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Modelling of oxygen-enhanced combustion process
Naď, Martin ; Juřena, Tomáš (referee) ; Bělohradský, Petr (advisor)
The main purpose of the master´s thesis is the experimental study and the mathematical modelling of the combustion process in which the combustion air is enriched with the high-purity oxygen, i.e. the oxygen content is more than 21 %. This combustion technology is called as the oxygen-enhanced combustion (OEC). Since the experimental work required the manipulation with the pure oxygen, a part of the thesis is focused on risks and necessary safety associated therewith. The detailed description of the combustion chamber as well as of the components necessary for the operation of OEC is included. The main part of the thesis is the computational model of the combustion chamber and the simulation of OEC using CFD methods. The numerical results were then compared with the experimental data acquired during the combustion tests, namely the heat flux distribution along the combustion chamber and the distribution of in-flame temperatures in the horizontal symmetry plane of the chamber.
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Utilization of biomass for energy purposes
Malínský, Tomáš ; Bělohradský, Petr (referee) ; Recman, Milan (advisor)
The Master’s thesis deals with the renewable source of energy, namely with the biomass, and its utilisation in the Czech Republic. The thesis is divided in to two parts. The first part of thesis is theoretical. It summarises in form of literature search the general problems concerning the biomass, closely burning biomass. The second part focuses on practical utilisation of biomass and it´s burning in small scale boilers, designated for heating buildings. Boilers are detailed described. Attention is focused on machinery with automatic fuel supply. Four possibilities of improving them are described in last part of thesis. Automatic ignition, air supply, preheating of air and continuous regulation of process.
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Methods for suppressing NOx formation
Pořízek, Vít ; Hájek, Zdeněk (referee) ; Bělohradský, Petr (advisor)
The subject of this bachelor thesis are emissions of nitrogen oxides. The work deals with the suppressing their formation and with the possibilities of their elimination directly from the flue gas. The first part of the work analyses NOx emission limits for all stationary sources of pollution as well as the current effective legislation regarding emission limits of both European Union and the Czech Republic. Further part focused on nitrogen oxides themselves, their characteristics, impact on environment and last but not least on their formation mechanisms. Finally NOx reduction techniques are analysed and described, both primary and secondary.
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Utilisation of biomass in the Czech Republic
Malínský, Tomáš ; Recman, Milan (referee) ; Bělohradský, Petr (advisor)
The Bachelor’s thesis deals with the renewable source of energy, namely with the biomass, and its utilisation in the Czech Republic. The thesis is divided in to two parts. The first part of thesis is theoretical. It summarises in form of literature search the general problems concerning the biomass. The literature search discusses the kinds of renewable sources, the division of biomass on individual types and the technologies for biomass utilisation. The first part is closed by chapter about the legislation and financial outline of the problem. The second part focuses on practical utilisation of biomass in the company producing pet food. The second part discusses the thermal requirements of company, the boiler and it’s equipment, store of biomass and the fuel witch company uses.
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Burner testing
Rychter, Aleš ; Hájek, Zdeněk (referee) ; Bělohradský, Petr (advisor)
Bachelor thesis deals with testing of burners used in industrial applications. Overall is work divided into two main parts in which the first one is focused on basic classification of burners according to mixing type, fuel type and air supply system. The Second part of work is then focused on the burner tests. It describes types of tests and test environments in which the combustion tests can be carried out. In terms of tests, it is then necessary to make some important decisions, including the choices of testing fuel, combustion chamber and oxidizer, which have impact on the result. The preparation of tests also includes the developing of test procedure in which it is necessary to include the requirements of specific tests. The tests have to be carried out according to the relevant technical standards. After the realization of every test the evaluation of measured data has to be done and the test report summarizing the results of the test has to be issued. Since during the tests a number of process variables is measured like emissions, temperatures, pressures, flow rates, etc., the necessary instrumentation is described as well.
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Overview of information resources on biomass combustion
Komárek, Martin ; Bělohradský, Petr (referee) ; Hájek, Jiří (advisor)
The Bachalor's work is concerned to the mapping of the information resources in the area of biomass combustion. The main aim and theme on wich is the work mainly focused on, is to introduce basic, as well as related information sources, which from is possible obtain useful and valuable datas for any further manipultion together with research of biomass combustion and scene field of energetics, as the integral part. Significant attention in each chapter si aslo put on the gathering practice - oriented and applied informations.
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Characteristic parameters of combustion of low calorific fuels
Kvapil, Matěj ; Bělohradský, Petr (referee) ; Hudák, Igor (advisor)
The diploma thesis is focused on the combustion of the low calorific gaseous fuels. The first part is devoted to the characterization and usage of low calorific fuels. Then combustion theory focused mainly on emissions and thermodynamics. Next characterization of burners and their modifications for low calorific value fuels is described. Safe storage and handling of chosen gases is also included in the last chapter of the theoretical part. Practical part includes the description of the laboratory experiment, which was a part of this thesis. It consists of the experiment description, experimental plan, calculation and evaluation of emissions, high and low heating value, density, flame temperatures and heat flux. Laboratory experiment was carried out with different fuels. Low calorific fuels were simulated by gradual increase of the concentration of inert gasses in the natural gas. Increased concentration of inert gasses had positive effect on the emissions. Measurement of the flame temperatures confirmed that the decrease of emissions corresponds to the inert gas addition to the noble fuel. Heat flux and thermal efficiency of the combustion was almost identical for each configuration.
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Utilization of pyrolysis for liquid fuels production
Hruška, Daniel ; Bělohradský, Petr (referee) ; Hudák, Igor (advisor)
The main content of this bachelor thesis is description of matters of the pyrolysis units. Whereas there is an emphasize on basic description of the function, methods and the chemical processes during pyrolysis reaction in the pyrolysis unit for waste tratment a biomass, comparisons of the advantages and disadvantages selected types of the pyrolysis unit and analyzing of the product gaining during pyrolysis. Thesis also present qualitative comparison of the pyrolysis products and the commonly used fuels. The last part of the thesis is bestowed to a simplyficated mathematical and chemical calculation for energetic efficiency of pyrolysis products and comonly used fuels.
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Characteristic parameters of oxygen-enhanced combustion process
Dřímal, Jiří ; Hudák, Igor (referee) ; Bělohradský, Petr (advisor)
The thesis is focused on the experimental investigation of the oxygen enhanced combustion technology (OEC), which uses the combustion air with higher concentration of oxygen, i.e. more than 21 %. The OEC technology is used in those industrial applications, which requires higher thermal efficiency, increased productivity, improved character of the flame, reduced equipment cost, lower volume of exhaust gases and improved product quality. Although this technology involves a number of advantages, it is appropriate to mention some of its disadvantages such as refractory damage, inconsistent heating, increased pollutant emission or flame disturbance and/or flashback. The combustion tests of OEC were carried out at the burners testing facility that enables to test many types of burners (gaseous, liquid, or combined). The two-staged low-NOx burner fired by natural gas was used during the tests. The observed parameters include the effect of oxygen concentration in the combustion air on the NOx emissions, heat flux into the wall of the combustion chamber, in-flame temperature distribution in the horizontal symmetry plane of the combustion chamber and also the shape and dimensions of the flame. The combustion tests of the air-enrichment, air-oxy/fuel and O 2 lancing OEC methods were carried out at the burner thermal input of 750 kW and air excess of 1,1 for two combustion regimes, namely one-staged and two-staged fuel supply.
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