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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.
1

Utilização de biogás de estações de tratamento de esgoto para fins energéticos / Use of Biogas Wastewater Treatment Plants for Energy Purposes.

Silva, Thaisa Carolina Ferreira 25 March 2015 (has links)
O aproveitamento energético do metano corresponde a uma das opções mais interessantes de utilização deste subproduto do tratamento de esgotos domésticos que é um gás de médio poder energético e também um gás indutor de efeito estufa (GEE). Esta dissertação visa estudar as perspectivas concretas de geração de eletricidade a partir da recuperação e do uso do biogás oriundo do processo de tratamento anaeróbio de esgotos domésticos mediante atualização dos marcos regulatórios brasileiros e levantamento experimental das taxas de produção de biogás em Estações de Tratamento de Esgotos (ETEs). Nesse contexto, foram quantificadas, em tempo real, as taxas de produção de biogás e de metano de uma ETE de grande porte (3556,8 m3 tratados/hora), contendo 16 reatores UASB, alimentados com esgotos domésticos. Os resultados apontaram uma grande variação na carga orgânica recebida (37.948 ± 11.993) kg/dia e na vazão de biogás da ETE (84,30 ± 26,64) Nm3/h, que podem ser influenciadas negativamente por eventos de chuva. De modo geral, as quantidades médias de vazão de biogás estimadas em estudos foram maiores que aquelas registradas a partir de medições, dependendo do método utilizado tal quantidade pode ser até 10 vezes maior que aquela verificada a partir de medições de campo. A potência elétrica máxima calculada em 233 kW se mostrou próxima da autossuficiência da ETE e as novas diretrizes regulatórias podem permitir a compensação de energia de outras ETEs do sistema. As emissões de metano podem reduzir significativamente, cerca de 7.476,7 t CO2eq, quando do aproveitamento energético e possibilitam a venda de Certificados de Emissões Evitadas de Carbono. Conclui-se que, com o planejamento adequado, é possível haver interação entre saneamento ambiental e geração de energia com benefícios para ambos os setores. / The energy use of biogas corresponds to one of the most interesting use options of this by-product of wastewater treatment which is a mean-energy power and also a greenhouse gas. In this sense, this work aims to study the concrete prospects for electricity generation from the recovery and use of biogas derived from process of anaerobic treatment of wastewater by updating the Brazilian regulatory frameworks and experimental survey of biogas production rates in Wastewater Treatment Plants (WTP). In this context, were quantified in real time, biogas and methane production rates of a large WTP (3556.8 m3 treated / hour) containing 16 UASB reactors fed with domestic wastewater. The results showed a wide variation in the incoming organic load (37.948 ± 11.993) kg/dia and flow of biogas and methane from WTP (84,30 ± 26,64) Nm3/h, which can be negatively influenced by rainfall events. In general, the average quantities of biogas flow studies were estimated at greater than those recorded from measurements depending on the method used such amount can be up to 10 times higher than that found from field measurements. The maximum electric power estimated at 233 kW proved close to the WTP self-sufficiency and the new measures taken by the regulatory guidelines could allow power compensation in other WTPs system. Methane emissions can significantly reduce, about 7.476,7 t CO2eq, when the biogas was used for energy generation and may allow the sale of Avoided Carbon Emissions Certificates. So it is concluded that, with proper planning, it is possible to have interaction between environmental sanitation and power generation with benefits for both sectors.
2

Utilização de biogás de estações de tratamento de esgoto para fins energéticos / Use of Biogas Wastewater Treatment Plants for Energy Purposes.

Thaisa Carolina Ferreira Silva 25 March 2015 (has links)
O aproveitamento energético do metano corresponde a uma das opções mais interessantes de utilização deste subproduto do tratamento de esgotos domésticos que é um gás de médio poder energético e também um gás indutor de efeito estufa (GEE). Esta dissertação visa estudar as perspectivas concretas de geração de eletricidade a partir da recuperação e do uso do biogás oriundo do processo de tratamento anaeróbio de esgotos domésticos mediante atualização dos marcos regulatórios brasileiros e levantamento experimental das taxas de produção de biogás em Estações de Tratamento de Esgotos (ETEs). Nesse contexto, foram quantificadas, em tempo real, as taxas de produção de biogás e de metano de uma ETE de grande porte (3556,8 m3 tratados/hora), contendo 16 reatores UASB, alimentados com esgotos domésticos. Os resultados apontaram uma grande variação na carga orgânica recebida (37.948 ± 11.993) kg/dia e na vazão de biogás da ETE (84,30 ± 26,64) Nm3/h, que podem ser influenciadas negativamente por eventos de chuva. De modo geral, as quantidades médias de vazão de biogás estimadas em estudos foram maiores que aquelas registradas a partir de medições, dependendo do método utilizado tal quantidade pode ser até 10 vezes maior que aquela verificada a partir de medições de campo. A potência elétrica máxima calculada em 233 kW se mostrou próxima da autossuficiência da ETE e as novas diretrizes regulatórias podem permitir a compensação de energia de outras ETEs do sistema. As emissões de metano podem reduzir significativamente, cerca de 7.476,7 t CO2eq, quando do aproveitamento energético e possibilitam a venda de Certificados de Emissões Evitadas de Carbono. Conclui-se que, com o planejamento adequado, é possível haver interação entre saneamento ambiental e geração de energia com benefícios para ambos os setores. / The energy use of biogas corresponds to one of the most interesting use options of this by-product of wastewater treatment which is a mean-energy power and also a greenhouse gas. In this sense, this work aims to study the concrete prospects for electricity generation from the recovery and use of biogas derived from process of anaerobic treatment of wastewater by updating the Brazilian regulatory frameworks and experimental survey of biogas production rates in Wastewater Treatment Plants (WTP). In this context, were quantified in real time, biogas and methane production rates of a large WTP (3556.8 m3 treated / hour) containing 16 UASB reactors fed with domestic wastewater. The results showed a wide variation in the incoming organic load (37.948 ± 11.993) kg/dia and flow of biogas and methane from WTP (84,30 ± 26,64) Nm3/h, which can be negatively influenced by rainfall events. In general, the average quantities of biogas flow studies were estimated at greater than those recorded from measurements depending on the method used such amount can be up to 10 times higher than that found from field measurements. The maximum electric power estimated at 233 kW proved close to the WTP self-sufficiency and the new measures taken by the regulatory guidelines could allow power compensation in other WTPs system. Methane emissions can significantly reduce, about 7.476,7 t CO2eq, when the biogas was used for energy generation and may allow the sale of Avoided Carbon Emissions Certificates. So it is concluded that, with proper planning, it is possible to have interaction between environmental sanitation and power generation with benefits for both sectors.
3

Effect of Temperature on Biogas Production in Anaerobic Treatment of Domestic Wastewater UASB System in Hammarby Sjöstadsverk.

Zhao, Chengyuan January 2011 (has links)
The upflow anaerobic sludge blanket (UASB) reactor is widely used around the world to treat variety of domestic andindustrial wastewater with three main advantages: production of biogas as renewable energy, no need of support structure for development of microorganisms and high rate treatment efficiency with low rate of biomass production. This study evaluates the effect of temperature on biogas production and CODtotal removal in Line 4-UASB system treating domestic wastewater in Hammarby Sjöstadsverk. Eight parameters were examined including the following: Influent and effluent temperature, pH, influent CODtotal, influent rate, effluent CODtotal, volatile fatty acids, biogas production rate and methane concentration. There are eight set temperature and each is stabilized for seven days. The biogas production analysis is focus on UASB 1. Temperature rising from 19°C to 35°C achieves a general benefit result in methane yield rate and CODtotal removal efficiency. The best methane yield rate and CODtotal removal rate are 0.167l/gCODtotal and 56.84% respectively at highest working temperature 33.4°C with OLR 3.072gCODtotal/(l*day) and HRT 4.2h. / Den ökande energiförbrukningen i världen och utsläpp av växthusgaser (GHG) gör det nödvändigt att söka nya hållbara energikällor för att matcha efterfrågan på energi i framtiden. Rötningsteknik med organiskt avfall som förnybar energikälla, ger biogas som i genomsnitt består av 78% CH4, 22% av CO2och spår av H2S (<0.5%), är en idealisk kostnadseffektiv metod. Den Uppåt flödande anaeroba slambäddsreaktorn(UASB) med största fördelarna: biogasproduktion som förnybar energi, hög belastning och hög behandlingseffektivitet med låg produktion av biomassa, inget behov av stödstruktur för utveckling av mikroorganismer, är den viktigaste typen för anaerobt reningssystem. Det finns flera faktorer som påverkar UASB-reaktorns prestanda, såsom temperatur, pH, HRT, Uppåtriktat flödeshastighet, OLR, SRT och VFA. I denna studie är huvudsyftet att med fokus på utvärdering av temperaturpåverkan på biogasproduktion och CODtotal avlägsnat i UASB-systemet Linje 4 som behandlar hushållsspillvatten i Hammarby Sjöstadsverk. Analysen avbiogasproduktionen fokuserades på UASB reaktor 1. Åtta parametrar övervakades för att kontrollera skick inklusive inflöde och utflöde, temperatur, pH, CODtotal inflöde, strömningshastighet för inflöde, CODtotal utflöde, flyktiga fettsyror VFA, biogasproduktionstakt och metankoncentration. Försöken utfördes vid åtta inställda temperaturnivåer och varje nivå stabiliserades i sju dagar. pH och VFA-värde var stabilt under hela försöket. Resultatetvisar att temperaturen har en större inverkan på metanavkastningen och CODtotal avlägsnat än belastningen, OLR. Då temperaturen höjs från 19°C till 35°C erhålls en större metanavkastning och större CODtotal avlägsnat. Den största metanavkastningen och CODtotal avlägsnat är 0,167l/g CODtotal respektive 56.84% vid den högsta arbetstemperaturen 33.4°C med OLR 3.072g CODtotal/(l * dag) och HRT 4.2h. Energibalansen vid olika arbetstemperaturer visaratt det finns en stor skillnad i energibehov för uppvärmning och utbyte avenergi i form av biogas. För att minska klimatpåverkan och nå balans mellan input och output av energi måste energibehovet för uppvärmning reduceras. Energiåtervinning från utflöde till inflöde liksom drift av UASB vid låg temperatur är ämnen som kan studeras vid fortsatt arbete.
4

Avaliação do desempenho de dois reatores anaeróbios horizontais de leitos fixos (RAHLF), um contendo biomassa auto-imobilizada e outro contendo suporte de espuma de poliuretano, no tratamento de água residuária de indústria de refrigerante / not available

Moraes, Valmir de 27 September 2002 (has links)
O uso de reatores de biomassa imobilizada para tratamento de esgoto tem se difundido devido a sua capacidade de manter o tempo de retenção celular (TRC) elevado, mesmo quando operados com baixo tempo de detenção hidráulica (TDH). Neste trabalho, investigou-se o desempenho de dois reatores anaeróbios horizontais de leito fixo (RAHLF) em escala de bancada, usados no tratamento do efluente de uma indústria de refrigerantes, sendo um dos reatores preenchido com grânulos e o outro com espuma de poliuretano. A pesquisa foi dividida em três etapas, referentes aos tempos de detenção hidráulica (TDH) de, respectivamente, 20 h, 10 h e 5 h. O encerramento de cada etapa ocorria quando se verificava a estabilidade operacional do sistema através dos parâmetros: DQO, ácidos voláteis totais e pH. Ao final de cada etapa, foram obtidos os perfis de concentração de DQO ao longo dos reatores. Para TDH de 10 h, os valores obtidos para a constante cinética aparente (klapp) foram de 0,694 h-1, para o reator com grânulos, e de 0,467 h-1, para o reator preenchido com espuma de poliuretano. No decorrer da pesquisa, os reatores apresentaram alguns problemas operacionais, que aumentaram à medida em que se reduzia o TDH. Avaliou-se, também, o tempo de residência real do reator com espumas através de experimentos hidrodinâmicos (traçadores). Ao final do experimento, foram quantificados os sólidos voláteis em cada reator e buscou-se diferenciar o arranjo e a fauna microbiológica, presentes nos dois tipos de imobilização, através de microscopia eletrônica de varredura (MEV). / Immobilized biomass reactors have been increasingly used for wastewater treatment due to their capacity of maintaining high cellular retention time (CRT) even when operating at low hydraulic detention time (HDT). In this work, the performances of two horizontal-flow anaerobic immobilized biomass (HAIB) bench-scale reactors treating soft drinks industry effluents were investigated and compared. One of the reactors was filled with granules and the other one with polyurethane foam matrices. The research was conducted in three stages, concerning to hydraulic detention times of, respectively, 20 h, 10 h and 5 h. A stage was considered finished when reactors operational stability was checked by means of COD, total volatile fatty acids and pH. COD profiles were obtained along the reactors at the end of each stage. In the second stage, when HDT was equal to 10 h, the apparent kinetic constant (klapp) values were 0.694 h-1, to the reactor filled with grains, and 0.467 h-1, to the other one. During the research, the reactors showed some operational problems, that increased when the HDT was reduced. The real hydraulic detention time (HDT) reactor with polyurethane foams was evaluated through the hydrodynamic experiments (tracers). Volatile solids of each reactor were quantified at the end of experiment. The arrangement and microbiological fauna inside the reactors were determined by Scanning Electron Microscopy (SEM).
5

Avaliação do desempenho de dois reatores anaeróbios horizontais de leitos fixos (RAHLF), um contendo biomassa auto-imobilizada e outro contendo suporte de espuma de poliuretano, no tratamento de água residuária de indústria de refrigerante / not available

Valmir de Moraes 27 September 2002 (has links)
O uso de reatores de biomassa imobilizada para tratamento de esgoto tem se difundido devido a sua capacidade de manter o tempo de retenção celular (TRC) elevado, mesmo quando operados com baixo tempo de detenção hidráulica (TDH). Neste trabalho, investigou-se o desempenho de dois reatores anaeróbios horizontais de leito fixo (RAHLF) em escala de bancada, usados no tratamento do efluente de uma indústria de refrigerantes, sendo um dos reatores preenchido com grânulos e o outro com espuma de poliuretano. A pesquisa foi dividida em três etapas, referentes aos tempos de detenção hidráulica (TDH) de, respectivamente, 20 h, 10 h e 5 h. O encerramento de cada etapa ocorria quando se verificava a estabilidade operacional do sistema através dos parâmetros: DQO, ácidos voláteis totais e pH. Ao final de cada etapa, foram obtidos os perfis de concentração de DQO ao longo dos reatores. Para TDH de 10 h, os valores obtidos para a constante cinética aparente (klapp) foram de 0,694 h-1, para o reator com grânulos, e de 0,467 h-1, para o reator preenchido com espuma de poliuretano. No decorrer da pesquisa, os reatores apresentaram alguns problemas operacionais, que aumentaram à medida em que se reduzia o TDH. Avaliou-se, também, o tempo de residência real do reator com espumas através de experimentos hidrodinâmicos (traçadores). Ao final do experimento, foram quantificados os sólidos voláteis em cada reator e buscou-se diferenciar o arranjo e a fauna microbiológica, presentes nos dois tipos de imobilização, através de microscopia eletrônica de varredura (MEV). / Immobilized biomass reactors have been increasingly used for wastewater treatment due to their capacity of maintaining high cellular retention time (CRT) even when operating at low hydraulic detention time (HDT). In this work, the performances of two horizontal-flow anaerobic immobilized biomass (HAIB) bench-scale reactors treating soft drinks industry effluents were investigated and compared. One of the reactors was filled with granules and the other one with polyurethane foam matrices. The research was conducted in three stages, concerning to hydraulic detention times of, respectively, 20 h, 10 h and 5 h. A stage was considered finished when reactors operational stability was checked by means of COD, total volatile fatty acids and pH. COD profiles were obtained along the reactors at the end of each stage. In the second stage, when HDT was equal to 10 h, the apparent kinetic constant (klapp) values were 0.694 h-1, to the reactor filled with grains, and 0.467 h-1, to the other one. During the research, the reactors showed some operational problems, that increased when the HDT was reduced. The real hydraulic detention time (HDT) reactor with polyurethane foams was evaluated through the hydrodynamic experiments (tracers). Volatile solids of each reactor were quantified at the end of experiment. The arrangement and microbiological fauna inside the reactors were determined by Scanning Electron Microscopy (SEM).
6

Entwicklung einer Technologie zur langzeitstabilen Biologischen Reinigung schwermetallbelasteter Bergbauwässer

Deusner, Christian 04 October 2004 (has links) (PDF)
A new technology for biotechnological treatment of mine waters with both high concentrations of heavy metals and sulphate was developed. The technology is based on the technical coupling of microbially mediated hydrolysis, fermentation and microbial sulphate reduction in a self-stabilising process. Electron donor for sulphate reduction is supplied by degradation of a solid substrate (silage). Elimination of metals is primarily achieved by sulphide precipitation within the sulphate reduction zone. The organic compounds are either supplied by elution or by hydrolysis of polymeric compounds which was named active elution. The concept was realised as a two-phase process with (active) elution in the first phase (R1) and sulphate reduction and metal elimination in the second phase (R2). With this process setup the supply of sufficient amounts of electron donor in R1, a stable and effective sulphate reduction yield as the basis of metal elimination in R2 and a stable separation of microbial processes in R1 and R2 was achieved at hydraulic retention times of 69 h in R1 and 40 h in R2. Almost complete elimination of heavy metals was achieved from wastewaters with 0.2 mM Ni2+, Cu2+, Zn2+, Fe2+ and Mn2. A structurised mathematical model describing the two-phase process was developed on the basis of literature values and tested with data from continuous experiments. Microbial processes were significantly influenced in the presence of precipitated heavy metal sulfides. The effect was dependent on both the bound metal (Ni2+ or Fe2+) and the relative distance between sediment and biomass. / Es wurde eine neuartige Technologie zur biotechnologischen Reinigung von schwermetallbelasteten, sulfathaltigen Bergbauwässern entwickelt. Die Technologie basiert auf der technischen Kopplung von mikrobiell vermittelter Hydrolyse, Fermentation und mikrobieller Sulfatreduktion in einem selbststabilisierenden Prozess, wobei aus Abbau eines festen Substanzgemisches (Silage) Elektronendonor zur Sulfatreduktion bereitgestellt wird. Die Schwermetallelimination erfolgt vorrangig durch sulfidische Fällung, die technisch einstufig mit der mikrobiellen Sulfatreduktion realisiert wurde. Die organischen Verbindungen wurden durch Elution bereitgestellt bzw. durch hydrolytischen Abbau von polymeren Verbindungen. Hierfür wurde der Begriff der ?Aktiven Elution? geprägt. Die Konzeption wurde technisch zweistufig umgesetzt. In der ersten Stufe (R1) erfolgt die (Aktive) Elution, in der zweiten Stufe (R2) erfolgen Sulfatreduktion und Schwermetallelimination. Mit der verfahrenstechnischen Umsetzung wurde die Bereitstellung einer ausreichenden Menge an Elektronendonor in R1, eine effektive und stabile Sulfatreduktionsausbeute als Bedingung der Schwermetallelimination in R2 und eine weitgehende Trennung der mikrobiellen Prozesse in R1 und R2 bei Verweilzeiten von 69 h in R1 und 40 h in R2 erreicht. Bei Behandlung von wässrigen Lösungen mit 0,2 mM Ni2+, Cu2+, Zn2+, Fe2+ und Mn2+ konnte eine nahezu vollständige Elimination der Schwermetalle aus der Lösung erreicht werden. Es wurde ein strukturiertes mathematisches Modell für den zweistufigen Prozess auf der Basis von Literaturangaben entwickelt und anhand der kontinuierlichen Laborversuche überprüft. Es wurde ein erheblicher Einfluss schwermetallsulfidischer Präzipitate auf die mikrobiellen Prozesse festgestellt. Dabei wurde dieser Einfluss in Abhängigkeit von der Art der gebundenen Metallionen (Ni2+ oder/und Fe2+) und in Abhängigkeit der relativen räumlichen Anordnung von Sediment und Biomasse festgestellt.
7

Entwicklung einer Technologie zur langzeitstabilen Biologischen Reinigung schwermetallbelasteter Bergbauwässer

Deusner, Christian 27 May 2004 (has links)
A new technology for biotechnological treatment of mine waters with both high concentrations of heavy metals and sulphate was developed. The technology is based on the technical coupling of microbially mediated hydrolysis, fermentation and microbial sulphate reduction in a self-stabilising process. Electron donor for sulphate reduction is supplied by degradation of a solid substrate (silage). Elimination of metals is primarily achieved by sulphide precipitation within the sulphate reduction zone. The organic compounds are either supplied by elution or by hydrolysis of polymeric compounds which was named active elution. The concept was realised as a two-phase process with (active) elution in the first phase (R1) and sulphate reduction and metal elimination in the second phase (R2). With this process setup the supply of sufficient amounts of electron donor in R1, a stable and effective sulphate reduction yield as the basis of metal elimination in R2 and a stable separation of microbial processes in R1 and R2 was achieved at hydraulic retention times of 69 h in R1 and 40 h in R2. Almost complete elimination of heavy metals was achieved from wastewaters with 0.2 mM Ni2+, Cu2+, Zn2+, Fe2+ and Mn2. A structurised mathematical model describing the two-phase process was developed on the basis of literature values and tested with data from continuous experiments. Microbial processes were significantly influenced in the presence of precipitated heavy metal sulfides. The effect was dependent on both the bound metal (Ni2+ or Fe2+) and the relative distance between sediment and biomass. / Es wurde eine neuartige Technologie zur biotechnologischen Reinigung von schwermetallbelasteten, sulfathaltigen Bergbauwässern entwickelt. Die Technologie basiert auf der technischen Kopplung von mikrobiell vermittelter Hydrolyse, Fermentation und mikrobieller Sulfatreduktion in einem selbststabilisierenden Prozess, wobei aus Abbau eines festen Substanzgemisches (Silage) Elektronendonor zur Sulfatreduktion bereitgestellt wird. Die Schwermetallelimination erfolgt vorrangig durch sulfidische Fällung, die technisch einstufig mit der mikrobiellen Sulfatreduktion realisiert wurde. Die organischen Verbindungen wurden durch Elution bereitgestellt bzw. durch hydrolytischen Abbau von polymeren Verbindungen. Hierfür wurde der Begriff der ?Aktiven Elution? geprägt. Die Konzeption wurde technisch zweistufig umgesetzt. In der ersten Stufe (R1) erfolgt die (Aktive) Elution, in der zweiten Stufe (R2) erfolgen Sulfatreduktion und Schwermetallelimination. Mit der verfahrenstechnischen Umsetzung wurde die Bereitstellung einer ausreichenden Menge an Elektronendonor in R1, eine effektive und stabile Sulfatreduktionsausbeute als Bedingung der Schwermetallelimination in R2 und eine weitgehende Trennung der mikrobiellen Prozesse in R1 und R2 bei Verweilzeiten von 69 h in R1 und 40 h in R2 erreicht. Bei Behandlung von wässrigen Lösungen mit 0,2 mM Ni2+, Cu2+, Zn2+, Fe2+ und Mn2+ konnte eine nahezu vollständige Elimination der Schwermetalle aus der Lösung erreicht werden. Es wurde ein strukturiertes mathematisches Modell für den zweistufigen Prozess auf der Basis von Literaturangaben entwickelt und anhand der kontinuierlichen Laborversuche überprüft. Es wurde ein erheblicher Einfluss schwermetallsulfidischer Präzipitate auf die mikrobiellen Prozesse festgestellt. Dabei wurde dieser Einfluss in Abhängigkeit von der Art der gebundenen Metallionen (Ni2+ oder/und Fe2+) und in Abhängigkeit der relativen räumlichen Anordnung von Sediment und Biomasse festgestellt.

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