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Vliv některých organických hnojiv a minerálního hnojiva na vybrané půdní parametry =: Influence of some organic fertilizers and mineral fertilizer on selected soil parameters /
Šimečková, Jana
The search for new sources of electrical energy has influenced among others agricultural practice too. The fermentation process of biogas plants requires the adjustment of crop rotation to ensure sufficient input material throughout the year in the same composition, e.g. corn silage. The by-product, digestate, is applied to agricultural land as an organic fertilizer. However, the effect of its long-term application on soil properties is not explained. In a field trial in Vatín (soil type cambisol modal), the effect of application of digestate, mineral fertilizer and farmyard manure (150 kg.ha-1 N dose) on physical (bulk density, porosity and pore distribution, water holding capacity, minimal air capacity, structure and soil temperature) and hydrophysical (hydraulic conductivity, infiltration, moisture) soil properties was compared in the vegetation cover of corn monoculture, Norfolk crop rotation and permanent grassland. The three-year results indicate that the application of organic fertilizers (i.e. farmyard manure and digestate) has positively affected the physical condition of the soil, particularly soil structure and infiltration. Soil temperature amplitude was more balanced with digestate than with mineral fertilizer. The dynamics of the development of individual monitored soil properties were different concerning the type of vegetation cover.
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Digestate Grate Boiler
Krejčiřík, Jiří ; Milčák, Pavel (referee) ; Lisý, Martin (advisor)
This master thesis deals with the properties of digestate in combustion, design of construction solution of digestate boiler and experimental verification of boiler parameters. The first chapter deals with the properties of digestate as a fuel. It is followed by a chapter dealing with the existing measured results on a similar boiler. This is followed by a stoichiometric calculation of the digestate boiler. The next chapter is devoted to combustion chamber models. This chapter is followed by a chapter with experimental verification of chamber models and combustion process tuning. The last chapter contains design of construction and operational measures.
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Energy use of digestate
Kaška, Zdeněk ; Štelcl, Otakar (referee) ; Baláš, Marek (advisor)
This bachelor thesis deals with the research of biomass in general, its types and processing. Nowadays, biomass appears to be an environmentally and financially acceptable substitute for fossil fuels due to increasingly stringent emissions standards. The second part deals with its particular type, digestate. It is investigated whether the fossil fuel can be replaced or how the energy production process could be changed.
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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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Measurement of selected physical properties of the waste water from biogas plant
Ondruška, Vojtěch ; Zejda, Vojtěch (referee) ; Vondra, Marek (advisor)
The aim of this Bachelor’s thesis is the experimental measurement of physical and chemical properties of the wastewater from biogas plants. Thesis concisely describes wastewater and its origin. The main part is dedicated to the design of experiments and to the detailed description of the measurement of selected properties with the available laboratory methods. Measured data are evaluated and compared to literature. The results of this thesis can be employed to further develop the equipment for thickening wastewater from biogas plants or to other scientific activity in the field of waste management in agriculture.
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Foaming of fermentation residues during a vacuum evaporation
Knob, Jan ; Brummer, Vladimír (referee) ; Vondra, Marek (advisor)
The diploma thesis deals with the processing of digestate, which is the remaining material after biogas production. It aims to experimentally prove how chosen operational parameters of antifoaming agents influence digestate foaming associated with the vacuum evaporating technology. Based on the research of available antifoamers and the issue of digestate foaming itself, it was observed how three selected antifoamers (i.e. rapeseed oil, silicone antifoamer Erbslöh Schaum-ex and oleic acid), together with the decrease in the pH factor of the evaporating digestate, influence the final foam production. For the purposes of the research, an apparatus simulating the vacuum evaporating process was set up in which the heated sample was brought to boil by gradual pressure decrease. The process of foaming was observed in a transparent cylinder of a testing culumn. The essential part of the experimental activity is represented by a planned experiment which by means of a DoE (Design of experiments) method proved rapeseed oil to be very efficient. In contrast, other antifoamers, as well as the influence of the pH factor decrease, manifested themselves as insignificant factors, while the oleic acid even supported the foaming. The supplementary measurements led to a more detailed research of the effects of rapeseed oil and to the construction of a mathematical model describing how the concentration of rapeseed oil undermines the amount of generated foam. The main contribution of the thesis is firstly the evidence that rapeseed oil plays an important part in the reduction process of digestate foaming and secondly the determination of minimum substance concentration leading to the foaming reduction of a particular sample which is considered efficient enough to enable functioning of a vacuum evaporator. The thesis has also experimentally demonstrated the influence of some polymer organic flocculants which have been proved to support the foaming.
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Integration of a technology for digestate thickening in a biogas plant
Miklas, Václav ; Touš, Michal (referee) ; Vondra, Marek (advisor)
This diploma thesis is mainly focused on the digestate thickening in a biogas plant. First, overview of the biogas technology in the Czech Republic is presented. Furthermore, problems with waste heat utilization and processing of fermentation residues (digestate) are described in more detail. Based on the research, multi-stage flash (MSF) evaporation was chosen as the technology for the digestate thickening. The main part deals with the integration of the chosen technology into a biogas plant process. The programming language Python was used to simplify the given task. In the preliminary stage, a complex mathematical model of a biogas plant was created, focusing particularly on the mass and energy balances. Subsequently, a computational model of the MSF evaporator was programmed. A procedure for the integration was suggested using the sensitivity analyses. Additionally, the model of a biogas plant was extended with the MSF evaporator. The key outcome of the thesis is a technical-economic analysis in which the impact of digestate transport price and electricity feed-in tariff on payback period is investigated. The results suggest profitability of MSF evaporator for biogas plants without subsidized feed-in tariff. Contrastingly, installation of MSF evaporator in older biogas plants with subsidized feed-in tariff can be economically viable only in cases of significantly longer transport distances.
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Production of an alternative fuel from digestate using bio-drying method
Rákosník, Vítězslav ; Innemanová, Petra (advisor) ; Šváb, Marek (referee)
Biogas represents one of the renewable sources of energy, which has been growing on use rapidly over the past decades. Biogas is produced during anaerobic digestion of organic material in biogas plants and it is most frequently used for heat and electricity production purposes. There are still plenty of unresolved questions as it is with the other renewable sources of energy. One of the most actual topics is the question of the subsequent usage of a digestate - side product of the biogas production process. Digestate is generally applied as an organic fertilizer for farmlands, but there are tendencies to use its solid phase for another energy producing processes or eventually as farm animal bedding, which is unfortunately connected with few problematic aspects such as transportation and storing of the biologically unstable material with high amount of water in it. Answer to those challenges could be provided by the bio-drying of the digestate's solid phaze - substrate is dried up by heat produced during the microbial decomposition of organic matter and artificial aeration. The main objective of the experimental part of this thesis was to comprehensively test the process of bio-drying of unmodified solid phase of digestate from different biogas plants with agricultural origin for the purpose of...
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Bioplynové stanice v České republice
Válka, Tomáš
The thesis is focused on renewable energy, respectively biogas plants. In a literature part of this work there are described renewable resources used in the Czech Republic. There is also described the issue of biogas plants including their benefits for the region. The practical part is focused on one of the products of biogas plants, that is fermentation residue - digestate. In this part are presented the results of one year pot trial in which were observed the positive effects of digestate fertilizer on yield and quality parameters of selected species of vegetables - kohlrabi.
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Využití digestátu ve výživě kukuřice
Venc, Filip
In a one-year (2015) pilot plant field experiment with a maize, the effect of digestate and farmyard manure in combination with an urea on a yield of biomass and chemical composition of silage hybrid variety Ronaldino, has been compared. Variants of the experiment: 1) the maize fertilized by a destillate in the autumn and spring, 2) maize fertilized by a combination of the farmyard manure, applied in the autumn and the urea applied in the spring. The yields from the both variants were comparable. The second variant provided the yield 43,7 tonnes per hectare and the first variant 43,3 tonnes per hectare. Also a chemical composition of silages obtained from the both variants is com-parable. According to the obtained results, a fertilization with digestates is an adequate alternative to usual fertilisers in a technology of fertilization a silage maize.
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