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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.
51

Avaliação dos efeitos do recebimento do lodo de estação de tratamento de água em sistema de tratamento de esgoto pelo processo de lodo ativado com aeração prolongada. / Evaluation of the effects of accepting water treatment plant residual at a wastewater system using prolongated aeration activated-sludge process.

Asada, Lucia Naomi 25 May 2007 (has links)
Nesta pesquisa o principal objetivo foi estudar a influência da disposição de lodo gerado em estação de tratamento de água (ETA), que utiliza sulfato de alumínio como coagulante, nos processos biológicos de tratamento de esgoto por lodo ativado com aeração prolongada. Para isso, uma estação piloto de fluxo contínuo foi operada com idade do lodo de 25 dias em duas condições: inicialmente alimentada somente com esgoto bruto e posteriormente com adição de lodo de ETA à base de alumínio de modo a haver acréscimo nos sólidos em suspensão (SS) do esgoto em 25, 50 e 100 mg/L. Os resultados obtidos mostraram que a principal conseqüência foi o aumento na produção de sólidos do sistema (acréscimos médios de 4,6% com 25 mg/L, 37,7% com 50 mg/L e 41,0% com 100 mg/L) e, portanto, na concentração média de SS no tanque de aeração, no decantador secundário e no lodo produzido em excesso. Como o decantador secundário operou com taxa de aplicação de sólidos abaixo da taxa limite não houve problema de arraste de sólidos pelo efluente final. Não houve interferências na remoção de DBO5,20 (eficiência de remoção acima de 94%). O teste de consumo de oxigênio específico (TCOa/SSV) e o exame microscópico do lodo não apontaram possíveis efeitos tóxicos desse lodo à microfauna existente. Não houve inibição no processo de nitrificação (eficiência média de remoção de nitrogênio Kjeldhal Total e de nitrogênio amoniacal acima de 95%). Houve aumento na concentração de DQO e de SS no efluente final pela própria contribuição do lodo da ETA sobre esses parâmetros. A remoção de fósforo foi observada apenas na forma solúvel com dosagem de 25 mg/L e 50 mg/L (eficiências de remoção de 9,1% e de 21,9% respectivamente). Esses resultados apontam que a disposição do lodo de ETA a base de alumínio em sistema de lodo ativado pode ser realizada sem interferências negativas sobre esses processos biológicos aeróbios. / The main purpose of this research was to study the influence of an alum-coagulated water treatment plant (WTP) sludge on the biological processes of wastewater treatment using extended aeration activated-sludge process. For this, a continuousflow activated-sludge pilot plant was operated at solids retention time (SRT) value of 25 day under two conditions: initially, it was feeded only with sewage and next dosed with alum sludge in way to have an addition about 25, 50 and 100 mg of suspended solids (SS) per liter of incoming sewage. The results showed that the main consequence was the increase of solids production (average addition of 4,6% at 25 mg/L, 37,7% at 50 mg/L and 41% at 100 mg/L dosages) and therefore an increasing of average concentration of SS in aeration tank, secondary clarifier and wasteactivated sludge. As the secondary clarifier operated under solids loading rate limit no solids were discharged in the clarifier effluent. There was no interference on BOD5 removal (removal efficiency above 94%). The specific oxygen uptake rate (SOUR) and the microscopic observations did not show any possible toxic effects to the microbial population inhabiting the activated sludge system. There was no inhibition in nitrification process (average efficiency of Total Kjeldahl nitrogen and ammonia nitrogen removal above 95%). There was an increase of COD and SS in final effluent due to contribution of WTP residuals on these parameters. Phosphorus removal was observed only in soluble form with doses of 25 mg/L and 50 mg/L (removal efficiency of 9,1% and 21,9% respectively). These results indicate that disposal of WTP alum sludge in activated-sludge system can be done without any adverse effects on these aerobic biological processes.
52

Análise de eficiência de biopolímero como composto coadjuvante no processo de coagulação-floculação e sedimentação / Biopolymer efficiency analysis as a coadjuvant compound in the coagulation-flocculation and sedimentation process

Andrade, Erik de Lima [UNESP] 09 February 2017 (has links)
Submitted by Erik de Lima Andrade null (erik_andrade88@hotmail.com) on 2017-03-06T18:12:25Z No. of bitstreams: 1 Dissertação_Erik de Lima Andrade.pdf: 2096082 bytes, checksum: fdfbde2d75d685f0c1cda5fc47b0b3f1 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2017-03-10T14:43:15Z (GMT) No. of bitstreams: 1 andrade_el_me_soro.pdf: 2096082 bytes, checksum: fdfbde2d75d685f0c1cda5fc47b0b3f1 (MD5) / Made available in DSpace on 2017-03-10T14:43:15Z (GMT). No. of bitstreams: 1 andrade_el_me_soro.pdf: 2096082 bytes, checksum: fdfbde2d75d685f0c1cda5fc47b0b3f1 (MD5) Previous issue date: 2017-02-09 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A adequação no tratamento da água, para abastecimento público envolve a compreensão da vulnerabilidade de mananciais e de situações de risco à saúde humana. Da mesma forma, o sucesso do tratamento de água de superfície depende, fortemente, da eficácia do desempenho do coagulante. Com a qualidade dos mananciais comprometida por diferentes cenários, tornase indispensável, o processo de desenvolvimento de abordagens eficazes para as questões de caráter econômico e ambiental. O tratamento de água de superfície objetiva, de modo geral, a remoção de impurezas com o propósito de enquadrá-la no padrão de potabilidade, essencialmente, através do uso de produtos químicos. Neste sentido, o presente trabalho analisou a eficiência de três produtos comerciais: sulfato de alumínio, policloreto de alumínio e PGα21Ca. Para tanto, foram realizados ensaios de coagulação-floculação e sedimentação, em água da ETA de Salto de Pirapora, São Paulo, Brasil. Os resultados obtidos do PGα21Ca revelam caráter, essencialmente, inorgânico, com teores elevados de sulfato de cálcio (87%) e 5% de ácido γ-poliglutâmico, entre outros compostos químicos. O PGα21Ca apresentou maior eficiência de remoção de turbidez e cor aparente, com valores de 1,93 NTU de turbidez remanescente e 96,89% de remoção de cor aparente e pouca alteração no pH do meio, demonstrando efetividade para o tratamento de água para abastecimento público. O PAC apresentou resultados inferiores para clarificação da água quando comparado ao PGα21Ca e melhores resultados quando comparado ao sulfato de alumínio. Utilizando-se o PGα21Ca em água de Rio Grande, não obtém-se resultados tão expressivos quando comparado a água da ETA de Salto de Pirapora. / The suitability in the treatment of water for public supply involves understanding the vulnerability of sources and situations of risk to human health. Similarly, the success of surface water treatment depends strongly on the effectiveness of the coagulant performance. With the quality of water sources compromised by different scenarios, it is essential to the effective approaches development process for the economic and environmental character issues. The water treatment lens surface generally the removal of impurities in order to fit it in potable standard, mainly through the use of chemicals. In this sense, the present study examined the effectiveness of three commercial products: aluminum sulphate, polyaluminum chloride and PGα21Ca. Therefore, tests were carried out coagulation-flocculation and sedimentation in water of Salto de Pirapora WTP, São Paulo, Brazil. The results obtained reveal the character PGα21Ca essentially inorganic, with high levels of calcium sulfate (87%) and 5% γ-polyglutamic acid, and other chemical compounds. The PGα21Ca showed higher turbidity and apparent color removal efficiency, with values of 1.93 NTU turbidity and remaining 96.89% removal of apparent color and little change in pH of the medium, demonstrating the effectiveness for water treatment. The PAC presented lower results for clarification of water when compared to PGα21Ca and better results when compared to aluminum sulfate. Using PGα21Ca in Rio Grande water did not obtain significant results when compared to the water of the Salto de Pirapora WTP. / FAPESP: 2015/02650-8
53

Ekonomické hodnocení ozdravného protiradonového opatření u rodinných domů / Economic valuation of radon mitigation countermeasures applied in family houses

Černý, Petr January 2010 (has links)
The aim of the thesis is to valuate economic effectivity of radon mitigation countermeasures co-financed by the state applied in family houses which display high radon level. Feasibility of the mitigation is analysed without concering financing source. Furthermore, the project is valuated from the point of view of the house owner and from the state's point of view. Presence of residental radon is increasing lung cancer probability, radon has notable healt effects. Costs and benefit of the hypothetic project are vauated in CBA analysis. The author finds the project unfeasible. CBA is discussed as a suitable economic tool for fiding alternative technological method aiming to social effectivity. Providing feasible change of remediation parametres caused positive social value of the project, socioeconomic flow in the state point of view would remain negative. Therefore, state participation on the radon mitigation countermeasures of private family houses is not reccomended.
54

Avaliação dos efeitos do recebimento do lodo de estação de tratamento de água em sistema de tratamento de esgoto pelo processo de lodo ativado com aeração prolongada. / Evaluation of the effects of accepting water treatment plant residual at a wastewater system using prolongated aeration activated-sludge process.

Lucia Naomi Asada 25 May 2007 (has links)
Nesta pesquisa o principal objetivo foi estudar a influência da disposição de lodo gerado em estação de tratamento de água (ETA), que utiliza sulfato de alumínio como coagulante, nos processos biológicos de tratamento de esgoto por lodo ativado com aeração prolongada. Para isso, uma estação piloto de fluxo contínuo foi operada com idade do lodo de 25 dias em duas condições: inicialmente alimentada somente com esgoto bruto e posteriormente com adição de lodo de ETA à base de alumínio de modo a haver acréscimo nos sólidos em suspensão (SS) do esgoto em 25, 50 e 100 mg/L. Os resultados obtidos mostraram que a principal conseqüência foi o aumento na produção de sólidos do sistema (acréscimos médios de 4,6% com 25 mg/L, 37,7% com 50 mg/L e 41,0% com 100 mg/L) e, portanto, na concentração média de SS no tanque de aeração, no decantador secundário e no lodo produzido em excesso. Como o decantador secundário operou com taxa de aplicação de sólidos abaixo da taxa limite não houve problema de arraste de sólidos pelo efluente final. Não houve interferências na remoção de DBO5,20 (eficiência de remoção acima de 94%). O teste de consumo de oxigênio específico (TCOa/SSV) e o exame microscópico do lodo não apontaram possíveis efeitos tóxicos desse lodo à microfauna existente. Não houve inibição no processo de nitrificação (eficiência média de remoção de nitrogênio Kjeldhal Total e de nitrogênio amoniacal acima de 95%). Houve aumento na concentração de DQO e de SS no efluente final pela própria contribuição do lodo da ETA sobre esses parâmetros. A remoção de fósforo foi observada apenas na forma solúvel com dosagem de 25 mg/L e 50 mg/L (eficiências de remoção de 9,1% e de 21,9% respectivamente). Esses resultados apontam que a disposição do lodo de ETA a base de alumínio em sistema de lodo ativado pode ser realizada sem interferências negativas sobre esses processos biológicos aeróbios. / The main purpose of this research was to study the influence of an alum-coagulated water treatment plant (WTP) sludge on the biological processes of wastewater treatment using extended aeration activated-sludge process. For this, a continuousflow activated-sludge pilot plant was operated at solids retention time (SRT) value of 25 day under two conditions: initially, it was feeded only with sewage and next dosed with alum sludge in way to have an addition about 25, 50 and 100 mg of suspended solids (SS) per liter of incoming sewage. The results showed that the main consequence was the increase of solids production (average addition of 4,6% at 25 mg/L, 37,7% at 50 mg/L and 41% at 100 mg/L dosages) and therefore an increasing of average concentration of SS in aeration tank, secondary clarifier and wasteactivated sludge. As the secondary clarifier operated under solids loading rate limit no solids were discharged in the clarifier effluent. There was no interference on BOD5 removal (removal efficiency above 94%). The specific oxygen uptake rate (SOUR) and the microscopic observations did not show any possible toxic effects to the microbial population inhabiting the activated sludge system. There was no inhibition in nitrification process (average efficiency of Total Kjeldahl nitrogen and ammonia nitrogen removal above 95%). There was an increase of COD and SS in final effluent due to contribution of WTP residuals on these parameters. Phosphorus removal was observed only in soluble form with doses of 25 mg/L and 50 mg/L (removal efficiency of 9,1% and 21,9% respectively). These results indicate that disposal of WTP alum sludge in activated-sludge system can be done without any adverse effects on these aerobic biological processes.
55

Mécanismes de Marché et Évaluation des Biens Publics Environnementaux

Dragicevic, Arnaud 04 December 2009 (has links) (PDF)
Nous abordons dans un premier chapitre la question de l'équivalence entre le CAP et le CAR. La disparité entre les deux indices a de profondes conséquences sur les prises de décision environnementales. Si la disparité était au départ associée aux carences de la méthode de mise en œuvre des enquêtes, les racines du problème s'avèrent être sensiblement plus profondes. Eu égard à l'évaluation des biens publics, nous pensons que la disparité est due à la substituabilité imparfaite entre les biens privés et publiques, ainsi qu'en raison de perceptions différenciées des agents économiques entre gains et pertes. C'est à cette problématique que le premier chapitre se consacre. Ainsi, le Chapitre 1 traite de la disparité entre les indices CAP et CAR dans l'évaluation hors-marché. Dans la littérature, l'effet de substitution et l'effet de dotation sont tenus responsables de l'existence des disparités. Nous montrons que la substituabilité imparfaite dans la fonction d'utilité indirecte peut provoquer la disparité soit entre le CAP et le CAR - en raison du coût d'opportunité -, soit entre les gains et les pertes, où il s'agit d'évaluer une perte sèche. La mesure en termes relatifs accentue la substituabilité imparfaite, mais l'effet de substitution est borné dans le modèle d'aversion aux pertes. Ce premier chapitre prépare le terrain pour le Chapitre 2, où nous évaluons un vrai bien public dans un contexte d'enchères expérimentales. Les offres d'achat et de vente reflètent le CAP et le CAR, d'où leur importance. L'effet de dotation et le choix du meilleur mécanisme d'enchères y sont examinés. Les études en enchères expérimentales jusqu'ici menées ont porté sur des biens privés non marchands ; elles sont supposées divulguer ce qui se passerait en présence de biens publics, car il est a priori difficile d'envisager une expérience où le bien public est échangé. Nous y parvenons. Nous n'employons pas de valeurs induites mais laissons libre cours aux valeurs autoproduites par les sujets d'étude recrutés pour l'occasion. L'étude nous permet de vérifier si, sur des marchés simulés, bien privé non marchand et bien public sont évalués de manière identique. Ainsi, nous évaluons l'impact de trois mécanismes d'enchère - le mécanisme Becker-DeGroot-Marschak (BDM), l'enchère au deuxième prix, et l'enchère aléatoire au nième prix - dans l'évaluation des CAP et CAR privés d'un bien public pur. Nos résultats montrent que l'effet de dotation peut être éliminé en répétant le mécanisme BDM. Néanmoins, à l'échelle logarithmique, l'enchère aléatoire au nième prix donne la vitesse de convergence vers l'égalité des indices de bien-être la plus élevée. Plus généralement, nous observons que les sujets d'étude évaluent les biens publics en se référant à l'avantage privé et subjectif qui résulte du financement du bien public. Par la suite, le Chapitre 3 discute de la sincérité des préférences en enchères expérimentales répétées et traite des propriétés incitatives des mécanismes BDM et l'enchère aléatoire au nième prix. Une propriété des mécanismes d'enchères est la compatibilité avec les incitations, dans laquelle un offreur a une stratégie faiblement dominante de soumettre une offre égale à sa valeur. Il a été prouvé que les deux mécanismes sont compatibles avec les incitations. En évaluation, on répète des sessions d'enchères pour donner aux offreurs l'opportunité d'apprendre le mécanisme de marché : leur donner du temps pour révéler leurs préférences. Or, ce procédé les contre-incite à adapter leurs préférences en fonction des prix publiquement signalés, si bien qu'il crée un risque de licitation stratégique (par opposition aux offres sincères). Si les offreurs s'engagent dans des stratégies déviantes pour faire face à l'incertitude sur la valeur du bien public, les mécanismes d'enchères perdent leur propriété de compatibilité avec les incitations et révèlent de fausses préférences. Lorsque les prix dépendent des offres soumises, c'est-à-dire en présence de mécanismes de marché répétés avec prix de compensation endogènes, l'hypothèse de l'indépendance des valeurs privées - sous-jacente à la compatibilité avec les incitations - est remise en question ; même si ce type de mécanismes fournit une participation active et un apprentissage du marché. Dans sa vision orthodoxe, le comportement marchand d'adaptation met en péril la compatibilité avec les incitations. Nous introduisons un modèle qui montre que les enchérisseurs licitent suivant l'heuristique d'ancrage et d'ajustement, dépendante d'une fonction de pondération séquentielle, laquelle prend en compte les contraintes de compatibilité avec les incitations sans rejeter les prix signalés issus des autres offres. En déviant de leur ancrage dans le sens du signal public, les enchérisseurs opèrent dans un équilibre corrélé. Comme le prouve l'expérience du Chapitre 2, les contributions privées aux biens publics sont issues d'une démarche d'évaluation. Elles sont conduites aussi bien par des incitations asociales que sociales. Si l'offre privée du bien public est stimulée à la fois par une rationalité qui dicte de ne pas contribuer au bien public et de profiter de l'effort fourni par la collectivité, et par l'appétit pour la reconnaissance sociale qui incite à se faire publiquement connaître en tant que généreux donateur, laquelle des deux motivations domine ? Le Chapitre 4 fait ainsi la comparaison entre déculpabilisation et compétition pour le statut social dans la provision privée des biens publics. Lorsque les agents sont intrinsèquement impulsés, c'est-à-dire qu'ils contribuent essentiellement aux biens publics dans le but de soulager leur culpabilité d'avoir indirectement participé à leur dégradation, ils tendent à se comporter en passagers clandestins. En revanche, lorsque les agents sont extrinsèquement impulsés et se mettent en compétition pour atteindre du statut social qu'ils visent par le financement des biens publics à titre privé, leurs contributions deviennent des compléments stratégiques. Dans ce cas, le niveau agrégé des biens publics croît avec la réduction des écarts de revenus entre les agents. Injecter de la compétition pour le statut social dans des fonctions d'utilité augmente les contributions aux biens publics, et donc leur niveau global, faisant de la concurrence une incitation féconde pour résoudre le problème du passager clandestin.
56

Use the Contingent Valuation Method (CVM) to study the tourists for Penghu National Scenic Area between 2008 to 2011development plan of the economic effect evaluation.

Jan, Sue-lin 04 August 2007 (has links)
Within these years, in order to effectively arrange the limited resource that the government has owned and been able to allocate, a detailed financial plan and a well-structured evaluation system for any project is essential. Normally the most research topics issued are related to the economic effect of natural resources. In Taiwan, the article about analyzing the economic effect about the tour schemes proposed for the development of National Scenic Area is few and only at the beginning stage and the cause mainly is because of the common property of such schemes, i.e. the involvement of different departments needed. At this situation, effected by the different control froces from a varity of government departments and varied industry structures and developing progress in different areas, it is difficult to clarify and analyze the achievement for each department. Owing to this character, the economic effect related to such development schemes is difficult to conclude and it is even harder to evaluate whether or not the economic benefit is definitely resulted from the improving projects. The research topic is going to comprehend the economic effect caused by the medium-range scheme launched by National Scenic Areas, then is able to propose some feasible items to evaluate the economic effect and collect the figures the Cost-Efficiency Evaluation relaed to the effect. As to the intangible benefit, it is assessed by the Contingent Valuation Method (CVM). The study takes the case of Penghu National Scenic Area to predict the economic effect between 2008 to 2011. From the research, it shows that the figure of Willing To Pay (WPA) among the tourists already visited the Penghu National Scenic Area is NT$6,943 and within 2008 and 2011, after the development implemented, the amount is going to raise to NT$9,638. Based on this raise, the economic revenue would be NT$415,691,000 caculated from the Prediction equation in 2008, NT$428,984,000 in 2009, NT$442,397,000 in 2010 and NT$ 455,933,000 in 2011. Within 10 year of available analytic fixed number of years, the 4-year Net Present Value¡]NPV¡^ ¡]valuta of 2008 year ¡^ will be NT$1,766,586,000 based on the discount rate at 2% and the 4 year Benefit-Cost Ratio, B/C ratio is 3.05>1. From this result, the 2008-2011 development plan itself has demostrated its economic feasibility.
57

Application Of Non-market Economic Valuation Method To Value The Environmental Benefits Of Geothermal Energy In Monetary Terms: A Case Study In Yozgat Province

Horasanli, Erol 01 December 2010 (has links) (PDF)
ABSTRACT APPLICATION OF NON-MARKET ECONOMIC VALUATION METHOD TO VALUE THE ENVIRONMENTAL BENEFITS OF GEOTHERMAL ENERGY IN MONETARY TERMS: A CASE STUDY IN YOZGAT PROVINCE Horasanli, Erol M.Sc., Department of Environmental Engineering Supervisor: Assist. Prof. Dr. Emre ALP December 2010, 100 pages Determining environmental economic benefits of geothermal energy is difficult since there is no market for all environmental goods and services related to it. In order to determine and measure the market price of non-market goods and services, non-market valuation methods are used. Since intangible benefits do not have monetary values, non-market valuation techniques are applied to estimate them. Non-market valuation methods are important tools for policy makers in the cost and benefit analysis and environmental impact assessment process to aid their final decision. In this study, the Contingent Valuation Method (CVM) was used to determine the environmental benefits of using geothermal energy for house heating instead of fossil fuels and natural gas in Yozgat (center). The willingness to pay for geothermal energy of the Yozgat residents was determined and underlying motivations to use geothermal energy were assessed. The results showed that the mean willingness to pay (WTP) for the usage of geothermal energy in house heating to increase air quality and mitigate the effects v of climate change is $50/person/month. The results also showed that respondents know the importance of the climate changes and they believe that geothermal energy usage will affect the mitigation of climate changes positively. The geothermal energy investment in the region will amortize itself in 3 years. Therefore, in the feasibility studies, geothermal energy investment seems feasible. During the regression analyses, climate change and air pollution parameters were the most significant parameters for the calculation of mean WTP. Since, decrease in air pollution using geothermal energy, will also mitigate the effect of climate changes, during the geothermal investment in the region, training activities and campaigns should be carried to cover the issues of climate change and global warming to emphasis that geothermal energy will serve for multi-dimensional environmental problems.
58

The value increment of mass-customized products: An empirical assessment

Schreier, Martin 10 August 2006 (has links) (PDF)
The primary argument in favor of mass customization is the delivery of superior customer value. Using willingness-to-pay (WTP) measurements, Franke & Piller (2004) have recently shown that customers designing their own watches with design toolkits are willing to pay premiums of more than 100% (DWTP). In the course of three studies, we found that this type of value increment is not a singular occurrence but might rather be a general phenomenon, as we again found average DWTPs of more than 100% among customers designing their own cell phone covers, T-shirts, and scarves. Building on this, we discuss the sources of benefits that are likely to explain this tremendous value increment. We argue that compared to conventional standard products, a mass-customized product might render the following utilitarian and hedonic benefits: (1) First, the output might be beneficial as self-designed products offer a much closer fit between individual needs and product characteristics. In addition to this mere functional benefit, extra value might also stem from (2) the perceived uniqueness of the self-designed product. As the customer takes on the role of an active codesigner, there may also be two general 'do-it-yourself effects': (3) First, the process of designing per se is likely to allow the customer to meet hedonic or experiential needs (process benefit). (4) Customers may also be likely to value the output of self-design more highly if they take pride in having created something on their own (instead of traditionally buying something created by somebody else). This is referred to as the 'pride of authorship' effect. (author's abstract)
59

The value of Fijian coral reefs by nonusers: a contingent valuation study to investigate willingness-to-pay for conservation, understand scale/magnitude of reef problems and provide tools for practitioners

Fonseca, Carolyn E. 06 July 2009 (has links)
A contingent valuation study was done to investigate the value of Fijian reefs by households in the Metro Atlanta area. Individuals were surveyed and asked questions about their Willingness-to-Pay for coral reef conservation, personal views on the scope/magnitude of coral reef problems, and experience around ocean related activities as well as knowledge. Results from this data, find individuals would donate on average $0.18 taking into account sample and response bias. Less conservative estimates calculated contributions per person to equal $13.9 for the conservation of Fijian reefs. These results imply Atlanta, which is very distant from Fiji, has the potential to contribute to Fijian coral reef conservation programs. Although little empirical work exists on valuation measure for reefs of non-users and groups distant to reefs, this study suggests nonprofits and developing countries could benefit from the inclusion or previously excluded (due to distance to reefs) participants. The study discusses donor characteristics as well as possible market strategies these organizations could utilize to maximize revenue. Findings from this work highlight two important issues rarely discussed in the policy literature: 1-the use of non-market valuation methods to identify stakeholders and 2-the effects of distance on use and non-use value ultimately impacting conservation.
60

Desempenho de reator anaeróbio de fluxo ascendente alimentado com lodo de estação de tratamento de água e esgoto sanitário /

Lombardi, Renata. January 2009 (has links)
Orientador: Roberto Alves de Oliveira / Banca: Wanderley José de Melo / Banca: Marco Antonio Penalva Reali / Resumo: Nas estações de tratamento de água (ETA), as impurezas retiradas da água juntamente com os produtos hidrolisados dos coagulantes dão origem aos resíduos dos decantadores e das águas de lavagem dos filtros, denominados lodo de ETA. Neste experimento, foi avaliado a disposição de lodo de ETA em reatores anaeróbios de fluxo ascendente com manta de lodo (UASB), com volume de 18 L e 38 L, visando o tratamento para destinação adequada do efluente e do lodo excedente dos reatores. Tal experimento foi dividido em quatro ensaios, com tempo de detenção hidráulica de 24 h nos reatores UASB, previamente inoculados com lodo granulado e floculento. Foram observadas condições em que foram aplicadas ao reator UASB, lodo de ETA, com DQOtotal de 161 mg/L e ST de 1.948 mg/L, e misturas de lodo de ETA com esgoto sanitário nas seguintes proporções, em volume, de 1:1 (lodo de ETA : esgoto sanitário) com DQOtotal de 458 mg/L e ST de 3.039 mg/L; 1:3, com DQOtotal de 519 mg/L e ST de 1.562 mg/L e 1:7, com DQOtotal de 1.174 mg/L e ST de 3.502 mg/L. Os valores médios de eficiência de remoção da DQOtotal foram de 75 a 83% e de ST de 73 a 87%. A maior remoção de P foi de 90% e de N de 41%. As eficiências de remoção de Ca, Co, Fe, Mn, Ni, Cu, Pb, Cr e Zn foram superiores a 70%, confirmando a alta capacidade de bioadsorção de metais do lodo anaeróbio. As concentrações de N-am, Fe, Mn, Ni, Cd, Pb, Cu, Cr e Zn atenderam aos padrões de lançamento de efluentes da legislação federal. Ocorreram remoções de E. coli acima de 90%, resultando contagens do efluente de 1,5x10 UFC/100 mL, apresentando qualidade microbiológica correspondente à água doce de classe 1, conforme os padrões estabelecidos na Resolução CONAMA 357/2005 . O lodo do reator UASB apresentou valores de relação SV/ST e E. coli que permitiram o seu uso na agricultura. / Abstract: In water treatment plants (WTP), impurities removed from water mixed with coagulative hydrolytic product create waste of decanters and launderings water filters residues called WTP sludge. In this experiment the WTP sludge disposal in an Upflow Anaerobic Sludge Blanket Reactor (UASB) were evaluated, with a volume of 18 L and 38 L, aiming treatment for appropriate disposal of effluent and excess sludge reactors. Such experiment was divided into four assays, with hydraulic detention time of 24 h in UASB reactors by being inoculated previously with flocculent and granular sludge. It was observed conditions in wich it was added to the UASB reactor WTP sludge with CODtotal of 161 mg/L and TS of 1,948 mg/L, and mixtures of WTP sludge and wastewater in the following amounts, in volume, 1:1 (WTP sludge : wastewater) with CODtotal of 458 mg/L and TS of 3,039 mg/L; 1:3 with CODtotal of 519 mg/L and TS of 3,382 mg/L and 1:7 with CODtotal of 1,174 mg/L and TS 3,501 mg/L. The average values of removal efficiency of CODtotal were 75 the 83% and TS 73 the 87%. The highest P removal was 90% and the highest one of N was 41%. Removal efficiencies of Ca, Co, Fe, Mn, Ni, Cu, Pb, Cr and Zn were higher than 70% wich confirmed the high capacity of biosorption and bioaccumulation of metals from anaerobic sludge. Concentrations of Nam, Fe, Mn, Ni, Cd, Pb, Cu, Cr and Zn fit the quality standards of effluent discharge required by federal legislation. There were removals of E. coli higher than 90% which resulted in counts for effluent of 1.5x10 CFU/100 mL and it showed microbiological quality corresponding to freshwater class 1, according to the standards established in CONAMA Resolution 357/2005. Sludge from the reactor showed ratios of VS /TS and E. coli which allows agricultural use. / Mestre

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