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An?lise do comportamento reol?gico de pastas de cimento contendo res?duos de pneu para po?os de petr?leo / Analysis of the rheological behavior of cement pastes containing tire residues for oil wellsMelo, Abimael Lopes de 20 March 2009 (has links)
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Previous issue date: 2009-03-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The low tenacity presented by the Portland cement pastes used in the oil wells cementation has been motivating several researches with attention focused on alternative materials. Additives have been developed to generate flexible pastes with mechanical resistance capable to support the expansions and retractions of the metallic covering of the wells that submit to the steam injection, technique very used to increase the recovery factor in oil reservoirs with high viscosity. A fresh paste with inadequate rheological behavior may commit the cementation process seriously, involving flaws that affect the performance of the paste substantially in the hardened state. This work proposes the elaboration and the rheological analysis of Portland cement pastes with addition of residues of rubber tire in several proportions, with the aim of minimizing the damages provoked in the hem cementing of these wells. By thermogravimetric analysis, the particles of eraser that go by the sieve of 0,5mm (35
mesh) opening and treated superficially with NaOH solution of 1 mol/L presented appropriate thermal resistance for wells that submit to thermal cyclic. The evaluation of the study based on the results of the rheological analysis of the pastes,
complemented by the mechanical analysis, thickening, stability, tenor of free water and filtrate loss, being used as parameter a paste reference, without rubber addition.
The results showed satisfactory rheology, passive of few corrections; considerable loss of mechanical resistance (traction and compression), compensated by earnings
of tenacity, however with established limits for its application in oil wells; satisfactory stability, free water and thickening time / A baixa tenacidade apresentada pelas pastas de cimentos Portland utilizadas na cimenta??o de po?os de petr?leo tem motivado v?rias pesquisas voltadas para materiais alternativos. Aditivos t?m sido desenvolvidos para gerar pastas flex?veis e com resist?ncia mec?nica capaz de suportar as expans?es e retra??es do revestimento met?lico dos po?os que se sujeitam ? inje??o de vapor, t?cnica muito utilizada para aumentar o fator de recupera??o em reservat?rios de ?leo com alta viscosidade. Uma pasta fresca com comportamento reol?gico inadequado pode comprometer seriamente o processo de cimenta??o, implicando em falhas que afetam substancialmente o desempenho da pasta no estado endurecido. Este trabalho prop?e a elabora??o e a an?lise reol?gica de pastas de cimento Portland com adi??o de res?duos de borracha de pneu em diversas propor??es, com o objetivo de minimizar os estragos provocados na bainha cimentante destes po?os. Por an?lise termogravim?trica, as part?culas de borracha passantes na peneira de abertura 0,5 mm (35 mesh) e tratadas superficialmente com solu??o 1 mol/L de NaOH, apresentaram resist?ncia t?rmica adequada para po?os sujeitos ? ciclagem t?rmica. A avalia??o do estudo baseou-se nos resultados da an?lise reol?gica das pastas, complementadas pela an?lise mec?nica, espessamento, estabilidade, teor de ?gua livre e perda de filtrado, utilizando-se como par?metro uma pasta refer?ncia, sem adi??o de borracha. Os resultados mostraram reologia satisfat?ria, passiva de poucas corre??es; consider?vel perda de resist?ncia mec?nica (tra??o e compress?o), compensada por ganho de tenacidade, por?m dentro dos limites
estabelecidos para sua aplica??o em po?os de petr?leo; satisfat?ria estabilidade, ?gua livre e tempo de espessamento
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Estudo do comportamento pl?stico, mec?nico, microestrutural e t?rmico do concreto produzido com res?duo de porcelanatoSouza, Paulo Alysson Brilhante Faheina de 21 December 2007 (has links)
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Previous issue date: 2007-12-21 / Population growth experienced in major cities, allied to society s need of infra-structure, especially ones related to habitational demands, increases the consumption of construction materials. As a consequence, consumption of natural resources itself. Thus, due to this process, concrete is one of the most produced materials in civil construction. This is also due to the great diversity of its application, easiness in its execution and adequate mechanical performance, as well as low production costs. Following the same tendencies in construction development, the ceramic industry has intensified the production of porcelain ceramic tiles and floors. These are achieved by a fine finishing and receive polishing at the end of the fabrication process. This work researched the use of porcelain residues in polishing for the production of concrete. All of which; due to economical and environmental issues. This process aims to prove adequate destiny for this type of residue, due to environmental issues, incorporating it to the concrete itself; all of which provides economy in consumption of the materials that constitute concrete. Thus, the main characteristics of concrete were investigated through the inclusion of different concentration of the porcelain residue as additional trait element. The residue rates incorporated to the trait varied from 10% to 50% in relation to the cement mass, in the traits with plastic additives and without plastic additives. It is observed that the inclusion of porcelain residue produced a meaningful alteration in the consistency of fresh concrete. This residue has a fine granulometry and it considerably absorbed the water used in the concrete spreading, influencing the way this material is dealt with. Thus, the value of cement striking decreases with the increase of residues present in trait. The maximal incorporation of the residue was of 50%, massively, for the same factor water/initial cement. The use of residues in concrete results in an 40% increase in the compression resistance. It is also proportional to residue concentration of porcelain in the trait. The microstructure was also favored once porosity and concrete absorption decreases with the use of this residue. The parameters demonstrate the quality and durability of the concrete produced with this residue. The use of porcelain residue in concrete composition has not produced meaningful thermal behavior changes. Thermal conductivity, heat capacity and thermal diffusivity have been maintained basically constant / O crescimento populacional nos grandes centros, aliado a necessidade de gera??o de infra-estrutura ? sociedade, est? obrigando a ind?stria da constru??o civil a intensificar suas atividade, principalmente no que se refere ? demanda habitacional, resultando no aumento do consumo de materiais de constru??o e, consequentemente, dos recursos naturais. Decorrente desse processo, o concreto destaca-se como um dos materiais mais produzidos na constru??o civil, pela grande diversidade de aplica??o, facilidade de execu??o e adequado desempenho mec?nico, al?m de apresentar baixo custo de produ??o. Seguindo a mesma tend?ncia de desenvolvimento da constru??o, a ind?stria cer?mica tem intensificado a produ??o de pisos cer?micos do tipo porcelanato, que consistem em elementos de acabamento fino e, por isso, recebem polimento ao final do processo de fabrica??o. Este trabalho pesquisou o emprego do res?duo do polimento de porcelanato para a produ??o de concreto por motivos econ?micos e ambientais. O objetivo consiste em gerar um destino adequado para o res?duo, por motivos ambientais, incorporando-o ao concreto, e, ainda, propiciar uma economia no consumo dos materiais constituintes do concreto. Para tanto, foram investigadas as principais caracter?sticas do concreto a partir da inclus?o de diferentes concentra??es do res?duo de porcelanato como elemento adicional no tra?o. Os teores de res?duo incorporados ao tra?o variaram de 10% a 50% em rela??o ? massa de cimento, em tra?os com aditivo plastificante e sem aditivo plastificante. O acr?scimo do res?duo de porcelanato alterou significativamente a consist?ncia do concreto fresco. O res?duo apresenta uma granulometria muito fina e, por isso, absorveu consideravelmente a ?gua de amassamento do concreto, influenciando, assim, na trabalhabilidade do mesmo. Portanto, o valor do abatimento diminui com o aumento da concentra??o do res?duo no tra?o. A incorpora??o m?xima de res?duo foi de 50% , em massa, para o mesmo fator ?gua/cimento inicial. A utiliza??o do res?duo no concreto resultou em um aumento de at? 40% na resist?ncia ? compress?o, sendo proporcional a concentra??o do res?duo de porcelanato no tra?o. A microestrutura tamb?m foi favorecida, ? medida que a porosidade e a absor??o do concreto diminu?ram com a utiliza??o do res?duo. Esses par?metros atestam a qualidade e a durabilidade do concreto produzido com res?duo. A utiliza??o do res?duo de porcelanato na composi??o do concreto n?o gerou mudan?as significativas no comportamento t?rmico. A condutividade t?rmica, a capacidade calor?fica e a difusividade t?rmica se mantiveram basicamente constantes
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Concreto celular polim?rico: influ?ncia na adi??o de res?duo de poli?ster insaturado termofixoMelo, Guilherme F?bio de 23 March 2009 (has links)
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Previous issue date: 2009-03-23 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / This work addresses the production of lightweight concrete building elements, such as plates, prefabricated slabs for pre-molded and panels of fencing, presenting a singular
concrete: the Lightweight Concrete, with special properties such low density and good strength, by means of the joint use of industrial waste of thermosetting unsaturated
polyesters and biodegradable foaming agent, named Polymeric Lightweight Concrete. This study covered various features of the materials used in the composition of the Polymeric Lightweight Concrete, using a planning of factorial design 23, aiming at studying of the strength, production, dosage processes, characterization of mechanical properties and microstructural analysis of the transition zone between the light artificial aggregate and the matrix of cement. The results of the mechanical strength tests were analyzed using a computational statistics tool (Statistica software) to understand the behavior and obtain the ideal quantity of each material used in the formula of the Polymeric Lightweight Concrete. The definition of the ideal formula has the purpose of obtaining a material with the lowest possible dry density and resistance to compression in accordance with NBR 12.646/92 (≥ 2.5 MPa after 28 days). In the microstructural
characterization by scanning electron microscopy it was observed an influence of the materials in the process of cement hydration, showing good interaction between the
wrinkled face of the residue of unsaturated polyesters thermosetting and putty and, consequently, the final strength. The attaining of an ideal formula, given the Brazilian
standards, the experimental results obtained in the characterization and comparison of these results with conventional materials, confirmed that the developed Polymeric Lightweight Concrete is suitable for the production of building elements that are advantageous for construction / Neste trabalho ? abordada a aplica??o da tecnologia dos concretos leves ? produ??o de elementos construtivos, tais como placas pr?-fabricadas para lajes pr?-moldadas, pain?is
de veda??o e pe?as pr?-moldadas, e ao desenvolvimento de um concreto celular com propriedades especiais de baixa densidade e boa resist?ncia mec?nica, em fun??o da
utiliza??o conjunta de res?duo industrial de poli?ster insaturado termofixo (PIT) e espuma biodegrad?vel incorporadora de ar, denominado de Concreto Celular
Polim?rico (CCP) . O estudo abrangeu diferentes tra?os dos materiais empregados na composi??o do CCP, sendo utilizado um planejamento fatorial 23, para an?lises dos processos de dosagem e produ??o, caracteriza??o das propriedades mec?nicas, bem como an?lises microestruturais da zona de transi??o entre o agregado artificial leve (PIT) e a matriz de cimento. Os resultados dos testes de resist?ncia mec?nica foram analisados utilizando-se uma ferramenta computacional de estat?stica (Statistica Software) para compreens?o do comportamento e obten??o da concentra??o ideal de
cada material utilizado na formula??o do CCP. A defini??o da f?rmula ideal teve como finalidade a obten??o de um material com a menor densidade a seco poss?vel e resist?ncia ? compress?o que atendesse ? norma NBR 12.646/92 (≥ 2,5 MPa aos 28 dias). Na caracteriza??o microestrutural por microscopia eletr?nica de varredura, observou-se a influ?ncia dos materiais no processo de hidrata??o do cimento, onde
constatou-se boa intera??o entre o res?duo de PIT, cuja face ? enrugada, e a pasta de cimento. A obten??o da formula??o de um novo material que atende ? norma brasileira, os resultados experimentais obtidos nas caracteriza??es e compara??o desses resultados com materiais convencionais, comprovaram que o Concreto Celular Polim?rico desenvolvido ? adequado ? produ??o de elementos construtivos que apresentam vantagens quando aplicados ? constru??o civil
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Estudo da adi??o do res?duo proveniente da extra??o de min?rio de ferro em argilas do Rio Grande do NorteChaves, Leonardo Flamarion Marques 30 October 2009 (has links)
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Previous issue date: 2009-10-30 / The mining industry is responsible for the generation of waste from their natural process of extraction. The mining impacts in urban areas are of special importance due to the high urban occupation, which are exacerbated due to the proximity of the mined areas and populated areas. Some solutions to wastedisposal have the potential to significantly reduce the environmental risks and liabilities, but represent higher costs in the stages of deployment and operation. The addition of mining waste as raw material in the development of commercial products reduces the environmental impacts, transforming the waste into a positive element in the generation of employment and income. This thesis studies the incorporation of waste iron ore in two clays, one from the ceramic industry of the City of Natal and the other from the ceramic industry of the Serid? Region, both in the State of Rio Grande do Norte, Brazil. Percentages of iron ore waste of 5%, 10% , 15%, 20%, 25% and 30% were used in the tested ceramic matrix. The two clays and the iron ore waste used as part of this investigation were characterized by X-ray diffraction tests, X-ray fluorescence tests, differential thermal analysis, thermogravimetric analysis and dilatometric analysis. The samples were sintered under temperatures of 850 ?C, 950 ?C and 1050?C at a heating rate of 5 ?C/min with isotherms of two hours. The following tests were performed with the samples: linear shrinkage, water absorption, apparent porosity, apparent density, mass loss in fire and bending resistance in order to obtain their physical and mechanical properties. An amount of 5% of waste iron ore in the matrix clay at a temperature of 850 0C resulted in na increase of about 65% in the tensile strength of the clay samples from the Natal ceramic industry. A linear shrinkage of only 0.12% was observed for the samples, which indicates that the physical properties of the final product were not influenced by the addition of the waste / A ind?stria extrativa mineral ? respons?vel pela gera??o de res?duos provenientes do seu processo natural de extra??o. Os impactos da minera??o em ?rea urbana revestem-se de especial import?ncia devido ao alto grau de ocupa??o urbana, que s?o agravados face ? proximidade entre as ?reas mineradas e as ?reas habitadas. Algumas solu??es de disposi??o de res?duos t?m potencial de reduzir significativamente os riscos e o passivo ambiental, por?m representam custos elevados nas etapas de implanta??o e de opera??o. A adi??o de res?duos de min?rio de ferro como mat?ria-prima na elabora??o de produtos que s?o utilizados comercialmente tem como objetivo diminuir os impactos ambientais, transformando esses res?duos em elementos positivos na gera??o de trabalho e renda. O presente trabalho estuda a incorpora??o de res?duo de min?rio de ferro em duas argilas, uma do p?lo cer?mico da Grande Natal e outra do p?lo cer?mico da Regi?o do Serid?, ambas do Estado do Rio Grande do Norte, em percentuais de 5%, 10%, 15%, 20%, 25% e 30%, com o intuito de verificar a potencialidade da incorpora??o do res?duo em matriz cer?mica. As mat?rias-primas foram caracterizadas atrav?s dos ensaios de difra??o de raios X, fluoresc?ncia de raios X, an?lise t?rmica diferencial, an?lise termogravim?trica e an?lise dilatom?trica. Os corpos-de-prova foram conformados e em seguida sinterizados nas temperaturas de 850 ?C, 950 ?C e 1050 ?C, ? taxa de aquecimento de 5 ?C/min, com iso terma de duas horas. Foram realizados os ensaios tecnol?gicos de retra??o linear de queima, absor??o de ?gua, porosidade aparente, massa espec?fica aparente, perda demassa ao fogo e tens?o de ruptura ? flex?o, com o intuito de se obter suas propriedades f?sicas e mec?nica. A argila do p?lo cer?mico da Grande Natal apresentou um aumento em torno de 65% na tens?o de ruptura ? flex?o, com um percentual ?nfimo de 0,12% na sua retra??o linear de queima, quando adicionados 5% de res?duo de min?rio de ferro na matriz de argila ? temperatura de 850 ?C, n?o comprometendo assim as p ropriedades f?sicas do produto final
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S?ntese de ze?litas e argilas ?cidas pilarizadas a partir de mat?rias primas naturaisBieseki, Lindiane 20 July 2012 (has links)
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Previous issue date: 2012-07-20 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Structural changes in waste for zeolites synthesis are subject of many studies carried
out in the synthesis of molecular sieves. These materials are named molecular sieves because
they have well defined pore sizes and they have the capacity of select molecules by its size. In
this work, it was studied the synthesis processes of two types of molecular sieves: pillared
acid clays using as starting material one natural montmorillonite clay and the synthesis of
zeolites from a silico-aluminous residue. This residue is a byproduct of the extraction of
lithium -spodumene. The preparation of pillared acid clays was performed in two steps: 1?
acid treatment of clay samples (time and temperature studies) and 2?pilarization of them with
Al13 (Keggin ion). The temperature and acid concentration affect the removal of cations in the
structure and porosity of the material obtained. The analysis of X-ray diffraction (XRD) and
infrared spectroscopy (IR), showed that increasing the severity of the acid treatment
compromises the structural material. Also the pore size distribution is approximately uniform.
Despite presenting a structural disorganization, the samples were pillared. As evidenced by
XRD increasing the basal spacing, specific area and uniform porosity by adsorption of N2.
Regarding the microporous molecular sieves were synthesized zeolites A and NaP1 from a
silico-aluminous residue, a byproduct of extracting lithium. The temperature and time of
agitation during the synthesis were the most important factors for obtaining zeolite A. The
aging of the gel and the highest crystallization time promoted the formation of zeolite NaP1
using a Si / Al ratio = 3.2 / Modifica??es estruturais de res?duos para s?ntese de ze?litas ? tema de muitos estudos
desenvolvidos na ?rea de s?ntese de peneiras moleculares. Estes materiais s?o chamados de
peneiras moleculares por possu?rem tamanho de poros bem definido e por terem a capacidade
de selecionar as mol?culas pelo tamanho. Neste trabalho foram estudados os processos de
s?ntese de dois tipos de peneiras moleculares: argilas ?cidas pilarizadas, utilizando como
mat?ria prima natural uma argila montmorilonita, e tamb?m a s?ntese de ze?litas a partir de
um res?duo s?lico-aluminoso subproduto da extra??o de L?tio do -espodum?nio. A
prepara??o de argilas ?cidas pilarizadas foi realizada em duas etapas: 1? tratamento ?cido das
amostras de argila (estudos de tempo e temperatura) e 2? pilariza??o das mesmas com Al13
(?on de keggin). As vari?veis temperatura e concentra??o do ?cido influenciaram na retirada
de c?tions estruturais e na porosidade do material obtido. A partir das an?lises de difra??o de
raios-X (DRX) e espectroscopia de infravermelho (IV), observou-se que o aumento da
severidade do tratamento ?cido compromete a organiza??o estrutural do material. Tamb?m a
distribui??o no tamanho de poros fica menos uniforme. Mesmo apresentando menor
organiza??o estrutural, as amostras foram pilarizadas. Foi comprovado por DRX o aumento
do espa?amento basal e por adsor??o de N2 o aumento da ?rea espec?fica e uniformiza??o dos
poros. Com rela??o ?s peneiras moleculares microporosas, foram sintetizadas ze?litas A e
NaP1 a partir de um res?duo s?lico-aluminoso, subproduto da extra??o de L?tio. A temperatura
e o tempo de agita??o durante o processo de s?ntese s?o par?metros importantes para a
obten??o da ze?lita A. O envelhecimento do gel e o maior tempo de cristaliza??o promoveram
a forma??o da ze?lita NaP1, utilizando uma rela??o Si/Al = 3,2
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Efeito da adi??o de feldspato e/ou res?duo de caulin em formula??es ? base de argila il?ticaCastro, Raimundo Jos? de Sousa 16 November 2010 (has links)
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Previous issue date: 2010-11-16 / The red pottery industry in Piau? state is well developed and stands out at the
national context for the technical quality of its products. The floor and wall tile
industry, however, is little developed since the state has only one company that
produces red clay-based ceramic tiles. This thesis aims at using the predominantly
illitic basic mass of the above mentioned industry, with the addition of feldspar and/or
kaolin residue in order to obtain products of higher technical quality. Kaolin residue
consists basically of kaolinite, muscovite mica and quartz; the feldspar used was
potassic. In this experiment, basic mass (MB) was used for experimental control and
fifteen formulations codified as follows: F2, F4, F8, F16, F32, FR2, FR4, FR8, FR16,
FR32, R2, R4, R8, R16 and R32. All raw materials were dry-milled, classified,
formulated and then humidified to 10% water. Thereafter, test samples were
produced by unixial pressing process in a rectangular steel matrix (60.0 x 20.0 x 5.0)
mm3 at (25 MPa). They were fired at four temperatures: 1080?C, 1120?C, 1160?C,
with a heating rate of 10?C/min during up to 10 min in an electric oven, and the last
one in an industrial oven with a peak of 1140?C, aim ing to confirm the results found
in laboratory and, finally, technological tests were performed: MEA, RL, AA, PA, TRF
and PF. The results revealed that the residue under study can be considered a raw
material with large potential in the industry of red clay-based ceramic tiles, since the
results found both in laboratory and in the industry have shown that the test samples
produced from the formulations with up to 4% feldspar and those produced with up to
8% feldspar and residue permitted a reduction in the water absorption rate and an
increase in the mechanical resistance while those samples produced with up to 4%
residue had an increase in the mechanical resistance when compared to those
produced from the basic mass and that the formulation with 2% feldspar and residue
presented the best technological properties, lowering the sintering temperature down
to 1120?C / A ind?stria de cer?mica vermelha do Piau? ? bem desenvolvida e se destaca no
contexto nacional pela qualidade t?cnica de seus produtos. J? a ind?stria de
revestimento pouco se desenvolveu, visto que o estado possui uma ?nica empresa
que produz revestimento de base argilosa vermelha. Esta tese tem por objetivo
utilizar a massa b?sica predominantemente il?tica da ind?stria citada, adicionando ?
mesma feldspato e/ou res?duo de caulim com o prop?sito de obter produtos de
melhores qualidades t?cnicas. O res?duo caulim ? constitu?do basicamente de
caulinita, mica moscovita e quartzo; o feldspato utilizado foi o pot?ssico. Para este
experimento, utilizou-se a massa b?sica (MB) para controle experimental e quinze
formula??es assim codificadas: F2, F4, F8, F16, F32, FR2, FR4, FR8, FR16, FR32,
R2, R4, R8, R16 e R32. Todas as mat?rias-primas foram mo?das a seco,
caracterizadas, formuladas, depois umidificadas a 10% com ?gua. Em seguida,
foram confeccionados corpos-de-prova por prensagem uniaxial em matriz retangular
de a?o (60,0 x 20,0 x 5,0) mm? a (24 MPa), os quais foram queimados em quatro
temperaturas: 1080?C, 1120?C, 1160?C, com taxa de aqu ecimento de 10?C/min e
patamar de 10 min em forno el?trico, e a ?ltima em forno a rolo industrial e pico de
1140?C com o objetivo de validar os resultados encontra dos em laborat?rio; por
?ltimo, foram realizados ensaios tecnol?gicos: MEA, RL, AA, PA, TRF e PF. Os
mesmos mostraram que o res?duo estudado pode ser considerado como mat?riaprima
de grande potencial para a ind?stria de pisos e revestimentos cer?micos de
base argilosa vermelha, j? que tanto os resultados encontrados em laborat?rio como
na ind?stria mostram que os corpos-de-prova produzidos a partir das formula??es
com feldspato at? 4% e os produzidos com feldspato e res?duo at? 8% permitiram
uma redu??o da absor??o de ?gua e aumento da resist?ncia mec?nica, sendo que
os corpos-de-prova produzidos com at? 4% de res?duo tiveram aumento da
resist?ncia mec?nica, quando comparados aos corpos-de-prova produzidos a partir
da massa b?sica e que a formula??o com 2% de feldspato e res?duo apresentou
melhores propriedades tecnol?gicas, reduzindo a temperatura de sinteriza??o para
1120?C
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Adi??o de res?duo cer?mico em pastas geopolim?ricas para cimenta??o de po?os de petr?leoPinto, Erica Natasche de Medeiros Gurgel 01 June 2011 (has links)
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Previous issue date: 2011-06-01 / The development of activities the of oil and gas sector have promoted the search for
suitable materials for cementing oil wells. In the state of the Rio Grande do Norte, the
integrity of the cement sheath tends to be impaired during steam injection, a
procedure necessary to increase oil recovery in reservoirs with low-viscosity oil. The
geopolymer is a material that can be used as alternative cement, since it has been
used in the production of fire-resistant components, building structures, and for the
control of toxic or radioactive residues. Geopolymers result from condensation
polymer alkali aluminosilicates and silicates resulting three-dimensional polymeric
structures. They are produced in a manner different from that of Portland cement,
which is made an activating solution that is mixed with geopolymer precursor. Among
the few works studied allowed us to conclude that the pastes prepared with
metakaolin as precursor showed better performance of its properties. Several studies
show the addition of waste clay as a means of reducing cost and improving end of
the folder properties. On this basis, the goal is to study the influence of the addition of
ceramic waste in geopolymer paste. To develop the study of rheology tests were
carried out, filtered, thickening time, compressive strength, free water, specific gravity
and permeability, according to the American Pretoleum Institute (API). The results for
all formulations studied show that the folders have high mechanical strength to a light
paste; low filtrate volume, absence of free water, very low permeability, slurry,
consistent with a light paste, and thickening time low that can be corrected with the
use of a retardant handle. For morphological characterization, microstructural,
physical, chemical and thermal tests were carried out by XRD, MEV, DTA, TG, FTIR.
In the trial of XRD, it was found that geopolymer is an amorphous material, with a
peak of crystalline kaolinite. In tests of TG / DTA, revealed the presence of a
significant event, which represents the mass loss related to water, and also observed
the reduction of weight loss by increasing the concentration of ceramic waste. In the
trial of MEV, we found a uniform matrix without the presence of other phases. In the
trial of FT-IR, we observed the presence of the band related to water. From all results
it was determined that the optimum concentration range of use is between 2.5 and
5% of waste ceramic / O desenvolvimento das atividades do setor de petr?leo e g?s tem promovido a
busca de materiais mais adequados para cimenta??o de po?os de petr?leo. No
estado do RN, a integridade da bainha cimentante tende a ser prejudicada durante a
inje??o de vapor, procedimento necess?rio para aumentar a recupera??o do
petr?leo em reservat?rios com ?leo de alta viscosidade. O geopol?mero ? um
material que pode ser utilizado como cimento alternativo, uma vez que vem sendo
empregado na produ??o de componentes resistentes ao fogo, na constru??o de
estruturas, e para o controle de res?duos t?xicos ou radioativos. Geopol?meros
resultam da condensa??o polim?rica de aluminosilicatos e silicatos alcalinos
originando estruturas polim?ricas tridimensionais. S?o produzidos de uma maneira
distinta daquela do cimento Portland, onde ? feita uma solu??o ativadora que ?
misturada ao precurssor geopolim?rico. Dentre os trabalhos estudados, alguns
permitiram-nos concluir que as pastas preparadas com metacaulim como precursor
apresentaram melhor desempenho de suas propriedades. V?rios estudos
apresentam a adi??o de res?duos argilosos como forma de redu??o do custo final e
melhoria das propriedades da pasta. Com base nisso, o objetivo do trabalho ?
estudar a influ?ncia da adi??o de rejeito cer?mico em pastas geopolim?ricas. Para o
desenvolvimento do estudo foram realizados testes de reologia, filtrado, tempo de
espessamento, resist?ncia ? compress?o, ?gua livre, peso espec?fico e
permeabilidade, de acordo com o American Pretoleum Institute (API). Os resultados
encontrados para todas as formula??es demonstram que as pastas estudadas
apresentam resist?ncia mec?nica elevada para uma pasta leve; volume de filtrado
baixo; aus?ncia de ?gua livre; permeabilidade muito baixa; pasta flu?da, coerente
com uma pasta leve; e tempo de espessamento baixo, que pode ser corrigido com a
utiliza??o de um retardador de pega. Para caracteriza??o morfol?gica,
microestrutural, f?sico-qu?mica, qu?mica e t?rmica, foram realizadas caracteriza??es
por DRX, MEV, DTA, TG, FT-IR. No ensaio de DRX, verificou-se que o geopol?mero
? um material amorfo, com um pico cristalino de caulinita. Nos testes de TG/DTA, foi
observado a presen?a de um evento significativo, que representa a perda de massa
referente a ?gua, sendo observado tamb?m a redu??o da perda de massa com o
aumento da concentra??o de rejeito cer?mico. No ensaio de MEV, encontrou-se
uma matriz uniforme e nos espectros de FT-IR, observou-se a presen?a da banda
referente ? ?gua. A partir de todos os resultados foi poss?vel determinar que a faixa
de concentra??o ?tima de rejeito cer?mico para uso em pastas geopolim?ricas ?
entre 2,5 e 5 %
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Estudo de massa cer?mica triaxial visando ? otimiza??o do ciclo de queima da ind?stria de cer?mica estruturalSales J?nior, Jos? Carlos Calado 31 May 2012 (has links)
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Previous issue date: 2012-05-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Over recent years the structural ceramics industry in Brazil has found a very favorable market for growth. However, difficulties related to productivity and product quality are partially inhibiting this possible growth. An alternative for trying to solve these problems and, thus, provide the pottery industry the feasibility of full development, is the substitution of firewood used in the burning process by natural gas. In order to contribute to this process of technological innovation, this paper studies the effect of co-use of ceramic phyllite and kaolin waste on the properties of a clay matrix, verifying the possible benefits that these raw materials can give to the final product, as well as the possibility of such materials to reduce the heat load necessary to obtain products with equal or superior quality. The study was divided into two steps: characterization of materials and study of formulations. Two clays, a phyllite and a residue of kaolin were characterized by the following techniques: laser granulometry, plasticity index by Atterberg limits, X-ray fluorescence, X-ray diffraction, mineralogical composition by Rietveld, thermogravimetric and differential thermal analysis. To study the formulations, specifically for evaluation of technological properties of the parts, was performed an experimental model that combined planning involving a mixture of three components (standard mass x phyllite x kaolin waste) and a 23 factorial design with central point associated with thermal processing parameters. The experiment was performed with restricted strip-plot randomization. In total, 13 compositional points were investigated within the following constraints: phyllite ≤ 20% by weight, kaolin waste ≤ 40% by weight, and standard mass ≥ 60% by weight. The thermal parameters were used at the following levels: 750 and 950 ?C to the firing temperature, 5 and 15 ?C/min at the heating rate, 15 and 45min to the baseline. The results showed that the introduction of phyllite and/or kaolin waste in ceramic body produced a number of benefits in properties of the final product, such as: decreased absorption of water, apparent porosity and linear retraction at burn; besides the increase in apparent specific mass and mechanical properties of parts. The best results were obtained in the compositional points where the sum of the levels of kaolin waste and phyllite was maximal (40% by weight), as well as conditions which were used in firing temperatures of 950 ?C. Regarding the prospect of savings in heat energy required to form the desired microstructure, the phyllite and the residue of kaolin, for having small particle sizes and constitutions mineralogical phases with the presence of fluxes, contributed to the optimization of the firing cycle. / Ao longo dos ?ltimos anos a ind?stria de cer?mica estrutural no Brasil vem encontrando um mercado bastante favor?vel para o crescimento. Entretanto dificuldades relacionadas ? produtividade e qualidade dos produtos est?o inibindo parcialmente esse poss?vel crescimento. Uma das alternativas para tentar solucionar esses problemas e, consequentemente, proporcionar ao setor oleiro a viabilidade do pleno desenvolvimento, ? a substitui??o da lenha utilizada no processo de queima pelo g?s natural. Com o intuito de contribuir nesse processo de inova??o tecnol?gica, o presente trabalho trata-se de um estudo do efeito da co-utiliza??o de filito cer?mico e res?duo de caulim sobre as propriedades de uma matriz argilosa, verificando os poss?veis benef?cios que esses materiais podem atribuir ao produto final, bem como, a possibilidade dessas mat?rias-primas reduzirem a carga t?rmica necess?ria para obten??o de produtos de igual ou superior qualidade. O trabalho foi divido em duas etapas: caracteriza??o dos materiais e estudo das formula??es. Duas argilas, um filito e um res?duo de caulim foram caracterizados atrav?s das seguintes t?cnicas: granulometria ? laser, ?ndice de plasticidade pelos limites Atterberg, fluoresc?ncia de raios X, difra??o de raios X, composi??o mineral?gica por Rietveld, an?lise termogravim?trica e an?lise t?rmica diferencial. Para o estudo das formula??es, mais especificamente para avalia??o das propriedades tecnol?gicas das pe?as, foi executado um modelo experimental que combinou um planejamento envolvendo mistura de tr?s componentes (massa padr?o x filito x res?duo de caulim) e um planejamento fatorial 23 com ponto central associado aos par?metros t?rmicos de processamento. A experimenta??o foi realizada com restri??o na aleatoriza??o por strip-plot. No total foram investigados 13 pontos composicionais dentro das seguintes restri??es: filito ≤ 20% em peso; res?duo de caulim ≤ 40% em peso; e massa padr?o ≥ 60% em peso. Os par?metros t?rmicos foram utilizados nos seguintes n?veis: 750 e 950 ?C para temperatura de queima; 5 e 15 ?C/min para a taxa de aquecimento; 15 e 45 min para o patamar. Os resultados obtidos demostraram que a introdu??o do filito e/ou res?duo de caulim na massa cer?mica produz uma s?rie de benef?cios nas propriedades do produto final, tais como: redu??o na absor??o de ?gua, porosidade aparente e retra??o linear de queima; al?m do aumento na massa espec?fica aparente e na resist?ncia mec?nica das pe?as. Os melhores resultados foram obtidos nos pontos composicionais em que a soma dos teores de filito e res?duo de caulim foi m?xima (40 % em peso), assim como, nas condi??es de queima em que foram utilizadas temperaturas de 950 ?C. Em rela??o ? perspectiva de economia na energia t?rmica necess?ria para forma??o da microestrutura desej?vel, o filito e o res?duo de caulim por apresentarem pequenos tamanhos de part?culas e constitui??es mineral?gicas com presen?a de fases fundentes, contribu?ram para a otimiza??o do ciclo de queima.
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Estudo da adi??o de res?duo de scheelita em matriz cer?mica: formula??o, propriedades f?sicas e microestrutura / Study of the addition of residue of scheelite in ceramic matrix: formulation, physical properties and microstructureMachado, Tercio Graciano 23 November 2012 (has links)
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Previous issue date: 2012-11-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Extractivism mineral is considered an activity highly degrading, due to the large volume of
material that he moves in the form of ore and residues. The vast majority of mining
companies do not show any technology or economically viable application that will allow the
recycling of mineral residue, these being launched in areas receiving located the "open skies"
degrade the environment. In Rio Grande do Norte to the production of ceramic red restricts
their activities to the production of products such as: solid bricks, ceramic blocks, tiles,
among others. Seeking to unite experiences and technical information that favor sustainable
development, with important benefits to the construction sector and civil society in general,
the present work studies the incorporation of the residue of scheelite in ceramic matrix
kaolinitic, coming from the municipality of Boa Sa?de - RN, in percentage of 5 %, 10 %,
20 %, 30% 40% and 50 %, by evaluating its microstructure, physical properties and
formulation. The raw materials were characterized through the trials of X ray fluorescence,
Diffraction of X rays, Differential Thermal Analysis and Termogravimetric Analysis. The
samples were formed and fired at temperatures of 850o, 900o, 1000o, 1050o, 1100o, 1150o and
1200 oC, with isotherm of 1 hour and heating rate of 10 oC/min. Assays were performed
technological of loss to fire, Water Absorption, Apparent Porosity, Apparent Density, Mass
Loss in Fire and Bending Resistance; in addition to the Scanning Electron Microscopy,
analyzing their physical and mechanical properties. The use of residue of scheelite in ceramic
mass kaolinitic provided a final product with technological properties that meet the technical
standards for the production of bricks and roofing tiles, with the percentage of 20% of waste
that showed the best results / O extrativismo mineral ? considerado uma atividade altamente degradante, devido ao grande
volume de material que ele movimenta em forma de min?rio e res?duo. A grande maioria das
empresas mineradoras n?o apresenta nenhuma tecnologia ou aplica??o economicamente
vi?vel que permitam a reciclagem do res?duo mineral, sendo estes lan?ados em ?reas de
recebimento localizadas a c?u aberto , degradando o meio ambiente. No Rio Grande do
Norte a produ??o de cer?mica vermelha restringe suas atividades ? produ??o de produtos
como: tijolos maci?os, blocos cer?micos, telhas, dentre outros. Buscando unir experi?ncias e
informa??es t?cnicas que favore?am o desenvolvimento sustent?vel, com importantes
benef?cios ao setor da Constru??o Civil e ? sociedade em geral, o presente trabalho estuda a
incorpora??o do res?duo de scheelita em matriz cer?mica caulin?tica, proveniente do
munic?pio de Boa Sa?de RN, em percentuais de 5%, 10%, 20%, 30% 40% e 50%, avaliando
sua microestrutura, propriedades f?sicas e formula??o. As mat?rias-primas foram
caracterizadas atrav?s dos ensaios de Fluoresc?ncia de raios X, Difra??o de raios X, An?lise
T?rmica Diferencial e An?lise Termogravim?trica. Os corpos de prova foram conformados e
queimados nas temperaturas de 850o, 900o, 1000o, 1050o, 1100o, 1150o e 1200 oC, com
isoterma de 1 hora e taxa de aquecimento de 10 oC/min. Foram realizados os ensaios
tecnol?gicos de Perda ao Fogo, Absor??o de ?gua, Porosidade Aparente, Massa Espec?fica
Aparente e Tens?o de Ruptura ? Flex?o; al?m da Microscopia Eletr?nica de Varredura,
analisando-se suas propriedades f?sicas e mec?nicas. A utiliza??o de res?duo de scheelita em
massa cer?mica caulin?tica propiciou um produto final com propriedades tecnol?gicas que
atendem as normas t?cnicas para produ??o de blocos e telhas cer?micas, sendo que o
percentual de 20% de res?duo apresentou os melhores resultados
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Estudo da potencialidade da incorpora??o de res?duo de granito e da queima da casca do caf? em cer?mica vermelhaAvelino, Keite Anny Rocha 29 November 2013 (has links)
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Previous issue date: 2013-11-29 / The industrial production of ornamental rocks and the burning of coffee husk generate waste that is discarded into the environment. However, with the study of the incorporation of these residues in ceramic products, may be found an alternative to reducing environmental impacts and detrimental effects on human health caused by its indiscriminate disposal of waste in nature. Thus, this work aimed to study the addition of ashes of the coffee husk and granite residue in matrix of red ceramic. The raw materials were dry milled and sieved to mesh 100. To characterize the raw materials were carried out analyzes of X-ray diffraction (XRD), X-ray fluorescence (XRF), particle size analysis (PSA), differential thermal analysis (DTA) and thermogravimetric analysis (TG). Six formulations were prepared where the clay content was kept constant (70%wt) and ashes contents and granite residue varied from 10, 15, 20 and 30%. Dilatometrics analyzes were performed at four selected formulations, containing them: 100% clay (A100); 70% clay and 30% ashes (A70C30); 70% clay and 30% granite residue (A70G30); and 70% clay, 15% granite residue and 15% ashes (A70G15C15). The samples were prepared by uniaxial compaction with pressure of 25 MPa, and fired at temperatures of 800?C, 850?C, 900?C, 950?C, 1000?C and 1100?C. Assays were performed to determine the linear shrinkage of burning (LSB), water absorption (WA), apparent porosity (AP), density (D) and tensile bending. Also were performed analyzes of X-ray diffraction (XRD) and scanning electron microscopy (SEM) of the samples fired. The formulations incorporating granite residue and/or ashes reached the required limits of water absorption according to NBR 15270-1 and NBR 15310 and tensile bending according to classical literature (SANTOS, 1989) necessary for the production of tiles and ceramic block for masonry sealing / A produ??o industrial de rochas ornamentais e a queima da casca do caf? geram res?duos que s?o descartados no meio ambiente. Por?m, com o estudo da incorpora??o destes res?duos em produtos cer?micos, poder? ser encontrada uma alternativa para a redu??o dos impactos ambientais e efeitos danosos ? sa?de humana causados pelo seu descarte indiscriminado na natureza. Nesse sentido, este trabalho teve como objetivo estudar a adi??o de cinzas da casca do caf? e res?duo de granito na argila usada para a produ??o de cer?mica vermelha. As mat?rias-primas foram mo?das a seco e peneiradas na malha 100 mesh. Para caracterizar as mat?rias-primas foram realizadas as an?lises de difra??o de raios X (DRX), fluoresc?ncia de raios X (FRX), an?lise granulom?trica (AG), an?lise t?rmica diferencial (DTA) e an?lise termogravim?trica (TG). Foram preparadas seis formula??es onde o teor de argila foi mantido constante (70% em peso) e os teores de cinzas e de res?duo de granito variaram de 10, 15, 20 e 30%. Foram realizadas an?lises dilatom?tricas em quatro formula??es selecionadas, contendo elas: 100% argila (A100); 70% argila e 30% cinza (A70C30); 70% argila e 30% res?duo de granito (A70G30); e 70% argila, 15% res?duo de granito e 15% cinza (A70G15C15). As amostras foram confeccionadas por compacta??o uniaxial com press?o de 25 MPa, e queimadas ?s temperaturas de 800?C, 850?C, 900?C, 950?C, 1000?C e 1100?C. Foram realizados ensaios para determinar a retra??o linear de queima (RLq), absor??o de ?gua (AA), porosidade aparente (PA), massa espec?fica aparente (MEA) e tens?o de ruptura ? flex?o (TRF). Foram realizadas tamb?m an?lises de difra??o de raios X (DRX) e microscopia eletr?nica de varredura (MEV) das amostras queimadas. As formula??es com incorpora??o de res?duo de granito e/ou cinza alcan?aram os limites exigidos de absor??o de ?gua segundo as normas NBR 15270-1 e 15310 e de tens?o de ruptura ? flex?o segundo a literatura cl?ssica (SANTOS, 1989), necess?rios para a produ??o de telhas e blocos cer?micos para alvenaria de veda??o
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