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Darbo tikslas – įvertinti biodujų gamybos energetinį efektyvumą keičiant proceso temperatūrą. Šio darbo tyrimo objektas yra biodujų gamybos technologinis procesas. Darbe įvertinti svarbiausi anaerobinio proceso veiksniai ir jų įtaka gamybos procesui. Remiantis matematiniu modeliu, sukurta biodujų jėgainės energinio efektyvumo įvertinimo metodika. Teoriniuose tyrimuose nustatytos etanolio gamybos šalutinių produktų (žlaugtų) ir daugiamečių žolių siloso (paprastųjų šunažolių) mišinio perdirbimo į biodujas energijos sąnaudos prie šešių skirtingų temperatūrų. Eksperimentinių tyrimų metu nustatyta biodujų energinė vertė reaktoriui dirbant skirtingomis sąlygomis. Proceso temperatūrų režimai termofilinėje terpėje buvo nagrinėjami nuo 52 °C iki 57 °C, išlaikant kitus parametrus pastovius (sausųjų medžiagų koncentracija, organinės apkrovos ir įkrovos pH). Didžiausia biodujų išeiga iš etanolio gamybos šalutinių produktų (žlaugtų) ir daugiamečių žolių siloso (paprastųjų šunažolių) mišinio buvo gauta reaktoriuje palaikant 52 oC, su vidutine biodujų išeiga 674,4 l kg-1•SOM-1, su energetinė verte 14,19 MJ kg-1•SOM-1. Mažiausia biodujų išeiga ir energetinė vertė buvo gauta reaktoriuje palaikant 57 oC ir atitinkamai 512,3 l kg-1•SOM-1 ir 10,18 MJ kg-1•SOM-1. Bendrosios energijos sąnaudos priklausomai nuo temperatūros svyravo nuo 1562,6 MJ∙t-1 iki 1665,3 MJ∙t-1. Energetinis efektyvumas kito nuo 3,2 iki 4,9. / The energy balance of biogas production from industrial wastes and energy plants has been investigated during this research. Conversion efficiency of digestion of industrial wastes and energy plants to biogas by using different temperatures in range from 52 to 57 oC has been evaluated. Ratio, composition and pre-treatment technologies of mixtures of industrial by-products and energy plants were analyzed. The influence of temperature on the performance of anaerobic digestion of industrial wastes and energy plants has been investigated. The variation of temperatures ranges from 52 oC to 57 oC while keeping other parameters constant such as total solid concentration, organic load and pH. The highest biogas yield from industrial wastes and energy plants was found at 52 oC with average yield of 674,4 l kg-1•VS-1 and energy value of 14,19 MJ kg-1•VS-1. By rising temperature to 57oC there was a rapid initial drop in biogas yield rate averaging yield 512,32 l kg-1•VS-1 and energy value of 10,18 MJ kg-1•VS-1.In addition, the temperature fluctuations resulted variations of biogas production significantly. Total energy input ranged from 1563 MJ∙t-1 at 52 oC to 1666 MJ∙t-1 at 57 oC. Energy conversion ratio varied from 3,2 to 4,9.

This work was carried out at Biogas Research Center (BRC) and the company Biogas in Vadstena. The aim was to systematically evaluate new substrates for biogas production. In particular, this case investigated the potential of straw in co-digestion with manure and slurry from pig, chicken and dairy. Straw is interesting to evaluate since it is second generation biomass and available in a large quantity. Also, anaerobic digestion (AD) of manure is beneficial because it deals with the spontaneous methane emission and leads to a better manure handling. Goals within the EU as well as in Sweden have been set up to reduce greenhouse gas emissions from fossil fuel and to produce more renewable energy. The methodology used is outlined by BRC in which a number of key areas, such as description of biomass, amount biomass, gas yield, technology, economy, environmental performance and energy system, competing interests and institutional factors, have been evaluated through literature studies and case study Biogas in Vadstena. Based on the results an overall judgment is done to determine the potential of straw. The result shows that straw is not appropriate to digest solely because of high TS, high carbon content and lack of nutrients. Straw also has lignocellulosic structures, which are difficult to break down. Especially lignin limits the biodegradability. Mechanical, thermal, chemical and biological pretreatments can increase the availability and biodegradability in the straw. In some cases pretreatment can also increase the methane potential. However, straw works well as a carbon complement in co-digestion with manure, which is a nitrogen-rich substrate. There are technologies available for AD of straw and manure for the whole biogas process, from transportation and pretreatment to digestion and upgrading. Although, there is space for further development of pretreatment and upgrading technology. The economic calculations show that it is profitable to use straw with manure in a farm-based biogas plant for vehicle gas production. Furthermore, the calculations of the energy show that biogas production is energy efficient with energy input/output ratio of 18-23%. Besides production of biogas, the digestate could be used as an environmentally friendly fertilizer. In summary, it is possible to produce biogas from straw together with manure, and this is beneficial from both an environmental and economic perspective. / Detta examensarbete har utförts i samarbete med Biogas Research Center (BRC) och företaget Biogas i Vadstena. Målet med examensarbetet var att systematiskt utvärdera nya substrat för biogasproduktion. Specifikt för det här fallet var att undersöka potentialen för halm i samrötning med gödsel och flyt från svin, höns och nöt. Halm är intressant att utvärdera då det tillhör andra generationens biomassa och finns tillgängligt i stor mängd. Även rötning av gödsel är givande då den spontana metanemissionen uteblir och det ger en bättre gödselhantering. Det har satts upp mål inom såväl EU som i Sverige att mer förnybart bränsle bör produceras för att minska växthusgasutsläppen från fossila bränslen. Metodiken som använts har framarbetats av BRC. Det innebär att substrat granskas utifrån ett flertal nyckelområden, såsom beskrivning och mängd biomassa, gasutbyte, synergieffekter, teknik, ekonomi, miljöpåverkan och energisystem, konkurrerande intressen och institutionella faktorer. Dessa har utvärderats genom litteraturstudier och studie av fallet Biogas i Vadstena. Utifrån resultatet görs en övergripande bedömning av substratet. Resultatet visar att halm inte är lämpligt att röta enskilt på grund av högt TS-värde, högt kolinnehåll och att den är näringsfattig. Halm består även till stor del av lignocellosa-strukturer som är svåra att bryta ned, i synnerhet lignin. Mekaniska, termiska, kemiska och bioglogiska förbehandlingar kan öka tillgängligheten och nedbrytbarheten av halm. Det kan även öka metanpotentialen i vissa fall. Däremot fungerar halm bra som ett komplement i samrötning med gödsel som är ett kväverikt substrat. Det finns teknik för rötning av halm för hela biogasprocessen, från transport, förbehandling och rötning till uppgradering. Dock finns utrymme för tekniken att utvecklas ytterligare. De ekonomiska beräkningarna visar att det är lönsamt att använda halm tillsammans med gödsel i en jordbruksbaserad biogasanläggning för fordonsgasproduktion. Vidare visar beräkningar för energisystemet att biogasproduktion är energieffektiv med energi input/output-kvot på 18-23%. Förutom fordonsgas produceras även biogödsel som är ett miljövänligt alternativ till konstgjord gödsel. Sammanfattningsvis, det är möjligt att producera biogas av halm tillsammans med gödsel och det är fördelaktigt ur en såväl miljömässigt som ekonomiskt perspektiv.

Orientador: Ricardo Alan Verdú Ramos / Banca: João Batista Campos Silva / Banca: Eduardo Mirko Valenzuela Turdera / Resumo: No presente trabalho avalia-se uma opção para o aproveitamento energético do biogás gerado numa estação de tratamento de esgoto urbano, com capacidade de tratar os rejeitos provenientes de uma cidade de 1.000.000 de habitantes, através da instalação de um sistema de cogeração de energia, usando tecnologias baseadas em um conjunto turbina a gás e turbina a vapor (Caso 1) ou motor a gás e turbina a vapor (Caso 2), para produção de eletricidade para consumo próprio e de vapor para secagem do lodo. São realizadas análises termodinâmicas e termoeconômicas das duas plantas de cogeração propostas definindo-se índices de desempenho, como eficiências, custos unitários de produção eletricidade, calor e lodo seco, em função dos equipamentos utilizados e custos envolvidos com a implantação, operação e manutenção. Por fim, são realizadas análises econômicas das plantas propostas para verificação da viabilidade da implantação, levando-se em conta as receitas obtidas com a comercialização de créditos de carbono e de lodo como biofertilizante, bem como a diferença de custo entre a eletricidade gerada e a atualmente comprada. Dos indicadores estabelecidos e dos resultados obtidos, pode-se concluir que o primeiro caso parece significativamente mais atrativo do que o segundo. / Abstract: In the present work an option for the deployment of biogas energy generated at a urban sewage treatment plant with capacity to process the effluents from a city of 1,000,000 inhabitants is studied, considering the installation of a cogeneration power system, using technologies based on a gas turbine and steam turbine set (Case 1) or a gas IC engine and steam turbine set (Case 2), for production of electricity for own consumption as well as steam for drying the sewage residual sludge. Thermoeconomic and thermodynamic analysis are performed for both cogeneration plants proposed, setting up performance indicators, such as efficiencies, unitary costs for production of electricity, heat and dry mud, depending on the equipment and costs involved with the deployment, operation and maintenance. Finally, an economic analysis of the plants proposed is developed for verifying the feasibility of implementation, taking into account the proceeds from the sales of carbon credits and mud as biofertilizer as well as the difference between the costs of electricity generated and currently purchased. From the settings established and results obtained, it can be concluded that the first case seems to be significantly more attractive than the second. / Mestre

Orientador: Jorge de Lucas Junior / Banca: Vera Maria Barbosa de Moraes / Banca: Mônica Sarolli Silva de Mendonça Costa / Resumo: Objetivou-se a avaliação da produção e caracterização qualitativa de dejetos em sistemas de produção de ovos automatizado e convencional, bem como dos processos de compostagem e de biodigestão anaeróbia desses dejetos. Foram efetuadas quantificações diárias em conformidade com a rotina estabelecida na propriedade para os dois sistemas de produção. Para dejetos provenientes de sistemas automatizados encontrou-se uma produção de 0,10kg ave-1 dia-1 de matéria natural (MN) e 0,03kg ave-1 dia-1 de matéria seca (MS), para dejetos provenientes de sistemas convencionais armazenados sob as gaiolas de criação de galinhas por 260 dias a produção foi de 0,03kg ave-1 dia-1 (MN) e 0,025kg ave-1 dia-1 (MS) e quando avaliados com um dia de produção foi de 0,05kg ave-1 dia-1 (MN) e 0,02kg ave-1 dia-1 (MS). Após 90 dias de compostagem de dejetos de galinhas poedeiras, frescos (com e sem a adição de bagaço de cana-de-açúcar e serragem) e armazenados por 260 dias (com adição de bagaço de cana-de-açúcar e serragem), obteve-se redução de sólidos totais (ST) de 46,2%, 45,6% e 28,6%, respectivamente. Foram abastecidos biodigestores bateladas e contínuos com dejetos frescos e armazenados por 260 dias de galinhas poedeiras, ambos contendo 6% de ST e tempo de retenção hidráulica de 20 dias. Em ambas as fases, batelada e contínua, a maior produção de biogás foi para os dejetos frescos. As produções de biogás por kg de ST adicionados foram maiores para os biodigestores abastecidos com dejetos frescos, tanto em fase batelada quanto contínua (0,34m3. kg ST adicionados-1 e 0,45m3. kg ST adicionados-1, respectivamente) quando comparados com dejetos armazenados por 260 dias (0,28m3. kg ST adicionados-1 e 0,22m3. kg ST adicionados-1). / Abstract: The objective was to evaluate of the production and qualitative characterization of residues in conventional egg production and the automatic production system in commercial hen farms, composting and anaerobic bio-digestion. Daily quantifications were made in conformity to the routine management of the premises for the two production systems. In the automatic system the waste, production found was 0,10kg poultry-1 day-1 of natural matter (MN) and 0,03kg poultry-1 day-1 of dry matter (MS), wastes produced from conventional production system located under the cages of hens creation by 260 days, the production was 0,03kg poultry-1 day-1 (MN) and 0,025kg poultry-1 day-1 (MS) and when evaluated the daily production the waste found was 0,05kg poultry-1 day-1 (MN) and 0,02kg poultry-1 day-1 (MS). After 90 days of composting of poultry manure fresh (with and without the addition of sugar-cane pulp and sawdust) and stored by 260 days (with addition of sugar-cane pulp and sawdust), a reduction of total solids (TS) of 46,2%, 45,6% and 28,6%, was obtained respectively. Bio-digesters in batch and in daily load were supplied with fresh manure and stored by 260 days, both containing 6% of TS and hydraulic times' retention of 20 days. In both phases, batch and daily load, fresh manure was the largest producer of biogas. The biogas production per kg of added TS was larger for the bio-digestors supplied with fresh manure, both in batch phase and daily load (0,34m3. kg TS add-1 and 0,45m3. kg TS add-1, respectively) when compared with manure stored for 260 days (0,28m3. kg ST add-1 and 0,22m3. kg ST add-1). / Mestre

Orientador: Helenice de Oliveira Florentino Silva / Banca: Rui Vieira de Moraes / Banca: Ernane José Xavier da Costa / Resumo: Nos últimos anos, o setor agropecuário do Brasil vem se modernizando, e com isto provocando um aumento significativo na demanda de energia, no volume de dejetos animais e nos restos de cultura, ocasionando muitas vezes problemas de ordem sanitária, gerando desconforto e perigo à saúde devido o alto teor de substâncias patogênicas presentes nestes resíduos. Uma alternativa bastante eficiente para estes problemas é a reciclagem controlada destes resíduos em biodigestores, que podem converter os dejetos de animais de um problema em um benefício. Pois, a biodigestão resulta em dois subprodutos: um gás rico em metano denominado biogás e um fertilizante, uma espécie de lodo, que é o resíduo da matéria orgânica depois de fermentada, chamado biofertilizante. Desta forma, os biodigestores podem promover o suprimento de energia e fertilizante para os produtores rurais. Este trabalho enfoca a importância dos biodigestores em áreas rurais, apresenta técnicas que auxiliam tanto os projetistas como também os edificadores e operadores de biodigestores, discute os cálculos dos parâmetros para o projeto e construção de biodigestores, considerando os tipos e quantidades de resíduos presentes na propriedade rural e propõe um programa computacional para facilitar tais cálculos. / Abstract: Lately, the Brazilian farming and cattle rising sector has been improving it self, and hereby, promoting a significant rising on energy demand, on animal screments mass, and a culture residues. It often causes problems of sanitary character, producing discomfort and danger to health due to the strong content of pathogenic substances that appear in these residues. A very efficient alternative is the controlled recycling of these residues in the biodigestors, inverting the problem into benefits, since the biodigestion results in two derivates: an abundant gas in methane, named biogas, and a fertilizer, with a mire aspect, which is the organic matter residue after fermented, named biofertilizer. Thus, the biodigestors may promote energy and fertilizer supply for the agricultural producers. This work focuses on the importance of biodigestors in the field, introduces techniques that help both designers and biodigestor builders and operators. Besides, it discusses the calculus of parameters for the design and building of biodigestors, considering the kind and amounts of residues, which are present at the home farm. Finally, it presents computational software for favoring such calculus. / Mestre

Made available in DSpace on 2014-06-11T19:30:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-06Bitstream added on 2014-06-13T20:40:07Z : No. of bitstreams: 1 augusto_kz_me_jabo.pdf: 655578 bytes, checksum: 104c70aaf81ec126dfdb5aeb957bed18 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Funep / Objetivou-se a avaliação da produção e caracterização qualitativa de dejetos em sistemas de produção de ovos automatizado e convencional, bem como dos processos de compostagem e de biodigestão anaeróbia desses dejetos. Foram efetuadas quantificações diárias em conformidade com a rotina estabelecida na propriedade para os dois sistemas de produção. Para dejetos provenientes de sistemas automatizados encontrou-se uma produção de 0,10kg ave-1 dia-1 de matéria natural (MN) e 0,03kg ave-1 dia-1 de matéria seca (MS), para dejetos provenientes de sistemas convencionais armazenados sob as gaiolas de criação de galinhas por 260 dias a produção foi de 0,03kg ave-1 dia-1 (MN) e 0,025kg ave-1 dia-1 (MS) e quando avaliados com um dia de produção foi de 0,05kg ave-1 dia-1 (MN) e 0,02kg ave-1 dia-1 (MS). Após 90 dias de compostagem de dejetos de galinhas poedeiras, frescos (com e sem a adição de bagaço de cana-de-açúcar e serragem) e armazenados por 260 dias (com adição de bagaço de cana-de-açúcar e serragem), obteve-se redução de sólidos totais (ST) de 46,2%, 45,6% e 28,6%, respectivamente. Foram abastecidos biodigestores bateladas e contínuos com dejetos frescos e armazenados por 260 dias de galinhas poedeiras, ambos contendo 6% de ST e tempo de retenção hidráulica de 20 dias. Em ambas as fases, batelada e contínua, a maior produção de biogás foi para os dejetos frescos. As produções de biogás por kg de ST adicionados foram maiores para os biodigestores abastecidos com dejetos frescos, tanto em fase batelada quanto contínua (0,34m3. kg ST adicionados-1 e 0,45m3. kg ST adicionados-1, respectivamente) quando comparados com dejetos armazenados por 260 dias (0,28m3. kg ST adicionados-1 e 0,22m3. kg ST adicionados-1). / The objective was to evaluate of the production and qualitative characterization of residues in conventional egg production and the automatic production system in commercial hen farms, composting and anaerobic bio-digestion. Daily quantifications were made in conformity to the routine management of the premises for the two production systems. In the automatic system the waste, production found was 0,10kg poultry-1 day-1 of natural matter (MN) and 0,03kg poultry-1 day-1 of dry matter (MS), wastes produced from conventional production system located under the cages of hens creation by 260 days, the production was 0,03kg poultry-1 day-1 (MN) and 0,025kg poultry-1 day-1 (MS) and when evaluated the daily production the waste found was 0,05kg poultry-1 day-1 (MN) and 0,02kg poultry-1 day-1 (MS). After 90 days of composting of poultry manure fresh (with and without the addition of sugar-cane pulp and sawdust) and stored by 260 days (with addition of sugar-cane pulp and sawdust), a reduction of total solids (TS) of 46,2%, 45,6% and 28,6%, was obtained respectively. Bio-digesters in batch and in daily load were supplied with fresh manure and stored by 260 days, both containing 6% of TS and hydraulic times’ retention of 20 days. In both phases, batch and daily load, fresh manure was the largest producer of biogas. The biogas production per kg of added TS was larger for the bio-digestors supplied with fresh manure, both in batch phase and daily load (0,34m3. kg TS add-1 and 0,45m3. kg TS add-1, respectively) when compared with manure stored for 260 days (0,28m3. kg ST add-1 and 0,22m3. kg ST add-1).

The subject of this thesis is to evaluate investments in biogas plant purchased by company AGRA Deštná, a.s., which is located in Deštná, near Jindřichův Hradec. The thesis is divided into two main parts. The theoretical part is devoted to theoretical assumptions of investment evaluation, grants, theories and legislation related to the biogas plant. The practical part of the thesis describes the current situation of the company, investment, and economic evaluation of investment in the construction of biogas plants.

The thesis handles the problem of biogas purification by membrane separation method, and its application on existing biogas plants. Assessing of impacts of this implementation is carried out from technical and economical point of view.

This thesis focuses on the analysis of heat efficiency and effectiveness of the Vojtěchov biogas station unit. The material balances were developed in connection with biogas created in the cogeneration unit. The heat produced by the cogeneration unit is distributed to reactors and drying rooms. Pursuing the main goal of the thesis, the research of the complete heating balance for all months has been conducted. Additionally, a variety of options were assessed, to find the best solution of how to increase the effectivity of the heat. As for the final solution, two recommendations have been proposed in the thesis. The first recommendation lies in a better usage of low-level heat distributed to the secondary fermentor. The second suggestion deals with the amount of heat from cogeneration unit to the system. The result of the analysis is the final recommendation on how to increase the efficiency of the heat usage and potential impacts of the solution on the subsidy according to the KVET standards received in the given year.