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Design of syngas cleaning by wet scrubber
Musilová, Petra ; Milčák, Pavel (referee) ; Baláš, Marek (advisor)
Gasification is a process which produces gas of low heating value, however, generated gas contains several pollutants. This thesis is dealing with the issue of purity and cleaning of generated gas. Theoretic part of thesis consists of research, describing the very process of gasification itself, mapping of possible pollutants appearing during gasification and particular ways of purifying gas, looking in detail at wet scrubbing with several scrubbing liquids. Further, it looks into proposition of conditions for wet scrubbing and balance of scrubbing liquids. Next part deals with calculation of purifying line. Main goal of calculations, is to determine the length of the pipeline, transfering polluted gas from the gasifier to the filter for elimination of solid particles and wet scrubber. Key aspect of length calculation was the input and output temperature of the gas, determined by characteristics of the filter. Calculation for wet scrubber istelf is also included, to detremine if the output temperature of the scrubbing liquid after the passage of the gas needs to be modified by additional cooling or heating. For experimental purposes, syngas generated by gasification of biomass, is gathered from the atmospheric gasifier Biofluid 2. Experiment itself inquires into the purity of the gas before and after the passage through solid particles filter and through the wet scrubber. The purpose of this thesis is to determine the chemical composition of gas before and after wet scrubbing, the difference of composition of tar gathered from purified and nonpurified gas and using gathered data to evaluate the effectiveness of wet scrubbing.
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Characterization of the chemical composition of the tar produced in the gasification of biomass
Mahelová, Zora ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Biomass is a renewable source of energy and represents an acceptable alternative to fosil fuels. Usable methods of energetic use of biomass are combustion and gasification. Main interest is focused on gasification in last years. Gasification is based on conversion of organic material to usable gaseous product called syngas, which can be used as a fuel for energy production. Large amount of tar is formed as a by-product of incineration and gasification of biomass. Tar is composed by various mixture of organic substances, has a negative effect on operating conditions and is a potential threat to environment. Experimental part of this study was focused on analysis of tar obtained by gasification of various kind of biomass. Selected groups of hydrocarbons and oxygen compounds were identified in analysed samples. Individual biomass samples were compared regarding to determined relative content of selected substances. Analysis was done by complete twodimensional gas chromatography with mass spectrometric detection (GCxGC/TOF-MS).
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Optimization of Gasification Process of Biodegradable Wastes
Elbl, Patrik ; Milčák, Pavel (referee) ; Lisý, Martin (advisor)
The aim of the diploma thesis is to discuss the gasification of biodegradable waste. The theoretical part deals with gasification with focus on gasification phases, types of gasification reactors and pollutants contained in the generated gas, especially tar. Further, there is listed the characteristic of alternative biomass fuels, namely digestate and sludge waste. The practical part is devoted to gasification on a fluidized bed reactor with the aim to test the possibilities of gasification of these fuels, to determine their specifications and the influence of various gasification media. In the final part there are discussed the results of the collected gases and tar.
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Hydrothermal Conversion of Biomass
Vařejka, Tomáš ; Elbl, Patrik (referee) ; Lachman, Jakub (advisor)
The main aim of this bachelor thesis is to search for hydrothermal technologies for biomass conversion to improved energy carriers. First part includes contains introduction to biomass conversion methods and its suitability for different types of feedstock. The following part is dedicated mainly to hydrothermal conversion processes, their history, development over time, used technology, process and product characteristics and comparison with conventional thermochemical methods. Finally, the current state of technology is evaluated, possible future developments are outlined and current problems which are preventing wider application of this technology are descried.
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Syngas Cleaning with Using Metal Catalysts
Baláš, Marek ; Noskievič, Pavel (referee) ; Kabát, Viktor (referee) ; Skála, Zdeněk (advisor)
Gasification of biomass is a one of the several technologies for energy production from biomass. Biomass is a promising renewable source of energy and is in a centre of attention of energy industry not only in the Czech Republic, but also in the EU and in the world. Gasification is a thermo chemical transformation of fuel with access of understoicheiometric amount of oxidizer which produces gas of low heating value. Its main combustible components are hydrogen, carbon dioxide and methane. Produced gas may be further used in power and heating plants. Besides combustible and neutral components, gas also contains pollutants such as sulphur compounds, chlorine compounds, ash and tar. It is tar which is considered to be the underbelly of gasification as it causes, along with ash, fouling in transport tracks and terminal equipment, and blocks direct application of gas. This dissertation thesis presents design of filter for elimination of tar from the gas generated in fluid gasification equipment. This work is closely related to current research at Energy Institute at Faculty of Mechanical Engineering at Brno University of Technology. First part deals with theoretical background of this issue. Biomass properties are mentioned in relation to gasification. Types of gasification equipment are described and principle of gasification including chemical reactions is given in detail. Special part is dedicated to pollutants in the gas, especially to production of tar and its properties, which is important for consequent work. Main focus is on possibilities of catalytic cleaning of gas from tar. Principle of tar decomposition is described and types and properties of catalysts are given. Part of the thesis tackles the issue of real operations and loss of efficiency of catalyst due to sulphur compounds, sintering and carbon fouling. Based on experience and analysis in the first part of the thesis, concept of elimination of tar from gas was laid out. In addition to that, method for measurement at Biofluid 100 experimental unit was outlined and filter for testing of industrial catalysts using metal was designed. Series of experiments were further conducted in order to find out efficiency of three opted catalysts for tar decomposition. Results of these experiments are described in detail and assessed in the conclusion of this thesis which also contains outline for economic assessment of method of gas cleaning using catalysts.
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Energy use of biomass
Musilová, Petra ; Brázdil, Marian (referee) ; Baláš, Marek (advisor)
The objective of this bachelor’s thesis is a research study of biomass use in energy industry with main focus on electric energy production. This thesis primarily concerns with biomass properties, biomass processing technologies and the application of such technologies in the Czech Republic. The first part of this work consists of biomass definition and its division. The next part deals with biomass energetic properties and following is a familiarization with cogeneration (the combined use of heat and power to create electricity). Furthermore this thesis analyses individual technologies used in electricity production. The last part focuses on heating plants, power stations and biogas plants, which use biomass and on charting these specific units in the Czech Republic.
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Syngas Cleaning in Hot Catalytic Filter
Lisý, Martin ; Skála, Zdeněk (advisor)
Disertation thesis deals with development of hot dolomite filter for the purposes of cleaning of gas polluted by biomass and waste gasification with ash and tar as well as sulphur and chlorine compounds as main pollutants. Gas is then cleaned so that it can be utilized in cogeneration units with combustion engines. This supports advancement of gasification techniques using decentralized power and heat generation especially for design of small scale units. Concrete aims of this thesis are stated in chapter 2. Experimental fluid gasification stend Biofluid 100 has been in operations at Brno University of Technology (BUT) since 2000 and it helps research of biomass and waste gasification. Development of the filter initially utilized needs and experience with the utility during cooperation of BUT and ATEKO Hradec Králové. Water scrubber was used for gas cleaning, however, this method proved to be ineffective. Alternative solutions were considered. Based on literature search, natural catalysts with limestone basis were opted. First part of the thesis presents literature search of this issue. Historic development and description of gasification process are briefly discussed as well as elementary classification of gasification generators. This part is followed by chapters dealing with gas pollutants. Tar – the most significant pollutant – is discussed in a separate chapter which presents tar formation, its classification, characteristics and methods for its removal. Brief summary of requirements on gas properties with respect to its utilization in various applications (especially in cogeneration units) follows. Other part of the literature search part focuses on methods of removal of tar from gas, especially on catalyst methods. Dolomite characteristics, description of dolomite calcination as well as simplified kinetic model of tar cracking using dolomite are presented. Based on literature search, laboratory and verification equipment was designed for the purposes of dolomite properties testing. Equipment description as well as description of experimental stend Biofluid 100 where the experimental tests were carried out can be found in introduction of the experimental part. This is followed by a complete description of pilot equipment design of hot dolomite filter with general description of experimental work process, brief characteristics of the fuel and catalytic material used. Final part of the work comprises of experiment results that were carried out on the pilot equipment. Focus is on efficiency of tar removal in connection with operation temperature, amount of catalytist and material used. Influence of these parameters on gas composition and energy intensity of the whole process under these conditions is mentioned as well. Possibility of autonomous unit operations without electricity heating is briefly outlined. Summary of the most significant results including the potential of future hot dolomite filter development is stated the final part of the thesis.
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Modelling of flow of two gases
Strouhal, Jiří ; Lisý, Martin (referee) ; Špiláček, Michal (advisor)
This bachelor‘s thesis deals with interaction of two gases of different temperature and chemical composition in gasification chamber ZKG. The first chapter of the thesis is focused on biomass as a renewable energy source. At first, there is definition of term biomass and then description of physical and chemical properties, by-product and basic types of biomass. There are also described the processes of pyrolysis and combustion. The second chapter is focused on different types of combustion and gasification devices. The third chapter of theoretical research briefly introduces basic methods of CFD modeling of processes in gasification chamber including turbulent flow, transport of chemical species and heat transfer. These methods are used for case mixing of combustion air and wood gas in combustion chamber ZKG. In conclusions are evaluated the results of simulation.
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Design for waste gas cleaning
Kubík, Michal ; Lisá, Hana (referee) ; Baláš, Marek (advisor)
This diploma thesis deals with impurities in waste gases and syngas. Those gases usually have low heating value and contain impurities which are the main issue of those gas fuels. Waste gases and syngas can replace natural gas after right gas treatment. First part is theoretical. It starts with description of biomass and gasification technology. Then the waste gases are described – their origin and usual composition. Next part is dedicated to impurities and is followed by impurities treatment technologies. For removing of almost every type of impurity wet scrubber can be used which is described in detail in following part. There are other types of gas cleaning technologies, so they are described too but not in such detail as wet scrubber. In second part the wet scrubber is designed, and its function is tested by cleaning syngas from fluidized-bed gasifier called Biofluid. During gas cleaning in wet scrubber the influence of water temperature on efficiency of tar removal is examined.
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Less usual technologies of biomass utilization
Červenáková, Jana ; Brázdil, Marian (referee) ; Baláš, Marek (advisor)
The main aim of the bachelor thesis is to elaborate less usual technologies of biomass utilization. In the first part of thesis are individual technologies described and divided. The second part of the bachelor thesis describes the concept of biomass and its specific featuress. The last part describes selected applications of less traditional technologies in the Czech Republic which produce electric power by using biomass fuel.
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