|
|
Energy balance of biomass heating plant
Žmolík, Václav ; Šen, Hugo (referee) ; Baláš, Marek (advisor)
This thesis deals with a design of a biomass heating plant combinating a Rankin-Clausius cyklus and a CHP unit. The CHP unit fuel is a biogas and the boiler fuel is a wooden chip. The adapted CHP unit regenerates feed-water of the R-C cycles. This design is technicaly and economicalty compared with the Rankin-Clausius cycle without feed-water regeneration by the CHP unit.
|
|
|
Performance of the system for energy utilization from biomass
Koláček, Richard ; Máša, Vítězslav (referee) ; Pavlas, Martin (advisor)
This diploma thesis deals with the problems associated with acquisition of experimental data from technological unit for biomass combustion with nominal capacity of 1 MW, with regard to determination of thermal efficiency. In the introduction part, parameters of currently available biomass-based fuels as well as of those with large potential in the future are summarized. Further, a review in the field of biomass combustion technology is given. Biomass boilers are compared according to their technical parameters, function and benefits and drawbacks. In theoretical part methods for determination of thermal efficiency by direct method, indirect method and modified indirect method are described. Main parameters influencing resultant values of efficiency are included into the analysis. In final part an evaluation of real operational data from prototype unit combusting wooden chips is made. Recommendations for further experimental data gathering and their processing with the aim to evaluate thermal efficiency are suggested.
|
|
|
Boilers with medium capacity for biomass combustion of czech and foreign production
Habán, Tomáš ; Kropáč, Jiří (referee) ; Pavlas, Martin (advisor)
The main objective of this work is to focus on biomass as one of the components of renewable energy sources for the production of thermal energy by combustion. The introduction of work maps the current state of biomass used in the Czech Republic. It evaluates options for future uses for biomass and also the size of the potential in the natural conditions of the Czech Republic. It also views this renewable resource from the point of view of energy conception and evaluace the government positron on this issue. Next part deals with the combustion of biomass and with the use of created thermal energy. It ruminate a problem of pollutants and shows values for emission limits results from the legislation. It shows ways of using this thermal energy and the associated production of electrical energy including an overview of the possibilities of its evaluation. The last part of this work describes a comparison between biomass boilers from Czech and foreign producers in the range of rated output 1 to 3 MW. It divides boilers in terms of legislation and shows the obligations and conditions attached to the operators of biomass boilers. It outlines the biggest application of boilers with medium capacity for biomass combustion in the Czech Republic.
|
|
|
Emissions from biomass combustion
Vaněk, Michal ; Lisá, Hana (referee) ; Baláš, Marek (advisor)
The thesis deals with harmful substances originating as products of biomass combus-tion and possibilities of reducing their emissions from boilers for household heating. First of all, biomass is introduced and a description of important fuel properties in terms of its combustion is given. Secondly, the characteristic of the combustion process and origination mechanisms of individual substances are presented. This is followed by a description of the properties of these substances and their impacts on human health and the environment. The purpose of the next chapter is to present the reader with current legislation addressing the emissions of small boilers. Then a separate chapter describes possible methods that can be used to reduce emissions of these devices. Finally, several measures in the form of modifications and devices, capable of reducing harmful emissions of small boilers are given.
|
|
|
Mathematical Model of Biomass Boiler for Control Purposes
Máša, Vítězslav ; Klemeš,, Jiří (referee) ; Olehla, Miroslav (referee) ; Švarc, Ivan (advisor)
he thesis focuses on building of dynamic mathematical model of biomass boiler as a controlled system and the use of this model in practise. At the first part of the thesis the area of energy production using biomass is introduced and the current development at the area of the automatic control of biomass boilers with medium energy output (in units of MW) is described. Although the main topic of the thesis is the construction of model of biomass boiler for control purposes, thesis deals with technology of boilers and principles of its inner processes as well. Creation of the model comes out not only from these important findings, but also from experimental data collected during measurements in real operation. Heat and mass balance calculations were made according to these data and they serve to precise static properties of experimental unit for biomass combustion. Central part of the thesis presents development of the final model that resulted from balance calculations and from step responses of the system obtained by measuring. Built dynamic model is compared with experimental data through simulations in Simulink and verified. At the next part the model of controlled system is completed with control system and closed-loop control circuit is validated and verified by simulation. Then the design of new controller configuration, which improves the quality of control considerably, is presented. At the final part of the thesis, possibilities of other use of the model of boiler are given, both in control theory and in industrial practice.
|
|
|
Temperature field in solid fuel
Ptáček, Pavel ; Šnajdárek, Ladislav (referee) ; Pospíšil, Jiří (advisor)
The diploma thesis deals with a temperature field in a solid fuel during the combustion process. At the beginning of this thesis, research of available literature was conducted to obtain information about the composition of wood, properties affecting the combustion process, and the basics of heat transfer. Afterward, the temperature profiles of the samples were recorded during the measurement in the observation furnace. The temperature profiles of samples of six different sizes which were made of spruce and beech wood were subsequently evaluated and compared. Based on experimentally obtained data, a mathematical model was created in the OpenModellica software. Finally, the results of the mathematical model were compared with experimentally obtained data and appropriate conclusions were deduced.
|
|
|
Toxicity of fine and ultrafine particles from combustion processes
Berková, Helena ; Köbölová, Klaudie (referee) ; Adamec, Vladimír (advisor)
The bachelor thesis deals with the toxicity of fine and ultrafine particles from biomass combustion. The theoretical part is focused on the current state of this issue from the origin, physicochemical properties, mechanism of toxicity of particles, to their impact on the environment and human health. The following is an overview of tests for determining the toxicity of fine and ultrafine particles. The experimental part is devoted to the actual sampling of biomass combustion, their characterization, cultivation of the tested organism and toxicity tests. The results of acute toxicity tests are expressed in terms of percentage mortality values and then the toxicity is evaluated.
|
|
|
Electrostatic precipitator for household wood firing boiler
Preisler, Lukáš ; Skála, Zdeněk (referee) ; Brázdil, Marian (advisor)
This diploma thesis aims on the development of an experimental electrostatic precipitator for household wood firing boiler. First, a literature review was conducted, aiming on the description of the precipitator using physical relations and, on its basis, a numerical model was created. By applying the numerical model, the precipitator configuration was designed as well as the engineering design of the whole system. The chosen configuration was validated by measurement using the corona discharge starting at voltage of 6,5 kV. By applying modifications, the electrostatic precipitator was built and tested during a running boiler. Due to flue gas condensation and load, corona discharge did not initiate, and the parameters were not validated. Modifications in the construction design were suggested leading to launch the electrostatic precipitator. The main requirement is a surface finishing of wire hinging components.
|
|
|
The environmental aspects of biomass boilers operation
Slavíček, Martin ; Urban, Lukáš (referee) ; Pavlas, Martin (advisor)
The content of this thesis focuses on the subject of biomass usage for energetic purposes. The introduction deals with the renewable energetic resources and their utilization and utilization of the biomass as a fuel, its division and characteristics. The following part deals with the legislation in the Czech Republic for the machinery used for combustion of biomass and its standards. Examples of different technology used in boilers and generators for biomass is mentioned as well. Then the biomass emissions with their specific values are discussed.
|
|
| |
guest ::
