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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.
11

Mobil slamavvattning med polymer : Jämförelse av avloppsvattens partikelhalt beroende av tömningsmetod

Ramström, Emma January 2018 (has links)
The purpose of the study was to evaluate which method for emptying of septic tanks that contributed with the lowest particle content in outgoing water during the period of a year. The methods for emptying in the comparison was mobile dewatering using polymer, complete pump-out and mobile dewatering using mechanic separation. Within the study, wastewater was sampled from septic tanks third compartment, however, only from septic tanks that were dewatered using polymer. Samples were taken one time before emptying followed by five occasions after emptying. The results from those samples were compared to previously existing results from complete pump-out and mobile dewatering using mechanic separation. Due to differences in method for sampling, the comparison in the discussion was limited to; samples taken before emptying and two weeks after emptying from septic tanks that had been completely pumped-out and dewatered using mechanic separation. The samples taken before emptying showed the particle content after using the septic tanks for a year since the previous emptying. Based on those samples there were no significant difference between mobile dewatering using polymer and complete pump-out or between mobile dewatering using polymer and mobile dewatering using mechanic separation. Two weeks after emptying the lowest particle contents were found in septic tanks that had been completely pumped-out followed by the two dewatering methods.
12

Enriquecimento de amido de biomassa produzida em lagoa de lemna utilizando a espécie Landoltia punctata / Biomass starch enrichment produced in duckweed pond using the species Landoltia puncta

Smaniotto, Flaviane [UNESP] 16 May 2016 (has links)
Submitted by FLAVIANE SMANIOTTO null (flavi.esa@gmail.com) on 2016-06-09T14:56:47Z No. of bitstreams: 1 Flaviane Smaniotto.pdf: 1913605 bytes, checksum: 1a28a5e684effafd1a52d6186c7e9d6e (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-06-13T16:39:24Z (GMT) No. of bitstreams: 1 smaniotto_f_me_ilha.pdf: 1913605 bytes, checksum: 1a28a5e684effafd1a52d6186c7e9d6e (MD5) / Made available in DSpace on 2016-06-13T16:39:24Z (GMT). No. of bitstreams: 1 smaniotto_f_me_ilha.pdf: 1913605 bytes, checksum: 1a28a5e684effafd1a52d6186c7e9d6e (MD5) Previous issue date: 2016-05-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A busca de alternativas para melhorar a qualidade dos efluentes de estações de tratamento de esgotos domésticos lançados corpos d´água, aliado a busca de alternativas econômicas e de baixo custo que o uso de macrófitas aquáticas da subfamília Lemnaceae, e o seu potencial de despoluição de águas contaminadas, atuando principalmente na remoção de nutrientes, como nitrogênio e fósforo relacionados a processo de eutrofização. Visando dar destino a biomassa de lemna produzida, este trabalho tem o objetivo de avaliar sua composição química, a produção de biomassa, e quantificar o amido e a proteína bruta acumulada. Ao avaliar seu crescimento obtido em tanques em escala piloto, cultivadas em efluente de lagoa de estabilização o crescimento relativo alcançado com 12 dias de cultivo foi de 5,29g/m²dia, o que equivale a 19,3 t/ha.ano matéria seca. O amido contido no período de crescimento foi de 3,2±0,9%, e no enriquecimento 4,7±1,5% de amido, o equivalente a 0,61t/ha.ano de amido disponível e a quantidade de proteína bruta disponível equivale a 8,07t/ha.ano. Esta biomassa pode ser utilizada para diversos fins, como para o preparo de rações animais devidos sua alta quantidade de proteína bruta, ou a produção de etanol devido sua quantidade de amido e hemicelulose. / The search for alternatives to improve the quality of domestic effluents emitted into water bodies, coupled with the search for economic alternatives and cost that the use of aquatic weeds of Lemnaceae subfamily, and its potential for contaminated water pollution, mainly in removal of nutrients such as nitrogen and phosphorus related to eutrophication. Aiming to target biomass duckweed produced, this study aims to evaluate their chemical composition, biomass, and quantify starch and crude protein accumulated. When evaluating growth achieved in tanks on a pilot scale, grown in stabilization pond effluent relative growth reached 12 days of cultivation was 5,29g/m²day, equivalent to 19.3t/ha.year dry matter. The starch in the growth period was 3.2 ± 0.9% and 4.7 ± 1.5% enrichment starch, equivalent to 0,61t / ha.year available starch and the amount of protein gross available equals 8,07t / ha year. This biomass can be used for various purposes such as for the preparation of animal feeds due to their high amount of crude protein, or the production of ethanol because its amount of starch and hemicellulose.
13

Avaliação quantitativa de riscos microbiológicos (AQRM) associados à E. coli em águas cinza

Pasin, Débora Brunheroto [UNESP] 01 August 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:29:31Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-08-01Bitstream added on 2014-06-13T19:59:10Z : No. of bitstreams: 1 pasin_db_me_bauru.pdf: 597021 bytes, checksum: 186b1dd9901aafb4d694462951b7f7c7 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O reúso de águas cinza apresenta-se como uma alternativa de ampliação da oferta de água que pode contribuir para a conservação dos recursos híbridos, perante a escassez da água, não apenas pela qualidade, mas também pela quantidade. Os riscos associados à exposição rotineira ou acidental dessa fonte de alternativa devem, entretanto, ser considerados, para que se possam estabelecer práticas seguras de reúso, uma vez que as águas de reúso podem apresentar patógenos, tais como: vírus, bactérias, protozoários e helmintos. O presente trabalho teve como objetivo avaliar quantitativamente os riscos microbiológicos das diversas fontes de exposições dos usuários a E. coli na água cinza sem tratamento, a fim de definir uma faixa de Valores Máximos Permitidos (VMP) por meio de conceito de riscos aceitáveis 10-3 e 10-6 pppa (por pessoa por ano), para as diversas finalidades de reúso. Para tal, foram avaliadas a exposição, a dose-resposta e a probabilidade de infecção para diferentes finalidades de reúso. O modelo de beta-Poisson foi empregado para avaliação da probabilidade de infecção. A dose infectante (N50), a concentração de microorganismos, a rota de exposição, os volumes ingeridos (acidentalmente e rotineiramente), os parâmetros de interação agente-hospedeiro (α e β), bem como a frequencia de exposição foram avaliados a partir de uma compilação sistemática de dados da literatura. E, por meio da Avaliação Quantitativa de Riscos Microbiológicos (AQRM), o maior risco de infecção identificado decorreu do reúso de águas cinza misturadas para a finalidade de balnearidade e irrigação de culturas alimentares por meio de ingestão de alimentos, incorrendo em risco de aproximadamente 9,9 pessoas de cada dez indivíduos expostos, sem considerar os efeitos de diluição da água. Esse cenário, resultou... / The reuse of greywater is presented as an alternative to increasing the supply of water that can contribute to the conservation of water resources against water scarcity, not only the quality but also the quantity. The risks associated with exposure routine or accidental this alternative source should, however, be considered, so that they establish safe practices of reuse, since reusing water may have pathogens, such as viruses, bacteria, protozoa and helminths. The present study aimed to quantitatively evaluate the microbiological risks of different sources of exposure of users to E. coli in untreated gray water, in order to define a range of Maximum Values Allowed (MVA) through the concept of acceptable risk 10-3 and 10-6 pppy (per person per year), for the various purposes of reuse. To this end, we evaluated the exposure, the dose -response and the probability of infection for different purpose reuse. The beta-Poisson model was used to assess the likehood of infection. The infective dose (N50), the concentration of microorganisms, the route of exposure, the volumes ingested (accidentally and roubinely), the parameters of agent-host interaction (α and β), and the frequency of exposure were evaluated from one systematic compilation of literature. And, through Quantitative Microbiological Risk Assessment (QMRA), the greatest risk of infection identified resulted from the reuse of greywater mixed for the purpose of bathing and irrigation of food crops through food intake, resulting in risk of approximately 9,9 out of ten people exposed individuals, without considering the effects dilution water. This situation has resulted in MVA 5.25 to 105 MPN/100 mL and 3.95 to 39.5 MPN/100 mL, respectively, to an acceptable risk of 10-3 ppy and 0.00 to 0.10 MPN/100 mL and 0.00 to 0.04 MPN/100mL simultaneously to risk of 10-6 pppy. The lowest risk of infection was due... (Complete abstract click electronic access below)
14

Enriquecimento de amido de biomassa produzida em lagoa de lemna utilizando a espécie Landoltia punctata /

Smaniotto, Flaviane January 2016 (has links)
Orientador: Liliane Lazzari Albertin / Resumo: A busca de alternativas para melhorar a qualidade dos efluentes de estações de tratamento de esgotos domésticos lançados corpos d´água, aliado a busca de alternativas econômicas e de baixo custo que o uso de macrófitas aquáticas da subfamília Lemnaceae, e o seu potencial de despoluição de águas contaminadas, atuando principalmente na remoção de nutrientes, como nitrogênio e fósforo relacionados a processo de eutrofização. Visando dar destino a biomassa de lemna produzida, este trabalho tem o objetivo de avaliar sua composição química, a produção de biomassa, e quantificar o amido e a proteína bruta acumulada. Ao avaliar seu crescimento obtido em tanques em escala piloto, cultivadas em efluente de lagoa de estabilização o crescimento relativo alcançado com 12 dias de cultivo foi de 5,29g/m²dia, o que equivale a 19,3 t/ha.ano matéria seca. O amido contido no período de crescimento foi de 3,2±0,9%, e no enriquecimento 4,7±1,5% de amido, o equivalente a 0,61t/ha.ano de amido disponível e a quantidade de proteína bruta disponível equivale a 8,07t/ha.ano. Esta biomassa pode ser utilizada para diversos fins, como para o preparo de rações animais devidos sua alta quantidade de proteína bruta, ou a produção de etanol devido sua quantidade de amido e hemicelulose. / Abstract: The search for alternatives to improve the quality of domestic effluents emitted into water bodies, coupled with the search for economic alternatives and cost that the use of aquatic weeds of Lemnaceae subfamily, and its potential for contaminated water pollution, mainly in removal of nutrients such as nitrogen and phosphorus related to eutrophication. Aiming to target biomass duckweed produced, this study aims to evaluate their chemical composition, biomass, and quantify starch and crude protein accumulated. When evaluating growth achieved in tanks on a pilot scale, grown in stabilization pond effluent relative growth reached 12 days of cultivation was 5,29g/m²day, equivalent to 19.3t/ha.year dry matter. The starch in the growth period was 3.2 ± 0.9% and 4.7 ± 1.5% enrichment starch, equivalent to 0,61t / ha.year available starch and the amount of protein gross available equals 8,07t / ha year. This biomass can be used for various purposes such as for the preparation of animal feeds due to their high amount of crude protein, or the production of ethanol because its amount of starch and hemicellulose. / Mestre
15

Emissão de metano nas lagoas de decantação da Estação de tratamento de esgotos de Jundiaí / Methane emission from decantation lagoons in Jundiaí wastewater treatment plant

Santos, Antonio Carlos dos 16 August 2018 (has links)
Orientadores: Edson Aparecido Abdul Nour, Pedro Sérgio Fadini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-16T21:36:15Z (GMT). No. of bitstreams: 1 Santos_AntonioCarlosdos_M.pdf: 4339309 bytes, checksum: 8c2a2b650382806186dfd588a5c69deb (MD5) Previous issue date: 2010 / Resumo: No presente trabalho foi verificada a contribuição nas emissões de metano para a atmosfera da Estação de Tratamento de Esgoto de Jundiaí, em duas campanhas de coletas em suas lagoas de decantação, com as amostragens sendo realizadas em pontos próximos à entrada e à saída das lagoas. Utilizou-se um coletor de gás semelhante ao concentrador de gás interno do reator UASB, a técnica da câmara estática para amostragem dos fluxos totais e a câmara estática adaptada para a coleta dos fluxos difusivos, na qual foi instalado um anteparo para impedir a coleta dos fluxos ebulitivos. Para a análise dos fluxos foram medidas as variáveis ambientais, pressão e temperatura. Os fluxos foram medidos e divididos por tipo: difusivos (liberados para a atmosfera por meio da difusão mássica) e ebulitivos (liberados para a atmosfera por meio de bolhas). O fluxo ebulitivo representou cerca de 95% da liberação total de metano para a atmosfera, e um valor médio de 9.008 mg CH4/m2 d. O fluxo difusivo teve valor médio de 421 mg CH4/m2 d. Devido a pouca variação nas temperaturas não foi possível verificar a sua correlação com os fluxos de metano. Porém com a altura do manto de lodo no interior das lagoas a correlação foi direta. Na estimativa do potencial energético do metano, os 471 kg CH4/d que poderiam ser recuperados, gerariam até 196 MWh/mês de energia elétrica, desconsiderando-se as perdas do sistema. Considerando-se o fluxo total médio e a área total das quatro lagoas de decantação, a emissão anual de metano foi de 264 Mg CH4. Estas estimativas ainda conservam uma incerteza devido às extrapolações das medidas realizadas / Abstract: In the present work was estimated the contribution of methane emission to the global atmosphere. In this study were realized two campaigns of collections in the settling ponds n.°03 (2008) and n.°04 (2010) with sampling operation being carried out in points coming into and out of the lagoons. A gas collector has been utilized as the UASB inner gas keeper and the static chamber technique to samples of the total flux, that chamber was adapted to collect diffusive flux in which was settled a screen to prevent bubble flux. To the flux analyses were measured some environmental variable mainly the temperature, and divided by type: diffusive (released to the atmosphere through the massive diffusion) and bubble (released to the atmosphere through bubble). The bubble flux submitted about 95% of the total methane liberation to the atmosphere and submitted an average value of 9.008 mgCH4/m².day. The diffusive flux submitted an average value of 421 mgCH4/m².day. Due of a little variation in the temperature it was not possible to verify the co-relation between methane flux with the temperatures. In spite of the height backlog of sludge in the deep of collection the direct co-relation was obtained. In the energetic potential of methane was estimated 471 kgCH4/day that could be recovered, would generate until 196 MWh/month of energy ignoring the system loss. Considering the average total flux of total area of the collection decantation lagoons, the annual emission of methane was 264 MgCH4 (Mega grams of methane). Those estimates still retain an uncertainty due extrapolations of the measures carried out / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
16

Seleção de microalgas dos gêneros Desmodesmus e Scenedesmus produtoras de lipídeos: otimização do cultivo e aplicação do efluente doméstico de reator UASB como substrato alternativo à produção de biodiesel / Selection of lipid-bearing microalgae of the genus Desmodesmus and Scenedesmus: culture optimization and application of domestic wastewater from UASB reactor as an alternative substrate for the production of biodiesel

Raquel Andrade de Rossi 01 November 2013 (has links)
Microalgas são interessantes fontes de lipídeos para produção de biodiesel. No entanto, seus cultivos para tal finalidade são apenas viáveis do ponto de vista ambiental e econômico se apresentarem elevadas produtividades de biomassa e de lipídeos e estiverem associados ao uso de efluentes. A presente pesquisa estudou as condições de cultivo das microalgas Desmodesmus e Scenedesmus, considerando o conteúdo lipídico para produção de biodiesel, aliado à análise da eficiência de remoção de nutrientes pelas cepas, além da avaliação do efluente de reator UASB (esgoto sanitário) como meio alternativo ao cultivo. Dentre 22 cepas de microalgas isoladas de ambientes de água doce e lagoas de estabilização, 2 foram selecionadas para otimização de seus cultivos diante das suas capacidades de acumularem lipídeos e crescerem em diferentes condições físico-químicas. Delineamento Composto Central Rotacional (DCCR) foi aplicado para otimização das condições de crescimento celular das cepas LE17 (34,5ºC, pH 8,2 e 200 &#956mol.m-2.s-1) e ITU07 (34ºC, pH 8,2 e 180 &#956mol.m-2.s-1). Definidas as condições ótimas, foram realizados os cultivos mixotróficos das cepas em batelada (8 litros) em meio sintético e em efluente de reator UASB (50%). Nos cultivos em efluente de reator UASB as produtividades de biomassa das cepas LE17 e ITU07 foram, respectivamente, 3,4 e 3 vezes maiores do que as obtidas na condição não otimizada (controle) o que demonstrou a viabilidade do esgoto sanitário como meio alternativo ao cultivo de microalgas. Nos cultivos em meio sintético as produtividades de biomassa das cepas LE17 e ITU07 foram, respectivamente, 48,3 e 22,6 vezes maiores do que as observadas na condição não otimizada (controle). Os conteúdos lipídicos das cepas sob condição otimizada (em meio sintético e no efluente do reator) apresentaram aumento (1%-6,1%) em relação aos observados na condição controle. Assim, houve elevação das produtividades de biomassa das cepas e por consequência, aumento da produção de lipídeos. Os principais ácidos graxos identificados nos lipídeos extraídos foram C16:0 e C18:1. O estudo da remoção de nutrientes pelas microalgas verificou que as cepas são eficientes na remoção de nitrogênio e fósforo tanto do meio sintético quanto do efluente do reator UASB. / Microalgae are interesting source of lipids for biodiesel production. However, their cultivation for this purpose is only economic and environmental feasible if high biomass and lipid productivity are achieved under wastewater use as nutrients source. This research aimed to improve the culture conditions of Chlorococcales microalgae (Desmodesmus and Scenedesmus), considering the lipid content for biodiesel production, the efficiency of nutrient removal by strains, besides the evaluation of wastewater from UASB reactor as an alternative substrate for the cultures. Among 22 strains of microalgae isolated from freshwater environments and stabilization ponds, 2 were selected for culture optimization due to their capacity of accumulating lipids and growing under different physicochemical conditions. Central Composite Design (CCD) was applied to optimization of cell growth conditions of strains LE17 (34,5ºC, pH 8,2 e 200 &#956mol.m-2.s-1) and ITU07 (34ºC, pH 8,2 e 180 &#956mol.m-2.s-1). The optimal conditions were defined and mixotrophic batch cultivations (8 liters) of strains in synthetic medium and in wastewater from UASB reactor (50%) were performed. The biomass productivities of the strains LE17 and ITU07 in domestic wastewater cultivation were, respectively, 3,4 e 3,0 times higher than those obtained in the non-optimized condition (control). This suggested the feasibility of wastewater use as an alternative substrate for the microalgae cultivation. The biomass productivities of the strains LE17 and ITU07 in synthetic medium cultivation were, respectively, 48,3 e 22,6 times higher than those observed in non-optimized condition (control). The lipid content of strains under optimized conditions (in synthetic medium and domestic wastewater) showed an increase (1%-6,1%) compared to those observed in the control condition. Thus, there was an increase in biomass productivities of the strains and consequently, increased production of lipids. The major fatty acids identified in the extracted lipids were C16:0 e C18:1. The study of nutrients removal by microalgae found that the strains are efficient in the uptake of nitrogen and phosphorus from both the synthetic medium and wastewater from the UASB reactor.
17

Pós-tratamento de efluente de reator anaeróbio em sistema seqüencial constituído de ozonização em processo biológico aeróbio / Upflow anaerobic sludge blanket reactor effluent of post-treatment using oxidation with ozone and submerged aerated biofilter

Ana Beatriz Barbosa Vinci Lima 22 September 2006 (has links)
O pós-tratamento apresenta-se como uma forma de adequar o efluente de reatores anaeróbios aos requisitos da legislação ambiental e propiciar a proteção dos corpos receptores. O trabalho foi desenvolvido com a finalidade de avaliar a viabilidade técnica da utilização do processo de ozonização quando aplicado a um sistema combinado composto por reator UASB seguido por biofiltro aerado submerso. No sistema foi avaliada a operação de quatro biofiltros, dois com carvão ativado e dois com anéis de polietileno. Para verificar a influência da oxidação com ozônio na biodegrabilidade somente um dos biofiltros preenchidos por cada material suporte recebeu efluente ozonizado. Os menores valores de concentração de DQO foram encontrados nos filtros preenchidos com carvão ativado granular, com valores de até 14,00 mg/L, para os dois tipos de afluentes, ozonizado e não-ozonizado. Contudo, considerando eficiência de remoção de DQO para todo período de operação os biofiltros preenchidos com anéis de polietileno se mostraram mais eficazes, com eficiência de até 80%. Os resultados evidenciaram a ocorrência de nitrificação em todos os sistemas, uma vez que houve consumo de NTK e de alcalinidade, com queda de pH; produção de nitrato. / The post-treatment is presented as an alternative to adjust the effluent of anaerobic reactors to the requirements of the brazilian environmental legislation. The work was developed with the purpose to evaluate the viability of the use of the ozonization process when applied to a system composed by a reactor UASB followed by submerged aerated biofilter. In the system the operation of four biofilters was evaluated, two fillet with granular activated carbon (GAC) and two with polyethylene rings. To check the influence of the oxidation with ozone in biodegradability, only one of the biofilter with each support material received ozonized effluent. The lowest values of DQO concentration had been found in the filters with GAC, with values of up to 14,00 mg/L, for the two types, ozonized and not-ozonized. However, considering the DQO removal efficiency for all operation periods the biofilters with polyethylene rings were more efficient, with efficiency of up to 80%. The results had evidenced the occurrence of nitrification in all the systems, a time that had NTK and alkalinity consumption, with fall of pH and nitrate production.
18

Optimising the use of small-scale greywater treatment plants in South Africa

Natha, Shaym 26 June 2015 (has links)
M.Ing. (Civil Engineering) / To relieve the extreme pressure placed on overburdened water and wastewater infrastructure, the reuse of light wastewater was identified as a possible source of water supply for non-potable applications. The light wastewater discharge intercepted on-site can be recycled, treated and thereafter distributed to fixtures for agricultural, sanitation and gardening based activities. Sources for this light wastewater stream includes bathroom showers, bath tubs, hand wash basins including that of kitchens, laundry and washing machine outflows of recyclable quality. This type of re-usable water is called greywater (GW). This on-site re-use concept has potential to offer greater potable water savings if correctly implemented. For the purpose of this research, this particular type of waste stream excluding the kitchen and laundry discharge was the water source considered for the supply to this greywater treatment plant (GWTP). In 2009, the Water Research Commission (WRC) funded a greywater pilot study in a joint venture between the University of Witwatersrand (WITS) and the University of Johannesburg (UJ). Over the last few years, this project had progressed with new outcomes each year. The pilot GWTP at Unit 51, Student Town, UJ in Auckland Park was used for the purpose of this study. The selected reuse application for the GW effluent was for toilet flushing. GW was supplied to two toilets in a residential student complex housing 16 female and male students i.e. 8 students on each floor. The highlights of the WRC study included: a lack of satisfactory treatment efficiency and a well-defined protocol to address the problems associated with the slightly poor quality of effluent produced (i.e. unpleasant odours, greyish appearance and the unacceptable microbial count). Determining and addressing the user perceptions and user education about GW usage, respectfully, was a significant component in the successful management of the project. In this report, a practical evaluation of three crucial components of the GWTP was completed. These three components viz. treatment efficiency, user perceptions and quality standards, were common aspects of concern for existing decentralised GWTP’s within residential or small commercial stands.
19

Phosphorus Removal from Domestic Wastewater Using Dual Reactive Materials Polonite® and Absol®.

Fatehi Pouladi, Soheil January 2011 (has links)
Private wastewater treatment facilities release tons of phosphorus to the aquatic environment due to the insufficient removal efficiency in conventional soil infiltration systems. Reactive filter materials have demonstrated promising P removal rates. Laboratory-scale column experiments were carried out using Absol® and Polonite® in dual infiltration media and results were compared with Polonite® functioning as the only layer of reactive filter material. Two sets of experiments were arranged with layer lengths of 5 cm and 15 cm which were operated for 50 and 119 days respectively. Columns with an additional layer of Absol® demonstrated very good average removal rates of 85.99 % and 99.13 % in both experiments while the effluent in the former exceeded the maximum allowed P concentration shortly after half of the total time of the experiment. On the other hand, O-P concentration in collected samples from dual filter media with 15 cm layers of Absol® and Polonite® (column B1) was as low as 0.04 mg/l after 119 days of operation exhibiting high potentials for Absol® in local wastewater treatment. Levels of pH in treated samples showed a decreasing trend in all columns which was similarly simultaneous with high removal rates observed in B1.
20

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.

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