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  • 1.
    Söderqvist, Helena
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Biokol för staden och jorden: Bränslehantering i en ny biokolsanläggning2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Biochar has the potential to reverse the trend of increasing levels of carbon dioxide in the atmosphere. Biochar has soil&improving properties through its porous structure and large active area which can be used by agriculture, hobby cultivation and urban green structure. In an innovative project, Stockholm has set up a pilot plant for biochar&production incorporated into an urban flow that combines waste management, energy production, soil improvement and climate change mitigation. The purpose of this survey is to evaluate the importance of biomass processing because the amount of energy and resources invested in pre&treatment affects the overall sustainability potential of the project. Two different processed fractions of biomass were empirically investigated in the plant during the first months of operation. None of the tested fractions worked satisfactorily in operation. One contained too many small particles which caused problems with tunnel formation and feeding. The other fraction contained too many large pieces which caused repeated shutdowns. The analysis showed disproportionately high ash content in the second fraction's biochar. That may indicate combustion, which should be investigated further. 

  • 2.
    Boström, Fanny
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Lundström, Johanna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Industrial Ecology.
    Biokols struktur och dess förmåga att adsorbera näringsämnen2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this project is to create a deeper understanding of biochar’s ability to adsorbnutrients. In the long run the aim is to find a way to use the most suitable structures of biocharfor a maximum adsorption of different kinds of nutrients. The objective of this project is tofind, through case studies and practical experiments, an effective method to examine andanalyze the structure of biochars and their ability to adsorb nitrates and phosphates.

    The conclusion of the project was that analysis of the biochar’s ability to adsorb is a complexmatter. The BET-analysis is a good method to find the structure of the biochar. However, iodinenumber analysis could be a better alternative to directly find a value on the biochar’s ability toadsorb. The ICP-analysis of the solutions only works for phosphor, therefore spectroscopywould be a better alternative since it also can detect nitrogen and the different compounds.

  • 3.
    Sundberg, Elisabet
    KTH, School of Chemical Science and Engineering (CHE).
    Granskning av avancerade pyrolysprocesser med lignocellulosa som råvara – tekniska lösningar och marknadsförutsättningar2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The population growth as well as a rapid technical and economic development globally affects the energy consumption. This requires a secure, stable and sustainable supply of energy. Today fossil fuels dominate globally and this results in environmental problems. Fossil fuels are also a finite, unsustainable resource. Thus, there is a need to replace fossil fuels with sustainable alternative sources of energy. This is also central for environmental goals both in Sweden and in the European Union. There are expectations that processes for the conversion of lignocellulosic biomass to solid, liquid and gaseous fuels can contribute to a transition from fossil to renewable fuels. In this thesis, carried out in collaboration between KTH and IVL Swedish Environmental Research Institute, one of the conversion processes is investigated in detail – pyrolysis. Pyrolysis is a thermal process that converts lignocellulose under anaerobic conditions at temperatures between about 300-650°C. Three phases can be obtained as products. A volatile which can be condensed into pyrolysis oil, a solid which may be termed biochar or charcoal depending on the end use, and a gas phase. The yield and the quality of the products is dependent upon the type of raw material, the type of reactor and the process conditions. An examination of the status of different pyrolysis processes on or on the way to the market has been made. The current degree of commercialization and what the future may look like for both the technology and the products have been assessed through literature studies, internet searches, and interviews with selected companies and individuals with expertise in pyrolysis.

     

    This report reveals that continuous pyrolysis is not yet a fully commercial process, but that it has the opportunity to reach commercialization during the right conditions. It is difficult to say when it occurs, due to various external factors, continued technical development, increased knowledge of the pyrolysis process and results of the current demonstrations. In this report, several critical factors for the commercialization of pyrolysis in Sweden have been identified, e.g. increased stability for policy instruments and that will limit the risk for investments (uncertainty and short-term decisions frightens investors) and the establishment of a value chain for the products, i.e. a stable market. Prices on fossil fuels and biomass feedstock are also important factors. Processes for the production of biochar is in the early stages of commercialization, and seem to have reached further in their development than processes for pyrolysis oil. The only fully commercial application of pyrolysis today is the production of charcoal that commonly is performed in traditional batch-wise processes. There are many possible uses for the products in which they have the potential to reduce carbon emissions and contribute to a more sustainable future. Standardization and certification of products is important, and demonstration of the use. Stabilization and further upgrading of pyrolysis oil is another important factor for commercialization. It seems like processes for catalytic upgrading are not yet sufficiently technically or financially developed to be able to provide a competitive product. Research and development in this area are ongoing. Integration of the process with incumbent industrial processes seems to be able to offer increased energy efficiency and reduced production costs.

  • 4.
    Jonsson, Erik
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Slow pyrolysis in Brista: AN EVALUATION OF HEAT AND BIOCHAR PRODUCTION IN SWEDEN2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This study is an analysis of the potential to have a slow pyrolysis power plant in Brista, Sweden. The study is investigating current technologies available and research and application of the pyrolysis products from the process. Pyrolysis has been known for over thousands of years. It has played an important part during the industrialization for producing coal in kilns. In recent years, the slow pyrolysis technology has started to become an area of interest because of the use and research surrounding the concept of biochar.Biochar is a term used to describe the char product of pyrolysis when biomass is used as a feedstock. The slow pyrolysis technology has a higher yield of char compared with other pyrolysis and carbonization methods. The biochar could be used as a soil enhancer to improve soil quality.Currently the biochar market is undeveloped and the concept is not well known in the general public. In Sweden there are no large scale slow pyrolysis processes for the production of biochar, in Europe there is some examples of slow pyrolysis power plant of various sizes. Slow pyrolysis has currently not been as profitable as traditional combustion of biomass. But it has the advantage to low grade feedstock sources and could become more profitable if the use and demand if biochar would increase.The profitability of establishing a slow pyrolysis plant is estimated by using the theoretical performance of such a plant. The slow pyrolysis processes used to create the model is based on the descriptions from the manufacturers Pyreg, Carbon Terra and BigChar. Data regarding the investment and operation cost of the plant is brought from manufacturers and other studies surrounding the slow pyrolysis concept. Different cost settings and fuel qualities for three different biomass types (Wood, forest residue and green garden waste) are applied to test the sensitivity of the process.The result of the study indicates the plants utilizing the green garden waste material will have the shortest payback period and return on investment. The green garden waste seem to be possible to use as a feedstock in a slow pyrolysis process to produce biochar of certifiable standard and large quantities are available in the area around Brista, but further research is needed.The larger reactor with a capacity of circa 3-5 MW had the highest return on investment and was not as sensitive to fluctuations of heat and biochar price as the smaller pyrolysis alternatives. The environmental benefit of establishing a slow pyrolysis power plant could not be determined. The char produced could work as a carbon sink if utilized as a soil enhancer. But the relatively small production capacity 0,5-5 MW makes the impact insignificant at a district level. But it could serve as a method to bring new research opportunities. New projects regarding biochar production in Sweden in under process and could bring new information that could improve the model of biochar production.

  • 5.
    Gustafsson, Ulrika
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Framgångsfaktorer för hållbar innovation: En fallstudie av Stockholms biokolsprojekt2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Innovation is often assigned an important role in mitigating climate impact and achieving sustainable development. Stockholm city has ambitious sustainability goals and aims to be carbon neutral by 2040. This will require an increased capacity when it comes to promoting and implementing innovative sustainability solutions. Climate friendly innovations need to move from environmental profile projects to the new “business as usual”.  The aim of this study is to contribute with knowledge about innovation processes within sustainable development and how they can be promoted.

     

    Strategic Niche Management (SNM) is a model which was developed to support a transition to sustainable development by promoting sustainability innovations. SNM suggests a number of hypotheses regarding important features of successful innovation niches, factors that will increase the potential of innovations to be developed, implemented and spread. Stockholm Biochar project is an innovative project which has received attention for its success and potential to contribute to sustainable development by reducing the city’s net carbon emissions. A case study of the Stockholm Biochar project has been conducted to identify how the project emerged and the main success factors for its development. The case study was complemented with an interview study with personnel from Vinnova, the Swedish innovation agency, focusing on their experience of success factors for innovation processes. SNM:s hypotheses has then been used to analyze the result of the case study, which was also compared to the result of the Vinnova-study. The analysis to a large extent confirms SNM:s hypotheses, regarding what factors contribute to a successful innovation niche, but also provide some specifications and elaborations on what these hypotheses mean in this specific case. This result is used to suggest possible complements to the SNM hypotheses that can be useful in contexts similar to the one studied. The result also points out important success factors that are not covered by the hypotheses suggested in SNM. Particularly the case study shows the important role of passionate enthusiasts as driving forces for innovation processes which is not pointed out in SNM hypotheses. The identified success factors, in combination with the complemented hypotheses, are used to formulate recommendations for how an organization can promote innovation processes within sustainable development.

    In short, the study shows that successful innovation processes require assigned resources, commitment and strategic work, e.g. visions with clearly stated sustainability goals, continuous evaluations on how innovations are contributing to these goals, active measures for gaining support for the innovation on multiple levels in society, and financial space for the development of innovations. The study also confirms the function of protected innovation niches and suggests that passionate enthusiasts have a significant role in innovations processes.

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