Design of a secondary combustion chamber for a 350 kW wood-chips Gred furnace.

Abstrac

Long-term sustainability assessment of fossil-free fuel production concepts

The number of possible combinations of feedstock, feedstock pre-treatment, and downstream processes for large-scale production of different types of biofuel is substantial. Different productionroutes will obviously perform very differently with respect to profitability and carbon footprint. Furthermore, large-scale production of biofuels requires substantial strategic investment decisions, requiring a prospective assessment approach. Evaluation of future biorefinery concepts using today’s conditions can be heavily misleading, and it is therefore essential that possible future conditions and related uncertainties are taken into account. This work explores methodological choices and assumptions of Techno-Economic Assessment (TEA) and Life Cycle Assessment (LCA) methods and tools used in four research groups in Sweden for assessing the long-term economic and carbon footprint performance of large future biorefinery concepts.The report presents an in-depth analysis of the methods and tools used in the participating groups, and clearly establishes the need for increased collaboration and data exchange between biorefinery process developers, value chain modellers, TEA and LCA practitioners and large-scale energy and material system modellers. The work presented constitutes a significant step in this direction by clearly establishing the potential strength of prospective TEA and LCA in combination with scenarios describing possible future developments of the background energy system in which future biofuel production systems will operate. The report presents new results for one of the bio-methane production routes investigated in the “METDRIV - Methane as vehicle fuel – a well-to-wheel analysis” study conducted by B\uf6rjesson et al (2016) with respect to energy, greenhouse gas emissions (GHG) and cost performance. The input data used in the original METDRIV study were based on average prices/costs and GHG emission factors valid at the time of the study. In this work, new input data is adopted that reflects possible energy market development pathways generated by the ENPAC energy market scenario tool developed at Chalmers. For the selected production route, the results show that assumptions for costs and greenhouse gas emission factors related to increased use of biomass are of utmost significance, and that there is a clear need for further work in this area.Finally, the report discusses some of the major challenges that remain to be addressed when developing scenarios for the “background” energy system to be used in prospective assessment studies of future biorefinery concepts:Handling the possible consequences of future limited biomass availability on biomass feedstock prices and emission factors.Handling future development of the electric power grid, as well as other large-scale grid energy systems (e.g. district heating) in a carbon-constrained worldIntegration issues: large-scale biorefinery concepts are likely to be co-located at existing industrial sites, which will also evolve in reaction to policy instruments, thereby affecting opportunities for integration of material and energy flows

Effekt på värdeutfallet av sågad vara vid övergång från 30 till 60 cm moduler : - en fallstudie av Moelven

The purpose of this study is to explain how the value of sawn wood changes when sawn wood are cut in 30 respective 60 cm lengths. The raw material into the saw mill will mainly be bucked in 30 cm and 60 cm modules. There will also be two alternatives where the timber will be bucked special lengths, 370, 490 and 550 cm but also in 490 and 550 cm. The method used for the study is to simulate both cutting and sawing the woods. For cutting the simulator Timan is used and for sawing the simulator Timberopt is used. When data is generated from the simulators, calculations of some key figures is done and also how much the revenue need to be increased for the sawn wood in order to cover for the increased costs of changing sawn wood from 30 cm to 60 cm modules The conclusion is that the single biggest reason, impacting the value of the sawn wood is the cutting at the saw mill. When going from 30 to 60 cm modules, the impact will be that the customers to the saw mill must pay more to increase the revenue by at least 10% for the sawn wood in order to justifice the change in production. It is also possible to increase the value of the products further by bucking the timber in three lengths, 370, 490 and 550 cm, in order to get 12 % increase of the share of longer sawn wood (>= 480 cm).Syftet med studien är att förklara hur värdet på sågad vara förändras när den avkapas i 30 respektive 60 cm moduler. Råvaran in till sågverket kommer huvudsakligen att apteras i 30 cm respektive 60 cm moduler. Det kommer också att finnas två alternativ där timret apteras i speciallängderna 370, 490 och 550 cm, samt 490 och 550 cm. Metoden som användes i studien är att simulera såväl aptering som avkapning. För aptering i skogen användes simulatorn Timan. För sönderdelning och avkap på sågverket användes simulatorn Timberopt. När data genererats från simulatorerna har också beräkning av vissa nyckeltal gjorts, samt beräkningar på hur mycket intäkterna för den sågade varan behöver öka för att täcka värdeminskningen av en omläggning av sågad vara från 30 cm till 60 cm moduler. Slutsatsen är att den största, enskilda posten till minskat värde uppstår vid avkapet i justerverket. Vid en övergång från 30 cm till 60 cm moduler, blir konsekvensen att kunderna till sågverket måste vara beredda att betala minst 10% mer för att täcka värdeminskningen vid omläggning till 60 cm moduler. Det är också möjligt att öka värdet på produkten ytterligare genom att aptera timret i två långa och en kort längd, dvs 370, 490 och 550 cm. Då fås en ökning med ca 12% av sågad vara som överstiger 480 cm i längd

Emotional intelligence, need for cognition and cognitive reflective ability related to attitudes towards a further training program among preschool staff

There are currently scarce research regarding further training programs and employees’ attitudes toward them. This present work examined 95 preschool employees from one municipal community in matters of emotional intelligence, need for cognition, and cognitive reflective ability and how these influenced their attitudes toward a further training program called International Child Development Programme, ICDP (study 1). Six participants were also interviewed in regards to more organizational aspects of the ICDP-training and their experiences of the program’s implementation in the actual worksituation (study 2). The results of study 1 showed a positive relationship between emotional intelligence and attitudes toward the program. Study 2 revealed lack of follow-ups and sustainability of the program in the real-life work-situation. Suggestions for countering these flaws as well as a more individually focused approach in embracing, applying and maintaining the teachings of a further training program are discussed.

Barns minnesåtergivning - uppkomsten av falska minnen och suggestionspåverkan utifrån positiv respektive negativ information

Falska minnen förklaras teoretiskt med bl.a. implicita associationer, och svårigheter att skilja mellan faktiska eller påstådda källor. I denna studie undersöktes huruvida positivt respektive negativt innehåll i en berättelse påverkar uppkomsten av falska minnen, enligt DRM-paradigmet. Deltagarna för studien (30 förskolebarn i åldrarna 3-6 år) delades in i två grupper där ena gruppen hörde en positiv version av berättelsen, och andra gruppen en negativ version. Deltagarna genomgick sedan tre minnestest med cirka en veckas mellanrum, där de svarade på allmänna frågor om berättelsen, genomgick igenkänningstest med bilder, samt svarade på två suggestiva frågor. Resultatet visade hög frekvens av falska minnen. Skillnader mellan gruppernas svar på de allmänna frågorna var statistiskt signifikant. Deltagarna som hört den negativa versionen tenderade att minnas mer korrekt på de allmänna frågorna, uppge färre falska minnen på igenkänningstesten och föll i lägre utsträckning för suggestionen. Resultaten diskuterades utifrån bl.a. Source Monitoring Framework och Fuzzy-trace teorin

Design and experimental studies of a biomass fired furnace for small- and medium scale heating applications

The main objective of the work was to develop a biomass fired furnace for small and medium scale heating systems, which has the ability to manage wet as well as unclassified biofuels with maintained low emissions of harmful substances. The system should also be able to cope with large and frequently occurring thermal output variations fulfilling rigorous environmental restrictions. The furnace consists of two combustion stages, a primary- and a secondary zone, and has a maximum thermal output of 500 kW. The studies have been focussed on the evaluation of the environmental performance of the new furnace. The main conclusion of the work is that the furnace fulfils all the pre-set requirements regarding operational- and environmental performance. The study has also shown that it is possible to use refuse in the form of horse manure mixed with wood-shavings and straw with satisfactorily environmental performance.Godkänd; 2004; 20061026 (haneit

Performance of a new wood-chips fired boiler for small district heating systems

A new bio fuel based boiler concept for small district heating systems has been developed. The boiler enables heat load variations from 100% down to 10% of nominal thermal output 500 kW fulfilling the most rigorous environmental restrictions. To obtain as low fuel costs as possible, an unrefined fuel in the form of wood-chips with moisture content in the range of 35-58% is used. The results are very satisfactory concerning both performance and emissions. Typical emissions of CO and NOx during the experiments are in the range 10 to 50 mg Nm-3 (5 to 25 mg MJ-1) and 130 to 175 mg Nm-3 (60 to 90 mg MJ-1), respectively.Godkänd; 2002; 20070224 (ysko

Integration of a hemicellulose extraction process into a biomass based heat and power plant

The development of processes where lignocellulosic biomass can be refined to several different end-products in the same plant, i.e. a biorefinery, will be important in the development towards a more sustainable society where fossil fuels are replaced. This paper presents the idea to integrate the production of green chemicals via hot water hemicellulose extraction of birch wood (hardwood) into a small-scale combined heat and power plant (CHP), in this case an externally fired gas turbine. A techno-economically successful concept could provide the option to turn a small- to medium scale CHP plant into a small- to medium scale biorefinery. The results show that the extracted wood-chips would serve very well as a fuel for combustion and gasification processes due to the relatively high heating value, low ash content and significantly lower concentrations of alkali metals. Under the assumed economic conditions, electricity can be produced to a cost in the range of €85.6 to €196.2 per MWhel and a fermentable feedstock stream with a xylose concentration of 65 g/L to a cost in between €0.44 to €4.15 per kg xylose depending on plant size and number of annual operational hours.Godkänd; 2009; Bibliografisk uppgift: CD; 20091109 (joakim

Serious games & Gamification : En studie av hur användare motiveras i en lärandeapplikation

AbstractE-learning applications are used both during school and at leisure and must be designed for both scenarios. Gamification and serious games, which is about implementing game design into other types of applications, are important concepts for this purpose. This qualitative study contributes knowledge in this area by evaluating a digital application that teaches driving theory. The purpose was to analyze the technologies driving motivation based on game mechanics, theoretical framework and analytical model. The study is based on qualitative interviews and the authors' own observations. The result indicates that users of the application are strongly motivated by the desire to pass the theory test, which means that the game mechanics that drives intrinsic motivations lose much of its significance. Therefore, the choice of playing techniques should be based on the purpose of the application and the balance between the extrinsic and intrinsic motivations to learn.Validerat; 20150621 (global_studentproject_submitter