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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

Avalia??o de sistemas de lagoas de estabiliza??o em s?rie no Rio Grande do Norte

Lima, Wedina Rodrigues de 20 February 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-03-09T23:41:38Z No. of bitstreams: 1 WedinaRodriguesDeLima_DISSERT.pdf: 1359852 bytes, checksum: 947641e57effa75408f6f9568cca76ff (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-03-14T19:51:43Z (GMT) No. of bitstreams: 1 WedinaRodriguesDeLima_DISSERT.pdf: 1359852 bytes, checksum: 947641e57effa75408f6f9568cca76ff (MD5) / Made available in DSpace on 2016-03-14T19:51:43Z (GMT). No. of bitstreams: 1 WedinaRodriguesDeLima_DISSERT.pdf: 1359852 bytes, checksum: 947641e57effa75408f6f9568cca76ff (MD5) Previous issue date: 2015-02-20 / As lagoas de estabiliza??o s?o sistemas de tratamento biol?gico que constituem alternativa vantajosa, ao possibilitarem elevada remo??o de mat?ria org?nica e microrganismos patog?nicos, al?m de sua opera??o e manuten??o ser de forma simplificada e com baixo custo. A pesquisa foi realizada em sete sistemas de lagoas de estabiliza??o em s?rie, localizados no Estado do Rio Grande do Norte, compostos por uma lagoa facultativa (LF), seguida de duas lagoas de matura??o (M1 e M2). Com o objetivo de monitorar e avaliar a efici?ncia das lagoas em s?rie, bem como verificar a remo??o de cianobact?rias e microcistina no tratamento, foram realizadas coletas do efluente tratado diretamente nas caixas de sa?da das lagoas facultativas e matura??es, bem como o esgoto bruto (EB) que chegava ?s esta??es. As vari?veis analisadas foram: pH, temperatura, oxig?nio dissolvido, s?lidos suspensos totais, clorofila ?a? , cor aparente, demanda bioqu?mica de oxig?nio (DBO), demanda qu?mica de oxig?nio (DQO), f?sforo total, nitrog?nio org?nico, nitrog?nio amoniacal, nitrog?nio total Kjeldahl, turbidez, densidade de cianobact?rias e concentra??es de microcistina. Foram realizadas an?lises de vari?ncia (ANOVA- an?lise de um fator), observando as premissas utilizando o teste de Tukey. Nos efluentes finais foram verificadas remo??es de DBO de 48,8% (Pipa) a 75,8% (Cai?ara do Rio do Vento) e DQO 57,5% (Pipa) a 83,0% (Santo Ant?nio), respectivamente. As concentra??es m?dias da densidade de cianobact?rias das LF variaram entre 62 x 103 cels.mL-1 (Pedro Velho Ro?a) a 2 x 106 cels.mL-1 (Ponta Negra), enquanto os efluentes finais apresentaram entre a faixa de 9 x 103 cels.mL-1 (Pedro Velho Ro?a) a 1,9 x 106 cels.mL-1 (Macau ? Ilha de Santana). A concentra??o m?xima do efluente final de microcistina foi 0,13 ?g.L-1 (S?o Gon?alo). Em s?ntese, as esta??es de tratamento de esgoto avaliadas, apresentaram uma baixa efici?ncia na remo??o da mat?ria org?nica e de nutrientes. Mas em contrapartida, na maioria das esta??es, foi verificado um bom desempenho referente ? remo??o da densidade de cianobact?rias, bem como o baixo n?vel de concentra??es de microcistina. / Stabilization ponds are biological treatment systems in that stabilization of organic matter is performed by the bacterial oxidation and / or reduction of photosynthetic algae. This study aimed to monitor and evaluate the efficiency of stabilization ponds in the Rio Grande do Norte State. Collections were made of the treated effluent, made directly in the output boxes of facultative lagoons and maturation (M1 and M2) and raw sewage (EB) that arrived at the stations. The variables analyzed were: pH, temperature, dissolved oxygen, total suspended solids, chlorophyll "a", apparent color, total phosphorus, organic nitrogen, ammonia nitrogen, Kjeldahl nitrogen, turbidity, cyanobacteria density and concentrations of microcystin. Variance analysis (ANOVA one way) observing the premises using the Tukey test, so as to check differences between treatments. The evaluate the stations found to COD removals in the bands of 48,8% (Pipa) to 75,8% (Cai?ara Rio do Vento) and 57,5% (Pipa) to 83,0% (Santo Ant?nio), respectively. The mean concentrations of cyanobacteria varied from LFs density of 62,545 cels.mL-1 (Pedro Velho Ro?a) cels.mL-1 to 2,669,048 (Ponta Negra), while the final effluent showed range between 9,072 Cels.mL- 1 (Pedro Velho Ro?a) to 1,899,981 cels.mL-1 (Macau ? Ilha de Santana) and the average concentrations of microcystin the final effluent ranged from 0.02 ?g.L-1 (Ponta Negra) to 0.15 ?g.L-1 (Macau ? Ilha de Santana) at the studied the stations.
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2

Diagn?stico operacional de lagoas de estabiliza??o

Silva Filho, Pedro Alves da 07 May 2007 (has links)
Made available in DSpace on 2014-12-17T15:03:35Z (GMT). No. of bitstreams: 1 PedroASF.pdf: 2737700 bytes, checksum: d21b042ed827c2fb029870f975f7fdcf (MD5) Previous issue date: 2007-05-07 / This work intends to develop an approach based through scientific criteria in the operational diagnosis of ponds of stabilization, starting from analyses accomplished in loco and in laboratory of 78 systems of sewer treatment through ponds of stabilization in the State of Rio Grande do Norte. The objectives of the research are: to map, to evaluate and to diagnose the operational acting of the ponds of stabilization of the state of Rio Grande do Norte, through visits in loco and analyses laboratory; to build a SIG, through the map rain, locate the points of releases of sewages of the systems of existent ponds in Rio Grande do Norte, as well as operational data and his/her respective efficiency diagnosis in the removal of BOD and Coliforms Termotolerantes; to evaluate, in real scale, three systems of ponds of stabilization of RN in the operational efficiency for the parameters BOD5, COD, pH, Temperature, OD and Coliforms Termotolerantes. Of 78 ETEs of appraised RN just, 9% or 7 had maximum concepts in what concerns the removal of BOD and Coliforms Termotolerantes and 41% or 32, they had the worst concepts in term of operational efficiency. The flowing concentrations ETEs of RN of BOD and Coliforms were of 410mg/L and 2,50x107UFC/100ml, the predominant configuration is of the type F1+M1+M2, the relationship BOD/COD revealed for the sewer tributary characteristic biodegradable high. For the study of case of 3 ETEs, the best operational efficiencies in decreasing order were: Cidade (Municipal district), it Ro?a (State) and S?o Miguel (SAAE). The removals of final BOD were 51,6mg/L; 108,27mg/L and 62,6mg/L, tends efficiency of 82%; 74% and 81%. In term of coliforms removal in the final effluentes were 1,90x103UFC/100ml; 1,50x104UFC/100ml and 3,10x104UFC/100ml, tends efficiencies of 99,99%; 99,95% and 99,90%. In what it concerns the practice of agricultural re?so of cultures consumed raw, none of 3 ETEs assisted the parameters of the Resolution CONAMA 357/05, for other re?so practices, all assisted the categories B and C of OMS. For release in body receiving ETE Cidade just, they assist the demands of the resolution of CONAMA 357/05, by study of purification solemnity of the receiving body. The maintenance lack and operation; exclusive operator in ETEs and operation knowledge was the contributory factors for the operational fall in appraised ETEs of RN / Este trabalho se prop?e a desenvolver uma abordagem fundamentada atrav?s de crit?rios cient?ficos no diagn?stico operacional de lagoas de estabiliza??o, a partir de an?lises realizadas in loco e em laborat?rio de 78 sistemas de tratamento de esgoto por meio de lagoas de estabiliza??o no Estado do Rio Grande do Norte. Os objetivos da pesquisa s?o: mapear, avaliar e diagnosticar o desempenho operacional das lagoas de estabiliza??o do estado do Rio Grande do Norte, atrav?s de visitas in loco e an?lises laboratoriais; construir um SIG, atrav?s do mapa hidrogr?fico, locar os pontos de lan?amentos de efluentes dos sistemas de lagoas existentes no Rio Grande do Norte, como tamb?m dados operacionais e seu respectivo diagn?stico de efici?ncia na remo??o de DBO e Coliformes Termotolerantes; avaliar, em escala real, tr?s sistemas de lagoas de estabiliza??o do RN na efici?ncia operacional para os par?metros DBO5, DQO, pH, Temperatura, OD e Coliformes Termotolerantes. Das 78 ETEs do RN avaliadas apenas, 7 lagoas correspondente a 9%, tiveram conceito: Bom, que concerne a remo??o de DBO e Coliformes Termotolerantes e 32 lagoas correspondente a 41%, tiveram conceito: Ruim, em termo de efici?ncia operacional, para os par?metros de DBO e Coliformes Termotolerantes. As concentra??es m?dias afluentes as ETEs do RN de DBO e Coliformes foram de 410mg/L e 2,50x107UFC/100ml, a configura??o predominante ? do tipo F1+M1+M2 (Facultativa prim?ria, seguida por duas lagoas de matura??o, uma prim?ria e outra secund?ria) , a rela??o DBO/DQO revelou para o esgoto afluente caracter?sticas biodegrad?veis. Para o estudo de caso, envolvendo as 3 ETEs, uma para cada ?rg?o de gest?o, as melhores efici?ncias operacionais em ordem decrescente foram: Cidade (Munic?pio), Ro?a (Estado) e S?o Miguel (SAAE). As remo??es de DBO final foram 51,6mg/L; 108,27mg/L e 62,6mg/L, tendo efici?ncia de 82%; 74% e 81%, respectivamente. Em termo de remo??o de coliformes nos efluentes das ETEs foram 1,90x103UFC/100ml; 1,50x104UFC/100ml e 3,10x104UFC/100ml, tendo efici?ncias de 99,99%; 99,95% e 99,90%. No que concerne a pr?tica de re?so de culturas consumidas cruas, nenhumas das 3 ETEs atenderam aos par?metros da Resolu??o CONAMA 357/05, para outras pr?ticas de re?so, todas atenderam as categorias B e C da OMS. Para lan?amento em corpo receptor h?drico apenas a ETE Cidade, atende as exig?ncias da resolu??o do CONAMA 357/05, mediante estudo de autodepura??o do corpo receptor. A falta de manuten??o e opera??o; operador exclusivos nas ETEs e conhecimento de opera??o foram os fatores contribuintes para o diminuto quadro de efici?ncia no que concerne a remo??o final de DBO e Coliformes Termotolerantes nas ETEs avaliadas do RN
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3

Determina??o das emiss?es de metano (CH4) em lagoas de estabiliza??o de dejetos de su?nos na regi?o de Rio Verde-GO / Determination of methane (CH4) in stabilization ponds of swine waste in the region of Rio Verde-GO

SALEH, Bruno Botelho 17 July 2014 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-05-11T18:56:39Z No. of bitstreams: 1 2014 - Bruno Botelho Saleh.pdf: 2346129 bytes, checksum: fe906738dca9a661de96e77fdb8c304a (MD5) / Made available in DSpace on 2017-05-11T18:56:39Z (GMT). No. of bitstreams: 1 2014 - Bruno Botelho Saleh.pdf: 2346129 bytes, checksum: fe906738dca9a661de96e77fdb8c304a (MD5) Previous issue date: 2014-07-17 / CAPES / The city of Rio Verde-GO has excelled for having important agro-industrial units with important breeding of cattle, poultry and pigs. The swine farms handle the liquid waste stabilization ponds with or without digesters systems, accumulating them for 2 months to 4 months, and then applied in areas of approximately 100 to 300 acres. Floating gas collection chambers, where the samples are captured biogas emitted to the atmosphere of stabilization ponds and then analyzed the samples in the laboratory of Embrapa Agrobiology were installed, in addition, to conduct sampling of swine manure (DLS) itself to quantification of elements present in it. It was found in this study that the largest emissions of methane (CH4) were in the following descending order of magnitude: 205.3 ? 68.79 Mg CH4 yr-1 for the fattening farm without biodigester (4,000 swines); 123.94 ? 39.17 Mg CH4 yr-1 in the fattening farm with a biodigester (4,000 swines); 11.22 ? 3.0 ton CH4 year-1 for the producing piglets farm with a biodigester (1,008 matrices swines) and 2.75 ? 0.89 Mg CH4 yr-1 in the producing piglets farm with two biodigesters (728 matrices swines), thus proving expected to their farms in production. Interaction in methane (CH4 Mg yr-1) and concentration (mg L-1) macronutrients (N, P and K) present in the DLS was observed for nitrogen (Ntotal) a linear equation y = 0.1797x ? 111.81 (R2 0.9844); for phosphorus (P) is the linear equation y = 1.4905x ? 25.224 (R2 0.9436); whereas for potassium (K) a linear equation y = 0.0693 ? 35.934 (R2 0.9337). / A cidade de Rio Verde-GO tem se destacado por contar com importantes unidades agroindustriais com importante plantel de bovinos, av?cola e de su?nos. As granjas de su?nos manejam os res?duos l?quidos em sistemas de lagoas de estabiliza??o com ou sem biodigestores, acumulando-os durante 2 meses a 4 meses, sendo ent?o aplicados em ?reas de aproximadamente 100 a 300 hectares. Foram instaladas c?maras flutuantes de coleta de gases, onde foram capturadas as amostras do biog?s emitido para atmosfera das lagoas de estabiliza??o e ent?o analisadas as amostras no laborat?rio da Embrapa Agrobiologia, al?m, da realiza??o de coletas de amostras do pr?prio dejeto l?quido de su?no (DLS) para quantifica??o dos elementos presentes no mesmo. Verificou-se na presente pesquisa que as maiores emiss?es de metano (CH4) ocorreram na seguinte ordem de grandeza decrescente: 205,3 ? 68,79 Mg CH4 ano-1 para a granja em termina??o sem biodigestor (4.000 su?nos); 123,94 ? 39,17 Mg CH4 ano-1 na granja de termina??o com um biodigestor (4.000 su?nos); 11,22 ? 3,0 Mg CH4 ano-1para a granja de produ??o de leit?es com um biodigestor (1.008 matrizes em produ??o) e 2,75 ? 0,89 Mg CH4 ano-1 na granja de produ??o de leit?es com dois biodigestores (728 matrizes em produ??o), comprovando assim o esperado para as respectivas granjas em produ??o. Na intera??o das emiss?es de metano (Mg CH4 ano-1) e a concentra??o (mg L-1) de macronutrientes (N, P e K) presentes nos DLS observou-se para o nitrog?nio (NTotal) uma equa??o linear ? = 0,1797? ? 111,81 (R2 de 0,9844); em rela??o ao f?sforo (P) esta equa??o linear ? = 1,4905? ? 25,224 (R2 de 0,9436); enquanto que para o pot?ssio (K) uma equa??o linear ? = 0,0693? ? 35,934 (R2 de 0,9337).
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4

Intera??es de polissacar?deos sulfatados da macroalga marinha Caulerpa cupressoides var. flabellata com cristais de oxalato de c?lcio

Gomes, Dayanne Lopes 20 July 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-09-19T19:36:42Z No. of bitstreams: 1 DayanneLopesGomes_TESE.pdf: 3794439 bytes, checksum: 0ba5d82fec6f4ee029b8a8f00861a539 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-09-19T22:05:18Z (GMT) No. of bitstreams: 1 DayanneLopesGomes_TESE.pdf: 3794439 bytes, checksum: 0ba5d82fec6f4ee029b8a8f00861a539 (MD5) / Made available in DSpace on 2017-09-19T22:05:19Z (GMT). No. of bitstreams: 1 DayanneLopesGomes_TESE.pdf: 3794439 bytes, checksum: 0ba5d82fec6f4ee029b8a8f00861a539 (MD5) Previous issue date: 2017-07-20 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A urolit?ase afeta aproximadamente 10% da popula??o mundial e est? associada fortemente a forma??o de cristais de oxalato de c?lcio (CaOx). Atualmente n?o existe nenhum composto eficiente que possa ser utilizado para prevenir esta doen?a. No entanto, os polissacar?deos sulfatados (PS) de algas possuem a capacidade de alterar a carga superficial dos cristais de CaOx e assim modificar a din?mica da cristaliza??o, devido ? intera??o das cargas negativas desse pol?mero com a superf?cie do cristal durante sua s?ntese. Nestre trabalho foi verificado o efeito de quatro popula??es de PS extra?dos da alga verde Caulerpa cupressoides var. flabellata na forma??o de cristais de CaOx in vitro. Os PS extra?dos foram nomeados de CCB-F0.3, CCB-F0.5, CCB-F1.0 e CCB-F2.0. An?lises de microscopia eletr?nica de varredura e de potencial zeta mostraram que os polissacar?deos extra?dos modificam a morfologia, o tamanho e a carga superficial dos cristais de CaOx formados na presen?a dos PS. Todos os PS de C. cupressoides induziram o aumento da quantidade de cristais CaOx formados. Contudo, com exce??o de CCB-F2.0, a presen?a dos demais PS levou ? forma??o de cristais de CaOx dihidratados (COD), que s?o comuns em pessoas n?o formadoras de c?lculos. Al?m disso, esses cristais COD apresentaram morfologia arredondada ou em formato de halteres. As an?lises de infravermelho, miscroscopia de fluoresc?ncia, citometria de fluxo e a an?lise de composi??o at?mica (EDS) permitiram a proposi??o de um modelo de intera??o entre os PS de Caulerpa e os cristais COD. Neste modelo, a distribui??o de PS na estrutura do cristal de CaOx ideal para que haja maior estabiliza??o dos cristais COD ? de 2:1:1 entre a base: ?pice: face. Acredita-se que nessa distribui??o os PS consigam evitar a desidrata??o dos cristais COD, tornando-os mais est?veis. Este estudo ? o primeiro passo para entender as intera??es entre PS de C. cupressoides e os cristais de CaOx, que s?o a principal causa de c?lculos renais. / Urolithiasis affects approximately 10% of the world population and is strongly associated with calcium oxalate (CaOx) crystals. Currently, there is no efficient compound that can be used to prevent this disease. However, seaweeds? sulfated polysaccharides (SPs) have the ability to change the CaOx crystals surface?s charge and thus modify the crystallization dynamics, due to the interaction of the negative charges of these polymers with the crystal surface during their synthesis. We observed that the SPs of C. cupressoides modify the morphology, size and surface charge of CaOx crystals. Thus, these crystals are similar to those found in healthy persons. In the presence of SPs, dihydrate CaOx crystals showed rounded or dumbbell morphology. Infrared analyzes, fluorescence microscopy, flow cytometry (FITC-conjugated SPs) and atomic composition analysis (EDS) let us propose the mode of action between the Caulerpa?s SPs and the CaOx crystals. This study is the first step in understanding the interactions between SPs, which are promising molecules for the treatment of urolithiasis, and CaOx crystals, which are the main cause of kidney stones.
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5

Avalia??o de sacolas pl?sticas utilizando espectometria de absor??o at?mica e an?lises t?rmicas / Evaluation of plastic bags using atomic absorption spectrometry and thermal analysis

Gigante, Matheus Silva 31 March 2014 (has links)
Submitted by Setor de Tratamento da Informa??o - BC/PUCRS (tede2@pucrs.br) on 2016-06-01T18:48:34Z No. of bitstreams: 1 DIS_MATHEUS_SILVA_GIGANTE_COMPLETO.pdf: 954118 bytes, checksum: 553cbcaaa8e70eff331d2439adbd8c2c (MD5) / Made available in DSpace on 2016-06-01T18:48:34Z (GMT). No. of bitstreams: 1 DIS_MATHEUS_SILVA_GIGANTE_COMPLETO.pdf: 954118 bytes, checksum: 553cbcaaa8e70eff331d2439adbd8c2c (MD5) Previous issue date: 2014-03-31 / The availability of plastic bags for purchase packing began to popularize in Brazil during the ?80s. It is use, allied with a fast disposal and a slow decomposition results in a large accumulation in landfills, as well as rivers, lakes and seas. The understanding of these materials composition is essential for one to be able to assess the inherent risks involved in it is use and discartament. In this study, eight samples of plastic bags used for packaging were analyzed, being three of them derivated from naphtha, two from ethanol and the three were oxybiodegradable, in which a chemical additive is added to them so that it?s degradability time decreases. The technique of graphite furnace atomic absorption spectrometry was used to determine cadmium, lead, chromium and antimony. Thermal analyzes were also performed to evaluate the thermal stability and the melting temperature of the different types of samples. It was observed the presence of metals in plastic bags analyzed, and only the chromium could be identified in all samples. The metals and metalloids concentration varied between 0.013 and 2.7 ?g g-1, below the maximum limits established by legislation. Through thermal analysis used - thermogravimetric analysis and differential scanning calorimetry - it was observed that all the samples showed the same thermal behavior. Building up the data contents of metals and thermal analysis, it can be inferred that the presence of Cd, Cr, Pb and Sb did not influence the thermal stability of the polymers. / A disponibilidade de sacolas pl?sticas para embalar compras come?ou a se popularizar no Brasil nos anos 80. Seu grande uso, aliado ao r?pido descarte e a demora em se decompor resultam em um grande ac?mulo destas em aterros sanit?rios, bem como em rios, lagos e mares. Visando a redu??o do tempo de decomposi??o, diferentes materiais tem sido utilizados para a confec??o das mesmas. Nesse trabalho, foram analisadas oito amostras de sacolas pl?sticas utilizadas como embalagem sendo tr?s delas provenientes da nafta, outras duas do etanol e tr?s oxibiodegrad?veis (nas quais um aditivo qu?mico ? acrescentado a elas para que o tempo de degradabilidade diminua). Neste trabalho, a t?cnica de espectrometria de absor??o at?mica por forno de grafite foi utilizada para a determina??o de c?dmio, chumbo, antim?nio e cromo e as t?cnicas de an?lise t?rmica foram empregadas para avaliar as propriedades t?rmicas, bem como a temperatura de fus?o dos diferentes tipos de amostras de polietileno. Observou-se a presen?a de metais nas sacolas pl?sticas analisadas, sendo que apenas o cromo p?de ser identificado em todas as amostras. As concentra??es dos metais e metal?ides variaram entre 0,013 e 2,7 ?g g-1, ficando abaixo dos limites m?ximos estabelecidos pela legisla??o. Atrav?s das an?lises t?rmicas utilizadas - an?lise termogravim?trica e calorimetria diferencial explorat?ria - observou-se que as diferentes amostras apresentaram o mesmo comportamento t?rmico. Compilandose os dados de teores de metais e das an?lises t?rmicas, pode-se inferir que a presen?a de Cd, Cr, Pb e Sb n?o influenciou na estabilidade t?rmica dos pol?meros.
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6

S?ntese pelo m?todo pechini e caracteriza??o da zirc?nia dopada com c?rio e neod?mio

Andrade, Izangela Marculino de 21 March 2012 (has links)
Made available in DSpace on 2014-12-17T15:42:16Z (GMT). No. of bitstreams: 1 IzangelaMA_TESE.pdf: 6002351 bytes, checksum: 61a1b03824f174ac0458b386d74608e7 (MD5) Previous issue date: 2012-03-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this study five compositions were synthesized zirconia doped with cerium and neodymium ions in the system Ce10-xNdx Zr90O2 with 0,5 ≤ x ≤ 4,0 using the Pechini method. The powders were characterized by thermogravimetric analysis, differential thermal analysis, infrared spectroscopy and X-ray diffraction, with application of Rietveld refinement of the calcination temperatures of 350?C/3h and 30 minutes at 900?C/3h. All compositions stabilized with a mixture of cubic and tetragonal phase zirconia. The samples were pressed into bars and sintered at 1500?C/3h and 1500?C/6h, being characterized by Xray diffraction, with application of the Rietveld refinement, density and porosity using Archimedes method, scanning electron microscopy and resistance the three point bending. It has been observed the increase in strength with increasing sintering temperature for the compositions x = 2,0 and x = 4,0. For x = 2,0 the main phase was the cubic with 92,56% with crystallite size of 0,56 μm, density and porosity of 96,82% from 1,36%. For x = 4,0 was a mixture of cubic and tetragonal phase with 21% and 37,98%, respectively. The crystallite size was 54,21 nm and 49,64 nm with a density porosity of 97,45% and 1,32% respectively. In the analysis of the fracture surface was observed a greater amount of grain fracture intragranular type, which contribute to increase the mechanical strength of the ceramic. Increased addition of the neodymium ion in the crystal lattice of the zirconium showed a nearly linear behavior with increasing mechanical strength of the zirconia ceramic. Was obtained a bending resistance of 537 ? 38 MPa for the composition x = 2,0 predominantly attributed to cubic phase with 92,56% / No presente trabalho foram sintetizadas cinco composi??es de zirc?nia dopada com ?ons c?rio e neod?mio no sistema Ce10-x.Ndx Zr90O2 com 0,5 ≤ x ≤ 4,0 com o uso do m?todo Pechini. Os p?s foram caracterizados por an?lise termogravim?trica, an?lise t?rmica diferencial, espectroscopia na regi?o do infravermelho e difra??o de raios X, com a aplica??o do refinamento de Rietveld nas temperaturas de calcina??o de 350?C/3h e 30 minutos a 900?C/3h. Todas as composi??es estabilizaram com mistura de fase tetragonal e c?bica da zirc?nia. As amostras foram prensadas em forma de barras e sinterizadas a 1500?C/3h e 1500?C/6h, sendo caracterizadas por difra??o de raios X, com a aplica??o do refinamento de Rietveld, densidade e porosidade usando o m?todo de Arquimedes, microscopia eletr?nica de varredura e resist?ncia a flex?o em tr?s pontos. Foi observado o aumento da resist?ncia mec?nica com o aumento da temperatura de sinteriza??o para as composi??es x=2,0 e x=4,0. Para x=2,0 a fase principal foi ? c?bica com 92,56 % com tamanho de cristalito de 0,56 μm, densidade de 96,82 % e porosidade de 1,36 %. Para x=4,0 ocorreu uma mistura da fase tetragonal e c?bica com 21 % e 37,98 %, repectivamente. O tamanho de cristalitos foi de 54,21 nm e 49,64 nm, com densidade de 97,45 % e porosidade de 1,32 %, respectivamente. Nas an?lises da superf?cie de fratura foi observado uma maior quantidade de gr?os com fratura do tipo intragranular, na qual contribuiu para o aumento da resist?ncia mec?nica da cer?mica. O aumento da adi??o do ?on neod?mio na rede cristalina da zirc?nia apresentou um comportamento quase linear com o aumento da resist?ncia mec?nica da cer?mica de zirc?nia. Foi obtida uma resist?ncia a flex?o de 537 ? 38 MPa para a composi??o x=2,0 atribu?da a predomin?ncia da fase c?bica com 92,56 %
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Tratamento e reaproveitamento de res?duos de su?nos como biofertilizante na cafeicultura. / Treatment and reuse of waste from pigs as biofertilizer in coffee production.

Sousa, Francine Aparecida 16 July 2010 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T13:30:32Z No. of bitstreams: 5 23.pdf: 968729 bytes, checksum: 708a2fc2af8284a6b22a75db644cadea (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20904 bytes, checksum: e09bf99e64678e4285abf3ef3e05412d (MD5) license_rdf: 23422 bytes, checksum: b145eda3d84bdc4f56b389c0ab98d368 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-02-27T16:52:06Z (GMT) No. of bitstreams: 5 23.pdf: 968729 bytes, checksum: 708a2fc2af8284a6b22a75db644cadea (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20904 bytes, checksum: e09bf99e64678e4285abf3ef3e05412d (MD5) license_rdf: 23422 bytes, checksum: b145eda3d84bdc4f56b389c0ab98d368 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-02-27T16:52:06Z (GMT). No. of bitstreams: 5 23.pdf: 968729 bytes, checksum: 708a2fc2af8284a6b22a75db644cadea (MD5) license_url: 49 bytes, checksum: fd26723f8d7edacdb29e3f03465c3b03 (MD5) license_text: 20904 bytes, checksum: e09bf99e64678e4285abf3ef3e05412d (MD5) license_rdf: 23422 bytes, checksum: b145eda3d84bdc4f56b389c0ab98d368 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2010 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / A distribui??o como biofertilizantes ? uma alternativa vi?vel para a destina??o dos dejetos produzidos na suinocultura, j? que eles possuem nutrientes tais como f?sforo, nitrog?nio, entre outros. Diante disso, o objetivo deste trabalho foi caracterizar os par?metros f?sico-qu?micos de dejetos l?quidos de su?nos (DLS), tratados em sistema de lagoas em s?rie e avaliar as altera??es nos atributos microbiol?gicos de um solo cultivado com caf? ap?s aplica??o de diferentes doses de DLS. O estudo foi conduzido na Granja Campo Alegre e na Fazenda Yamaguchi, no Munic?pio de Diamantina, Minas Gerais. Os DLS foram coletados em v?rios pontos: sa?da das instala??es, sa?da da lagoa anaer?bia, sa?da da primeira lagoa facultativa e sa?da da segunda lagoa facultativa, sendo analisados: Demanda Qu?mica de Oxig?nio (DQOt), Demanda Bioqu?mica de Oxig?nio (DBO5), Concentra??o de S?lidos Totais (ST), Nitrog?nio Total (N-Total), F?sforo, Pot?ssio, Zinco e Cobre. Ap?s an?lise, os dejetos foram aplicados em um cafeeiro, em experimento, constitu?do por cinco tratamentos com cinco repeti??es. As amostras de solo foram coletadas, na camada de 0-10 cm, de profundidade. Foram avaliados a respira??o basal, o carbono da biomassa microbiana e determinado o quociente metab?lico. Os resultados permitiram constatar que o sistema de lagoas de estabiliza??o em s?rie apresenta 88% de efici?ncia na remo??o de DQOt e 91% na remo??o de DBO5. As fra??es de s?lidos apresentaram comportamento semelhante e a efici?ncia de remo??o de N-Total correspondeu a 24,2%. O uso de dejetos l?quidos de su?nos no solo, antes e 30 dias ap?s sua aplica??o, aumentou a biomassa microbiana do solo e a atividade microbiana. Os resultados obtidos permitem concluir que o sistema de lagoas de estabiliza??o em s?rie demonstra ser eficiente na remo??o do excesso de nutrientes. Ressalte-se que o tratamento demonstrou caracter?sticas favor?veis ao reaproveitamento dos dejetos como biofertilizante. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Produ??o Vegetal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2010. / ABSTRACT The distribution in biofertilizer form is a feasible alternative for disposal of waste produced by pigs, since they have nutrients such as phosphorus, nitrogen, among others. Therefore, the objective of this study was to characterize the physical and chemical parameters of pig slurry (DLS), treated in a system of ponds in series and evaluate the changes in the microbial soil of a coffee plantation after applying different doses of pig slurry. The study was conducted in the Campo Alegre Farm and Ranch Yamaguchi in the city of Diamantina, Minas Gerais. The DLS were collected at various points: exit of the facilities, exit of the anaerobic pond, exit of the first facultative pond, exit of the second facultative pond, and analyzed: Chemical Oxygen Demand (DQOt), Biochemical Oxygen Demand (BOD5) concentration Total Solids (DS), Total Nitrogen (Total-N), Phosphorus, Potassium, Zinc, and Copper. After analysis, the pig manure were applied in a coffee plantation, in an experiment consisting of five treatments with five replications. Soil samples were collected at 0-10 cm depth. It was evaluated the basal respiration, microbial biomass carbon and metabolic quotient determined. The results show that the system of stabilization ponds in series features 88% efficiency in removing DQOt and 91% for BOD5 removal. The fractions of solids showed similar behavior and t removal efficiency of Total-N accounted for 24.2%. Use of pig slurry in soil, before and 30 days after application, amplified the soil microbial biomass and microbial activity. The results showed that the system of stabilization ponds in series proves to be effective in removing excess nutrients. It is noteworthy that treatment showed favorable characteristics for reuse of wastes as biofertilizers.
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8

Incorpora??o de res?duo de perfura??o em matriz cer?mica: estabiliza??o por solidifica??o / Residue incorporation drilling ceramic matrix: stabilization by solidilication

C?mara, Ana Paula Costa 29 July 2013 (has links)
Made available in DSpace on 2014-12-17T15:01:56Z (GMT). No. of bitstreams: 1 AnaPCC_TESE_Parcial.pdf: 421102 bytes, checksum: 073b73c95b7ac8b4269179af4e3a1726 (MD5) Previous issue date: 2013-07-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / One of the waste generated during the drilling of oil wells are gravel which are impregnated of drilling fluid. This residue consists of highly toxic chemicals, including toxic metals. This study suggests an alternative process to the treatment of this waste, by incorporating it the form of raw material in the ceramic matrix , and by solidification and stabilize the metals present, Aluminum (Al), Iron (Fe), Manganese (Mn) and Zinc (Zn). The raw materials were characterized by the techniques of X ray fluorescence (FRX), X ray diffraction (DRX), laser granulometry (GL), thermogravimetry (TG) and differential thermal analysis (ADT). To evaluate the percentage of gravel effect the environmental and technological properties were obtained from formulations containing 0, 10 and 20 % by weight of gravel in the ceramic matrix. After sintering at temperatures 1080, 1120 and 1160 ?C, the samples were tested for water absorption, the linear shrinkage firing, voltage of rupture and solubility. The results obtained showed that the stabilization by solidification, is a viable alternative to safe disposal of waste drilling. Ceramics products can be used in the manufacture of solid bricks / Um dos res?duos gerados durante a perfura??o de po?os de petr?leo s?o os cascalhos que ficam impregnados por fluido de perfura??o. Este res?duo ? composto por produtos qu?micos de alta toxidade, entre eles os metais t?xicos. Este estudo prop?e um processo alternativo ao tratamento deste res?duo, incorporando-o na forma de mat?ria-prima em matriz cer?mica, e atrav?s da solidifica??o estabilizar os metais t?xicos presentes, Alum?nio (Al), Ferro (Fe), Mangan?s (Mn) e Zinco (Zn). As mat?rias-primas foram caracterizadas por fluoresc?ncia de raios X (FRX), difratometria de raios X (DRX), granulometria a laser (GL), termogravimetria (TG) e an?lise t?rmica diferencial (ADT). Para avaliar o efeito do percentual de cascalho nas propriedades tecnol?gicas e ambiental, foram obtidas formula??es contendo 0, 10 e 20 % em massa do cascalho na matriz cer?mica. Ap?s sinteriza??o ?s temperaturas de 1080, 1120 e 1160 ?C, as amostras foram submetidas a ensaios de absor??o de ?gua, retra??o linear de queima, tens?o de ruptura ? flex?o e solubilidade. Os resultados alcan?ados mostraram que a t?cnica de estabiliza??o por solidifica??o, ? uma alternativa vi?vel a destina??o segura do res?duo de perfura??o. Os produtos cer?micos obtidos podem ser utilizados na fabrica??o de tijolos maci?os e blocos cer?micos de alvenaria, em determinados percentuais e temperaturas de queima descritas neste trabalho / 2020-01-01
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9

Avalia??o da efici?ncia de lagoas de estabiliza??o no tratamento de res?duos esgotados de fossas s?pticas

Medeiros, Daniel Dantas Viana 20 August 2009 (has links)
Made available in DSpace on 2014-12-17T15:03:21Z (GMT). No. of bitstreams: 1 DanielDVM.pdf: 2848336 bytes, checksum: 2d942e41371b022b9b35b5e7499260d3 (MD5) Previous issue date: 2009-08-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Because of disability in public policy development in mind to attend issues of sanitation in the municipalities, companies known as "clean-blue" appeared proposing to solve a simple collection and management of wastewater produced in single or multifamily residences, commercial, hospitals, etc. In the case of an activity in which there are no worries about the fate of sewage, emerged some doubts about the degree of health and environmental safety in these companies. Traditionally, most of them makes the provision of waste depleted soil or wetland, open, usually located on the outskirts of cities (MENESES, 2001). In turn, the sludge from septic tanks exhausted, provided no technical criteria - in the soil, rivers and as an agricultural fertilizer put in risk the health of the population and environmental quality. This work was entered in the search network 5 of the Notice of the Research Program in Sanitation - PROSAB-5, aimed to study the theme 'Characterization and study of alternative ways of treating sludge from septic tanks in the city of Natal, RN', proposing to evaluate the performance of the use of stabilization ponds as a system to handle waste from septic tanks exhausted. A series of lakes studied belong to one of the largest clean-pit of Natal, consisting of two anaerobic ponds, one facultative and maturation, and a tank disinfection, the wastewater being released in the Potengi River. Samples were collected between the months of October 2007 to October 2008, at six points previously defined and judged as more appropriate to what is proposed study. The analysis results in field and laboratory showed the most significant removal of COD (88.93%), total suspended solids (94.87%), organic nitrogen (66.87%) and thermotolerant coliforms (99.88%). Some results have not reached the expected because the system under study had operating problems that have undermined the efficiency of the reactors / Por causa da defici?ncia na elabora??o de pol?ticas p?blicas em aten??o ao atendimento ?s quest?es do esgotamento sanit?rio dos munic?pios, empresas conhecidas como limpa-fossa surgiram propondo solucionar de forma simples a coleta e o manejo dos efluentes l?quidos produzidos em resid?ncias uni ou multifamiliares, com?rcio, hospitais, etc. Em se tratando de uma atividade em que n?o h? preocupa??es quanto ao destino dos esgotos, surgiram questionamentos referentes ao grau de seguran?a sanit?ria e ambiental nessas empresas. Tradicionalmente, a maioria delas faz a disposi??o dos res?duos esgotados no solo ou em ?reas inund?veis, a c?u aberto, normalmente localizadas na periferia das cidades (MENESES, 2001). Por sua vez, o lodo esgotado de fossas s?pticas, disposto sem qualquer crit?rio t?cnico no solo, em rios e como adubo na agricultura , coloca em risco a sa?de da popula??o e a qualidade ambiental. O presente trabalho, inserido na rede de pesquisa do Edital 5 do Programa de Pesquisas em Saneamento B?sico PROSAB-5, objetivou o estudo do tema Caracteriza??o e estudo de alternativas de tratamento de lodos de fossa s?ptica na cidade do Natal, RN , propondo a avalia??o do desempenho do uso das lagoas de estabiliza??o como sistema de tratamento dos res?duos esgotados das fossas s?pticas. A s?rie de lagoas estudada pertence a uma das maiores empresas limpa-fossa da cidade de Natal, composta por duas lagoas anaer?bias, uma facultativa e uma de matura??o, al?m de um tanque de desinfec??o, sendo o efluente final lan?ado no Rio Potengi. As coletas foram realizadas entre os meses de outubro de 2007 a outubro de 2008, em seis pontos previamente definidos e julgados como mais adequados ao que se prop?s estudar. Os resultados das an?lises em campo e em laborat?rio apontaram remo??es mais significativas de DQO (88,93%), s?lidos suspensos totais (94,87%), nitrog?nio org?nico (66,87%) e coliformes termotolerantes (99,88%). Alguns resultados obtidos n?o atingiram o esperado, pois o sistema em estudo apresentou problemas de opera??o que prejudicaram a efici?ncia dos reatores
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10

Flota??o por ar dissolvido como p?s-tratamento de efluentes de lagoas de estabiliza??o

Brito, Andr? C?mara de 08 July 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-12T14:42:23Z No. of bitstreams: 1 AndreCamaraDeBrito_DISSERT.pdf: 1740307 bytes, checksum: 2791cedd5bfccff8d9fbd2dc3410084e (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-18T14:38:30Z (GMT) No. of bitstreams: 1 AndreCamaraDeBrito_DISSERT.pdf: 1740307 bytes, checksum: 2791cedd5bfccff8d9fbd2dc3410084e (MD5) / Made available in DSpace on 2017-01-18T14:38:30Z (GMT). No. of bitstreams: 1 AndreCamaraDeBrito_DISSERT.pdf: 1740307 bytes, checksum: 2791cedd5bfccff8d9fbd2dc3410084e (MD5) Previous issue date: 2016-07-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Para tratamento de esgotos dom?sticos lagoas de estabiliza??o possuem importantes vantagens, como elevada efici?ncia na remo??o de mat?ria org?nica e organismos patog?nicos, n?o utiliza??o de energia el?trica e facilidade operacional, principalmente em regi?es de clima tropical. Por outro lado, uma de suas desvantagens ? a elevada concentra??o de s?lidos suspensos, principalmente devido a biomassa algal. O objetivo desta pesquisa foi avaliar a efici?ncia de remo??o da flota??o por ar dissolvido (FAD) no p?s-tratamento de efluentes de lagoas de estabiliza??o. Para os ensaios com a FAD (coagula??o-flocula??o-flota??o) foi utilizado um flotateste de bancada. Foi planejado um delineamento experimental tipo fatorial aleat?rio, utilizando o crit?rio ka-1, em que k ? o n?mero de n?veis (k=3: menor, central, maior) e a ? o n?mero de fatores (a=4: dose de coagulante, taxa de recircula??o de ?gua saturada, pH e tempo de flocula??o), com ensaios realizados em triplicata, para os coagulantes policloreto de alum?nio e cloreto f?rrico em efluente de lagoas de facultativa prim?ria e lagoa de matura??o. As amostras do efluente da lagoa facultativa e efluente final da ETE Ponta Negra (Natal) foram coletadas semanalmente, no per?odo da manh?. As seguintes vari?veis foram avaliadas nos efluentes brutos e ap?s os ensaios com FAD: turbidez, s?lidos suspensos totais, cor aparente, DQO, clorofila ?a?, fosforo total, ortofosfato sol?vel e nitrog?nio amoniacal e org?nico. A vari?vel operacional com maior influ?ncia na remo??o as vari?veis avaliadas foi a dose de coagulante para o coagulante PAC e para o coagulante cloreto f?rrico a maior influ?ncia na remo??o das vari?veis foi o pH seguido da dosagem de coagulante. A partir da dosagem otimizada as remo??es nos par?metros analisados atingiram valores entre 66% e 97%. O p?s-tratamento na lagoa facultativa obteve o maior percentual de remo??o nas vari?veis analisadas para os dois coagulantes, assim como o cloreto f?rrico obtive maiores percentuais de remo??o em todas as situa??es. / For treatment of wastewater stabilization ponds have important advantages, such as high efficiency in removing organic matter and pathogens, non-use of electricity and operational ease, especially in tropical regions. On the other hand, one of its disadvantages is the high concentration of suspended solids, mostly due to algal biomass. The objective of this research was to evaluate the removal efficiency flotation by dissolved air (FAD) in the post-treatment stabilization ponds effluent. For tests with the FAD (coagulation-flocculation-flotation) we used a bench flotateste. a random factorial experimental design was planned using the ka-1 criterion, where k is the number of levels (k = 3: low, middle, major) and a is the number of factors (a = 4: coagulant dose saturated, water recirculation rate, pH and flocculation time) with assays performed in triplicate for the coagulant polyaluminium chloride, ferric chloride effluent primary facultative lagoons and maturation pond. Samples of the effluent from the facultative pond and final effluent from the WWTP Ponta Negra (Natal) were collected weekly in the morning. The following variables were evaluated in the raw wastewater and after the tests with FAD: turbidity, total suspended solids, apparent color, COD, chlorophyll "a", total phosphorus, orthophosphate soluble and ammonia and organic nitrogen. The operational variable with higher influence on the removal variables was evaluated coagulant dose for the PAC coagulant and the coagulant ferric chloride to remove the greatest influence variable was the pH followed by coagulant dosage. From the optimized dosage removals in the analyzed parameters reached values between 66% and 97%. The post-treatment in the facultative pond had the highest percentage removal in variables for the two coagulants, and ferric chloride got higher removal percentages in all situations.
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