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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Pásový dopravník přestavitelný / Adjustable belt conveyor

Drápalík, Martin January 2015 (has links)
The aim of this thesis is to design a conveyor belt readjustable to transport brown coal according to specific parameters. The introduction is focused on describing and dividing conveyor belts and characterizing their individual parts. The main part of the thesis is a description of selected components and design solutions, a functional computation carried out in accordance with the standard ČSN ISO 5048 and further an analysis of transported material's properties. The drafting documentation is attached to the thesis.
12

Návrh parního kotle na spalování hnědého uhlí, parametry páry 235 t/h, 14 MPa, 540°C / Stean boiler for sub bituminous coal, steam parametres 235 t/h, 14 MPa, 540°C

Horák, Stanislav January 2014 (has links)
The aim of the work is to design a brown coal combustion boiler of 235 t/h output. The work is divided into several parts. First, stechiometric calculations and calculations enthalpy of air and flue gas are performed. It is calculated heat balance of the boiler, the boiler losses and the thermal efficiency of the boiler is determined. After designing the combustion chamber thermal calculation is made. Then, individual heating surfaces are proposed and at the end of the calculations are controlling the overall energy balance of the boiler. For calculation was design documentation added.
13

Návrh opatření pro plnění emisních limitů u kotle bloku 210 MW / The proposal of measurements to fulfill emission limits for boiler of power unit 210 MW

Smokoň, Pavol January 2014 (has links)
This master‘s thesis deals with denitrification of brown coal-fired boiler of electric power plant. First chapters describe technical characteristics of the boiler and possible measurements which would lead to lowering NOx emissions. In order for boiler to meet emission standards valid from 1.1.2016 flue gas treatment by selective catalytic reduction is proposed. Main part of the thesis is thermal calculation of the boiler with modifications necessary in order to apply SCR. The aim of calculation is to determine flue gas exit temperature and temperature at catalyst area in order to assess the suitability of proposed modifications.
14

Roštový kotel na spalování uhlí a nebo dřevní biomasy o parametrech 200 t / h 9,3 MPa, 520°C / Steam boiler with grate firing , burning coal or wood biomas 200 t/ h, 9,3 MPa 520°C

Čech, Jaroslav January 2015 (has links)
The aim of the work is the design of a grate boiler of 200 t . h-1 output, which will burn brown coal or wood chips. The work is divided into several parts. First, stoichiometric calculation and the calculations enthalpy of flue gases and air are performed. After calculating the heat balance and loss of the boiler was counted boiler efficiency. The design of individual heating surfaces is proposed and at the end are controlled the overall heat balance of the boiler. The calculation is supplemented by drawings.
15

Roštový kotel na spalování uhlí a dřevní biomasy / Grate Boiler for Biomass and Coal Co-combustion

Baláži, Martin January 2016 (has links)
This thesis solves a design of a grate boiler burning wood chips or brown coal with a heat output of 160 MW. Stoichiometry flue gas is calculated according to the specified composition of each fuel. The dimensions of the individual heating surfaces are primarily calculated for burning wood chips and subsequently checked for the combustion of brown coal. Design of the boiler is completed by checking the overall heat output. Boiler design is accompanied by drawing documentation.
16

Kotel na spalování hnědého uhlí / Boiler for Brown Coal Combustion

Pavlo, Matej January 2016 (has links)
The aim of the master’s thesis is thermal calculation and dimensional design of boiler of 235 t/h which burns brown coal. The work is divided into several parts. In the first part, stoichiometric calculation and the calculations enthalpy of flue gases and air are performed. After calculating the heat balance and loss of the boiler, the boiler efficiency is counted. In the next part, thermal calculation of combustion chamber is calculated. Subsequently, design of the individual heating surfaces is proposed. Finally, the overall heat balance of the boiler is inspected. The calculation is supplemented by drawing of the boiler.
17

Pásový dopravník přestavitelný / Adjustable belt conveyor

Drápalík, Martin January 2016 (has links)
The aim of this thesis is to design a conveyor belt readjustable to transport brown coal according to specific parameters. The introduction is focused on describing and dividing conveyor belts and characterizing their individual parts. The main part of the thesis is a description of selected components and design solutions, a functional computation carried out in accordance with the standard ČSN ISO 5048 and further an analysis of transported material's properties. The drafting documentation is attached to the thesis.
18

Proměny oblasti v okolí Krušnohorské železnice v době industrializace / Changes of the area around the Ore Mountain Railway during the period of industrialization

Monhartová, Monika January 2016 (has links)
This diploma thesis discusses the changes of the cultural landscape and its inhabitants around the Ore Mountain Railway during the period of industrialization. The goal of a thesis is to describe the changes during the period of industrialization and the influence of newly build Ore Mountain Railway. The Ore Mountain Railway was a significant international transport link furthermore existence of railway had direct influence on the development of small villages in the vicinity. This thesis focuses on villages directly influenced by this railway in the period of industrialization. The first part is devoted to explanation of fundamental terms and description of region. Furthermore, there is a historical description of the region before the period of industrialization. In the next part is stated specific major development of the cultural landscape related to the growth of traffic and industry. In addition, there also describe social changes in the period of industrialization. The major focus of thesis is on the village Hrob. This village is used as an example for explanation of the influence of the Ore Mountain Railway to its region. In the last part is briefly described current state of the Ore Mountain Railway in these days.
19

Porovnání diverzity spontánně zarostlých a technicky rekultivovaných výsypek na Mostecku / The comparison of diversity on spontaneously re-vegetated and technically reclamed dumps from coal mining in the Most region

MÁLKOVÁ, Lucie January 2011 (has links)
Sites left to spontaneous vegetation succession and those technically reclamed were studied and compared on dumps in the Most Region, NW Czech Republic. Data were sampled in summer 2008 and 2010. Species composition and species diversity were analyzed using phytosociological reléves arranged along 100m transects. Alfa- and beta-diversity were evaluated. There were significant differences between sites in alfadiversity. Beta-diversity was highest in the spontaneously re-vegetated sites. There were also differences in species composition among the studied sites. I consider using spontaneous succession as appropriate in restoration of land disturbed by brown coal mining. It is a good alternative to expensive technical reclamation.
20

Brown coal char CO2-gasification kinetics with respect to the char structure

Komarova, Evgeniia 11 September 2017 (has links) (PDF)
This research has been performed in the framework of the Virtuhcon project, which intends to virtualize high temperature conversion processes. Coal gasification is one of these processes, which is nowadays considered as a promising technology for the chemical industry. This study is devoted to the coal char physical structure, which is one of the most important parameters influencing coal gasification reaction. First, this study presents the extensive literature review of the char physical structure role during its conversion. Collection of the char structural properties as well as their changes during char conversion are shown and discussed. Literature review is followed by the experimental investigations. Chars prepared from two brown coals (Lusatian and Rhenish) were gasified in a laboratory scale fluidized bed reactor in CO2 at temperatures of 800, 850, 900, and 950 °C and atmospheric pressure. Char samples were gasified completely as well as partially in order to evaluate the reaction kinetics and char structural changes during the reaction, respectively. Complete gasification curves were evaluated by different methods, including application of three gasification models (the Random Pore Model, the Volume Reaction Model, and the Shrinking Reaction Model), instantaneous reaction rate approach as well as the self-developed surface-related reaction rate approach. The results of different approaches were compared. This study also presents a comprehensive methodology to analyze coal char physical structure. The variety of measurement techniques (gas physical adsorption, mercury porosimetry, helium pycnometry, SEM, etc.) were applied to assess structural properties of the char, such as specific surface area, particle density, porosity, pore size and shape, structure morphology, etc. Problems associated with the choice of a proper measurement technique and the comparability of the data delivered by different techniques were discussed. The main objective of the study was to link char structural changes to the char gasification kinetics. The specific task of this thesis was to investigate pore size in relation to their availability for the reaction. As such, specific surface areas of pores of different sizes (from sub-micro to mesopores) were correlated to the instantaneous reaction rates. Both chars exhibit similar trends in their structural changes during gasification, although the absolute values differ, especially with respect to the pores of microscale. Furthermore, structural changes were caused not only by the reaction but also by the influence of the heat treatment, especially at the earlier stages of the reaction. The most reasonable correlation has been achieved between the instantaneous reaction rate and the specific surface area of mesopores. Sub-micro- and micropores did not govern the gasification reaction under given conditions. Finally, kinetic parameters derived from different evaluation methods were reapplied in order to test their ability to predict the experimental data. Each of the method has its advantages and disadvantages as used for the kinetic evaluation. The results of this study represent a substantive base of the experimentally derived data concerning physical structure and morphology of coal char. The findings can be used in numerical and simulation studies for development, validation, and improvement of the models which consider coal particle as a reactive porous solid.

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