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.

This diploma thesis deals with the problem of so-called two-stage gasification, which have the potential of producing gas-fuel with a very low tar value, which has a parameter of its quality evaluation is very important. The thesis deals with processes that are taking part in pyrolysis and gasification, further attention is focused on finding parameters and optimal conditions of operation in order to suggest the basic design of gasification unit. The actual design of the unit consists of a simplified energy and mass balance model and the design of its own partial and significant components. The work is supplemented by an experiment and its evaluation.

The aim of this diploma thesis is to describe the gasification of biomass with a mixture of oxygen and water vapor. The theoretical part is focused on the gasification process, gasification reactors and the quality of the resulting gas. In the experimental part we look for the ideal ratio of oxygen to water vapor, which are used as gasification media. Subsequent measurements are carried out on the fluidized bed reactor, the results of which are further processed and evaluated.

The diploma thesis deals with the issue of pollution of the generated gas after the gasification process and its subsequent cleaning using a barrier filter. The theoretical part of thesis consists of research on the gasification process, the effects on the gasification process, pollutants in the gas and gas cleaning with a focus on the purification of gas from tar. The experimental part of this thesis is devoted to the gasification itself in a fluidized bed gasification reactor in order to test the effect of the catalyst, which was calcined dolomite, the composition of the gas at variable parameters of water vapor and the temperature inside the laboratory filter.

This diploma thesis deals with the issue of pollution of the generated gas during gasification. It consists of two parts. The first part is theoretical, where there is a search describing the course of gasification. There is also an overview of impurities in the generated gas and a description of methods suitable for gas purification. The second part of the work is focused experimentally, where various fillings of the barrier filter are tested during gas cleaning.

This Master Thesis is about the Gasification of hammer-milled chipboard. The opening part is about general theory of bio-mass gasification and the gasification machines. Next there is a chapter about the products which are included in the gas after gasification and the methods, how to remove them from the gas. This thesis is about gasification legislative acts and novels too. The main body of the thesis is about the experimental gasification in Biofluid 100 machine. This machine is located in the Fakulty of Mechanical Engineering in Brno. There were the samples of gases and tars collected during the gasification. From this samples was made the analysis. Then the mass content BTEX, n-alkans and PAHs.According the process of experiments was set the procedure of gasification. Finally there was a evaluation of the chipboard gasification made.

This thesis evaluates the possibility to use a iron-based catalyst as a pyrolysis vapour conversion catalyst. The iron catalyst was also compared with the mineral dolomite. The experiments were facilitated at Cortus Energy's demonstration plant in Koping, Sweden, by in situ instal- lation of the experimental setup to an outlet of the pyrolyser unit. The pyrolysis vapour from Cortus Energy was converted for a total of 8 hours by passing it through a packed bed reactor containing the iron-based catalyst while sampling gas and oil from the feed for analysis. The outset for the operation on the dolomite catalyst bed was the same as for the iron catalyst with a resulting collapse of the bed when the pyrolysis vapour was introduced. The permanent gases were analysed on site with a µ-GC unit while oil samples were condensed and analysed with GC-MS, H-NMR and Karl Ficher titration. The carbon laydown and surface area of the catalyst was determined as well as the phase changes of the catalyst surface with XRD. The results showed clear indications of bio-crude conversion with an eightfold increase of the H2 concentration of the synthetic gas from 3.38 % to 26.69 % on a dry gas basis. The oxygen to carbon (O:C) ratio decreased in the treated pyrolysis oil compared to the untreated oil while the hydrogen to carbon (H:C) ratio showed indications of dehydration of the oil. The gas and water content of the stream increased while 57.2 % of the oil was converted in the process. Lastly, the iron-based catalyst did not seem to favour the conversion of alkylated phenols.

<p> Coal tar is a rich source of polycyclic aromatic compounds (PAC) which include hydrocarbons (PAH), sulfur-containing aromatics (PASH), nitrogen-containing aromatics and high molecular mass PAH. The separation of coal tar into four fractions was carried out on activated (170°C, 48 hrs) neutral alumina. Low mass aromatics and aliphatics were eluted with hexane in fraction A1 (2.2% recovery), while PAH/PASH were eluted by benzene in fraction A2 (25%). High molecular mass PAH were eluted by dichloromethane in fraction A3 (5.5%) and nitrogen-containing aromatics were eluted by methanol in fraction A4 (21%). These fractions were characterized by normal phase liquid chromatography, GCMS, probe mass spectrometry (for fractions A3 and A4) and LC-MS (for fraction A3).</p> <p> While ratio of PASH to PAH in fraction A2 was rather unfavorable (25:1), the separation of PASH from PAH was attempted using two methods: an oxidation/reduction method and a ligand exchange method. The oxidation/reduction method of Lee was a complete failure. The PdCl2-silica method of Nishioka was partially successful. Of the 25 thia-arenes identified in fraction A2, 12 eluted with the PAH while the other 13 were either partially (5) or fully (8) retained by the PdCl2-silica gel column and then eluted later to give a sulfur-enriched fraction. This fraction was further separated using normal phase HPLC to afford sulfur-containing compounds with molecular masses between 184 amu and 258 amu which exhibited almost no contamination due to PAH. Thus, it would be possible to purify about one-half of the PASH from a complex mixture such as coal tar.</p> <p> Fraction A3 which contained high mass PAH was subjected to semi-preparative normal phase HPLC to afford several high molecular mass PAH fractions. The 326 amu PAH fraction was selected because it contributed to 10% of the genotoxic of the mixture. This fraction was further separated by normal phase HPLC and the subfractions were analyzed by reversed-phase HPLC with diode-array detection. Thirty-five peaks were collected from the reversed-phase HPLC analysis and were characterized by probe mass spectrometry and fluorescence spectroscopy (in part). Of the 35 peaks, 8 peaks were eluted in the mutagenic active range; these eight compounds will be evaluated using the Ames assay to determine which are active mutagens.</p> / Thesis / Master of Science (MSc)

No description available.

No description available.