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Removal efficiency of selected drugs by various sorptive materials from water
Štofko, Jakub ; Mravcová, Ludmila (referee) ; Vávrová, Milada (advisor)
This thesis deals with sorption of selected drugs from model water by various sorption materials. Contamination of water resources by the pharmaceutical industry is a major problem today. Wastewater treatment plants, whose technological processes are unable to completely remove them, have a significant share in the penetration of these substances into the environment. At present, attention is paid to alternative materials that are capable of eliminating these substances. One of the potential sorption materials is biochar as one of the main pyrolysis products. This work focused on the assessment of the sorption properties of the different types of biochar and commercially used active charcoal. The sorption properties of the individual materials were compared with respect to the non-steroidal anti-inflammatory substance ibuprofen and the sulphonamide antibiotic sulfamethoxazole. The results of vial experiments were analysed on a liquid chromatograph with mass detection.
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Ecotoxicological assessment of biochar from sewage sludge
Kotzurová, Iveta ; Vávrová, Milada (referee) ; Zlámalová Gargošová, Helena (advisor)
The aim of this diploma thesis is to assess the ecotoxicological effect of biochar produced from sewage sludge. In case of application of biochar to agricultural land, both the soil and aquatic ecosystem may be affected therefore contact and aquatic tests were chosen to assess the ecotoxicological effects. Representatives of soil invertebrates were earthworms Eisenia fetida; Daphnia magna and Artemia salina were chosen from aquatic animals and terrestrial plants were represented by Lactuca sativa, Sinapis alba and Allium cepa. The results of contact tests point out how ecosystem could be negatively affected by biochar dose. Through aqueous extract were shown differences in sensitivity of individual organisms in aquatic tests. Dried sewage sludge was found to be the biggest burden for all tested organisms. The pelletized biochar with the addition of an additive showed the lowest negative effect on tested organisms.
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Determination of organic compounds in biochar produced by microwave torrefaction of biomass
Meindl, Jiří ; Vávrová, Milada (referee) ; Mravcová, Ludmila (advisor)
The thesis is focused on a determination of polycyclic aromatic hydrocarbons (PAHs) contained in dried pelletized sewage sludge and pelletized biochar. Biochars were made in mild conditions by microwave torrefaction of prepared sewage sludge. There were analyzed and quantified the 34 of standardized PAHs compounds in two series. The first serie, also called “Sada 1”, has been aimed at comparison of extraction methods for the chosen sample of sewage sludge and the sample of biochar. In serie “Sada 1”, there were compared efficiencies of chosen type of solvent or solvent mixture by comparison of yields for 34 standardized analytes in a sample of biochar and a sample of sewage sludge. There were compared also to total yields of PAHs and to number of quantified compounds in analyzed samples. The most reliable extraction method has been used for the next analyses of samples in the second serie called “Sada 2”. In Sada 2, there were compared different samples of the same type (e.g. biochar, sludge). The origin of sewage sludge (small or big sewage treatment plant expressed as PE) and used additives (cellulose, chaff, hay) as modificators for torrefaction process were variables for different type of sample. The results of analysis were identification of the most suitable sewage sludge and additive to be used as modificator for microwave torrefaction process. The main goal of correctly chosen sludge and additive was to minimize production of PAH’s during torrefaction and in samples of biochar.
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Using a modified biocharge to capture ammonia from the exhaust air
Kozlíková, Nikola ; Innemanová, Petra (advisor) ; Cajthaml, Tomáš (referee)
In my work I have dealt with the comparison of different types of biochar based solid materials, which could serve as a filling for ammonia capture filters. Three samples of biochar prepared from anaerobically stabilized sewage sludge were used to test the most suitable material at temperatures of 200 ř C, 400 ř C and 600 ř C, 3 samples of biochar prepared from oak wood at temperatures of 260 ř C, 400 ř C and 600 ř C, 2 samples of biochar prepared from a mixture of sewage sludge and wood chips pre-dried in a pilot scale biological drying plant, dried anaerobically stabilized sewage sludge and charcoal. The materials were impregnated with 50% sulfuric acid solution. They were then exposed to ammonia vapors for the time needed to complete the reaction on the surface of the impregnated material. Due to the chemical reaction, ammonium sulfate is produced, which can be used as a fertilizer in agriculture. It is known that the addition of biochar has a positive effect on the soil. In the case of a combination of biochar and ammonium sulphate, this may be an interesting soil additive. It could be an alternative to so-called scrubbers, where ammonia is trapped by bubbling dilute sulfuric acid. Transportation and application of the ammonium sulphate solution thus formed is not economically advantageous. To...
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Biochar Preparation in Quality of Activated Carbon via Pyrolysis of Hemp Waste
Šrámek, V. ; Staf, M. ; Pohořelý, Michael
The paper describes the preparation of adsorbents with the properties of activated carbon from biomass waste. Prime feedstock are hemp stems and a referential material is hardwood. The preparation is divided in two phases. The first phase includes pyrolysis in the temperature range 450-850 °C in the horizontal furnace and in the second phase the pyrolysed material is activated with steam and carbon dioxide in a vertical reactor. Finally, biochar was analyzed and relevant properties including BET surface and pore size distribution were determined to appoint suitable operational conditions for the biochar production in quality of activated carbon.\n
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22019040809400 - PDF
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Energetic use of wastewater sludge and microwave pyrolysis products
Šimek, Radim ; Ševčík, Jan (referee) ; Hlavínek, Petr (advisor)
The diploma thesis is focused on the energy utilization of sewage sludge before and after microwave pyrolysis process. The first part of the thesis deals with sludge management, treatment of sludge and its subsequent use or disposal. In the second part of the thesis prepared and modified samples of sludge from WWTP 1 and WWTP 2 are subjected to microwave pyrolysis process. Subsequently, samples are taken for analyzes to determine the total organic carbon, the specific surface area, the heavy metal content and the calorific values. The resulting data was processed in Microsoft Office Excel and presented at work. At the end of the thesis two case studies are then proposed for a specific design of the conceptual location of microwave pyrolysis for the sludge drying process and the drying process of the sewage sludge in the direct combustion boiler room.
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Ecotoxicological Assessment of Point Pollution in the Ecosystem
Doležalová, Šárka ; Beklová, Miroslava (referee) ; Kráčmar, Stanislav (referee) ; Koutný, Marek (referee) ; Vávrová, Milada (advisor)
The main subject of this dissertation is the ecotoxicological evaluation of significant point sources of pollution. These include wildfires and wide fires of factories and also industrial and urban wastewater treatment plants. The local application of pyrolytic product obtained from sewage sludge as the point source of pollution was also included in the thesis. Tests in aquatic and contact arrangement with using both water and soil organisms for ecotoxicity evaluation of selected matrices were chosen. Crustaceans Thamnocephalus platyurus, Daphnia magna Straus and sea bacteria Vibrio fischeri were selected as representative organisms of water animals. Duckweed Lemna minor was chosen as water plant. Further collembola Folsomia candida and earthworm Eisenia fetida were chosen as representatives of soil animals. Finally onion Allium cepa L. and mustard Sinapis alba are representatives of terrestrial plants. Submitted thesis deals about analytes of interest, their properties and ways of distribution to the environments. The output of the thesis is a comprehensive assessment of the effects of selected point sources of pollution on aquatic and terrestrial ecosystems organisms and ecotoxicological risks assessment. The fire extinguishing agents have been proven to be the most stressful substances for all selecteded organisms.
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Hydration of biochar prepared by using microwave pyrolysis of municipal sludge
Miklasová, Marta ; Komendová, Renata (referee) ; Kučerík, Jiří (advisor)
Microwave pyrolysis represents a possible solution of municipal sludge disposal. One of the final products of pyrolysis is amorphous porous carbon material called biochar, which can be used in agriculture as a soil amendment. As a rule, biochar is hydrophobic, but its addition can lead to an increase in water holding capacity. However, reasons of this improvement cannot be explained only by its high porosity. This thesis aims to contribute to the understanding the interactions between biochar and water under various environmental-relevant conditions such as direct water addition method and water adsorption from ambient air at different relative humidity. The thermo-analytical methods are common for investigation of the relationship between water and organic materials. One of these methods, differential scanning calorimetry, was used in this thesis. The first experiment was focused on measuring of melting enthalpy of freezable water in biochar pores. The results reflect the influence of pore size and properties of ice structure. The extrapolation of concentration dependence to zero enthalpy was used to determine non-freezing water (0,13–0,15 mg·mg-1 biochar), which reflects microporosity of the biochar. The second experiment was focused on the determination of evaporation enthalpy of water from biochar, which is a measure of the strength of water binding in biochar. This value indirectly reflects the mechanisms of the intake and release of water by biochar. Comparing the results for bound and pure water showed that in biochar is water bound weaker about 10–20 %. This led to conclusion that biochar binds water relatively weakly and the water exchange between biochar and soil is fast, despite the biochar hydrophobicity.
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