čas: 7.6.2020 11:34:55
Obnovit | RAW
Department of Gaseous and Solid Fuels and Air protection
List of available PhD theses
Ambinet air quality in highway tunnel
Degradation of materials in gas environment at high temperature.
The nuclear generation IV reactors are considered to replace older energy producing devices in the future. Several types of generation IV reactors are proposed. In two types of them - High Temperature reactor (HTR) and Gas Cooled Fast Reactor (GFR) helium as a coolant is used. Pressure and temperature of helium in these types of reactors reached very high values - to 16 MPa and 1000°C, and higher temperatures are planned for the future to achieve higher effectivity for conversion of thermal to electrical energy. This environment may damage components of the system, therefore structural materials have to be as resistant as possible. Structural materials for HTR a GFR may be distinguished into two types: metallic and nonmetallic. Among metallic materials for HTR belong mainly high temperature resistant steels and metal alloys. On metallic materials the tests of high temperature creep (constant strain) and fatigue (dynamic strain) resistance, corrosion in impure helium, etc. should be performed. Nonmetallic materials used in HTR are mainly nuclear graphite and composite materials. These materials should be tested for oxidation in impure helium, creep, dimensional and structural changes at high temperatures under and without radiation, etc.
Determination of the composition of natural gas using Raman spectroscopy
Natural gas contains hydrocarbon and inert components which can be commonly determined using gas chromatography. Utilization Ramana spectroscopy for analysis of substances contained in the natural gas has not been more widely studied and the use of spectral methods has great potential in the future compared with chromatographic methods. The aim of this work is the study of qualitative and quantitative analysis of the components of natural gas using Raman spectroscopy.
Heavy metals removal from flue gas produced during combustion of coal
The work is focused on testing of adsorbents suitable to the mercury removal from the flue gases produced by the brown coal combustion. The goal is to find the optimal adsorbents to allow effective removal of mercury from power plant flue gases produced by combustion of the Czech Brown, to estimate their adsorption capacities for mercury under the conditions of power plant flue gas adsorption (high temperature and high humidity) and the possibility of the eventual regeneration of saturated adsorbents. The work is part of the grant project TACR.
Influence of hydrogen in natural gas on the gas infrastructure
The thesis is focused on the study of different hydrogen content in natural gas and its influence on the gas infrastructure. At present, hydrogen is intended to be added to natural gas either as a pure gas or for example as a part of the gas produced by the catalytic hydrogenation of carbon dioxide. The issue of adding hydrogen to natural gas involves, in particular, mixing of hydrogen with natural gas in the pipeline system, influence on the calorific value and combustion properties, influence on the measuring and analytical systems, sealing systems, influence on natural gas compression at compressor stations, reduction of transport capacity, reduction of methane number or limiting factors during the storage of hydrogen - natural gas mixtures.
Leaks flanged connections for various gaseous media
The thesis is primarily focused on the study of gas leakages through flange connections for helium systems in the concept of the IV. generation nuclear reactors. Nevertheless, part of the work will focus also on testing leakages of other gaseous media, especially natural gas or hydrogen. Except gas leakage testing over different sealing materials, penetration tests of permanent gases into the piping system under increased pressure and elevated temperatures will be executed.
Use of the dry reforming in the production of synthesis gas
In recent years, the use of carbon dioxide in the technology known as CCU (Carbon Capture and Storage) is still topical issue. One of these technologies is the use of carbon dioxide in the reforming of natural gas (methane) in the production of synthesis gas, which is a common raw material in oil refineries. Use of carbon dioxide during this process would permit its use and extend its carbon footprint. The aim of this work will be to determine suitable process conditions (temperature, pressure), catalysts and kinetic conditions. The process energy balance will also be compiled for possible industrial use.