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  • 1.
    Arthur, Rohan
    et al.
    Department of Chemical Engineering, Monash University.
    Nguyen, Jeffery H.
    Department of Chemical Engineering, Monash University.
    Truong, T.
    Department of Chemical Engineering, Monash University.
    Wagstaff, Kiri L.
    Department of Chemical Engineering, Monash University.
    Wielechowski, Daniel P.
    Department of Chemical Engineering, Monash University.
    Wong, M.
    Department of Chemical Engineering, Monash University.
    Hoadley, Andrew F.A.
    Department of Chemical Engineering, Monash University.
    Garnier, Gil I.L.
    Department of Chemical Engineering, Monash University.
    Stenvall, Jonas
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Optimising the production cost of urea from black liquor2014Ingår i: Pulp & paper, bioenergy, bioproducts: Fibre Value Chain Conference & Expo 2014, October 15 - 17, 2014, Distinction Hotel Rotorua, New Zealand ; conference proceedings ; [including abstracts of the 5th Advanced Biofuels Research Network symposium (ABRN)], Bundoora: Appita Inc , 2014, s. 91-95Konferensbidrag (Refereegranskat)
    Abstract [en]

    A conceptual design of an integrated facility for the co-production of ammonia and electricity from black liquor gasification has been studied. The integrated process exchanges black and green liquor, steam, electricity and sulfur with the adjacent Kraft pulp mill. A triple bottom line analysis has indicated that a competitive ammonia price (A$516/t) can be realized for a relatively small scale production 20ktpa of NH3 with an internal rate of return of 13.7%. This is achieved through a novel process design which also produces electricity and steam for the pulp mill. The plant has a carbon footprint at 50% of the average and 33% below world best practice for NH3. Social benefits are also predicted for the regional community.

  • 2.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Rationell elanvändning genom värmeackumulering1987Rapport (Övrigt vetenskapligt)
  • 3.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Short term water heat storage: experimental study of temperatures and velocities1989Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
  • 4.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Short term water heat storage: studies of velocity and temperature fields and their importance for sizing of the storage1993Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Short term water heat storage's have been introduced in many district heating systems. The main reason for this is the possibilities opened by the storage for optimization of the generation of heat and electricity in combined heat and power plants. The basic task for the storage is then to bridge the timevise gap between the heat demand and supply of heat from a cogeneration plant. Water heat storage's can also be useful in district heating systems supplied with industrial waste heat. The water volume in the storage must be stratified to avoid degradation of the quality of the heat that has been charged. Experimental studies of phenomena that influence the stratification and cause a degradation of the quality has been made in model storage's of different sizes The studies include extensive temperature measurements and velocity measurements with different techniques. Laser Doppler Anemometry was used to measure the vertical velocities in the boundary layer at the outer walls. The gradient zone was found to have a strong impact on the velocity field. The maximum velocity in the boundary layer was increasing due to available height up to a certain level where it remained constant. Particle Image Velocimetry Technique were used for measuring the two dimensional velocity field in seeded water in a plane illuminated by a laser. These measurements showed that large scaled convection cells appeared both above and below the gradient zone. The exchange of water between the boundary layer and the core was also shown in these experiments. A video based PIV-technique was developed where a complete charging experiment could be recorded on a video tape. The pictures were analysed in an image processing program which made it possible to evaluate the whole velocity field. On basis of simulations for a case study representing the district heating system in Piteå it was found that heat quality degradation is not essential for the optimization of the storage volume. The different phenomena that influence the quality degradation are important however for optimizing the shape of a storage of a given size. The results from the measurements in the model heat storage's are useful mainly for validation of computer models for numerical prediction of velocity and temperature fields and as a basis for planning of experiments in larger storage's of commercial size. It was therefore decided to include in the study an evaluation of the importance of heat quality degradation for sizing of short term water heat storage's.

  • 5.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Brännström, Hugo
    Värmeåtervinning ur avloppsvatten vid Gällivare Reningsverk1983Rapport (Övrigt vetenskapligt)
  • 6.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Feasibility study of a heat storage in a district heating system in northern Sweden1994Ingår i: Thermal energy storage: better economy, environment, technology ; proceedings ; August 22 - 25, 1994, Espoo, Finland / CALORSTOCK '94, 6th International Conference on Thermal Energy Storage / [ed] M.T. Kangas, Helsinki: Helsinki University of Technology , 1994, s. 403-410Konferensbidrag (Refereegranskat)
  • 7.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Korttidslagring av hetvatten: förstudie1985Rapport (Övrigt vetenskapligt)
  • 8.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Korttidslagring av värme: mätning och utvärdering av ett el-baserat ackumulatorsystem1988Rapport (Övrigt vetenskapligt)
  • 9.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Phenomena that effect the thermal stratification in water heat storage's1991Ingår i: IEA-Workshop on Thermal Energy Storage and Low Energy Buildings: Tutzing, Germany 18 - 19 June 1991, München: Universität München , 1991Konferensbidrag (Refereegranskat)
  • 10.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Temperatures and velocities in a thermally stratified water heat storage1988Ingår i: Proceedings, 4th International Conference on Energy Storage for Building Heating and Cooling: JIGASTOCK 88 / [ed] J. Despois, French Agency for Energy Control, AFME , 1988, Vol. 1, s. 161-166Konferensbidrag (Refereegranskat)
  • 11.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    The establishing of a gradient zone and its effect on the velocity field in a water heat storage1989Ingår i: Proceedings / North Sun '88 - Solar Energy at High Latitudes / [ed] Lars Broman; Mats Rönnelid, Stockholm: Statens råd för byggnadsforskning , 1989Konferensbidrag (Refereegranskat)
  • 12.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Värmeleveranserna till Piteås fjärrvärmenät: resultat av mätningar som genomförts vid Backens hetvattencentral och Assi Kraftliner under 19901992Rapport (Övrigt vetenskapligt)
  • 13.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Gren, Per
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Benckert, Lars
    Temperatures and velocities near the gradient zone in a short term water heat storage1991Ingår i: Proceedings: Thermastock '91, International Conference on Thermal Energy Storage, Scheveningen, 13 - 16 May 1991, Utrecht: Novem , 1991Konferensbidrag (Refereegranskat)
  • 14.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Tiberg, Sven-Erik
    Veber, Pascal
    Luleå tekniska universitet.
    Use of video-based Particle Image Velocimetry technique for studies of velocity fields in a water heat storage vessel1995Ingår i: Experiments in Fluids, ISSN 0723-4864, E-ISSN 1432-1114, Vol. 18, nr 5, s. 383-388Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A video-based Particle Image Velocimetry technique has been developed. The technique is particularly suitable for measurement of small velocities, below 3 cm/s. It has proved to be useful for the documentation of non-stationary velocity fields in a scaled-down model of a water heat storage vessel. An ordinary video camera is used to record the in-plane movements of particles in a light sheet in seeded water. The hardware used, the experimental method and the accuracy of the method are discussed. The use of two commercially available software packages (NIH-Image and IGOR) for the analyses is described. Examples of velocity fields are presented, showing that the measuring technique can be used for studies of mixing near the inlet of the storage vessel and exchange of water between the boundary layer and the core.

  • 15.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Veber, Pascal
    Luleå tekniska universitet.
    Studies of velocity fields in a water heat storage with a video based particle image velocimetry technique1995Ingår i: Energy technologies for a sustainable future: : proceedings of the 30th Intersociety Energy Conversion Engineering Conference, IECEC, July 30 - August 4, 1995, Orlando, Florida / [ed] D. Yogi Goswami, New York: American Society of Mechanical Engineers , 1995Konferensbidrag (Refereegranskat)
  • 16.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Westerlund, Lars
    Egenskaper hos gaser, vätskor och fasta ämnen2001Ingår i: VVS 2000 Tabeller och diagram, Stockholm: Förlags AB VVS , 2001Kapitel i bok, del av antologi (Övrig (populärvetenskap, debatt, mm))
  • 17.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Westerlund, Lars
    Abel, Enno
    Värmeströmning2008Ingår i: VVS 2000 Tabeller och diagram, Stockholm: Förlags AB VVS , 2008Kapitel i bok, del av antologi (Övrig (populärvetenskap, debatt, mm))
  • 18.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Karlsson, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik.
    A new form of education: mechanics at the University of Lulea1978Ingår i: European Journal of Engineering Education, ISSN 0304-3797, E-ISSN 1469-5898, Vol. 3, nr 3/4, s. 277-283Artikel i tidskrift (Refereegranskat)
  • 19.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Keikkala, Gudrun
    Kask, Andrey
    Malyshev, Vladimir
    Murmansk State University.
    Minimizing greenhouse gas emissions by integration of a mineral processing and a district heating system for an adjacent town in North East Russia2006Konferensbidrag (Övrigt vetenskapligt)
  • 20.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Larsson, Mikael
    Grip, Carl-Erik
    Process integration in the steel industry2004Ingår i: Proceedings: 2nd International Conference on New Developments in Metallurgical Process Technology, Milano: Associazione Italiana di Metallurgia , 2004Konferensbidrag (Refereegranskat)
  • 21.
    Dahl, Jan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Strid, Martin
    Mushi, Isaac
    Environmental education at Moshi national vocational training centre: feasibility and importance of fourteen schemes a preliminary study1992Rapport (Övrigt vetenskapligt)
  • 22. Dumortier, L.
    et al.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Benckert, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Strömningslära och experimentell mekanik.
    Kjellström, Björn
    Evaluation of particle tracking velocimetry for studies of the flow in a boiler furnace1999Ingår i: Applied Modelling and Simulation, International conference, 1999Konferensbidrag (Refereegranskat)
  • 23.
    Grip, Carl-Erik
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dahl, Jan
    Söderström, Mats
    Linköpings universitet.
    Exergy as a means for process integration in integrated steel plants and process industries2009Ingår i: Stahl und Eisen (1881), ISSN 0340-4803, Vol. 129, nr 9, s. 2-8Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Exergy analysis can be a useful tool for process comparison and improvement in industrial energy systems. Examples from three branches are given: pulp and paper, bio refineries (ethanol) and steel production. The application and development of exergy analysis in an integrated steel plant is shown together with description and explanations on destroyed and lost exergy. Implementation for energy conservation and use as a pedagogic tool is discussed.

  • 24. Grip, Carl-Erik
    et al.
    Larsson, Mikael
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Energy optimization by means of process integration in an integrated steel plant with surrounding community2001Ingår i: 84th Steelmaking Conference proceedings: Baltimore, Maryland, March 25 - 28, 2001 / [ed] David L. Kanagy, Warrendale, Pa, 2001Konferensbidrag (Refereegranskat)
  • 25. Hermansson, Roger
    et al.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Isacsson, P.
    Schroeder, K.
    Supply of steam or nitrogen to obtain an inert atmosphere at the top of a solar water heat storage tank1997Ingår i: Proceedings of the 7th International Conference on Thermal Energy Storage: Megastock 97 / [ed] Kiyoshi Ochifuji, Sapporo, 1997Konferensbidrag (Refereegranskat)
  • 26.
    Ji, Xiaoyan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Lundgren, Joakim
    Wang, Chuan
    Center for Process Integration in Steelmaking, Swerea MEFOS, Luleå.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Grip, Carl-Erik
    Process simulation and energy optimization for the pulp and paper mill2010Ingår i: PRES 2010: 13th Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction, 28 August - 1 September 2010, Prague, Czech Republic / [ed] J.J. Klemeš; H.L. Lam; P.S. Varbanov, 2010, s. 283-288Konferensbidrag (Refereegranskat)
  • 27.
    Ji, Xiaoyan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Lundgren, Joakim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wang, Chuan
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Grip, Carl-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Simulation and energy optimization in a pulp and paper mill: Evaporation plant and digester2011Ingår i: Third International Conference on Applied Energy: 16-18 May 2011 - Perugia, Italy, 2011, s. 109-122Konferensbidrag (Refereegranskat)
    Abstract [en]

    A mathematical process integration model of a pulp and paper mill in the Northern Sweden has been developed. The main modelling focus has been put on the two main steam consumers (the evaporation plant and the digester), for which detailed material and energy balances have been established. Operational data have been used to validate the simulation results. By implementing these submodels into the complete plant model, the influence of different operation parameters on the overall plant performance has been investigated. Furthermore, introductory studies with the main objective to minimize the plant energy cost have been carried out. The correlation and differences between economic and energy have been discussed

  • 28.
    Ji, Xiaoyan
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Lundgren, Joakim
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wang, Chuan
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Grip, Carl-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Simulation and energy optimization of a pulp and paper mill: evaporation plant and digester2012Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 97, nr Spec. Issue, s. 30-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A detailed mathematical process integration model of a pulp and paper mill in the Northern Sweden has been developed. The main objective of this work has been set to describe the practical development of the model with particular emphasis on the development of the digester and evaporation plant sub-models. Actual plant measurements have been used to validate the model. By implementing the sub-models into the complete plant model, the influence of different operation parameters on the overall plant performance has been investigated. Furthermore, introductory studies with the main objective to minimize the plant energy cost have been carried out.

  • 29.
    Johansson, Tim
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Vesterlund, Mattias
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Olofsson, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Byggkonstruktion och -produktion.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Energy performance certificates and 3-dimensional city models as a means to reach national targets: A case study of the city of Kiruna2016Ingår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 116, s. 42-57Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Enhanced dissemination of information regarding energy saving and climate change targeted toward property owners is considered to be an important strategy in order to reach the Swedish national target of energy efficiency in the building sector by 2050. Here the municipality energy advisors and the national register for energy performance certificates can facilitate the mitigation of energy use in the building stock. So far few studies have focused on the practical road map to the national target of energy use on the city/district level and to the communication aspects with stakeholders in the creation of energy city models.In this paper a city energy model is developed based on the requests and need for visualization from a group of energy advisors. Six different scenarios are studied in order to analyze the possibility of reaching the energy targets specified by the government in the town of Kiruna. The results show that: (1) it is possible to automatically create city energy models using extract, transform and load tools based on spatial and non-spatial data from national registers and databases; (2) city energy models improve the understanding of energy use in buildings and can therefore be a valuable tool for energy advisors, real estate companies and urban planners. The case study of Kiruna showed that the proposed energy saving measures in the energy performance certificates need to be implemented and new buildings in the urban transformation must be of high energy standard in order to reach the national target in Kiruna.

  • 30. Keikkala, Gudrun
    et al.
    Kask, Andrey
    Murmansk State Technical University.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Malyshev, Vladimir
    Murmansk State University.
    Kotomkin, Viktor
    Kola Energy Efficiency Centre.
    Estimation of the potential for reduced greenhouse gas emission in north-east Russia: a comparison of energy use in mining, mineral processing and residential heating in Kiruna and Kirovsk-Apatity2007Ingår i: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 35, nr 3, s. 1452-1463Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The energy demand at Murmansk Oblast in North-East Russia is covered at 60% by fossil fuels and at 40% by electricity. This study estimates the potential for reduction of fossil fuel consumption and CO2-emissions at Murmansk Oblast. The study focus on the municipalities of Apatity and Kirovsk and the apatite ore mining company Apatit JSC . The potential for energy efficiency, reduced fossil fuel consumption and greenhouse gas emissions is estimated by comparison with the of city Kiruna in Northern Sweden, with a climate similar to that of North-East Russia, and with the iron ore mining company LKAB. This study shows that the potential for reduced CO2-emissions is about 630,700 tons CO2 annually in the municipalities of Apatity and Kirovsk or 6.3 tons of CO2 per capita, Apatit JSC not included. These results applied on Murmansk Oblast gives a potential for reduced CO2-emissions of about 6 Mtons annually in the municipalities together. The specific energy consumption at Apatit JSC is 6-7 times per ton product compared to LKAB. The mining has 4 times higher specific energy consumption per ton raw ore compared to LKAB.

  • 31. Larsson, Mikael
    et al.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Processintegration i ett handelsstålverk: inledande studie2000Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This prestudy is the first project of two where the overal aim is to develop techniques for process integration in the steel industry. This industry consumes a lot of energy and a tool for integration is of great importance for process optimazion and energy conservation in steel plants. This projekt involvs first an investigation of what kind of tool the Swedish steel industry needs for process integration (energy conservation, enviromental aspects). The second part contains data recording of relevant process parameters connected to the blast furnace at SSAB Luleå. The third part is a theoretical study of transient process parameters and how they affects the plant and surounding industries such as power plant Lulekraft.

  • 32. Larsson, Mikael
    et al.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Reduction of the specific energy use in an integrated steel plant: the effect of an optimisation model2003Ingår i: ISIJ International, ISSN 0915-1559, E-ISSN 1347-5460, Vol. 43, nr 10, s. 1664-1673Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Analysing the potential for improving the specific energy use in a steel mill can be difficult due to the interactions between the different subsystems. Changes in one unit can lead to several changes throughout the system. A process integration model taking into account the different interactions within the system is presented. The model is based on an optimising routine, making it a total analysis method for the steel plant system including the surroundings. The model is used to analyse the different possibilities for energy savings and practice changes within the system. The effect of optimising the total system versus separate optimisation of the different sub-processes is illustrated. The method development can serve as a benchmark for different steelmaking operations and constitute a basis for the continuous work involved in energy, material or economic analyses for the steel production system.

  • 33. Larsson, Mikael
    et al.
    Sandberg, Peter
    Division of Energy Systems, Department of Mechanical Engineering, Linköping Institute of Technology.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Söderström, Mats
    Division of Energy Systems, Department of Mechanical Engineering, Linköping Institute of Technology.
    Vuorinen, Henrik
    SSAB Tunnplåt AB.
    System gains from widening the system boundaries: analysis of the material and energy balance during renovation of a coke oven battery2004Ingår i: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 28, nr 10, s. 1051-1064Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The coke oven plant has a central role in the iron and steel making process in an integrated steel plant. The subject of this research is to study how the production and energy system at the steel industry, with a connected combined heat and power plant, is affected by renovation of the coke oven. The aim is to investigate the interaction between the different processes and how the choice of system boundary affects the operation practice for the steel plant. MILP-based optimization models have been developed and used for the evaluation. The analysis shows that it is very important to take the interactions between the different production units in the system into consideration when making the analysis. A system optimization with a boundary including the whole system has a greater potential for minimizing the total system cost than one that only includes the processes where the actual changes are made. Conclusions are also drawn regarding the production practice for the specific system

  • 34. Larsson, Mikael
    et al.
    Wang, C.
    Dahl, Jan
    Wedholm, Anita
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Magnusson, M.
    Lampinen, H-O
    Su, F.
    Grip, Carl-Erik
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Improved energy and material efficiency using new tools for global optimisation of residue material flows2004Ingår i: SCANMET II: 2nd International Conference on Process Development in Iron and Steelmaking, Luleå: MEFOS , 2004Konferensbidrag (Refereegranskat)
  • 35. Larsson, Mikael
    et al.
    Wang, Chuan
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Development of a method for analysing energy, environmental and economic efficiency for an integrated steel plant2006Ingår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 26, nr 13, s. 1353-1361Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The steel industry has faced several challenges during the years. There has always been an aspiration towards higher economic profitability for the system. During the mid 1970s and 1980s the energy crises caused a dramatic rise in energy costs, which led to an increased awareness in energy conservation. In recent years, climate change issues have become more important for the industry. The operating practises for an industrial system are often affected by external restrictions concerning the economical, energy and environmental efficiency of the system. There are a large number of ways to increase the system efficiency, e.g. installation of new process equipment, and practice changes. However, industrial systems such as an integrated steel plant consist of a system of several processes connected together with product and by-product interactions, where changes in one unit may result in changes throughout the total system. A process integration method focusing on the total integrated steel plant system by a simultaneous approach is adopted. An optimisation model is developed and used to study the effect of changes in the existing material and energy system. Applications of the model on the energy and material system have been made. The model can be used to analyse energy, environmental and economic aspects making it a powerful complement as a decision making tool. Conclusions about energy, environmental and economic effects are presented.

  • 36. Larsson, Mikael
    et al.
    Wang, Chuan
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Development of an integrated method for analysing energy, environmental and economic efficiency for an integrated steel plant2004Ingår i: CHISA 2004: 16th International Congress of Chemical and Process Engineering, 22 - 26 August 2004, Prague, Czech Republic, Prague, 2004Konferensbidrag (Refereegranskat)
  • 37. Larsson, Mikael
    et al.
    Wang, Chuan
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wedholm, Anita
    Samuelsson, Caisa
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Magnusson, Marcel
    Luleå tekniska universitet.
    Lampinen, Hans Olov
    SSAB Tunnplåt AB.
    Su, Fenwei
    SSAB Tunnplåt AB.
    Grip, Carl-Erik
    Improved energy and material efficiency using new tools for global optimisation of residue material flows2006Ingår i: International Journal of Green Energy, ISSN 1543-5075, E-ISSN 1543-5083, Vol. 3, nr 2, s. 127-137Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Residue materials generated in the metallurgical industry have gained an increasing importance, both from the points of view of energy and material supply. A joint process integration model for the integrated steel plant system is developed and used in this paper. It takes into account both residue materials and energy recirculation for the system. The potential for increased recirculation and the effect on the system from an environmental point of view is presented, and implementations and practical experiences are discussed. The model developed can serve as a benchmark for different steelmaking operations and constitute a basis for the continuous work involved in material, energy, environment or economic analyses for the steel production system.

  • 38.
    Lingebrant, Philip
    et al.
    Höganäs AB.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Larsson, Mikael
    Sandberg, Erik
    Center for Process Integration in Steelmaking, Swerea MEFOS, Luleå.
    System optimization of an electric steel making plant with sequenced production and dynamic stock level2012Ingår i: PRES 2012, 15th Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction, AIDIC Servizi S.r.l. , 2012, s. 523-528Konferensbidrag (Refereegranskat)
    Abstract [en]

    One third of the total steel production in the world today is produced by electrical steel making and is supposed to increase. It is a very energy intense process but for the production costs the scrap mix is nowadays clearly the most dominating cost factor. Because the ingoing raw material mix affects the energy consumption and the chemistry of the final product it is an important factor to control. A system optimization model for a generalized electric steelmaking plant has been developed. The vision has been to include a planned production sequence and a dynamic scrap stock level along with a full material- and energy balance connected to the processes. This gives the opportunity to run optimizations with restrictions similar to real production conditions. The generalized steelmaking plant produces hot rolled coils and five main processes are included in the model; a material pre-treatment process, an electric arc furnace, a ladle furnace, a continuous casting process and a hot rolling mill process. To estimate the chemical composition of the ingoing scrap grades, a regression model has been made based on process data from a Höganäs Sweden AB plant. Mixed Integer Linear Programming (MILP) has been used as the method for modeling the production system. Simulations and optimizations have been focused on changes in the chemical composition of certain scrap grades, restrictions of the availability of scrap grades and restrictions regarding the forecasted production sequence. The objectives used for the optimizations are production costs and total energy consumption. The model deliveries results in form of optimal raw-material mixes for the different steel grades defined in the model, optimal energy mix and optimal target temperatures for the sub-processes. Further it shows the effect on process parameters such as energy consumption, slag amount, off gas generation, injected carbon and oxygen etc. The model makes it possible to simulate scenarios that are expected for the future regarding new steel grades, availability of raw-materials and changed amount of tramp elements in the raw material used today. It is a good tool to find an optimal solution not only for a single heat but for a sequence of heats with varying chemical specifications

  • 39. Lundgren, Joakim
    et al.
    Hermansson, Roger
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    A new biomass based boiler concept for small district heating networks2001Ingår i: Proceedings of the 2001 Joint international combustion symposium: Toward efficient zero emission combustion - advances in air-fuel and oxy-fuel technlogies, Houston, Tex: International Energy Agency (IEA), 2001Konferensbidrag (Refereegranskat)
  • 40. Lundgren, Joakim
    et al.
    Hermansson, Roger
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Experimental studies during heat load fluctuations in a 500 kW wood-chips fired boiler2004Ingår i: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 26, nr 3, s. 255-267Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Several long-term experiments with fluctuating thermal outputs have been carried out in a newly developed biomass fuelled boiler suitable for small district heating networks. The experiments have been performed by either using the furnace only or the furnace together with a water heat store. Comparisons between these two operation strategies have been made concerning emissions and overall performance. Furthermore, the plant has been run to match a simulated heat demand during different seasons, in order to study the performance of the system during more realistic operation conditions. The results are very satisfactory concerning both performance and emissions, using any of the control strategies. Typical emissions of CO and NOx during the experiments are in the range of 10–50 mgNm−3 (5–25 mgMJ−1) and 130–175 mgNm−3 (60–90 mgMJ−1), respectively. However, during summer when the heat demand is low or zero, operational problems will occur if the heat store is excluded. Therefore, the main conclusion is that the most appropriate solution for a small district-heating system is to use a water heat store to match the heat load variations, while the furnace operates at as constant thermal output as possible.

  • 41.
    Lundgren, Joakim
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hermansson, Roger
    Dahl, Jan
    Experimental studies of a biomass boiler suitable for small district heating systems2004Ingår i: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 26, nr 5, s. 443-453Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Extensive experiments have been carried out in a newly developed furnace suitable for small district heating networks. The fuel is wood-chips with moisture content in the range of 30-58%. One of the unique features of this new furnace is the broad thermal output span, which makes it possible to run the boiler down to 10% of maximum heat load, with maintained low emissions of CO and total hydrocarbons (THC). The aim of this study has been to evaluate the performance of the combustion chamber during steady-state operation in the complete thermal output range. The experiments show very good results over the entire thermal output range. In the range 60 kW up to 500 kW, the average CO content in the stack gases is typically below 25 mg Nm-3(20 ppm) and the NOx concentration below 195 mg Nm-3(95 ppm) during steady state conditions. At lower thermal outputs, the average CO content is below 105 mg Nm-3(84 ppm). (All values standardised to 10 vol% O 2.)

  • 42. Lundgren, Joakim
    et al.
    Hermansson, Roger
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    New furnace designed for small-scale combustion of wet and inhomogeneous biomass fuels2005Ingår i: Biomass for energy, industry and climate protection: 14th European Biomass Conference & Exhibition ; proceedings of the international conference held in Paris, France, 17 - 21 October 2005 / [ed] L. Sjunnesson, Florence: ETA - Renewable Energies , 2005Konferensbidrag (Refereegranskat)
  • 43.
    Mattsson, Jonathan
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten. S-Group Solutions, Malmö.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Westerlund, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Ashley, Richard
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Viklander, Maria
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Impacts on rural wastewater systems in subarctic regions due to changes in inputs from households2018Ingår i: Journal of cold regions engineering, ISSN 0887-381X, E-ISSN 1943-5495, Vol. 32, nr 1, artikel-id 04017019Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The use of water-saving appliances and heat exchangers is becoming increasingly popular to decrease water consumption and recover energy from preheated water. However, such in-household changes can bring particular implications for subarctic rural areas, in terms of solids deposition in sewers and drops in performance of wastewater treatment plants (WWTPs), because these are already experiencing diminishing wastewater flows due to depopulation and seasonal dips in wastewater temperature resulting from infiltration into sewers. Hence, this study has considered two communities in Sweden, postulating three different cases with various scales of retrofitting and usage. The results indicate that the decrease in in-pipe velocities when all households are retrofitted with water-saving appliances could be counteracted by sewer relining, but not by the inclusion of a conventional estimate of infiltration. However, for the case in which retrofitting was combined with decreased usage of the appliances, the decrease in self-cleansing capacity could not be counteracted. The retrofitting of heat exchangers under shower trays in all households did not have a significant effect on treatment processes at the WWTP.

  • 44. Nordgren, Samuel
    et al.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Larsson, Mikael
    Lindblom, Bo
    LKAB.
    Savonen, Stefan
    LKAB.
    Tano, Kent
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser.
    Development of a process integration tool for an iron ore upgrading process system2007Ingår i: Mine planning and equipment selection and environmental issues and waste management in energy and mineral production: proceedings of the Sixteenth International Symposium on Mine Planning and Equipment Selection (MPES 2007) and the Tenth International Symposium on Environmental Issues and Waste Management in Energy and Mineral Production (SWEMP 2007) ; MPES 2007 and SWEMP 2007 ; held jointly in Bangkok, Thailand, December 11 - 13, 2007 / [ed] Rai K. Rai K., Irvine, Calif.: The Reading Matrix Inc. , 2007Konferensbidrag (Refereegranskat)
    Abstract [sv]

    Ett industriellt energisystem är föremål för en rad olika regleringar och restriktioner. God integration mellen olika enheter i produktionssystemet samt integration med samhället kan leda till förbättringar sett till både miljöpåverkan och energianvändning. Processintegration är en systemorienterad metodik för att analysera hela produktionssystem för att finna optimala systemlösningar. En matematisk programmeringsteknik är under utveckling för användning inom det svenska järnmalmsbolaget LKAB i Malmberget. Den matematiska modellen kommer baseras på en mass- och energibalans för de specifika enheterna inom den aktuella anläggningen. Utvecklingen av en bra matematisk modell kräver en systematisk kartläggning av de olika mass- och energiflödena som finns inom den aktuella anläggningen. I denna artikel ges en inledande beskrivning av den processintegrationsmodell som är under uppbyggnad.

  • 45.
    Nordgren, Samuel
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Wang, Chuan
    Lindblom, Bo
    LKAB.
    Process integration in an iron ore upgrading process system: analysis of mass and energy flows within a straight grate induration furnace2008Ingår i: 18th International Congress of Chemical and Process Engineering: 24th - 28th August - Prague - Czech Republic, ČSCHI - Czech Society of Chemical Engineering , 2008Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper is a part of a project which aim is to develop a process integration model for the Swedish iron ore company LKAB's production system in Malmberget. Within the facility, there are two pelletising plants which were started up 1973 and 2006, respectively. Both pelletising plants are using the straight grate induration furnace, and they are the most energy intense process units within the facility. Basically a straight grate induration furnace consists of three different zones, i.e. a drying zone, a firing zone and a cooling zone, and their purpose is to upgrade crude iron ore to the final product of iron ore pellet. As an initial step of the project, the mass and energy flows within a straight grate induration furnace have been analysed. The outcome of the analysis will in the future constitute as a basis towards a total mass and energy balance for the whole production chain within the facility in Malmberget. Later on the model will be used to optimize, primarily, energy consumption and environmental impact.

  • 46.
    Nordgren, Samuel
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Lindblom, Bo
    LKAB, Technology and Business Development.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Sandberg, Johan
    LKAB, Technology and Business Development.
    Effective Use of Available Heat for Maintaining a High Green Pellet Temperature2013Ingår i: ISIJ International, ISSN 0915-1559, E-ISSN 1347-5460, Vol. 53, nr 12, s. 2072-2079Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In iron ore pellet production, an increased green pellet temperature has a positive influence on the straight grate induration furnace. Previous studies show that this can lead to both higher production capacity of the induration furnace and also reduced specific oil consumption. The aim of this study is to apply the process integration concept to analyze how to maintain a high green pellet temperature by using the available heat more effectively. The heat is today used for the indoor climate and is delivered by electricity boilers and a waste heat recovery boiler that is installed next to the induration furnace, using hot gases from the furnace to heat water. This work will however assume that one can use the heat from the waste heat recovery boiler to preheat the material stream. By optimizing the cold section of the pelletizing plant, using process integration and the mathematical modeling approach in combination with the newly developed Optimal Solution Space Method, the results show that it is possible to increase the green pellet temperature and also reduce the energy cost by using the available energy in a more efficient way. It is also showing that by retrofitting the system so that the waste heat from the waste heat recovery boiler is used to preheat the material stream, this also leads to reduced energy cost and also increased production of iron ore pellet since the temperature of green pellet will be higher.

  • 47.
    Pericault, Youen
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Vesterlund, Mattias
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Olsson, Göran
    Elgocell AB.
    District heat tracing of water and sewer lines in Kiruna, Sweden2016Konferensbidrag (Övrigt vetenskapligt)
  • 48.
    Risberg, Daniel
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Vesterlund, Mattias
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Risberg, Mikael
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hedström, Annelie
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Arkitektur och vatten.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Westerlund, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Hållbara, integrerade energi- och VA-system2014Rapport (Övrigt vetenskapligt)
  • 49.
    Risberg, Daniel
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Vesterlund, Mattias
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Westerlund, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    CFD simulation and evaluation of different heating systems installed in low energy building located in sub-arctic climate2015Ingår i: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 89, s. 160-169Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Computational Fluid Dynamics (CFD) simulations were used to study the indoor climate in a low energy building in northern Sweden. The building’s low heat requirement raise the prospect of using a relatively simple and inexpensive heating system to maintain an acceptable indoor environment, even in the face of extremely low outdoor temperature. To explore the viability of this approach, the indoor climate in the building was studied considering three different heating systems: a floor heating system, air heating through the ventilation system and an air heat pump installation with one fan coil unit. The floor heating system provided the most uniform operative temperature distribution and was the only heating system that fully satisfied the recommendations to achieve tolerable indoor climate set by the Swedish authorities. On the contrary, air heating and the air heat pump created a relatively uneven distribution of air velocities and temperatures, and none of them fulfills the specified recommendations. From the economic point of view, the air heat pump system was cheaper to be installed but produced a less pleasant indoor environment than the other investigated heating systems.

  • 50.
    Risberg, Daniel
    et al.
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Vesterlund, Mattias
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Westerlund, Lars
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    Dahl, Jan
    Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, Energivetenskap.
    CFD simulations of the indoor climate of a low energy building in a sub-Arctic climate: an evaluation of different heating systems2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    Computational Fluid Dynamics (CFD) simulations were used to study the indoor climate in a low energy building in northern Sweden. The building’s low heat requirements raise the prospect of using relatively simple and inexpensive heating systems to maintain an acceptable indoor environment, even in the face of extremely low outdoor temperatures. To explore the viability of this approach, the indoor temperature and air velocity distribution inside the building were studied assuming that it was fitted with one of four different heating systems: radiators, an underfloor heating system, a pellet stove, and an air/air heat pump. The radiators produced a relatively uniform horizontal temperature distribution throughout the house. The underfloor system provided an even more uniform temperature distribution. In contrast, the heat pump created a relatively uneven internal temperature distribution. Several locations for the pump were considered, all of which had significant drawbacks. The pellet stove produced a more even temperature distribution than the pump but not to the same extent as the underfloor system or the radiators. Overall, point source heating systems cost less to fit and operate over a given period of time but produce a less clement indoor environment than distributed heating systems.

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