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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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Utilization of phospholipid fatty acids analysis for biodrying study
Stránská, Štěpánka ; Cajthaml, Tomáš (advisor) ; Innemanová, Petra (referee)
The aim of this thesis is the utilization of phospholipid fatty acids (PLFA) analysis to determine groups of microorganisms present during the biodrying of sewage sludge and their description in relation to the temperature regime of the biodrying. Four experimental cycles A, B, C, D were followed. Cycles A, B and C, D differred from each other in the sewage sludge collected from two waste water treatment plants. The cycles A, B, C and D were each performed in two reactors with different aeration regimes to compare the mesophilic (max. temperature ±50 řC) and thermophilic (max. temperature ±70 řC) regimes of biodrying. PLFA analysis was used to determine the microbial groups. Concentrations of individual PLFA were subjected to principal component analysis (PCA). The total PLFA concentration corresponding to total microbial biomass was decreasing during both temperature regimes of cycles B, C, D, while the total PLFA concentration increased towards the end of both temperature regimes of cycle A. The total PLFA concentration reached statistically higher values at the end of the mesophilic regime of cycles B, C and D. The development of fungi to bacteria ratio showed that fungi applied more with the progression of both temperature regimes of cycles A, B and the thermophilic regime of cycle C. Based on...
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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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Optimization of Gasification Process of Biodegradable Wastes
Elbl, Patrik ; Milčák, Pavel (referee) ; Lisý, Martin (advisor)
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.
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Hormones in sewage sludge
Jagošová, Klára ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Currently there is a spate of interest in the presence of pharmacologically active substances in the environment. These substances are excreted in active or metabolized form and with wastewater pass the wastewater treatment plant. Current treatment technologies do not always eliminate all pharmaceuticals effectively and therefore they enter the environment. One of these active groups is the group of steroid hormones. Steroid hormones belong to the group of endocrine disruptors and they are considered to be dangerous for the ecosystems. Due to the hydrophobic character of steroid hormones they undergo partial or total sorption from wastewater to sludge. Sewage sludge is the by product of wastewater treatment and contains heavy metals, organic contaminants and pathogenic bacteria. A part of produced sewage sludge is used as a fertilizer in the Czech Republic. This issue follows the regulation 347/2016 – conditions of agricultural use of sewage sludge. Waste policy of EU will alter the conditions of sludge disposal, so it is necessary to obtain data about the concentration levels, fate and behaviour of those pollutants. This thesis was focused on five natural female hormones and four synthetic, which are used as a part of contraceptive pills and substitutional hormonal therapy. Determination of hormones was performed in four steps including ultrasonic assisted extraction, clean up by solid phase extraction, derivatization and final analysis by gas chromatography with mass spectrometry on triple quadrupole in MS/MS mode.
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Hodnotenie fyzikálnych a chemických vlastností kalu z čistiarní odpadných vôd
Kaczor, Adrian
The aim of this project is to contribute to more effective usage of anaerobic fermenters in sewage sediment management by upgrading sewage treatment plants and thereby reduce the operating costs of these facilities. I build up on the first phase of this project, which I have already processed in my bachelor work. Within the II. stage, processes are considered in the anaerobic decomposition of sludge from wastewater treatment plants, where came to the modernization of the biological system. Part of this work was also the realization of laboratory measurements of the amount of biogas production from anaerobic fermentation of sewage sludge. The measurements were made with an external substrate added to the anaerobic reactor. At the same time, we also monitored the influence of these substances on a biogas production.
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The possibilities to combine biogas production and biowaste hydrothermal carbonization
Usťak, Sergej ; Honzík, Roman ; Muňoz, jakub
The objective of the methodology is to provide to farmers, agricultural consultants, owners and operators of biogas plants, to biowaste producers and processors, to experts in the field of soil reclamation and melioration, to investors and other interested parties on the concerned issues, the basic information about the potential at the combination of biogas production and biowaste hydrothermal carbonization. These options are evaluated on the basis of processing at accumulated energy intensity for the above combined processes and its comparison with conservative biogas production using the example biogas plant with installed electrical capacity of 800 kW. Part of the methodology is guided to evaluate the potential use of thermo- pressure hydrolysis unit as a device for digestate hydrothermal carbonization and other wastes in order to improve their performance, particularly in terms of employment in agriculture as highquality substrates for soil fertilization and for the purpose of soil carbon sequestration.
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