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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

Estudo do desempenho energético das caldeiras da indústria de polpa celulósica kraft / Study of energy performance of boilers from kraft pulp industries

Kravetz, Carolina 13 August 2018 (has links)
A importância da energia elétrica gerada pelo setor de celulose e papel têm crescido no mercado brasileiro, pois com a crise hídrica que tem causado transtornos financeiros aos diversos setores da economia, muitas empresas têm optado por ter a geração de energia como um novo plano de negócio. Desta forma, para que esta produção cresça são necessários investimentos nessa área. Por isso, é essencial conhecer o processo, bem como os parâmetros envolvidos na produção de energia. Com a finalidade de ampliar os conhecimentos da área de energia dentro do setor de celulose e papel, este trabalho teve como objetivo identificar a relação dos parâmetros das caldeiras de recuperação e biomassa, bem como de seus combustíveis, afim de determinar sua influência na produção de vapor. Para isso, foram utilizados os valores dos parâmetros das caldeiras de recuperação e biomassa, entre eles: consumo de combustível, vazões de ar, temperaturas da água de alimentação e do vapor gerado, como também os valores das características químicas e físicas do licor negro, incluindo poder calorífico superior, teor de sólidos totais, teor de orgânicos e inorgânicos, e da biomassa, densidade aparente, poder calorífico superior, umidade e teor de cinzas. Os parâmetros e as características dos combustíveis foram disponibilizados por uma empresa do setor de celulose e papel do Brasil. Para análise e discussão dos dados foram feitos cálculos de eficiência energética, análise de diagramas de dispersão, correlação de Pearson, elaboração de modelos matemáticos para estimativa de produção de vapor e a determinação dos valores ideais dos parâmetros dos combustíveis, para produção máxima de vapor. A partir das análises de eficiência energética, a caldeira de recuperação manteve uma média de 86%, enquanto que a caldeira de biomassa obteve uma média de 51%. Analisando as relações entre todos os parâmetros, nas caldeiras as variáveis com maior influência na operação foram as vazões de ar, vazão da água de alimentação, o consumo de combustível, temperatura da água de alimentação, temperatura dos gases de saída e a pressão do vapor, enquanto que nos combustíveis a maior influência foi do poder calorífico superior. Dentre os modelos matemáticos analisados para a predição da produção de vapor, apenas o modelo utilizando parâmetros da caldeira de recuperação foi estatisticamente significativo. Através da análise das características dos combustíveis, relacionando-as com o objetivo de obter a máxima produção de vapor, os valores ideais calculados destas características químicas e físicas do licor negro e da biomassa se mantiveram de acordo com a literatura. / The importance of the electric energy generated by the pulp and paper sector has grown in the Brazilian market, because the water crisis has caused financial distress to the various sectors of the economy, and then many companies have chosen to have the power generation as a new business plan. In this way, for this production to grow, investments in this area are necessary. Therefore, it is essential to know the process as well as the parameters involved in energy production. With the purpose of increasing the knowledge of the energy area within the pulp and paper sector, this work aimed to identify the relation of the parameters of recovery and biomass boilers, as well as their fuels, in order to determine their influence in the production of steam. In order to do this, the values of the parameters of the recovery and biomass boilers were used, among them: fuel consumption, air flows, feed water and steam temperatures, as well as the values of the chemical and physical characteristics of the black liquor, including higher calorific value, total solids content, organic and inorganic content, and of biomass, apparent density, higher calorific value, moisture and ash content. The parameters and characteristics of fuels were made available by a Brazilian pulp and paper company. In order to analyze and discuss the data were made energy efficiency calculations, dispersion diagrams analysis, Pearson correlation, mathematical models for estimation of steam production and determination of the ideal values of the fuel characteristics for maximum steam production. From the energy efficiency analyzes, the recovery boiler maintained an average of 86%, while the biomass boiler obtained an average of 51%. Analyzing the relationships among all parameters, the variables with the greatest influence on the operation were air flow, feed water flow, fuel consumption, feed water temperature, outlet gas temperature and steam pressure, while in fuels the greatest influence was the higher calorific value. Among the mathematical models analyzed for the prediction of steam production, only the model using parameters of the recovery boiler was statistically significant. Analyzing the characteristics of the fuels in order to obtain the maximum steam production, the estimated ideal values of these chemical and physical characteristics of black liquor and biomass were kept in agreement with the literature.
62

Návrh roštového kotle s přirozenou cirkulací na spalování kontaminovaného dřeva / Design of steam boiler with grate firing burning contaminated wood

Král, Ondřej January 2017 (has links)
The master´s thesis deals with steam boiler design that burns contaminated wood with output 55 tons of steam per hour, steam pressure 4,2 MPa and temperature 423 °C. First two chapters focuses on stoichiometry and calculation of heat losses and boiler efficiency. Great part of thesis constitutes of thermal and dimensional calculations of every heat transfer surface. Some specific boiler parts are described considering special fuel properties. Final chapters contain pressure losses calculation of flue gas and heated medium for pumps and fans design. Drawing is also part of the work which is included as an attachment.
63

Návrh tepelného zdroje lokální soustavy CZT / Design of the heat source of the local district heating system

Svobodová, Veronika January 2019 (has links)
The diploma thesis is focused on district heat supply, heat sources, machinery and safety equipment of boiler rooms. The main goal of the thesis is to modernize parts of the heat sources with the respective boiler room equipment in accordance with the latest available technology. The generated thermal energy is used for heating or hot water production for residential and non-residential buildings in the vicinity of the boiler room. In the theoretical part, the thesis focuses in more detail on boiler rooms, specifically on heat energy sources, machinery and safety equipment of boiler rooms, system ventilation and combustion exhaust. The findings are applied in the design of the new boiler room layout. It is followed by a detailed description of the current state of the boiler room and heat networks. An essential part of the work is the assessment of layout of the current heat sources and the creation of a new design for the replacement of insufficient sources and related equipment. The last goal is an economic overview of the designed project solution.
64

Roštový kotel na spalování dřevní štěpky a tříděného odpadu 50t/h / RDF Grate Biomass Boiler

Malíková, Veronika January 2020 (has links)
The diploma thesis deals with the design of a grate boiler for the combustion of a mixture of RDF and wood chips with the specified output and parameters of superheated steam. The introduction consists of stoichiometric calculations and determination of the thermal efficiency of the boiler. The thesis is devoted to determining the dimensions of the boiler, heat transfer calculations, determining pressure losses, checking the heat balance and chlorine corrosion.
65

Návrh vytápění a větrání pro rekonstruovaný rodinný dům / Heating and ventilation in a renovated family home

Nejerál, Michal January 2021 (has links)
The main goal of the diploma thesis is to design a new ventilation and heating system in an old house after its reconstruction. The design also includes consideration of the possibility of using renewable resources. A central heat recovery ventilation systém is designed to ensure ventilation of the building. The heating design is based on two independent heat sources. It is a wood boiler and a gas condensing boiler. After considering renewable sources, a photovoltaic system is designed. The results of individual calculations and drawing documentation of designs are also attached.
66

Modularní horizontální kotel – HRSG / Modular Horizontal Heat Recovery Steam Generator

Primes, Alois January 2021 (has links)
This thesis deals with the design of a Heat Recovery Steam Generator (HRSG). Theintroductory part is devoted to a brief description of the boiler, the specified parametersand the compilation of the temperature profile. The main computational part of thiswork is divided into 6 parts. The first contains preparatory calculations, including thecalculation of boiler eiciency. In the second part, a flue gas duct is designed. This isfollowed by a thermal calculation of the boiler for all heat exchange surfaces. The last 3parts deal with the design of the drum, piping and the loss of boiler draft calculation.
67

Budišov-studie kotelny na biomasu / Budisov-Biomass heating plant

Petrovský, Jiří January 2008 (has links)
This dissertation contains a comparison of the real possibilities for heating reconstruction and TUV reheating in three public buildings (located nearby one another) in Budišov township, with resulting recommendations of the best options for local operating conditions. The dissertation contains calculations of heating requirements for particular buildings, a generic theoretical part which summarizes basic data concerning long-term fuels (biomass and natural gas), proposals for technical solutions to heating sourcing concerning these fuels and its prospective distribution from a central boiler house, and its reciprocal comparison from the perspective of the economics of actual realization and operation, and from a perspective of fuel availability and ecology.
68

Změna palivové základny kotle John Thomson / Change John Thomson boiler fuel base

Hradecký, Martin January 2012 (has links)
This Thesis deals with thermal control calculation of the existing John Thomson steam boilers burning heating mazut and subsequent thermal conversion to natural gas. The main parts of the calculation are as follows: stoichiometry, thermal balance, conversion of the combustion chamber and heating area.
69

Návrh parního kotle na spalování hnědého uhlí, parametry páry 235 t/h, 14 MPa, 540°C / Stean boiler for sub bituminous coal, steam parametres 235 t/h, 14 MPa, 540°C

Horák, Stanislav January 2014 (has links)
The aim of the work is to design a brown coal combustion boiler of 235 t/h output. The work is divided into several parts. First, stechiometric calculations and calculations enthalpy of air and flue gas are performed. It is calculated heat balance of the boiler, the boiler losses and the thermal efficiency of the boiler is determined. After designing the combustion chamber thermal calculation is made. Then, individual heating surfaces are proposed and at the end of the calculations are controlling the overall energy balance of the boiler. For calculation was design documentation added.
70

Navrhněte parní kotel s přirozenou cirkulací na spalování dřevní štěpky / Steam boiler with natural cirkulation for wood cheaps burning

Vaculík, Jaroslav January 2014 (has links)
The purpose of this Diploma Thesis is the construction design of the steam boiler with natural circulation for the combustion of wood biomass according to the specified parameters. It is the boiler with the power of 12 tons per hour of superheated vapor output parameters of 3,3 Mpa at a temperature of 400 °C and a temperature of feed water 105 °C. For the specified parameters I first calculated the stoichiometric calculations, boiler efficiency, and followed by using geometrical parameters of the blocks and thermal calculations set design and the number of heat transfer surfaces, depending on the input parameters of the air and water and output parameters of vapor. The work also includes drawings of the boiler.

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