-i2015Report (Other academic)
    Abstract [sv]

    Projektet har drivits som ett program för finansiering av forskning som ska utveckla ochdemonstrera tekniker som reducerar elenergiförbrukningen med 50% vid tillverkning avTMP och CTMP med bibehållna slutproduktegenskaper hos tryckpapper och kartong.Programmet är en del av skogsindustrins initiativ att under en tioårsperiod tillsammansmed svenska och norska finansiärer investera minst 200 Mkr för att nå detta radikalaeffektiviseringsmål. Ett uttalat mål för industriinitiativet är också att befästaforskningsnoderna vid FSCN i Sundsvall och PFI i Trondheim.

    Parallellt med Energimyndighetens finansiering, 30 Mkr, har Norges Forskningsråd satsat25 MNOK (2010‐14) i industriinitiativet, KK‐stiftelsen 36 MSEK (2011‐17) ochMittuniversitetet har finansierat12 MSEK. Industrins totala satsning kommer att överstiga100 MSEK redan vid utgången av 2017.

    Resultat från benchmarkingstudien BAT2012 av industrins modernaste TMP‐ och CTMPlinjersamt från demonstrationsskaleprojekt visas i rapporten. Projekten baseras delvis pågrundläggande forskningsprojekt genomförda inom FSCN´s KK‐stiftelse‐finansieradeforskningsprofil och projektet ”Filling the Gap” 31676‐, ISSN 1650‐5387 2014:57. Resultaten visar följande reduktionsnivåer; 28% TMP för news (Braviken), 14% TMP för SC(Kvarnsveden) och 21% CTMP för kartong (Skoghall).

    Utöver demoprojekten finns ytterligare tydliga potentialer beskrivna i övriga delprojekt:

    Processintensifiering och processmodifiering > 15%

    Processtabilitet via avancerad processanalys och reglering > 15%

    Kombinera effektivaste processavsnitt från benchmarking ca 25%Detta gör det troligt att det kommer att gå att i fullskaliga demonstrationsförsök validera50% elenergireduktion inom de tre produktområdena, förutsatt att fortsattforskningsfinansiering finns tillgänglig. Tre av de idéer till avknoppningsprojekt somframkommit under projektets gång har redan erhållit beslut om finansiering frånEnergimyndigheten 2015. Ytterligare projektförslag baserade på den här redovisadeforskningen kommer att ingå i ansökningar under 2016. Utöver energireduktion i själva TMP‐ och CTMP‐processerna har forskare vid FSCN lagt forskningsgrunden för hur manska kunna tillverka mycket starka förpackningsmaterial från dessa massatyper på ettenergieffektivt sätt. Även inom detta område kommer en ansökning omuppskalningsprojekt att skickas in.

  • 7.
    Große, Christine
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Olausson, Pär M.
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Danielsson, Erna
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Wallman Lundåsen, Susanne
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Nyhlén, Jon
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Collaboration and Decision-making in Response Planning for Power Shortages: The Swedish Policy2017Conference paper (Other academic)
    Abstract [en]

    Electricity is a key resource for the majority of societal functions and constitutes an important sector in the critical infrastructure of modern societies. Disturbances in power supply can have cascading effects on interdependent public sectors and ordinary citizens. However, it seems nearly impossible to completely prevent the occurrence of power shortages. Strategies to address temporary power losses are therefore essential. This paper aims to increase the understanding of national policies to manage the early consequences of power outages. Therefore, we critically review the Swedish national policy called Styrel as part of Swedish Crisis Management System. In the scientific literature, there are few examples similar to Styrel for handling emergencies in the electricity system. Particularly, we seek to discover related risks and benefits, conditions and constraints, as well as effects for specific stakeholders. We argue that the approach cannot yet be considered as fully developed. Three areas requiring improvement are identified. First, the scope and terms of the process must be specified. Second, (better) quality management seems necessary. Third, people responsible for identifying and prioritizing power consumers critical to local society need better decision aid. Improvements could facilitate risk-communication and collaboration among actors as well as decision-making and organisational learning.

  • 8.
    He, Jie
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Zhang, Wennan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Techno-economic evaluation of a mechanical pulp mill with gasification2013In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 28, no 3, p. 349-357Article in journal (Refereed)
    Abstract [en]

    Mechanical pulping processes, including thermomechanical pulp (TMP), groundwood (SGW andPGW), and chemithermomechanical pulp (CTMP) processes, each have a very high wood-to-pulp yield. Producing pulp by means of these processes is a prerequisite for paper (such as printing paper and paperboard) grades requiring high printability and stiffness. However, mechanical pulping processes consume a great amount of electricity, which may account for up to 40% of the total pulp production cost.

    In mechanical pulping mills, wood (biomass) residues are commonly utilized for electricity production through an associated combined heat and power (CHP) plant. This techno-economic evaluation deals with the possibility of utilizing a biomass integrated gasification combined cycle (BIGCC) plant in place of the CHP plant.

    Implementing BIGCC in a mechanical pulp production line might greatly improve the overall energy efficiency and cost-effectiveness, especially when more biomass from forest (such as branches and tree tops) is available. When the fibre material that negatively affects pulp properties is utilized as a bioenergy resource, the overall efficiency will be further improved. A TMP+BIGCC mathematical model is developed with ASPEN Plus. By means of modeling, three cases are studied:

    1) adding more forest biomass logging residues in the gasifier,2) adding the reject fibres in the gasifier, and3) decreasing the TMP-specific electricity consumption (SEC) by up to 50%.

    For a TMP+BIGCC mill, the energy supply and consumption are analyzed in comparison with a TMP+CHP mill. The production profits are evaluated.

  • 9.
    Hedlund, Alexander
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering. FrontWay AB.
    Stengard, Anna-Karin
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering. Sundsvall Energi AB.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    A simulation-based method for evaluation of energy system cooperation between pulp and paper mills and a district heating system: A case study2017In: 19 World academy of science, engineering and technology conference proceedings, 2017, Vol. 19, p. 1158-1164Conference paper (Refereed)
    Abstract [en]

    A step towards reducing greenhouse gases and energy consumption is to collaborate with the energy system between several industries. This work is based on a case study on integration of pulp and paper mills with a district heating system in Sundsvall, Sweden. 

    Present research shows that it is possible to make a significant reduction in the electricity demand in the mechanical pulping process. However, the profitability of the efficiency measures could be an issue, as the excess steam recovered from the refiners decreases with the electricity consumption. A consequence will be that the fuel demand for steam production will increase. If the fuel price is similar to the electricity price it would reduce the profit of such a project. If the paper mill can be integrated with a district heating system, it is possible to upgrade excess heat from a nearby kraft pulp mill to process steam via the district heating system in order to avoid the additional fuel need. The concept is investigated by using a simulation model describing both the mass and energy balance as well as the operating margin. Three scenarios were analyzed: reference, electricity reduction and energy substitution. The simulation show that the total input to the system is lowest in the Energy substitution scenario. Additionally, in the Energy substitution scenario the steam from the incineration boiler covers not only the steam shortage but also a part of the steam produced using the biofuel boiler, the cooling tower connected to the incineration boiler is no longer needed and the excess heat can cover the whole district heating load during the whole year. 

    The study shows a substantial economic advantage if all stakeholders act together as one system. However, costs and benefits are unequally shared between the actors. This means that there is a need for new business models in order to share the system costs and benefits. 

  • 10.
    Norgren, Robert
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Fröling, Morgan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Industrial Symbiosis solutions for recycling of biosludge from the pulp industry2015In: Proceedings of Global Cleaner Production & Sustainable Consumption Conference  1 - 4 November 2015, Sitges, Barcelona, Spain, 2015Conference paper (Other academic)
    Abstract [en]

    Bio sludge is a waste that is produced in large amounts at the pulp and paper industry waste water treatment. It is wet and has no obvious advantages, therefore few recycling methods are in praxis but focus is on disposal. Common disposal methods are incineration and composting. In Sweden and Norway about half of the sludge is incinerated, but in Finland almost all of it is incinerated. Landfilling of the sludge is common in Chile where half the sludge is landfilled and the other half is incinerated.

    Efficient use of material and energy is crucial for future more sustainable industry practices. This is true for primary products and commercial available energy but also for material that today is regarded as waste. The pulp and paper industry is subjected to a shift in consumer behavior initiated by modern information technology that results in lower demand for newspapers. In the future there are reasons to expect increased competition from new producers in countries where the productivity of the forests are higher and thereby the production costs is lower. These two aspects forces the pulp and paper industry in the Scandinavian countries to optimize the efficiency of their mills and to seek revenues from new types of products.

    Biomass waste in general could be recycled for its energy content or after conversion/extraction as a chemical product or a solid material. Different forces like legislation, market demand and scientific innovations exert a push or pull towards different paths of recycling. They may either cooperate or counteract each other and the sum of their impact may favor one of these paths.

    Some possible paths of recycling inspired by industrial symbiosis will be presented and the maturity of these technologies assessed. The sludge’s content of heavy metals have been compared to limit values in Swedish national regulation and standards.

    The content of metals in the sludge exceed some of the current limit values and could in a greater extent exceed the future limit values if they will be lower than today. Therefore direct application of the sludge can only be a short term solution.

    Most treatment methods produce either a liquid or solid residue and the metals could be concentrated in any of these so the metals in the residue must be assessed regardless of what technology is used. To maximize the usefulness of the sludge it is essential to assume that the problem with the metals can be solved.

    Production of bricks and glass stabilizes the metals but the resources are then locked in a matrix which make them to a lesser extent available for use.

    The production of SCP and a lead adsorber are two alternatives that is regarded both circular and relative mature. These two should be assessed according to the LCA-method together with incineration combined with improved dewatering.

  • 11.
    Norgren, Robert
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Fröling, Morgan
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Sustainable Building Engineering.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Pulp mill bio-sludge - sludge properties and recycling2016In: Proceedings of 5th International Conference on Industrial & Hazardous Waste Management, September 27th-30th, 2016, Chania, Kreta., 2016Conference paper (Other academic)
    Abstract [en]

    Bio sludge is a waste that is produced in large amounts at the waste water treatment plants at the pulp and paper industry. It is wet and has no obvious economic advantages, therefore present industrial focus is not on recycling methods but on disposal. Common disposal methods are incineration and composting. In Sweden and Norway about half of the sludge is incinerated, the other half is composted in Finland almost all is incinerated whereas landfilling of the sludge is common in Chile where half the sludge is landfilled and the other half is incinerated.

    Biomass waste in general could be recycled for its energy content or as a resource for chemical products or solid materials. Different forces like legislation, market demand and scientific innovations will exert push or pull towards different potential paths of recycling. To choose a recycling method for a sludge from a specific pulp mill one must consider the properties of the sludge. These properties depends on the type of tree species used (hard wood or soft wood), amount of extractive substances, type of process the pulp mills use (mechanical pulp or Kraft), reject handling and the configuration of the water treatment plant. It could be that one single recycling method is not the optimal one for all pulp mills.

    In this study, a comparison of bio-sludge properties between different Swedish pulp mills was investigated and its impact on the recyclability assessed. Ten mills were chosen that were expected to represent the extremes or unique combinations of raw material, type of cooking process, bleaching etc., and at the same time were easy to distinguish from each other. The samples were analysed for their content of possible useful substrates like lignin, fat or protein. Also the content of heavy metals were analysed, they could be problematic when handling rejects from the recycling process. Totally 21 parameters were analysed.

    The potential relationship between types of processes, raw material, chemicals used etc. and sludge properties and its recyclability were assessed. Potential recycling methods found in the scientific literature was screened and evaluated for technology readiness level, environmental aspects, the potential market value and profitability for production of sludge derived benefits was estimated.

    The two complementing perspectives mentioned above, sludge properties and appropriateness of technology were combined with the goal to suggest suitable recycling methods for the different sludge qualities that are produced today.

  • 12.
    Norgren, Robert
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Suistainable Building Engineering. Ragn-Sells AB, Timrå, Sweden.
    Jonsson, Anders
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Ecotechnology and Suistainable Building Engineering.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Bio-sludge from the pulp and paper industry as feed for black soldier fly larvae: A study of critical factors for growth and survival2019In: Waste and Biomass Valorization, ISSN 1877-2641, E-ISSN 1877-265XArticle in journal (Refereed)
    Abstract [en]

    Pulp and paper bio-sludge (PPBS) has low economic value and is therefore often composted or incinerated. The purpose of this work is to evaluate the feasibility of using PPBS to breed black soldier fly (Hermetia illucens) larvae (BSFL), so improving resource efficiency and supplying protein and fat to the animal feed market. BSFL were reared on PPBS in a climate chamber on a laboratory scale in order to assess nutrient deficiency, inhibition and whether the BSFL recycle the PPBS well or not. The PPBS used came from a chemi-thermomechanical pulp/groundwood pulp mill. The effect of supplementing nutrient solution added either into the PPBS or as a free liquid surface were studied. Prepupae dry weight, survival rate until prepupae stage and residual dry PPBS were measured. The addition of reference diet leachate into the PPBS did not have a significant impact on the weight of the prepupae (2.0 mg) but the survival rate was significantly higher (16.0 %). On the other hand, the addition of reference diet leachate as a free liquid surface had a significant impact on both the weight of the prepupae (4.8 mg) and the survival rate (25.7 %). The bio – conversion and PPBS – reduction was as best 0.4 % and 3.2 % respectively. This study has proven that the nutrients in PPBS are not readily available to the larvae. Addition of reference diet leachate increase the survival rate which opens up for possibilities of co-digestion. However, it is clear that under the tested conditions, BSFL is not recycling PPBS well and BSFL as a method for recycling of PPBS need further research.

  • 13.
    Olausson, Pär M.
    et al.
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences. Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering. Mid Sweden University, Faculty of Science, Technology and Media, Department of Natural Sciences, Engineering and Mathematics. Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Danielsson, Erna
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences. Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Große, Christine
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Larsson, Aron
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Information and Communication systems. Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Technology and Media. Mid Sweden University, Faculty of Science, Technology and Media, Department of Information Systems and Technology.
    Nyhlén, Jon
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences. Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Wallman Lundåsen, Susanne
    Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences. Mid Sweden University, Faculty of Human Sciences, Department of Social Sciences.
    Från myndighet till medborgare och tillbaka: En studie av samverkan och kommunikation inomramen för STYREL2018Report (Other (popular science, discussion, etc.))
    Abstract [en]

    STYREL is a planning process aiming at ensuring electricity supply to sociallyimportant objects during a situation of power shortage. The fact that STYREL is animportant planning process with great importance for securing the electricitysupply to important users of electricity is an opinion all the interviewees express.At the same time, there is also a consensus that the process is in need ofdevelopment and change in order to achieve the aims behind the process.The empirical study included documents, investigations, 65 interviews,participatory observation and participation in meetings and network meetingswithin the framework of the planning process. The critical review shows that thereare several areas of improvement to consider that could increase the quality andreduce the risk of important social functions becoming without electricity during aperiod of power shortage. The areas that are particularly highlighted in the studyconcern the necessity of integrating recurring feedback into the planning system,creating networks at both local and regional level to ensure that private-sector orimportant civil society actors is excluded and finally, further clarify the varioussteps and the different roles in the planning system. This can be achievedcomparing with international planning systems on critical infrastructure and withnational planning systems within the crisis management systems.

  • 14.
    Wärja, Mathias
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    A Systems Approach to Maintenance and Renewal Strategies2005In: CIRED 2005, 2005Conference paper (Other academic)
  • 15.
    Wärja, Mathias
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Reliability Based Approach to Maintenance and Renewal Strategies2004In: Proceedings of PowerCon 2004, 2004Conference paper (Other academic)
  • 16.
    Wärja, Mathias
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Engineering, Physics and Mathematics.
    Variety Reduction Model for Maintenance and Renewal Strategies2004In: Proceedings of NORDAC 2004, 2004Conference paper (Other academic)
  • 17.
    Zhang, Wennan
    et al.
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    He, Jie
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Engstrand, Per
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Björkqvist, Olof
    Mid Sweden University, Faculty of Science, Technology and Media, Department of Chemical Engineering.
    Economic evaluation on bio-synthetic natural gas production integrated in a thermomechanical pulp mill2015In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 8, no 11, p. 12795-12809Article in journal (Refereed)
    Abstract [en]

    In this study, biorefinery as a concept is applied to thermomechanical pulp (TMP)-based paper production to evaluate the possibility of co-production of synthetic natural gas (SNG), electricity and district heating in addition to mechanical pulp and paper. The combined heat and power plant (CHP) associated to TMP is replaced by a biomass-to-SNG (BtSNG) plant. Implementing BtSNG in a mechanical pulp production line might improve the profitability of a TMP mill and also help to commercialize the BtSNG technology by taking into account of some key issues such as biomass availability, heat utilization, etc. A TMP + BtSNG mathematical model is developed with ASPEN Plus. The model prediction shows that the scale of the TMP + BtSNG mill and SNG price are two strong factors for the implementation of BtSNG in a TMP mill. A BtSNG plant associated to a TMP mill should be built at a scale above 100 MW of biomass thermal input. For the case of Swedish economic condition, commercialization of SNG production as a transport biofuel has not matured yet. Political instruments to support commercialization of transport biofuel are necessary.

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