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Toxicity of fine and ultrafine particles from combustion processes
Berková, Helena ; Köbölová, Klaudie (referee) ; Adamec, Vladimír (advisor)
The bachelor thesis deals with the toxicity of fine and ultrafine particles from biomass combustion. The theoretical part is focused on the current state of this issue from the origin, physicochemical properties, mechanism of toxicity of particles, to their impact on the environment and human health. The following is an overview of tests for determining the toxicity of fine and ultrafine particles. The experimental part is devoted to the actual sampling of biomass combustion, their characterization, cultivation of the tested organism and toxicity tests. The results of acute toxicity tests are expressed in terms of percentage mortality values and then the toxicity is evaluated.
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Emissions from biomass combustion
Vaněk, Michal ; Lisá, Hana (referee) ; Baláš, Marek (advisor)
The thesis deals with harmful substances originating as products of biomass combus-tion and possibilities of reducing their emissions from boilers for household heating. First of all, biomass is introduced and a description of important fuel properties in terms of its combustion is given. Secondly, the characteristic of the combustion process and origination mechanisms of individual substances are presented. This is followed by a description of the properties of these substances and their impacts on human health and the environment. The purpose of the next chapter is to present the reader with current legislation addressing the emissions of small boilers. Then a separate chapter describes possible methods that can be used to reduce emissions of these devices. Finally, several measures in the form of modifications and devices, capable of reducing harmful emissions of small boilers are given.
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Temperature field in solid fuel
Ptáček, Pavel ; Šnajdárek, Ladislav (referee) ; Pospíšil, Jiří (advisor)
The diploma thesis deals with a temperature field in a solid fuel during the combustion process. At the beginning of this thesis, research of available literature was conducted to obtain information about the composition of wood, properties affecting the combustion process, and the basics of heat transfer. Afterward, the temperature profiles of the samples were recorded during the measurement in the observation furnace. The temperature profiles of samples of six different sizes which were made of spruce and beech wood were subsequently evaluated and compared. Based on experimentally obtained data, a mathematical model was created in the OpenModellica software. Finally, the results of the mathematical model were compared with experimentally obtained data and appropriate conclusions were deduced.
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Mathematical Model of Biomass Boiler for Control Purposes
Máša, Vítězslav ; Klemeš,, Jiří (referee) ; Olehla, Miroslav (referee) ; Švarc, Ivan (advisor)
he thesis focuses on building of dynamic mathematical model of biomass boiler as a controlled system and the use of this model in practise. At the first part of the thesis the area of energy production using biomass is introduced and the current development at the area of the automatic control of biomass boilers with medium energy output (in units of MW) is described. Although the main topic of the thesis is the construction of model of biomass boiler for control purposes, thesis deals with technology of boilers and principles of its inner processes as well. Creation of the model comes out not only from these important findings, but also from experimental data collected during measurements in real operation. Heat and mass balance calculations were made according to these data and they serve to precise static properties of experimental unit for biomass combustion. Central part of the thesis presents development of the final model that resulted from balance calculations and from step responses of the system obtained by measuring. Built dynamic model is compared with experimental data through simulations in Simulink and verified. At the next part the model of controlled system is completed with control system and closed-loop control circuit is validated and verified by simulation. Then the design of new controller configuration, which improves the quality of control considerably, is presented. At the final part of the thesis, possibilities of other use of the model of boiler are given, both in control theory and in industrial practice.
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Change of heat source in a heating palnt 2.5 MW
Pikola, Jan ; Pospíšil, Jiří (advisor)
The scope of this Master´s thesis is estimation of changing of heat source in a heating plant 2.5 MW. In the present heating plant burns natural gas, placing of the heating plant makes it possible development source of burning biomass. The scope of thesis is establish with regard to developed capital and operational costs, next effects to environment in scene of heat source, measuring and regulation of technological unit, determination of acceptable size of fuel depot and composition of fuel and ashes economy. The results of this Master´s thesis can be used as a basis about determination toward investment.
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Energy balance of biomass heating plant
Žmolík, Václav ; Šen, Hugo (referee) ; Baláš, Marek (advisor)
This thesis deals with a design of a biomass heating plant combinating a Rankin-Clausius cyklus and a CHP unit. The CHP unit fuel is a biogas and the boiler fuel is a wooden chip. The adapted CHP unit regenerates feed-water of the R-C cycles. This design is technicaly and economicalty compared with the Rankin-Clausius cycle without feed-water regeneration by the CHP unit.
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Performance of the system for energy utilization from biomass
Koláček, Richard ; Máša, Vítězslav (referee) ; Pavlas, Martin (advisor)
This diploma thesis deals with the problems associated with acquisition of experimental data from technological unit for biomass combustion with nominal capacity of 1 MW, with regard to determination of thermal efficiency. In the introduction part, parameters of currently available biomass-based fuels as well as of those with large potential in the future are summarized. Further, a review in the field of biomass combustion technology is given. Biomass boilers are compared according to their technical parameters, function and benefits and drawbacks. In theoretical part methods for determination of thermal efficiency by direct method, indirect method and modified indirect method are described. Main parameters influencing resultant values of efficiency are included into the analysis. In final part an evaluation of real operational data from prototype unit combusting wooden chips is made. Recommendations for further experimental data gathering and their processing with the aim to evaluate thermal efficiency are suggested.
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Process identification, experimental unit for biomass combustion
Macalík, Radek ; Němec, Zdeněk (referee) ; Máša, Vítězslav (advisor)
This thesis dissertates the identification of existing experimental unit of biomass combustion. It analyses particular methods of identification, the selection of a model and methods of the estimation of parameters, especially by using last square method and analysis of time-response characteristic. It describes common identification procedure and particular algorithms which were used in practice for obtaining model’s parameters. The thesis also mentions popular software tools used for the modeling and the identification of systems. It comprises the implementation of obtained mathematic models using programming environment Borland Delphi as well.
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Using Biomass for Cogeneration of Heat and Electricity
Vašíček, Martin ; Macháček, Jan (referee) ; Toman, Petr (advisor)
Theoretical part is concerned to disposal of biomass kinds and various forms of applications. The basic characteristic for each kind of biomass and their forms are presented. Characteristics of energy plants and woods are more detailed. In work are described two fundamental kinds of combustion, fluid combustion and grate combustion, which are used in power plants and heating plants. The work describes process of gasification and obtaining wood gas from biomass. Evaluation of (energy plants, wood biomass and the rest from agriculture production – straw) in light of heating power, treatment, handling, ash creation and environment pollution is provided. Work is concerned to redemption price history, volume of produced biomass and perspective to future. Czech Republic legislation gives support to biomass usage by guarantee for electric energy purchasing and same redemption price perspective. Explain term of cogeneration, possibility of cegeneration units application – their kinds with fuel usage aspect (biogas, natural gas, wood gas). Practical part is concerned to design of such kind of unit. Cogeneration unit will be installed in company, which producing wood. For this reason will be used wood biomass to produce wood gas. Size of unit, fuel consumption, and cost saving in comparison to electric energy together with recovery of investment are calculated. In work is drawn out possibility to connect this unit to distribution electrical network, possibility of electric energy distribution and due this to improve backflow. Noticeable are possibilities to get state grant from various grant sources.
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