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Control methods for wastewater pH
Picka, Marek ; Vondra, Marek (referee) ; Miklas, Václav (advisor)
The bachelor thesis initially deals with the process of wastewater treatment with a focus on measurement, pH control and related issues. The pH value is an important parameter in wastewater treatment, which influences physical, chemical and biological processes as well as digestate treatment processes. This paper focuses on the process of thickening of digestate from a biogas plant by evaporation, which is normally associated with the leakage of volatile ammonia into the distillate. In order to eliminate this phenomenon, four methods of pH reduction were compared, which leads to the conversion of nitrogen from the volatile undesirable form 3 to the desirable form + 4 or 3 , which does not evaporate into the distillate during the evaporation process but remains in the concentrate, thus yielding a high quality fertilizer. Of the 4 methods discussed, the nitrification method appears to be the best in terms of the quality of the fertilizer output, but its disadvantage is the long retention time. From the point of view of flue gas utilization, lowering the pH by bubbling 2 and acidification with acid is a suitable method. For cases where speed and low acquisition costs are important, pH reduction with acid is preferable, unless high operating costs are a problem. In order to assess the correct method of pH reduction for a particular biogas plant, a techno-economic evaluation and consideration of other operational constraints is required and will be the subject of future work.
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Mass transfer during desorption
Lindovský, Jiří ; Svěrák, Tomáš (referee) ; Kalivoda, Josef (advisor)
This master thesis deals with development and optimalization of apparatus for ammonia desorption from liquid organic wastes, generated by biogas plant. There is a high ammonia concentration in biogas plant waste products. That limits its application as a fertilizer in an agriculture. The main aim of this theses is finding optimal conditions to reach required efficacy of removing ammonia nitrogen from a liquid digestate. For this purpose, two pilot plant devices were used, and optimal conditions for ammonia desorption with its subsequent absorption by acid solution were investigated. One of the tested devices is a membrane contactor with polymeric hollow fibers. The second is a stripping device, which was used for measuring the pilot scale experiments. At the time of writing of this thesis, the device is subjected to a process of optimalization. The transferred ammonia nitrogen absorbed in acid solution was analyzed by UV-VIS spectrometry. The suitability of both devices for the required ammonia desorption efficiency has been demonstrated. Furthermore, the kinetic curve of the experiment was investigated under different conditions. The optimalization of devices will take place according to the results obtained in the experimental part of this thesis. The optimized devices will be placed in biogas plant full operation.
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Assessment of evaporator integration into biogas plant
Peťovský, Patrik ; Touš, Michal (referee) ; Máša, Vítězslav (advisor)
The main waste output of the biogas plant is digested which is used as fertilizer. It can be further process. Digestate cannot be discharged freely into surface waters. This problem is associated with high transportation costs and higher costs of storage tanks in the new biogas plant. The aim of this bachelor thesis is to assess a suitable evaporation system for a particular biogas plant. The evaporation system leads to the concentration of digestate by evaporation water. The system uses heat produced by cogeneration unit. The main consequence of the integration is lower cost for the transport of liquid digestate. The output of the bachelor thesis is a technical and economic evaluation that assesses the payback period depending on the flow of concentrated digestate. The specific costs for adjustment of liquid digestate with regard to the payback period are in the range of 5–15 years. The values do not exceed 210 (Kčyear)/t_fug . The values considering selling heat are even negative. The minimum value guaranteed by the manufacturer is around 260 (Kčyear)/t_fug . The integration of the evaporation system into Žamberk's biogas plant is economically disadvantageous. The thesis brings new knowledge about the potential of multi-stage flash evaporation in biogas plants with short transport distances and high utilization of waste heat.
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Membrane technologies for agricultural wastewater treatment
Uhlířová, Marcela ; Touš, Michal (referee) ; Vondra, Marek (advisor)
This thesis deals with an agricultural wastewater treatment (liquid digestate) by membrane technology. There is a fundamental description of characteristics of membrane technology with regard to application of agricultural wastewater treatment in this thesis. Experimental device for treatment of liquid digestate is designed and it consists of three steps – microfiltration, ultrafiltration and reverse osmosis. The first step consists of four filters with different pore sizes (80, 25, 10 and 5 µm). The second step is ultrafiltration and the third and key step is reverse osmosis. In the final step monovalent ions such as NH4+ are separated. Reverse osmosis consists of two stage system which results in higher recovery. Three experiments were carried out in order to verify the efficiency of separation dissolved solids.
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Phosphorus recovery from liquid digestate
Heger, Jan ; Procházková, Michaela (referee) ; Touš, Michal (advisor)
The focus of this thesis is the posibility of obtaining phosphorus from liquid digestate. The theoretical part of the thesis is focused on summarizing the current situation regarding phosphorus recovery. The research summarizes the essential information about the method of struvite precipitation, by which phoshphorus is obtained in the form of struvite, which can be further used as a fertilizer. Based on the process information, an experimental device was designed to obtain phosphorus in the form of struvite, corresponding to industry standards. It is a cylindrical vessel with a conical bottom, in which the liquid digestate with the chemicals is mixed with a stirrer. The functionality of the device was tested experimentally on the created device. The results of the experiment were analyzed by XPS method, which confirmed the formation of struvite. For future operation, modifications of the device and pre-treatment of the liquid digestate were proposed, which could improve the whole process and its results.
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Vliv digestátu na půdní sorpční komplex kambizemě
Doležalová, Eliška
The aim of this bachelor thesis is to determine the influence of applied fertilizers, specially digestate, on properties of soil sorption complex. The field experiment was established in 2014 at the plant research centre in Vatín near Žďár nad Sázavou. The vegetation cover was based on permanent grassland, maize monoculture and Norfolk cropping system. Types of fertilizers: anaerobic digestate, mineral (industrial) fertilizers and manure. The full fertilizer dose was 150 kg N / ha; P and K content are the same for all fertilizer variants. I determined hydrolytic acidity, base cation content, cation excange capacity and base cation saturation according to Kappen for samples from depths of 0 -10 cm and 10 - 20 cm.The application of digestate reduces hydrolytic acidity, increases the content of cations, cation exchange capacity, and the degree of saturation of sorption comlpex. These changes occur only at a depth of 0 - 10 cm.
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Stroje pro aplikaci digestátu
Zeman, Martin
The work deals with the first part of the existing machines for handling the digestate - drawn tanks and self-propelled applicators. It also deals with various variants of applicators and ancillary equipment used for application of digestate. It is also described by the quality of the selected machines and of the economic and technical evaluation of the application options. Followed by evaluation of field measurements focused on the absorption of nutrients in the soil, depending on the method of application. The last part of the work is optimization resulting from the measurement results.
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Hodnocení obsahu organických živin a epifytní mikroflóry u vybraných druhů trav
Sankot, Jiří
The work deals with the evaluation of nutrients and epiphytic microflora content in selected grass species Lolium perenne L., Phleum pratensis L., Festuca arundinaceae Schreb. and Lolium multiflorum Lam. X Festuca arundinacea Schreb. 2017 and 2018 at Vatín. The task was to determine the effect of fertilization doses by digestate, harvest year and species on organic nutrient content and epiphytic microflora. The content of nitrogenous substances, fats, fiber, ADF and NDF was evaluated from organic nutrients. The statistically significant (P <0.05) was the year for the effect on the crude protein content. Statistical significance (P <0.05) for fat content was demonstrated only in the species. For the proportion of fiber, ADF and NDF in fodder, the year of harvest, the type of fodder and the fertilizer variant had a statistically significant effect (P <0.05). The second evaluated area in forage was the epiphytic microflora. Only a fertilizer variant was statistically significant in CPM (P <0.05). The year of harvest and the fertilization variant were statistically significant (P <0.05) for BMK. The incidence of Enterobacteriaceae Enterobacteriaceae, the total number of micromycetes and yeasts was not statistically significant from any point of view. In fungi, fertilization was a statistically significant (P <0.05) variant. The effect of digestate fertilization on the amount of nutrients and microorganisms has not been evident.
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Stroje a strojní linky pro aplikaci fermentačního zbytku
Vondráček, Jan
The thesis deals with the topic of Machines and Machine Lines for the Application of Fermentation Residues in the theoretical part about the current trends in the application and handling of the fermentation residue, summarizes the input and output raw materials of BPS and related legislation. In addition, it deals in more detail with various variants of applicators and additional machines used for the application of solid and liquid fermentation residues. In the practical part the thesis is devoted to the evaluation of field - laboratory measurements oriented to the detection of nitrogen utilization from applied fermentation residues by plants. The final part is devoted to evaluating and optimizing the use of the method for practice.
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