National Repository of Grey Literature 58 records found  beginprevious49 - 58  jump to record: Search took 0.01 seconds. 
Analysis of biochar aqueous extracts by separation methods
Tučková, Dominika ; Čáslavský, Josef (referee) ; Mravcová, Ludmila (advisor)
This master's thesis deals with the analysis of biochar extracts by separation methods. All analyzed biochar was produced from waterworks sludge by microwave pyrolysis. The aim of the thesis is the optimization of the sample preparation method and its analysis in a laboratory environment. With the ever-growing world population, the problem of a sustainable economy in both agriculture and waste management is becoming increasingly urgent. This fact has led most countries to consider promoting the so-called Circular Economy. The use of sewage sludge as a feedstock for biochar production is perfectly in line with this strategy. So far, however, the short term and the long term benefits and risks of using biochar have not been sufficiently described. Potentially hazardous organic substances were extracted from the biochar extracts by three techniques: liquid-liquid extraction, solid-phase extraction, and solid- phase micro-extraction. The obtained samples were analyzed using the GS-MS/TOF method. The individual methods were compared. Several biochar samples from WWTP Brno and WWTP Drahovice were selected and analyzed to verify the suitability of the selected sample analysis method.
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.
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.
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...
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.
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.
Fulltext: Download fulltextPDF
The possibilities to use hydrothermally treated biowaste for air and water cleaning
Usťak, Sergej ; Muňoz, Jakub ; Usťaková, Marie
The aim of the methodology is to provide to farmers, agricultural consultants, biogas plants owners and operators, originators and processors of biowaste, experts in the field of reclamation and recultivation, investors and other interested parties on issues concerned with the basic information on the use of hydrothermally treated biowaste, especially hydrothermally treated residues from anaerobic fermentation for water and air cleaning. In the introduction, the methodology provides a basic overview on literature regarding to coal similar materials, methods for their preparation, especially the way of hydrothermal carbonization, its basic characteristics and its possibilities and perspectives of application in practice. Furthermore, the methodology describes the actual results obtained during the research project usable in practice and provides their agrochemical, environmental and economic evaluation in the case of application at soils. At the end summarizes the main potential applications and uses of new products based on hydrothermally modified residues as essential components of the filter medium for water and air cleaning.
Fulltext: Download fulltextPDF
Analysis of the pyrolysis process of plant biomass
Jičínská, Karolína ; Ivanova, Tatiana (advisor) ; Kolaříková, Michel (referee)
Nowadays, there is an increasing consumption of fossil fuels however their combustion is associated with release of great amount of harmful substances into the atmosphere. Polluted environment and the rapid depletion of fossil fuels lead to increasing utilization of renewable energy sources. Biomass, one of these sources, can be transformed by thermochemical and biochemical processes into material/product with a higher energy value. The promising thermochemical process is pyrolysis. It is a process where the temperature heats material without access of media containing oxygen. This Bachelor Thesis entitled "Analysis of the pyrolysis process of plant biomass" was written as a literary review based on search and analysis of information for scientific articles from the well-known databases. The present Thesis summarized basics of pyrolysis as well as analyzed and compared various pyrolysis processes. The main processes are represented by slow and fast pyrolysis and also torrefaction. These processes are reviewed and evaluated, including technologies (reactors) that are nowadays applied. By pyrolysis process various kinds of carbon-based materials can be treated, however biomass is most commonly used for these purposes. Specific examples of scientific studies of plant biomass, which tested a potential use and output products, are also presented. The output of pyrolysis process consists of three products, namely liquid, solid and gaseous substances. The most desired output of pyrolysis is a liquid product, called as biooil, which has a wide range of utilization. In the last part of the Thesis advantages and disadvantages of the pyrolysis process and its energy and economic evaluation are presented.
Vplyv pridania zuhoľnatených rastlinných biomás na vermikompostovanie
Gundová, Zsuzsanna
Diploma thesis presents the issue of the impact of the addition of charred plant biomass for vermicomposting. The theoretical section describes the definition of biochar, its production, and application benefits to the soil, and other purposes. In other section, devoted to vermicomposting, there is defined the methodology of domestic vermicomposting. The chapter which is devoted to the own experiment is based on the hypothesis that biochar slows down the process of vermicomposting, reduces odor and emissions produced during the process, and that the combination biochar with vermicompost would be a suitable alternative fertilizer. During the experiment, two bins for vermicomposting were used. Biodegradable waste and biochar were added to the first one, and biodegradable waste were added to the second one. The same type and amount of substrate were added to the bins, and they were placed under certain conditions. The difference was only in the addition of biochar. During the whole process, vermicomposting diversity and the resulting product were studied. Vermicompost was evaluated by the available methods.
Identifikace negativních vlivů působících na přírodní památku Pahorek
Sklenka, Marek
Small natural sights in agricultural landscapes are threatened by a number of factors. To protect them you need to identify negative factors that influence them. Natural Monument Hill in the cadastral Bindings Vyškova is used as extensive pasture protected because of rare species of thermophilic plants. The area measurements were taken basal soil respiration, soil organic matter content in the soil by burning a number of moving forms of nitrogen in the soil. Contamination of the nitrogen from external sources has not been established, there have been differences in the content of organic matter in the soil, caused by the truth, like the management of the territory. Measurement of basal respiration showed dependency on the content of water in the soil during the vegetation period. The result of survey sites and outputs from laboratory measurements should be advised to head better care settings management of protected areas and improve its condition.

National Repository of Grey Literature : 58 records found   beginprevious49 - 58  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.