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  • 101.
    Natarajan, Karthikeyan
    et al.
    University of Eastern Finland.
    Leduc, Sylvain
    International Institute for Applied System Analysis (IIASA), Laxenburg.
    Pelkonen, Paavo
    Tomppo, Erkki
    Finnish Forest Research Institute (METLA), Vantaa.
    Dotzauer, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Optimal Locations for Methanol and CHP Production in Eastern Finland2012Ingår i: Bioenergy Research, ISSN 1939-1234, Vol. 5, nr 2, s. 412-423Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Finland considers energy production from woody biomass as an efficient energy planning strategy to increase the domestic renewable energy production in order to substitute fossil fuel consumption and reduce greenhouse gas emissions. Consequently, a number of developmental activities are implemented in the country, and one of them is the installation of second generation liquid biofuel demonstration plants. In this study, two gasification-based biomass conversion technologies, methanol and combined heat and power (CHP) production, are assessed for commercialization. Spatial information on forest resources, sawmill residues, existing biomass-based industries, energy demand regions, possible plant locations, and a transport network of Eastern Finland is fed into a geographically explicit Mixed Integer Programming model to minimize the costs of the entire supply chain which includes the biomass supply, biomass and biofuel transportation, biomass conversion, energy distribution, and emissions. The model generates a solution by determining the optimal number, locations, and technology mix of bioenergy production plants. Scenarios were created with a focus on biomass and energy demand, plant characteristics, and cost variations. The model results state that the biomass supply and high energy demand are found to have a profound influence on the potential bioenergy production plant locations. The results show that methanol can be produced in Eastern Finland under current market conditions at an average cost of 0.22 €/l with heat sales (0.34 €/l without heat sales). The introduction of energy policy tools, like cost for carbon, showed a significant influence on the choice of technology and CO 2 emission reductions. The results revealed that the methanol technology was preferred over the CHP technology at higher carbon dioxide cost (>145 €/t CO2). The results indicate that two methanol plants (360 MW biomass) are needed to be built to meet the transport fuel demand of Eastern Finland

  • 102.
    Nordlander, Eva
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Yan, Jinyue
    KTH.
    Modeling of a full-scale biogas plant using a dynamic neural network2013Konferensbidrag (Refereegranskat)
  • 103.
    Nordlander, Eva
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Olsson, Jesper
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Simulation of energy balance and carbon dioxide emission for microalgae introduction in wastewater treatment plants2017Ingår i: Algal Research, ISSN 2211-9264, Vol. 24, nr part A, s. 251-260Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A case study is described in which the activated sludge process is replaced with a microalgae-activated sludge process. The effects on the heat and electricity consumption and carbon dioxide emissions were evaluated in a system model, based on mass and energy balances of biological treatment and sludge handling process steps. Data for use in the model was gathered from three wastewater treatment plants in Sweden. The evaluation showed that the introduction of microalgae could reduce electricity and heat consumption as well as CO2 emissions but would require large land areas. The study concludes that a 12-fold increase in the basin surface area would result in reductions of 26–35% in electricity consumption, 7–32% in heat consumption and 22–54% in carbon dioxide emissions. This process may be suitable for wastewater treatment plants in Nordic countries, where there is a higher organic load in summer than at other times of the year. During the summer period (May to August) electricity consumption was reduced by 50–68%, heat consumption was reduced by 13–63% and carbon dioxide emissions were reduced by 43–103%.

  • 104.
    Nylund, Simon
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Wenstedt, Niklas
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    WELL-TO-WHEELS ANALYSIS OF HEAVY-DUTY TRUCK FUELS: A comparison between LNG, LBG and Diese2019Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    Heavy-duty trucks accounts for 25% CO2 emissions in Sweden and there is approximately 12.6 million heavy-duty vehicles in the EU with different types of fuel and utilization areas. EU is implementing increased legislations to reduce emissions and increase the use of biofuel and members of the EU is starting to ban the use of diesel trucks in local areas, which drives the need to find other suitable fuel. Therefore, to study and compare the emissions and energy demand in the heavy-duty truck industry a case study is created. Which focuses on production and processing, transportation, distribution and fuel consumption. Cultivation of maize and anaerobic digestion of maize, waste and manure is included as well. Data gathered from the collaboration between the European Commission’s Joint Research Centre, eucar and Concawe (JEC) is used to create scenarios and these are validated with previous studies. The case study includes seven LNG cases, three LBG cases and two diesel cases together with several other cases collected for verification. Furthermore, potential boil-off and leakage during maintenance is included to further estimate the possible emissions correlated with LNG and LBG vehicles. The Well-to-Wheels analysis resulted in most LNG and LBG cases having higher energy input compared to diesel. LBG has the lowest emissions of greenhouse gases. The transportation method and distance are the most important aspects for the Well-to-Tank analysis. The fuel consumption is the main source of emissions and energy input in the Tankto-Wheels analysis. In conclusion, the transportation and fuel consumption are the greatest contributors of emissions and energy demand in the complete Well-to-Wheels analysis. 

  • 105.
    Olsson, A.
    et al.
    Royal Institute of Technology, Stockholm.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Lind, M.
    ZeroMission, Stockholm.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Potential for carbon sequestration and mitigation of climate change by irrigation of grasslands2014Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 136, s. 1145-1154Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The climate change mitigation potential of irrigation powered by a photovoltaic water pumping system (PVWPS) to restore degraded grasslands has been investigated using the Intergovernmental Panel on Climate Change (IPCC) 2006 Guidelines for National Greenhouse Gas Inventories for Agriculture, Forestry and Other Land Use. The purpose of this study is to develop a generic and simple method to estimate the climate change mitigation benefit of a PVWPS. The possibility to develop carbon credits for the carbon offset markets has also been studied comparing carbon sequestration in grasslands to other carbon sequestration projects. The soil carbon sequestration following irrigation of the grassland is calculated as an annual increase in the soil organic carbon pool.The PVWPS can also generate an excess of electricity when irrigation is not needed and the emissions reductions due to substitution of grid electricity give additional climate change mitigation potential.The results from this study show that the carbon sequestration and emissions reductions benefits per land area using a PVWPS for irrigating grasslands are comparable to other carbon sequestration options such as switching to no-till practice. Soil carbon in irrigated grasslands is increased with over 60% relative to severely degraded grasslands and if nitrogen fixing species are introduced the increase in soil organic carbon can be almost 80%. Renewable electricity generation by the PVWPS will further increase the mitigation benefit of the system with 70-90%. When applying the methodology developed in this paper to a case in Qinghai, China, we conclude that using a PVWPS to restore degraded grasslands for increased grass production and desertification control has a climate change mitigation benefit of 148Mg (1Mg=1metricton) CO2-equivalents (CO2-eq) per hectare in a cold temperate, dry climate during a 20year process of soil organic carbon sequestration and emissions reductions. Leakage due to an increase in N2O emissions from the additional biomass production and introduction of nitrogen fixing species is included in this result. The most important conclusion from our case is that if soil carbon sequestration is lower than 24Mg CO2-eq per hectare including leakage, then the climate change mitigation benefit is larger if PV is used to produce electricity for the grid.

  • 106.
    Patrizio, Piera
    et al.
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria..
    Leduc, Sylvain
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria..
    Kraxner, Florian
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria..
    Fuss, Sabine
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria.;Mercator Res Inst Global Commons & Climate Change, Working Grp Sustainable Resource Management & Glo, Torgauer Str 12-15, D-10829 Berlin, Germany..
    Kindermann, Georg
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria..
    Mesfun, Sennai
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria..
    Spokas, Kasparas
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria.;Princeton Univ, Dept Civil & Environm Engn, Princeton, NJ 08544 USA..
    Mendoza, Alma
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria..
    Mac Dowell, Niall
    Imperial Coll London, Ctr Environm Policy, London SW7 1NE, England.;Imperial Coll London, Ctr Proc Syst Engn, London SW7 1NA, England..
    Wetterlund, Elisabeth
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria.;Lulea Univ Technol, Div Energy Sci, Energy Engn, S-97187 Lulea, Sweden..
    Lundgren, Joakim
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria.;Lulea Univ Technol, Div Energy Sci, Energy Engn, S-97187 Lulea, Sweden..
    Dotzauer, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yowargana, Ping
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria..
    Obersteiner, Michael
    IIASA, Ecosyst Serv & Management Program ESM, Schlosspl 1, A-2361 Laxenburg, Austria..
    Reducing US Coal Emissions Can Boost Employment2018Ingår i: JOULE, ISSN 2542-4351, Vol. 2, nr 12, s. 2633-2648Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Concerns have been voiced that implementing climate change mitigation measures could come at the cost of employment, especially in the context of the US coal sector. However, repurposing US coal plants presents an opportunity to address emission mitigation and job creation, if the right technology change is adopted. In this study, the transformation of the US coal sector until 2050 is modeled to achieve ambitious climate targets. Results show that the costoptimal strategy for meeting 2050 emission reductions consistent with 2 degrees C stabilization pathways is through the early deployment of BECCS and by replacing 50% of aging coal plants with natural gas plants. This strategy addresses the concerns surrounding employment for coal workers by retaining 40,000 jobs, and creating 22,000 additional jobs by mid-century. Climate change mitigation does not have to come at the cost of employment, and policymakers could seek to take advantage of the social co-benefits of mitigation.

  • 107.
    Persson, Tomas
    et al.
    Högskolan i Dalarna.
    Riedel, Jochen
    Högskolan i Dalarna.
    Berghel, Jonas
    Karlstad University.
    Bexell, Ulf
    Högskolan i Dalarna.
    Win, Kaung Myat
    Högskolan i Dalarna.
    Emissions and deposit properties from combustion of wood pellet with magnesium additives2013Ingår i: Ranliao Huaxue Xuebao/Journal of Fuel Chemistry and Technology, ISSN 0253-2409, Vol. 41, nr 5, s. 530-539Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This work studies the amount of gaseous and particle emissions and deposits on heat exchanger surfaces in a boiler fired with commercially available pellets and with pellets primed with magnesium oxide and magnesium hydroxide. The combustion experiments were performed on a residential boiler of 20 kW. Substrates placed in the heat exchanger was analysed with SEM-EDX-mapping to evaluate the chemical composition of the deposits. The results show that particle emissions (PM 2.5) using the additives increased by about 50% and the mass of the deposits in the flue gas heat exchanger (excluding loose fly ash) increased by about 25% compared to the combustion of pellets without additives. The amount of additives was found to be eight times higher than the amount of the main alkali metals potassium (K) and sodium (Na) which leads to the assumption that the additives were overdosed and therefore caused the problems reported. The SEM analysis of the substrates placed in the flue gas heat exchanger indicate that the deposits of sodium (Na), potassium (K), chlorine (Cl) and sulphur (S) decrease using the additives. If this was due to the expected chemical reactions or due to the loose fly ash covering the substrates after the test, could not be determined in this study.

  • 108.
    Pettersson, Hanna
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Törnvall, Elin
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Efterbehandling av biogödsel: Ett försök med avskiljning och uppsamling av kväve och vatten genom ammoniakstripping i en efterhygieniseringsprocess2017Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    During this master thesis, the possibility of ammonia removal from digestate in combination with after hygienization has been investigated. The aim of the work was to see how much ammonia that could be removed but also the properties of other process parameters such as TS/VS content, pH and alkalinity of the digestate. It was also of interest to study the energy balances for a process that combines ammonia stripping with after hygienization. The purpose of hygienization in a biogas plant is to kill pathogens. To study ammonia stripping combined with after hygienization, a prototype of an ammonia stripper was built in a laboratory. The digestate was heated to the hygienization temperature of 70 °C and air was led through with the help of a peristaltic pump by the end of the system. Condensate was trapped in a bottle by cooling the tube and the gases were brought to another bottle containing 1 M sulfuric acid. Ammonia and sulfuric acid reacted and formed ammonium sulfate. The process was also tested with closed system using vacuum to decrease the boiling point and thereby create more condensate. The results from the experiments showed that with an air stripping process most of the ammonium was trapped in the sulfuric acid while with a vacuum process more ammonium was trapped in the condensate. The most important parameters to achieve a good ammonia removal were air flow and time. With the vacuum system, more condensate was removed. The removal of condensate could make it possible to recirculate process fluid from the stripping process and thereby save energy in the centrifugation part which is used to create a solid part of the bio digestate. It was concluded from the experiments that air stripping is more effective when it comes to ammonium recovery. The process could be improved by using higher air flow which could decrease the time to less than one hour, which is the desired hygienization time. However, it is desired to keep the pump flow as low as possible since it is energy consuming. A chemical increase of the pH would also be of interest to try since previous tests showed a strong correlation between high pH-value and good ammonia stripping. More tests overall are of interest to ensure a reliable result. Still, the combination of after-hygienization and ammonia stripping would contribute to a better environment and a sustainable agriculture with a natural and nutritious digestate.

  • 109.
    Pettersson, Martin
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Magicads potential för ventilationssystem: - en studie om beräkningsprogrammets tillförlitlighet angående tryckfall i ett ventilationssystem med ett tilluft -och frånluftssystem2018Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Detta examensarbete är en del av energiingenjörsutbildningen i värmeteknik på Mälardalens högskola i Västerås och är en fördjupning inom ventilationsteknik. Arbetet har utförts med hjälp av företaget VentPartner i Västerås som har tillgodosett med det aktuella studerande ventilationssystemet.

    Syftet med detta examensarbete var att undersöka om beräkningsprogrammet MagiCAD är tillförlitligt med avseende på tryckfall i ventilationssystem samt vilken potential och påverkan programmet eventuellt kan ha för ventilationsbranschen. Tre stycken olika beräkningsmetoder för tryckfall har utförts; MagiCAD simuleringar, handberäkningar med formler och diagram samt fysiska mätningar med mätinstrument. Syftet har gått ut på att göra en jämförelse mellan dessa tre beräkningsmetoder för att med hjälp och tillsammans med tidigare forskning fastställa MagiCADs trovärdighet samt undersöka eventuella brister hos beräkningsprogrammet.

    Det studerade ventilationssystemet för den aktuella studien var ett till- och frånluftssystem på VentPartners kontor i Västerås. Systemet hade ett tilluftsflöde på 250 l/s och ett frånluftsflöde på 260 l/s.

    I arbetets tidiga skeende utfördes först ett platsbesök i syfte att ta fram referensdata av det utvalda ventilationssystemet. Med hjälp av stege, tumstock och en utskriven skiss av systemet samlade man in längd och dimensioner på kanaler, kanalernas placering i höjdled, produktinformation på don, spjäll och ljuddämpare. Därefter utfördes själva designen och uppritningen av ventilationssystemet i MagiCAD med hjälp av referensdata. När det projekterade ventilationssystemet var färdigt i MagiCAD utfördes själva tryckfallssimuleringen i beräkningsprogrammet. De manuella handberäkningarna utfördes med hjälp av formler och diagram och genomfördes i programmet Excel. De fysiska mätningarna utfördes vid ett separat platsbesök på VentPartners kontor och utfördes med universalmätaren Swema 3000 som Ventpartner tillgodosatte.

    Resultatet av tryckfallen ifrån MagiCAD simuleringarna och handberäkningarna skiljde sig endast en aning, både för tillufts -och frånluftssystemet. Medans tryckfallen ifrån de fysiska mätningarna skiljde sig betydligt mer jämförelsevis mot de andra två beräkningsmetoderna. Detta berodde på att MagiCAD och handberäkningarna utgår ifrån ideala förhållanden, vilket verkligheten aldrig är.

    Slutsatsen blev att beräkningsprogrammet MagiCAD är ett väldigt komplett och behagligt projekterings -och simuleringsprogram som är tillförlitligt. Dock har programmet sina brister i en del anpassningsfunktioner till verkligheten, men potentialen för framtiden ser ljus ut.  

  • 110.
    Rahman, Moksadur
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zaccaria, Valentina
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Xin, Zhao
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Diagnostics-Oriented Modelling of Micro Gas Turbines for Fleet Monitoring and Maintenance Optimization2018Ingår i: Processes, ISSN 2227-9717, Vol. 6, nr 11Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The market for the small-scale micro gas turbine is expected to grow rapidly in the coming years. Especially, utilization of commercial off-the-shelf components is rapidly reducing the cost of ownership and maintenance, which is paving the way for vast adoption of such units. However, to meet the high-reliability requirements of power generators, there is an acute need of a real-time monitoring system that will be able to detect faults and performance degradation, and thus allow preventive maintenance of these units to decrease downtime. In this paper, a micro gas turbine based combined heat and power system is modelled and used for development of physics-based diagnostic approaches. Different diagnostic schemes for performance monitoring of micro gas turbines are investigated.

  • 111.
    Salman, Chaudhary Awais
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Integration of thermochemical processes with existing waste management industries to enhance biomethane production2018Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    I de flesta avfallshanteringsanläggningarna separeras avfallet i olika fraktioner och behandlas i lämpliga processer. Etablerade tekniker som förbränning av avfall för kombinerad el- och värmeproduktion och produktion av biometan genom rötning (AD) av biologiskt nedbrytbart avfall fungerar bra som fristående processer. Det finns dock några nackdelar med de etablerade processerna för omvandling av avfall till energi (WtE), t ex har traditionella kraftvärmeverk höga energiverkningsgrad, men lägre elverkningsgrad och värmproduktionen är beroende av lokal efterfrågan och säsongsvariationer. På liknande sätt innehåller biologiskt nedbrytbart avfall som används till rötning, lignocellulosa eller eller så kallat grönavfall. På grund av lägre biologisknedbrytningav avfall med lignocellulos används endast en del av detta för rötning medan resten förbränns, vilket ökar transportkostnaderna. Större fördelar med avseende på energi och ekonomi kan uppnås genom att integrera de nya WtE-processerna med befintlig teknik.

     

    Avhandlingen syftar till att utforma energieffektiva och kostnadseffektiva bioraffinaderier genom att integrera befintliga avfallshanteringsanläggningar med termokemisk behandling av avfall. En systemanalys av två processintegrationskoncept har studerats genom modellering och simulering. En är processintegrering av förgasning med befintliga kraftverk, och den andra är integrationen av pyrolys med befintliga rötningsanläggningar. För integration av kraftvärme och förgasning utvärderas rimliga gränser för sdriften av en anläggning genom att jämföra integreration av tre typer av förgasare och den tekniskt och ekonomiskt bästa integrerade processen identifieras. För integrering av pyrolys och rötning presenteras en ny processkonfiguration som kopplar rötning av biologiskt nedbrytbart avfall med pyrolys av avfall som innehåller lignocellulosl. Biokol från pyrolysen tillsätts rötkammaren som en adsorbent för att öka biometanhalten. Dessutom omvandlas de ångor som framställs genom pyrolysprocessen till biometan. Två olika omvandlingsprocesser för att konvertera pyrolysångor till bio-metan jämförs, dvs katalytisk metanisering och biometanisering.

     

    Resultaten visar att processintegration kan bidra till att minska produktionskostnaderna för biometan genom förgasning och pyrolys genom integration med kraftvärme (CHP) respektive rötning (AD). Processintegrationen kan också utnyttja infrastrukturen och produkterna från befintliga industrier och öka den totala processeffektiviteten. Av alla undersökta förgasare producerar indirekt förgasning mer biometan jämfört med cirkulerande bädd och flödesförgasare när den integreras med ett befintligt kraftvärmeverk, med upp till 85 % verkningsgrad. Integreringen av kraftvärme och förgasning kan producera mer biometan under säsonger med låg efterfrågan av värme, utan att störa kraftvärme-driften. När det gäller förgasningsstorleken kan förgasarens flexibla kapacitet integreras med kraftvärme för att producera biometan utan att ändra den årliga värmeproduktionen. Ur ett ekonomiskt perspektiv kräver indirekta förgasaren lägre kapitalinvesteringar och ger högre intäkter på grund av färre utrustningsdelar än cirkulerande fluidiserad förgasare och flödesförgare. Integreringen av pyrolys med rötnings-processen kan nästan dubbla bio-metanproduktionen och öka verkningsgraden till 67 %. Integrationen är attraktiv för investering när katalytisk metanisering används istället för biometanisering av syngas. Katalytisk metanisering ger en avkastning på 16 %, med sex års återbetlaningstid.

     

    Den viktigaste slutsatsen från denna avhandling är att produktionen av bio-metan kan förbättras genom processintegration av förgasning med kraftvärm och pyrolys med rötning. Ökningen av bio-metanproduktion ökar emellertid även efterfrågan på avfall till integrerade bioraffinaderier. Därför kommer storleken av förgasare och pyrolysprocessen att vara avgörande för att bestämma integrationsnivån av de studerade bioraffinaderierna.

  • 112.
    Salman, Chaudhary Awais
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Future directions for CHP plants using biomass and waste - Adding production of vehicle fuels2019Ingår i: E3S Web of Conferences, EDP Sciences , 2019, artikel-id 01006Konferensbidrag (Refereegranskat)
    Abstract [en]

    In Northern Europe, the production of many biobased CHP plants is getting affected due to the enormous expansion of wind and solar power. In addition, heat demand varies throughout the year, and existing CHP plants show less technical performance and suffer economically. By integrating the existing CHP plants with other processes for the production of chemicals, they can be operated more hours, provide operational and production flexibility and thus increase efficiency and profitability. In this paper, we look at a possible solution by converting an existing CHP plant into integrated biorefinery by retrofitting pyrolysis and gasification process. Pyrolysis is retrofitted in an existed CHP plant. Bio-oil obtained from pyrolysis is upgraded to vehicle grade biofuels. Gasification process located upfront of CHP plant provides the hydrogen required for upgradation of biofuel. The results show that a pyrolysis plant with 18 ton/h feed handling capacity (90 MWth), when integrated with gasification for hydrogen requirement and CHP plant for heat can produce 5.2 ton/h of gasoline/diesel grade biofuels. The system integration gives positive economic benefits too but the annual operating hours can impact economic performance. 

  • 113.
    Sannö, Anna
    et al.
    Mälardalens högskola, Akademin för innovation, design och teknik, Innovation och produktrealisering. School of Science and Technology, Örebro University, Örebro, Sweden.
    Johansson, M. T.
    Division of Energy Systems, Linköping University, Linköping, Sweden.
    Thollander, P.
    Division of Energy Systems, Linköping University, Linköping, Sweden.
    Wollin, J.
    Volvo Construction Equipment, Gothenburg, Sweden.
    Sjögren, B.
    IVL, Swedish Environmental Institute, Gothenburg, Sweden.
    Approaching sustainable energy management operations in a multinational industrial corporation2019Ingår i: Sustainability, ISSN 2071-1050, E-ISSN 2071-1050, Vol. 11, nr 3, artikel-id 754Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A large share of the energy efficiency improvement measures available for industrial companies remains unadopted due to the existence of various barriers to energy efficiency. One of the main means of overcoming barriers to energy efficiency is via energy management operations. The major parts of the published scientific papers have covered energy management on a company level or on a sector level. However, so far, the literature is scarce regarding empirical studies on energy management on a corporate level. With the aim of filling the research gap, the aim of this paper is to empirically assess the performance of an in-house energy management program adoption from the year of initiation and four years ahead in the multinational company Volvo CE. The paper was conducted as a case study including a participative approach, which has not previously been done in energy management research. This paper adds value, through complementing the existing literature on energy management on a factory or sector level, by highlighting the importance of leadership, speed of execution, and cultural transformation on a corporate level. 

  • 114.
    Schmidt, Johannes
    et al.
    Univ Nat Resources & Life Sci, Austria.
    Leduc, Sylvain
    Int Inst Appl Syst Anal, Austria.
    Dotzauer, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Schmid, Erwin
    Univ Nat Resources & Life Sci, Austria.
    Cost-effective policy instruments for greenhouse gas emission reduction and fossil fuel substitution through bioenergy production in Austria2011Ingår i: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 39, nr 6, s. 3261-3280Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Climate change mitigation and security of energy supply are important targets of Austrian energy policy. Bioenergy production based on resources from agriculture and forestry is an important option for attaining these targets. To increase the share of bioenergy in the energy supply, supporting policy instruments are necessary. The cost-effectiveness of these instruments in attaining policy targets depends on the availability of bioenergy technologies. Advanced technologies such as second-generation biofuels, biomass gasification for power production, and bioenergy with carbon capture and storage (BECCS) will likely change the performance of policy instruments. This article assesses the cost-effectiveness of energy policy instruments, considering new bioenergy technologies for the year 2030, with respect to greenhouse gas emission (GHG) reduction and fossil fuel substitution. Instruments that directly subsidize bioenergy are compared with instruments that aim at reducing GHG emissions. A spatially explicit modeling approach is used to account for biomass supply and energy distribution costs in Austria. Results indicate that a carbon tax performs cost-effectively with respect to both policy targets if BECCS is not available. However, the availability of BECCS creates a trade-off between GHG emission reduction and fossil fuel substitution. Biofuel blending obligations are costly in terms of attaining the policy targets

  • 115.
    Shen, B.
    et al.
    Environmental Energy Technologies Divisions, Lawrence Berkeley National Laboratory, United States .
    Ghatikar, G.
    Environmental Energy Technologies Divisions, Lawrence Berkeley National Laboratory, United States .
    Lei, Zeng
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. CLASP China, Beijing, China .
    Li, J.
    Environmental Energy Technologies Divisions, Lawrence Berkeley National Laboratory, United States .
    Wikler, G.
    EnerNOC, Inc., United States .
    Martin, P.
    EnerNOC, Inc., United States .
    The role of regulatory reforms, market changes, and technology development to make demand response a viable resource in meeting energy challenges2014Ingår i: Applied Energy, ISSN 0306-2619, Vol. 130, s. 814-823Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In recent years, demand response and load control automation has gained increased attention from regulators, system operators, utilities, market aggregators, and product vendors. It has become a cost-effective demand-side alternative to traditional supply-side generation technologies to balance the power grid, enable grid integration of renewable energy, and meet growing demands for electricity. There are several factors that have played a role in the development of demand response programs. Existing research are however limited on reviewing in a systematic approach how these factors work together to drive this development. This paper makes an attempt to fill this gap. It provides a comprehensive overview on how policy and regulations, electricity market reform, and technological advancement in the US and other countries have worked for demand response to become a viable demand-side resource to address the energy and environmental challenges. The paper also offers specific recommendations on actions needed to capture untapped demand response potentials in countries that have developed active demand response programs as well as countries that plan to pursue demand response.

  • 116.
    Skvaril, Jan
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Near-Infrared Spectroscopy and Extractive Probe Sampling for Biomass and Combustion Characterization2017Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Biomass is characterized by highly variable properties. It can be converted to more valuable energy forms and products through a variety of conversion processes. This thesis focuses on addressing several important issues related to combustion and pulping.

    Experimental investigations were carried out on a biomass-fired industrial fluidized-bed boiler. The observed combustion asymmetry was explained by an imbalance in the fuel feed. Increased levels of carbon monoxide were detected close to boiler walls which contribute significantly to the risk of wall corrosion.

    Moreover, extensive literature analysis showed that near-infrared spectroscopy (NIRS) has a great potential to provide property information for heterogeneous feedstocks or products, and to directly monitor processes producing/processing biofuels in real-time. The developed NIRS-based models were able to predict characteristics such as heating value, ash content and glass content. A study focusing on the influence of different spectra acquisition parameters on lignin quantification was carried out. Spectral data acquired on moving woodchips were found to increase the representativeness of the spectral measurements leading to improvements in model performance.

    The present thesis demonstrates the potential of developing NIRS-based soft-sensors for characterization of biomass properties. The on-line installation of such sensors in an industrial setting can enable feed-forward process control, diagnostics and optimization.

  • 117.
    Skvaril, Jan
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Application of Near Infrared Spectroscopy for Rapid Characterization of Feedstock Material in Pulp and Paper Industry2015Ingår i: Book of abstracts, 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Pulp digesters can be continuous or batch reactors with significant residence time which are fed with woodchips and cooking chemicals. They deliver the pulp-fibers that are used in the production of paper, as well as black liquor that is combusted in the chemical recovery boiler. The possibility to measure what is happening inside the digester is limited. The most important quality properties of the feedstock material is content of lignin, which is being dissolved during the process, and related material reactivity. Pulp quality after the process is measured by Kappa number which is a measure of residual lignin in the pulp. One of the biggest challenges in pulp production process is the great variability in feedstock material properties. If the process is not adjusted by well-timed and appropriate operational control measures i.e. control of inlet and outlet flows and setting of the cooking recipe, it will result in the large variations in Kappa number, lower fiber quality or excess use of environmentally harmful cooking chemicals. This becomes particularly important during the swing between softwood and hardwood as part of meeting the final paper product quality requirements. Therefore, a rapid method that is capable of continuous feedstock material characterization is required.Near infrared (NIR) spectroscopy can be used for non-destructive characterization of the feedstock material. In this study, both Fourier transform and grating NIR spectrophotometers were used for NIR absorbance spectra acquisition. Each spectrum was recorded in the range between 700 and 2500 nm. During the calibration of spectra of various wood species with known lignin content, wood samples were placed on a tray so that the tray may move horizontally in a reciprocating manner underneath the sensor while maintaining the constant distance between the sensor and sample. This was done in order to simulate the movement of a real conveyor belt as used for transporting feedstock to the digester. In the on-line application the NIR meter is situated above the conveyor belt that wood up to the digester.Spectral data were pretreated with different methods such as normalization, scatter correction, smoothing, first and second derivative (Savitzky-Golay algorithm), selection of different spectral ranges and its combinations. Mathematical models to estimate lignin content were constructed using Partial Least Square Regression (PLS-R) and Principle component regression (PCR) statistical methods. Response data for model build-up were determined in the chemical laboratory according to standardized procedures including test repetitions. Different combinations of NIR instrument used, pre-treatment methods and statistical methods were evaluated in order to find the model with the best prediction performance.Results are promising and demonstrate that it is possible to characterize the lignin content and reactivity of the feedstock material by NIR spectrophotometers with reasonable prediction model performance. Improved prediction can be obtained if only selected spectral ranges are included as an input for statistical modelling; similarly using derivatives is better than using the raw spectrum. In the next step, developed statistical models for rapid lignin content prediction will be used as a feed-forward input for dynamic process control.

  • 118.
    Skvaril, Jan
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Fast Determination of Fuel Properties in Solid Biofuel Mixtures by Near Infrared Spectroscopy2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 1309-1317Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper focuses on the characterization of highly variable biofuel properties such as moisture content, ash content and higher heating value by near-infrared (NIR) spectroscopy. Experiments were performed on different biofuel sample mixtures consisting of stem wood chips, forest residue chips, bark, sawdust, and peat. NIR scans were performed using a Fourier transform NIR instrument, and reference values were obtained according to standardized laboratory methods. Spectral data were pre-processed by Multiplicative scatter correction correcting light scattering and change in a path length for each sample. Multivariate calibration was carried out employing Partial least squares regression while absorbance values from full NIR spectral range (12,000–4000 cm-1), and reference values were used as inputs. It was demonstrated that different solid biofuel properties can be measured by means of NIR spectroscopy. The accuracy of the models is satisfactory for industrial implementation towards improved process control. 

  • 119.
    Skvaril, Jan
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Fast Determination of Lignin Content in Feedstock Material for Pulping Process Monitoring and Optimization2015Ingår i: ICAVS 8 - Abstracts poster, 2015, s. 556-557Konferensbidrag (Refereegranskat)
    Abstract [en]

    Pulping process is delivering pulp fibers which are further used in the production of paper. The reactor is fed with feedstock material in the form of wood chips. Moreover, cooking chemicals are brought at several points into the reactor. Previous studies have shown that the knowledge of the feedstock material properties which are highly variable is limited. One of the most important parameters is the lignin content, which has to be dissolved, this requires a significant residence time. The residual lignin in the resulting pulp after the process is measured in the form of Kappa number. Inappropriate application of cooking chemicals could lead to large variations in the Kappa number, low fiber quality and other issues. Therefore continuous characterization of the feedstock material is required. One of the available methods for nondestructive characterization of feedstock material is NIR spectroscopy. Presented study is conducted in order to assess the possibility of determining lignin content using NIR method. The spectroscopy workflow consist of four major steps i.e. sample preparation, spectral data acquisition, data pre-processing and multivariate calibration. We used test samples from 13 different tree species, which were tested in the form of wood chips, pulverized wood and mixture of both. Acquired spectral data were pre-processed mainly by second derivative and standard normal variate transformation. PLS regression with full cross validation was used for the development of a calibration model based on selected wavelengths. Acquisition of reference variable has been done according to standardized procedures and it represents the total amount of lignin in the sample.

    The results of lignin characterization in feedstock material by NIR are very promising. The resulting PLS regressionmodel includes 2-factors and uses 16 predicting variables, resulting in R2 = 0,975, RMSE = 0,885 wt%. In the next step, presented work will be improved by applying large amount of samples, independent validation data set and by simulation of conveyor belt movements. The objective of this research is to test the NIR method at a real pulp digester, in order to improve monitoring andoptimization of the process. Furthermore, continuous characterization of the feedstock materials is intended to be used for the improvement of the control process. The measured lignin content will be compared to the content calculated within the pulp digester physical model and the Kappa number. This will be used for improving the digester physical model accuracy and as an input to advanced model based control, where the correlation will be made not only to lignin content but also with the feedstock material reactivity.

  • 120.
    Skvaril, Jan
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Multivariate analysis models for wood properties combined with Open Modelica model for process performance monitoring2015Ingår i: IFAC Proceedings Volumes (IFAC-PapersOnline), 2015, Vol. 48:1, s. 898-899Konferensbidrag (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    To perform advanced model based control it is important to know what is fed into a system such as a waste or biomass fired boiler or a pulp digester. In this paper, we present correlations between the lignin content of different types of wood chips and their Near-infrared (NIR) spectra. The Principal Component Regression (PCR) method is used for deriving the correlation, as well as selecting certain wave lengths. Analysis is made including different parts of the spectra in the wave length range 700 – 2500 nm. The model is then used as input to an Open Modelica pulp digester model to tune the reactivity constant of the dissolution of lignin. The lignin content of wood-chips is determined on-line through the NIR measurement at the feed to the digester. Simulations are carried out to determine the content of residual lignin on fibers at the exit (continuous digester) or at the end of a cook (batch digester). By comparing the deviation between predicted values and actual measured values the reactivity constant of the lignin is determined. The regression can be made to the NIR spectrum aside of the lignin content as such. The original content of lignin together with reactivity may then be used for optimized on-line control of the digester. It can also be used for diagnostic purposes with regard to process issues like hang-ups or channeling, as well as possible sensor faults and data reconciliation.

  • 121.
    Skvaril, Jan
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Avelin, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Rapid Determination of Selected Compounds in Waste-based Fuel by Near Infrared Spectroscopy2015Ingår i: Book of abstracts, 2015Konferensbidrag (Refereegranskat)
    Abstract [en]

    Composition of the waste-based fuel intended for incineration has substantial effect on combustion process performance and formation of environmentally harmful emissions. Fuel composition vary significantly depending on the material source, waste sorting and recycling procedures and other waste pretreatment methods. In general, it typically contains paper, plastics, wood, textile, other organic material and further undesired substances including glass and metals. The knowledge of actual composition of the material fed into the boiler is limited to the direct or indirect continuous moisture content measurements and periodic fuel sampling providing elementary composition. This information is not sufficient for process control and performance optimization, particularly when considering strongly heterogeneous fuel feed. Therefore a rapid and reliable technique for fuel characterization is needed.The work presented here is focused to the quantitative determination of selected plastic materials and glass content. Incomplete combustion of different plastics may lead to the formation of carbon monoxide, hydrogen-cyanides, acid compounds and aromatic hydrocarbons etc. If the waste contains chlorine then highly chlorinated polycyclic compounds such as dioxins and furans may be formed. Plastics often contain flame retardants which can also contribute to production of harmful emissions. On the other hand, the highly corrosive deposits of alkali chlorides and other compounds may be formed on the heat exchangers, this lowers the heat transfer and boiler efficiency and decrease life-time of the equipment. Moreover, increased content of glass in the fuel supports the formation of agglomerates in the fuel bed, defluidization of the bed or ash removal problems which result in malfunction or failure of the combustion equipment.Near infrared (NIR) spectroscopy can be used for non-destructive quantitative determination of plastics and glass in waste-based fuel. Experimental work was performed on two types of spectrophotometers i.e. grating and Fourier transform instruments. Samples of known content of glass and different plastics were placed on a moving tray that reciprocated horizontally back and forth underneath the NIR sensor. This was done in order to replicate online application where the NIR spectrophotometer is places above the conveyor belt that transport the fuel to the boiler.Spectra were recorded in the range between 700 and 2500 nm. Acquired spectral data were pretreated with different methods such as normalization, scatter correction, smoothing, first and second derivative (Savitzky-Golay algorithm), selection of different spectral ranges and its combinations. Mathematical models to estimate content of glass and different plastics were constructed using Partial Least Square Regression (PLS-R) and Principle component regression (PCR) statistical methods. Different combinations of spectrophotometer type, pre-treatment methods and statistical methods were evaluated in order to find the model with the best prediction performance.Results prove the potential of the method to quantitatively determine the content of different types of plastics as well as glass with reasonable prediction accuracy. The ultimate goal of this research is to test the method at a real industrial boiler in order to improve process monitoring and control.

  • 122.
    Skvaril, Jan
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Applications of near-infrared spectroscopy (NIRS) in biomass energy conversion processes: A review2017Ingår i: Applied spectroscopy reviews (Softcover ed.), ISSN 0570-4928, E-ISSN 1520-569X, Vol. 52, nr 8, s. 675-728Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Biomass used in energy conversion processes is typically characterized by high variability, making its utilization challenging. Therefore, there is a need for a fast and non-destructive method to determine feedstock/product properties and directly monitor process reactors. The near-infrared spectroscopy (NIRS) technique together with advanced data analysis methods offers a possible solution. This review focuses on the introduction of the NIRS method and its recent applications to physical, thermochemical, biochemical and physiochemical biomass conversion processes represented mainly by pelleting, combustion, gasification, pyrolysis, as well as biogas, bioethanol, and biodiesel production. NIRS has been proven to be a reliable and inexpensive method with a great potential for use in process optimization, advanced control, or product quality assurance.

  • 123.
    Song, C.
    et al.
    Tianjin University, 92 Weijin Road, Nankai District, Tianjin, China.
    Liu, Q.
    Tianjin University, 92 Weijin Road, Nankai District, Tianjin, China.
    Deng, S.
    Ministry of Education, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kitamura, Y.
    University of Tsukuba, Japan.
    Cryogenic-based CO2 capture technologies: State-of-the-art developments and current challenges2019Ingår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 101, s. 265-278Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    CO2 capture, utilization and storage has been recognized as a primary option to mitigate the issue of climate change caused by the utilization of fossil fuels. Several CO2 capture strategies have been developed, such as absorption, adsorption, membrane, chemical looping, hydrating and biofixation. Among different technologies, particular attention has been given to cryogenic CO2 capture by phase change. The aim of this study is to improve interest in cryogenic technologies for CO2 capture by providing an overview of the actual status of CCS. To reach this goal, the major strategies and technologies for CO2 capture from fossil fuel combustion have been reviewed. Simultaneously, the characteristics of cryogenic technologies for CO2 capture are summarized. The existing challenges that need to be overcome in cryogenic technology include cold energy sources, capture costs and impurities, etc. Finally, opportunities for the future development of cryogenic-based technologies are discussed. The results of this investigation indicated that cryogenic CO2 capture processes can be easily retrofitted to the existing industrial emission facilities and avoid the challenges associated with chemical solvents or physical sorbents. 

  • 124.
    Song, C.
    et al.
    Tianjin University, Tianjin, China.
    Liu, Q.
    Tianjin University, Tianjin, China.
    Ji, N.
    Tianjin University, Tianjin, China.
    Deng, S.
    Ministry of Education, Tianjin, China.
    Zhao, J.
    Ministry of Education, Tianjin, China.
    Li, Y.
    Chinese Academy of Sciences, Tianjin, China.
    Song, Y.
    Tianjin University, Tianjin, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Alternative pathways for efficient CO2 capture by hybrid processes—A review2018Ingår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 82, s. 215-231Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    CO2 capture and storage technologies have been recognized as the primary option to mitigate the issue of climate change caused by the utilization of fossil fuels. In the last decades, several CO2 capture approaches have been developed, such as absorption, adsorption, membrane, cryogenic, hydrate and chemical looping combustion etc. However, the energy penalty is a general challenge for each technology. To overcome the disadvantages of standalone technology, the combination of two or more approaches (namely hybrid CO2 capture processes) has been considered as a potential option. In this work, the status and development of hybrid CO2 capture processes is presented in a classification of primary technology as absorption-based, adsorption-based, membrane-based and cryogenic-based. The detail configuration of each hybrid process is introduced. Simultaneously, the characteristics, advantages and potential challenges of each hybrid process are also summarized. Compared to the standalone methods, hybrid processes showed the superiority not only in CO2 recovery and energy penalty, but also in the installation investment. Therefore, hybrid processes can be a promising alternative to conventional CO2 capture technologies in future.

  • 125.
    Song, Jingjing
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Restructured district heating price models and their impact on district heating users2017Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [sv]

    Fjärrvärme anses som ett effektivt, miljövänligt och kostnadseffektivt sätt för att leverera värme eftersom kraftvärme blir vanligare i fjärrvärmesystem, där elektricitet produceras tillsammans med värme. Den spelar en viktig roll i att begränsa klimatförändringen. Svenska fjärrvärme företag står inför flera utmaningar nu för tiden, och är i akut behov av nya prismodeller för att öka öppenheten och behålla konkurrenskraften.

    I denna avhandling, genomfördes en undersökning för att ta reda på strukturen av de nuvarande prismodellerna. Därefter föreslogs två omstrukturerade prismodeller, vars påverkan på kostnaden av fjärrvärme konsument analyserades jämför med den nuvarande modellen.

    Detta arbete undersökte också effekten av omstrukturerade prismodeller på konsument som skulle drabbas på signifikant kostnadsökning i samband med införande prismodeller. Kostnaden av fjärrvärme under olika prismodeller har också jämförts med tre olika tekniska lösningar.

    Resultatet visade att prismodeller som baserar sig på konsuments förbrukningsprofil kunde återspegla fjärrvärme företagens kostnadsstruktur; Samtidigt medförde prissättningsstrategi baserad på användarens förbrukningsprofil högre incitament för att minska spetseffekt.

    Följaktligen kommer att konsumenter med stabila konsumtionsprofiler att spara kostnader, medan konsumenter med spetsiga konsumtionsprofiler kommer att drabbas av kostnadsökning. Och för den investerade fjärrvärme konsument, den ekonomiska bättre val var att kombinera fjärrvärme med elpanna eller bergvärmepump.

  • 126.
    Song, Jingjing
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Cost comparison between district heating and alternatives during the price model restructuring process2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 3922-3927Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    District heating (DH) has been considered as a resource- and cost-efficient way of supplying heat and a promising method to mitigate climate change, yet it also facing growing competition from alternative technical solutions, such as heat pumps. Many DH companies are under price model restructuring process to enhance their competitiveness. This study investigated the competitiveness of DH among users which would encounter significant cost increase during the price model restructuring process through comparing the cost of different DH price models with three alternative technical solutions. The result shows that for the invested DH user, instead of DH, the most economic preferable choice is to install ground source heat pump combining with direct electrical heating.

  • 127.
    Song, Jingjing
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    District heating cost fluctuation caused by price model shift2017Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 194, s. 715-724Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    District heating companies are facing multiple challenges nowadays, including increased investment and maintenance cost and critique from customers regarding opaque price model. Hence there is an urgent need to develop new price models. In this paper, a survey was carried out and identified four basic components in the price model. Three price models that represent the current situation and future trend have been extracted from the survey as well. Based on those price models, investigation was performed to study the impacts of different components in price models on customers’ cost. The result shows that customers with flatter consumption profiles can benefit from the price model that has a higher share of load demand component and use consumers’ real-time consumption data for charging. On the contrary, when a price model that has a higher share of energy component is adopted, customers with flatter consumption profiles may experience an increase in the cost.  

  • 128.
    Song, Jingjing
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Effectiveness of introducing heat storage to repress cost increase2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    District heating companies have been adapting their price models to reflect the changes in production cost caused by penetration of renewable fuels, and promote the applications of energy conservation measures that benefit the system efficiency. One of the approaches is to introduce a peak demand component in the price model, which has been proved to be effective to benefit users with lower peak demand. Whereas, this approach also significantly increase the cost for users with high peak demand. One of the measures that could help with high peak demand is installing energy storage on the demand side. In order to understand how the energy storage could change the users’ cost and help DH users to make informed decision, this study analyses the economic benefits of demand-side heat storage, namely if installing low-investment, low-tech, short-term hot-water storage on demand side could effectively repress the cost increase caused by new price models. Five types of building are considered here: multifamily house, commercial building, hospital and social services, industrial building, and office and school. One user of each type, whose costs increased the most during the price model transition process have been included. The result shows that heat storage could efficiently repress the cost increase, and all the investments will be paid back within 3 years, which means introducing heat storage is an efficient measure for cost saving under the circumstances.

  • 129.
    Song, Jingjing
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Karlsson, Björn
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Price models of district heating in Sweden2016Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 88, s. 100-105Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Traditional pricing scheme of district heating is based on previous experience of system operation. This strategy does not work well under the circumstances of decreasing demand and shifting consumption pattern. Therefore new pricing strategies are needed. To have a comprehensive view on existing price models in Sweden, a price model survey was carried out among all members of the district heating quality system REKO. Four basic price components and multiple variants of them are detected in the survey. The result also shows that most of the district heating companies still use traditional methods and do not consider their customers’ consumption pattern while charging them.

  • 130.
    Stigson, Peter
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Dotzauer, Erik
    Yan, Jinyue
    Policy evaluation according to relative industrial performance and competitiveness2008Konferensbidrag (Refereegranskat)
  • 131.
    Stigson, Peter
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. IVL Swedish Environmental Research Institute, Stockholm, Sweden.
    Roth, Susanna
    IVL Swedish Environmental Research Institute, Stockholm, Sweden.
    Karlsson, Anja
    IVL Swedish Environmental Research Institute, Stockholm, Sweden.
    Re-Evaluating the Sustainability of Energy Systems: The Nexus of Energy, Water, and Land-Use2014Ingår i: Handbook of Clean Energy Systems / [ed] Jinyue Yan, John Wiley & Sons, 2014, 1, s. 1-14Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    Scenarios for global developments typically point to a sharp increase in demand for energy as well as for water and land. These developments have a starting point where global ecosystems are already being exploited unsustainably. This has implications for energy systems, which can be designed as more or less water and land-use intensive. However, evaluating the sustainability of energy systems commonly do not take water and land-use systems into account. This presents a problem as these three systems—energy, water, land—are intrinsically linked, which provides both barriers and opportunities for these systems' individual as well as collective sustainability. More comprehensive evaluations of energy systems that acknowledge the system interlinkages are therefore needed. This has become known as applying a nexus approach. The idea behind the nexus approach is to increase system synergies and resilience through jointly analyzing ecosystem capacities, drivers for resource use, development objectives, capacities to manage linked systems, and the need for new knowledge. This provides a comprehensive perspective on the restrictions and freedom we have in governing, designing, and using the social, technical, and ecological systems. The article thus presents a nexus approach and provides an understanding of challenges for the sustainability of energy systems from a broad system perspective.

  • 132.
    Stigson, Peter
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Stigson, Björn
    Promoting Eco-Industrial Parks in China: Policy suggestions for voluntary agreements2007Ingår i: 3rd International Green Energy Conference: Proceedings of IGEC-III, 2007, 2007, s. 1273-1283Konferensbidrag (Refereegranskat)
    Abstract [en]

    China has in later years experienced a rapid economic development, which has occurred at the expense of the

    environment. This strongly applies to the manufacturing industry as a central element in the developing economy.

    The Chinese government is however now pursuing a development path associated with improved environmental

    characteristics with a focus on Resource and Energy Efficiency (R&EE). Within this development Eco-Industrial

    Parks (EIPs) can make an important contribution for improved R&EE in the manufacturing industry. EIPs facilitate

    low energy and environmental impact production and the concept consequently comply both with economic and

    ecologic development goals, while also having social benefits. While EIPs are promoted in the Chinese general

    policy framework, such as the Circular Economy (CE), they are not targeted by any specific policy instruments.

    Based on a review of international and Chinese policy recommendations and experiences on R&EE policy, the

    paper identify that this can be effectively accomplished by Voluntary Agreements (VAs). A positive aspect of VAs is

    the design flexibility that allows the instrument to be adapted to the varying conditions under which Industrial Parks

    (IPs) operate in China. VAs are also identified to encompass a number of positive features in the China EIP case

    as regards to increasing policy compliance, accomplishing short-term results, avoiding inefficient technological

    lock-in as part of the rapid development, contributing to capacity building, and dealing with EIP management

    barriers.

  • 133.
    Swing Gustafsson, Moa
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Mälardalens Högskola.
    Heating of buildings from a system perspective2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Energy efficiency measures in buildings are considered to have great potential for reducing total energy use, and contribute to a reduced climate and environmental impact. In Sweden, however, there is a focus on bought energy, which does not always reflect the environmental and climate impact. Focusing on bought energy means that a house owner may choose an electricity based heat pump instead of district heating (DH), since heat pumps result in less bought energy compared to DH.

    The energy system surrounding the buildings is affected by the choice of energy carriers used for heating. This thesis uses three different methods to study how the energy system is affected. In the first part, primary energy use has been calculated for a simulated building with different heating systems, resulting in different electricity and DH demands. The second part studies the impact on peak demand and annual consumption in the power grid and DH system due to different market shares of electricity based heating and DH. In the third part, the life cycle cost is calculated for different heating solutions from both a building and a socio-economic perspective, for 100 % renewable energy system scenarios.

    The results show that the choice of energy carrier has a great influence on primary energy use. However, this depends even more on the calculation method used. Which heating solution, and thus which energy carrier, gives the lowest primary energy use varies with the different methods.

    The power grid and DH system are affected by the choice of energy carrier. There is a potential to lower peak demand in the power grid by more efficient heat pumps. But an even greater potential is shown by using DH instead of electricity based heating. A larger share of DH also allows the production of more electricity with the use of combined heat and power.

    The life cycle cost for different heating solutions also depends on the method used. From a building owner’s perspective, with current electricity and DH prices, electricity based heating is more economical. However, from a socio-economic perspective, with increasing electricity system costs due to a larger share of variable electricity production in a 100 % renewable system, DH becomes more economically profitable in several scenarios.

    The choice of energy carrier for heating in buildings affects the energy system to a high degree. A system perspective is therefore important in local, national and global energy efficiency policies and projects.

  • 134.
    Swing Gustafsson, Moa
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Dalarna University, Sweden.
    Myhren, J. A.
    Dalarna University, Sweden.
    Dotzauer, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Gustafsson, M.
    Linköping University, Sweden.
    Life cycle cost of building energy renovation measures, considering future energy production scenarios2019Ingår i: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 12, nr 14, artikel-id 2719Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A common way of calculating the life cycle cost (LCC) of building renovation measures is to approach it from the building side, where the energy system is considered by calculating the savings in the form of less bought energy. In this study a wider perspective is introduced. The LCC for three different energy renovation measures, mechanical ventilation with heat recovery and two different heat pump systems, are compared to a reference case, a building connected to the district heating system. The energy system supplying the building is assumed to be 100% renewable, where eight different future scenarios are considered. The LCC is calculated as the total cost for the renovation measures and the energy systems. All renovation measures result in a lower district heating demand, at the expense of an increased electricity demand. All renovation measures also result in an increased LCC, compared to the reference building. When aiming for a transformation towards a 100% renewable system in the future, this study shows the importance of having a system perspective, and also taking possible future production scenarios into consideration when evaluating building renovation measures that are carried out today, but will last for several years, in which the energy production system, hopefully, will change.

  • 135.
    Söder Altschul, Joakim
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Karlsson, Tomas
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    ENERGIEFFEKTIVISERING AV INDUSTRIELLA VERKSAMHETER: Värderingar grundade i ekonomiska, miljö- och sociala aspekter för GKN ePowertrain, Köping2019Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    To decrease the ecological footprint, humans either have to adjust their lifestyles, or the large scale industries must take corporate social responsibility. This study is based on the well-developed field of energy efficiency in industries by applying technology and organizational-focused proposals. The proposals are based on three different aspects, the economic, the environmental, and the social. These three aspects combined are called the triple bottom line perspective. An original case of the study objects energy balance was determined to develop the conclusions, with the simulation program IDA ICE. The study object was GKN ePowertrain, located in Köping. Energy efficiency cases were simulated in IDA ICE to observe the change in the energy balance. The cases and interviews of the employees were the foundation of the discussion where the improvements were critically reviewed from the triple bottom line perspective. The result shown that the temperature was too high for working conditions, the ventilation system consumes a large quantity of energy, and the internal flow of information is insufficient. In conclusion, GKN ePowertrain would increase their overall value by investing in a cooling system and more efficient heat exchangers for their ventilation system. These investments would notably increase their short term value of environmental sustainability and the social aspect. Furthermore, their economic value would increase in the long term. The cooling system would improve the working environment, and a new ventilation system would increase the heat recovery and decrease the energy consumed, even more than the consumption of the cooling system. Finally, GKN should also be more distinct in their information to the employees in the building regarding energy aims and their working environment, to have a positive gain of value in all the fields.

  • 136. Tan, Y.
    et al.
    Nookuea, Worrada
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, China.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. School of Chemical Science and Engineering, Royal Institute of Technology, Stockholm, Sweden.
    Impacts of thermos-physical properties on plate-fin multi-stream heat exchanger design in cryogenic process for CO2 capture2019Ingår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 149, s. 1445-1453Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Oxy-fuel combustion is one of the most promising technologies for CO2 capture for power plants. In oxy-fuel combustion plants, cryogenic process can be applied for CO2 purification because the main impurities in flue gas are non-condensable gases. The multi-stream plate-fin heat exchanger is one of the most important components in the CO2 cryogenic system. In-depth understanding of the impacts of property on the heat exchanger is of importance for appropriate design. In order to investigate the impacts of properties on sizing the heat exchanger and to further identify the key properties to be prioritized for the property model development, this paper presented the design procedure for the plate-fin multi-stream heat exchanger for the CO2 cryogenic process. Sensitivity study was conducted to analyze the impacts of thermos-physical properties including density, viscosity, heat capacity and thermal conductivity. The results show that thermal conductivity has the most significant impact and hence, developing a more accurate thermal conductivity model is more important for the heat exchanger design. In addition, even though viscosity has less significant impact compared to other properties, the larger deviation range of current viscosity models may lead to higher uncertainties in volume design and annual capital cost of heat exchanger. 

  • 137.
    Tao, J.
    et al.
    North China Electric Power University, Beijing, China.
    Lu, Q.
    North China Electric Power University, Beijing, China.
    Dong, C.
    North China Electric Power University, Beijing, China.
    Du, X.
    North China Electric Power University, Beijing, China.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Effects of electric current upon catalytic steam reforming of biomass gasification tar model compounds to syngas2015Ingår i: Energy Conversion and Management, ISSN 0196-8904, E-ISSN 1879-2227, Vol. 100, s. 56-63Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Electrochemical catalytic reforming (ECR) technique, known as electric current enhanced catalytic reforming technique, was proposed to convert the biomass gasification tar into syngas. In this study, Ni-CeO<inf>2</inf>/γ-Al<inf>2</inf>O<inf>3</inf> catalyst was prepared, and toluene was employed as the major feedstock for ECR experiments using a fixed-bed lab-scale setup where thermal electrons could be generated and provided to the catalyst. Several factors, including the electric current intensity, reaction temperature and steam/carbon (S/C) ratio, were investigated to reveal their effects on the conversion of toluene as well as the composition of the gas products. Moreover, toluene, two other tar model compounds (benzene and 1-methylnaphthalene) and real tar (tar-containing wastewater) were subjected to the long period catalytic stability tests. All the used catalysts were analyzed to determine their carbon contents. The results indicated that the presence of electric current enhanced the catalytic performance remarkably. The toluene conversion reached 99.9% under the electric current of 4 A, catalytic temperature of 800 °C and S/C ratio of 3. Stable conversion performances of benzene, 1-methylnaphthalene and tar-containing wastewater were also observed in the ECR process. H<inf>2</inf> and CO were the major gas products, while CO<inf>2</inf> and CH<inf>4</inf> were the minor ones. Due to the promising capability, the ECR technique deserves further investigation and application for efficient tar conversion.

  • 138.
    Thorin, Eva
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Ahrens, Thorsten
    Ostfalia University.
    Hakalehto, Elias
    University of Eastern Finland.
    Jääskeläinen, Ari
    Savonia University of Applied Sciences.
    Organic waste as a biomass resource2013Ingår i: Biomass as Energy Source: Resources, Systems and Applications / [ed] Erik Dahlquist, CRC Press, 2013, s. 109-133Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 139.
    Thorin, Eva
    et al.
    Mälardalens högskola, Institutionen för samhällsteknik.
    Brand, Heike
    University of Stuttgart, Germany.
    Weber, Christoph
    University of Stuttgart, Germany.
    Long-term Optimization of Cogeneration Systems in a Competitive Market Environment2005Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 81, nr 2, s. 152-169Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A tool for long-term optimization of cogeneration systems is developed that is based on mixed integer linear programming and Lagrangian relaxation. We use a general approach without heuristics to solve the optimization problem of the unit commitment problem and load dispatch. The possibility to buy and sell electric power at a spot market is considered as well as the possibility to provide secondary reserve. The tool has been tested on a demonstration system based on an existing combined heat and power (CHP) system with extraction-condensing steam turbines, gas turbines, boilers for heat production and district heating networks. The key feature of the model for obtaining solutions within reasonable times is a suitable division of the whole optimization period into overlapping subperiods. Using Lagrangian relaxation the tool can be applied to large CHP systems. For the demonstration model almost optimal solutions were found.

  • 140.
    Thorin, Eva
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Daianova, Lilia
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Guziana, Bozena
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Wossmar, Susanne
    Handelskammaren Mälardalen.
    Degerfeldt, Viveka
    Handelskammaren Mälardalen.
    Granath, Lennart
    Länsstyrelsen Västmanland.
    CURRENT STATUS OF THE WASTE- TO- ENERGY CHAIN IN THE COUNTY OF VÄSTMANLAND, SWEDEN2011Rapport (Övrig (populärvetenskap, debatt, mm))
  • 141.
    Thorin, Eva
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Daianova, Lilia
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Lindmark, Johan
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Nordlander, Eva
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Song, Han
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Jääskeläinen, Ari
    The Municipal Federation of Savonia University of Applied Sciences.
    Malo, Laura
    Centre for Economic Development, Transport and the Environment for North Savo (CNS).
    den Boer, Emilia
    Institute of Environment Protection Engineering, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
    den Boer, Jan
    WAMECO S.C., ul. Malinowa 7, 55-002 Kamieniec Wrocławski, Poland.
    Szpadt, Ryszard
    Institute of Environment Protection Engineering, Wrocław University of Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
    Belous, Olga
    Klaipeda University (KLU).
    Kaus, Taivo
    Estonian Regional and Local Development Agency (ERKAS).
    Käger, Marja
    Estonian Regional and Local Development Agency (ERKAS).
    State of the art In the Waste to Energy Area: Technology and Systems2011Rapport (Övrigt vetenskapligt)
  • 142.
    Thorin, Eva
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Guziana, Bozena
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Song, Han
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Jääskeläinen, Ari
    The Municipal Federation of Savonia University of Applied Sciences .
    Szpadt, Ryszard
    Wroclaw University of Technology / Institute of Environmental Protection Engineering.
    Vasilic, Dejan
    Ostfalia University of Applied Sciences, Fachhochschule Braunschweig / Wolfenbüttel.
    Ahrens, Thorsten
    Ostfalia University of Applied Sciences, Fachhochschule Braunschweig / Wolfenbüttel.
    Anne, Olga
    Klaipeda University .
    Lõõnik, Jaan
    Estonian Regional and Local Development Agency (ERKAS).
    Potential future waste-to-energy systems2012Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This report discusses potential future systems for waste-to-energy production in the Baltic Sea Region, and especially for the project REMOWE partner regions, the County of Västmanland in Sweden, Northern Savo in Finland, Lower Silesia in Poland, western part of Lithuania and Estonia.

    The waste-to-energy systems planned for in the partner regions are combustion of municipal solid waste (MSW) and solid recovered fuels from household and industry as well as anaerobic digestion of sewage sludge and agriculture waste.

    The potential future waste-to-energy systems in the partner regions include increased utilization of available waste resources. Examples of resources possible to use are straw that could be used for ethanol production and biowaste from households and manure that could be used for biogas production. If the utilization in all partner regions would reach the same level as already exists in the County of Västmanland it would correspond to an increased energy supply of 3 TWh/year which corresponds to about 2.5 % of the total energy use in the partner regions year 2008.

    An important aspect of future anaerobic processes for biogas production is the possibility to use the residue. West Lithuanian biogas production residue is planned to be dewatered up to 90 % of dry matter to make future utilization options possible.

    Pre-processing is necessary to be able to use the residue from digestion of solid waste as fertilizer. The pre-processing should include crushing, removal of metals, wood and plastics, and pulping. Without pre-processing it is possible to combust the residues with energy utilisation. Results from an investigation of the residues from biogas production tests using substrates from the project partner regions show a remaining energy potential of the digestate corresponding to 17 to 50% of the biogas energy. A combination of digestate combustion and fertilizer use could be a possibility.

    Hydrothermal carbonization, HTC, is a process that could be of interest to use for treating digestate in order both to utilize the energy left after biogas production but also for sanitation of the digestate. In this process heat is released and coal is produced. This process could also be of interest for waste-to-energy conversion of waste which is usually not usable for other biological process like e.g. biogas production, for example sharp leaved rush, straw or leaves from gardening etc. Initial tests on pulp and paper waste show promising results.

    Among the possible processes for increasing the output of biogas from anaerobic digestion using ultrasound technology for thickening of surplus waste water sludge can be mentioned. It allows increasing the biogas production up to 30 % and reducing the amount of organic substances in the digested sewage sludge by up to 25 %. Another area of possible improvement is the mixing in the digester. The mixing is important for distribution of microorganisms and nutrition, inoculation of fresh feed, homogenizing of the material and for the removal of end products of the metabolism. Studies of the digester for biowaste in the County of Västmanland indicate that about 30 % of digester volume can have dead and stagnant zones.

    2

    Waste-to-energy utilisation could also be possible to realise by further development and introduction of new processes and concepts. An option for solving the problem of old sewage sludge could be to use it in a gasifier to convert it to energy rich gases. Microbiological conversion of waste can be further developed to produce several different products, such as heat, power, fuels and chemicals, the development of so-called biorefineries. Also the biorefinery‘s water management can be renewed in order to remove toxic substances, minimize environmental impacts and produce pure, clean water. Finnoflag Oy has developed a technology that converts waste materials into e.g. fuels, chemicals, plastic and rubber via low-energy routes. The Finnoflag technology is based on the PMEU (Portable Microbe Enrichment Unit) which is a new innovative instrument for use in the microbe detection process and that is designed to create an optimal growth environment for microbes.

    For fibrous and well-structured biowaste dry digestion could be a good option for biogas production. Several different configurations have been tested in Germany. The garage digestion method has the advantage that an extensive pre- treatment of substrate is not necessary and no pumps or stirrers, which can be destroyed by disturbing materials, are involved. However, the efficiency of garage digesters is low compared to other digestion methods due to lack of effective substrate turbation. More research work is needed to improve the efficiency. Tests of five existing dry digestion processes show that the Tower-digester is the most suitable dry digestion method for household waste. Among the reviewed plants the Dranco-tower digester showed the best efficiency in reference to biogas potential. The plant design is robust enough to handle substrates like household waste with fractions of disturbing materials. The mixing in the reactor is based on the force of gravity and the used pumps are powerful and very resistant.

    Pyrolysis is a process of interest for converting wood based waste into energy products such as gas, bio-oil and/or solid fuel/carbon. This has been identified as a process suitable for a new business model with a franchise based model, offering an earning opportunity for small size entrepreneurs.

    Possible improvement of existing and new waste-to-energy systems also includes increasing the overall efficiency of the utilization of waste resources by integration of several processes. A study on integrating pellets production from the residues from straw-based ethanol production with an existing combined heat and power plant shows that the total production cost can be reduced by the integration.

    Possible development of waste-to-energy systems for the partner regions could be the following:

     Estonian - biogas production using the organic waste, use of the digestate as fertilizer on demand or combustion for power and heat production, recycling plants for paper, plastics and other recyclable wastes and combustion for power and heat production after recycling

     North Savo, Finland- the same options as for Estonia is of interest. Added to this is the potential for power and heat production from large amount of wood waste. Also the possibility for pellet production from wood waste could be of interest.

     Western Lithuania- the same system as mentioned for Finland is also of interest for western Lithuania.

    3

     

     Lower Silesia, Poland- also for Lower Silesia high amounts of organic wastes is suitable to use for biogas production in anaerobic digestion. Recovered derived fuel (RDF) is already used as fuel for power and heat production. There are also some attempts to involve combustion of residual mixed waste in 1-2 of the most densely populated areas.

     County of Västmanland, Sweden- Here a system for separate collection of the biowaste from households, digestion of the fraction together with ley crop silage from regional farmers to produce biogas and use of the digestate from the digestion process as fertilizer at farmland already exists and a new power and heat plant using recovered derived fuels is under construction. Further waste- to-energy plants for production of bioethanol from straw and biogas from agricultural waste could be possible.

    The potential future waste-to-energy systems are not only dependent on available technologies for waste-to-energy conversion but also on the development within the waste and energy areas including also economic and political aspects. There is a growing interest for waste prevention in waste management within the EU, and growing concern about food losses and food waste at global and national levels. During past decades the waste amounts have steadily increased with economic growth but due to waste prevention actions a decoupling of the waste amount and economic growth is foreseen. This has to be considered in development of future waste-to-energy systems. Further, policies and goals concerning fossil fuel free transportation systems and low carbon energy systems is of importance.

    Analysis of combined previous proposed scenarios for energy demand and use development and waste amount development for waste-to-energy in Sweden 2010 to 2050 shows that the contribution of waste-to-energy to the total energy supply in 2050 varies from 6 to 47 % depending on the scenarios combined. The lowest contribution occur for scenarios with low waste amounts combined with energy scenarios with low changes in energy demand while the highest contribution occurs for scenarios with high amount of waste combined with energy scenarios with large decrease in energy demand.

  • 143.
    Thorin, Eva
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Nordlander, Eva
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Lindmark, Johan
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Bel Fdhila, Rebei
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    MODELING OF THE BIOGAS PRODUCTION PROCESS- A REVIEW2012Konferensbidrag (Refereegranskat)
    Abstract [en]

    Production of biogas by digestion of organic wastes and other feedstock is one of the important technical solutions that contribute to the transform of the energy system from being fossil fuel dependent to renewable energy originated. To be fully commercial and competitive, the production of biogas needs to be further developed and optimized based on the technical, economic and environmental aspects. Thus, comprehensive understanding of fluid dynamics and microbial reactions in the digestion process is necessary to accurately and robustly model, predict and control the biogas production.

    In this paper possible pathways for modeling the biogas reactor is discussed based on previous work on anaerobic digestion modeling and modeling of the fluid flow in reactors. Important parameters for modeling biogas production, with a focus on processes using waste as feedstock, are considered. Identification of knowledge gaps for the modeling of the biogas process is performed and how to overcome the obstacles is addressed.

  • 144.
    Thygesen, Richard
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Karlsson, Björn
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Simulation of a low energy building in Sweden with a high solar energy fraction.2012Ingår i: PassivhusNorden / [ed] Lasse Postmyr, Tapir Akademisk Forlag, 2012Konferensbidrag (Övrigt vetenskapligt)
  • 145.
    Vassileva, Iana
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Campillo, Javier
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Consumers' Perspective on Full-Scale Adoption of Smart Meters: A Case Study in Vasteras, Sweden2016Ingår i: Resources, E-ISSN 2079-9276, Vol. 5, nr 1, artikel-id 3Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Large-scale deployment of reliable smart electricity metering networks has been considered as the first step towards a smart, integrated and efficient grid. On the consumer's side, however, the real impact is still uncertain and limited. This paper evaluates the consumer's perspective in the city of Vasteras, Sweden, where full implementation of smart meters has been reached. New services, such as consumption feedback and the possibility to choose dynamic electricity pricing contracts, have been available from the adoption of this infrastructure. A web-based survey evaluating customers' perception of these new services was carried out. The survey included consumers' personal information, preferences about the type of information and the frequency of delivery and the preference for electricity pricing contracts. The results showed that the electricity consumption information offered by distribution system operators (DSOs) today is not detailed enough for customers to react accordingly. Additionally, while variable pricing contracts are becoming more popular, the available pricing schemes do not encourage customers to increase their consumption flexibility. Therefore, more detailed information from the smart meters should be made available, including disaggregated electricity consumption per appliance that would allow consumers to have more control over their energy consumption activities.

  • 146.
    Vassileva, Iana
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Campillo, Javier
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Eskilstuna (Sweden) as an example of a smart city from an energy efficiency perspective.2014Konferensbidrag (Refereegranskat)
  • 147.
    Vassileva, Iana
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thygesen, Richard
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Campillo, Javier
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Schwede, Sebastian
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    From Goals to Action: The Efforts for Increasing Energy Efficiency and Integration of Renewable Sources in Eskilstuna, Sweden2015Ingår i: Resources, E-ISSN 2079-9276, Vol. 4, nr 3, s. 548-565Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Cities’ energy usage accounts for two thirds of global primary energy consumption. Energy efficiency in urban areas is, therefore, one of the most important topics to consider when dealing with urban sustainability. This paper evaluates the goals for increasing energy efficiency and use of renewable energy sources in the areas of transportation, buildings and consumers’ awareness, as stated in the Climate action plan, for the municipality of Eskilstuna, Sweden. The efforts of the municipality to successfully reach their energy efficiency goals, are described in this paper including future perspectives. The results show that although the municipality counts with the advantage of owning and working together with the local housing company and energy provider, in order to reach the established goals, additional strategies need to be considered. For an increased use of renewable energy sources, analysis of rooftops suitable for photovoltaic (PV) installation should be carried out as well as the integration of goals for self-consumption. In the transport field, the city needs to prepare for large-scale electric vehicle (EV) market penetration and to consider different bike or car sharing options. Finally, more specific awareness campaigns are needed to engage the citizens in reducing their energy consumption and living a more sustainable life.

  • 148.
    Vera Ibanez, Anatole
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Snökyla för is och komfort: Möjligheter att använda snö för komfortkyla och isproduktion vid Rocklundas idrottsarenor2017Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The idea of snow cooling in this case is to save snow from winter to summer and to use it for air conditioning and for saving energy in the production of ice in hockey arenas. Today in Sweden, snow power on a large scale is used only on one place, the hospital in Sundsvall. There you’ll find a pond with 70 000 m3 of snow. The melt water in the pond is heated up while cooling down warm air from the hospital, before circulating back to the pond where it regains a low temperature passing through the snow. The idea was to examine the possibility to use such a system in Västerås, at the multiple sports arenas at Rocklunda, partly for air conditioning and partly for ice production. This work was made possible through gathering information on snow storage and on the Sundsvall snow cooling plant, by interviewing people with insight in the Sundsvall hospital and Rocklunda sports arenas and by calculating the electricity consumption, necessary amount of snow and making an LCC-analysis. For air conditioning the melt water would be used like in Sundsvall but for ice production the melt water would be used for condensing the cooling media in the heat pump at a lower temperature then it would do while cooling with air or river water during summer. Annual electricity savings of 120 and 154 MWh for the arenas were made for 2016 and 2017 when using the snow for ice production. For the air conditioning the saving were estimated to around 55 MWh per year. A snow dispatch hatch in one of the hockey arenas made an alternative to a full-scale snow cooling system. Using this hatch for temporal snow power could save up to 62 MWh per year when used for ice production and 38 MWh when used for air conditioning. The estimated costs for construction of said system proved to be too expensive for making a full-scale snow power system a reality. For ice production a storage of 103 000 m3 of snow was needed which made for a result of -57 MSEK in the LCC-analysis. For the air conditioning alone, a storage of 6 000 m3 was needed which made for a result of -4.2 MSEK. The snow dispose hatch, even without the need of snow storage, resulted in -5.9 MSEK for ice production and -1.6 MSEK for air conditioning. With more thoroughly estimations of the investment costs, together with global warming and thus bigger potential for saving energy, this might be a promising investment in the future.

  • 149.
    Wang, C.
    et al.
    Luleå University of Technology, Luleå, Sweden.
    Larsson, M.
    MEFOS - Metallurgical Research Institute AB, Luleå, Sweden.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Dahl, J.
    Luleå University of Technology, Luleå, Sweden.
    CO2 emission reduction in the steel industry by using emission trading programs2007Ingår i: International Journal of Green Energy, ISSN 1543-5075, E-ISSN 1543-5083, Vol. 4, nr 5, s. 505-518Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The implementation of the EU Emission Trading Scheme ( ETS) started on January 1(st) 2005 according to national plans for allocating emissions rights. The steel industry is one of the industrial sectors included in this scheme. The objective of this paper is to investigate and evaluate the optimum solution( s) for European steel plants to meet their emission allowance with low reduction cost. An optimization model based on a Swedish steel plant is developed and used. Three scenarios were created in the model, i. e., internal changes within the steel plant, EU ETS, and the Kyoto Protocol's clean development mechanism ( CDM). For the last scenario, China was selected as a country of the non- Annex I Party for the emission trading by CDM. The modeling results show that the studied plant will face an emission gap between allowed and calculated emissions in the near future. Compared to EU ETS, the implementation of CDM projects will make the plant reduce CO2 emissions at a lower cost. The internal changes within the plant will also play an important role for the solution of low abatement cost. The model developed could serve as a benchmark for the future emission trading simulation's purpose within the European steel industry.

  • 150.
    Wang, C. S.
    et al.
    Tianjin Univ, Key Lab Smart Grid, Minist Educ, Tianjin 30072, Peoples R China..
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Inst Technol, Sch Chem Sci & Engn, S-10044 Stockholm, Sweden..
    Jia, H. J.
    Tianjin Univ, Key Lab Smart Grid, Minist Educ, Tianjin 30072, Peoples R China..
    Wu, J. Z.
    Cardiff Univ, Sch Engn, Cardiff CF24 3AA, S Glam, Wales..
    Yu, J. C.
    State Grid Tianjin Elect Power Co, Tianjin 300010, Peoples R China..
    Xu, T.
    Tianjin Univ, Key Lab Smart Grid, Minist Educ, Tianjin 30072, Peoples R China..
    Zhang, Y.
    Malardalen Univ, Sch Sustainable Dev Soc & Technol, S-72123 Vasteras, Sweden..
    Renewable and distributed energy integration with mini/microgrids2019Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 237, s. 920-923Artikel i tidskrift (Övrigt vetenskapligt)
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