Made available in DSpace on 2014-12-17T14:06:46Z (GMT). No. of bitstreams: 1 RobertoALS.pdf: 742174 bytes, checksum: d1b0bdbe4af3f236ae47837eb186d487 (MD5) Previous issue date: 2008-03-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / There are ores of clay in Piau? State that are used for red structural ceramics, which are naturally contaminated with calcareous vein. This is one thing that impedes its exploration in an adequate way, especially for tile production. The present work aims at verifying the influence of the calcareous contents in the technological structural ceramics area, seeking to determine a maximum permissible calcareous proportion/contents in the ceramic mass using the patterns of the local industry production. For the consecution of this paper, it was characterized the clay and calcareous material by FRX, DRX, TGA and DTA. It was also configurated by extrusion and burnt in the temperatures of 850?C, 900?C, 950?C and 1000?C pieces of the corpus with 0, 5, 10, 15 e 20% of calcareous proportion. After that, it was carried out technological samples of linear retraction, water absortion, apparent porosity, specific apparent mass and mechanic resistance. The results showed the possibility of using calcareous in the ceramic mass and in some cases the technological properties got better / O estado do Piau? tem jazidas de argilas utilizadas para cer?mica vermelha estrutural, que naturalmente est?o contaminadas com veios de calc?rio, o que impede a sua explora??o de forma adequada, principalmente para a produ??o de telhas. O presente trabalho tem o objetivo de verificar a influ?ncia do teor de calc?rio nas propriedades tecnol?gicas da cer?mica estrutural, visando definir um teor m?ximo de calc?rio admiss?vel na massa cer?mica utilizando-se dos padr?es de produ??o da ind?stria local. Para isso, foram caracterizadas as mat?rias-primas argila e calc?rio por FRX, DRX, TGA e DTA. Tamb?m foram conformados por extrus?o e queimados nas temperaturas de 850?C, 900?C, 950?C e 1000?C corpos-de-prova com 0%, 5%, 10%, 15% e 20% de teor de calc?rio, em seguida, realizados ensaios tecnol?gicos de retra??o linear, absor??o de ?gua, porosidade aparente, massa espec?fica aparente e resist?ncia mec?nica ? flex?o. Os resultados mostraram a possibilidade de se utilizar calc?rio na massa cer?mica, sendo que em alguns casos melhorou as propriedades tecnol?gicas

Made available in DSpace on 2014-12-17T14:06:47Z (GMT). No. of bitstreams: 1 JulianaEOS.pdf: 524673 bytes, checksum: ccc9d30caaf92e00eb51bdb45afef210 (MD5) Previous issue date: 2007-11-23 / The Industry of the Civil Construction has been one of the sectors that most contribute to the pollution of the environment, due to the great amount of residues generated by the construction, demolition and the extraction of raw material. As a way of minimizing the environmental impacts generated by this industry, some governmental organizations have elaborated laws and measures about the disposal of residues from the building construction (CONAMA - resolution 307). This work has as objective the reutilization of residues compound of sand, concrete, cement, red bricks and blocks of cement and mortar for the production of red ceramic, with the objective of minimizing costs and environmental impacts. The investigated samples contained 0% to 50% of residues in weight, and they were sintered at temperatures of 950?C, 1000?C, 1050?C, 1100?C and 1150?C. After the sinterization, the samples were submitted to tests of absorption of water, linear retraction, resistance to bending, apparent porosity, specific density, XRD and SEM. Satisfactory results were obtained in all studied compositions, with the possible incorporation of up to 50% of residues in ceramic mass without great losses in the mechanical strength, giving better results to the incorporation of 30% of residues in the fabrication of ceramic parts, such as roofing tiles, bricks masonry and pierced bricks / A ind?stria da constru??o civil tem sido um dos setores que mais tem contribu?do com a polui??o do meio ambiente devido a grande quantidade de res?duos gerados pela constru??o, demoli??o e extra??o de mat?ria prima. Como forma de minimizar os impactos ambientais gerados, alguns ?rg?os governamentais tem elaborado leis e medidas sobre a disposi??o de res?duos da constru??o civil (CONAMA resolu??o 307). Este trabalho tem como objetivo estudar o reaproveitamento de res?duos da constru??o civil composto de areia, concreto, cimento, tijolos vermelhos, e blocos de cimento e argamassa na massa para fabrica??o de cer?mica vermelha, com o objetivo de minimizar custos e impactos ambientais gerados. As amostras investigadas continham 0% a 50% em peso de res?duo, sendo sinterizadas nas temperaturas de 950?C, 1000?C, 1050?C, 1100?C e 1150?C. Ap?s a sinteriza??o as amostras foram submetidas a ensaios de absor??o de ?gua, retra??o linear, resist?ncia ? flex?o, porosidade aparente, massa espec?fica, DRX e MEV. Foram obtidos resultados satisfat?rios em todas as composi??es estudadas, sendo poss?vel a incorpora??o de at? 50% de res?duo nas massas cer?micas sem grandes perdas na resist?ncia mec?nica, apresentando melhores resultados para a incorpora??o de 30% de res?duos na massa de fabrica??o de pe?as cer?micas como telhas, tijolos de alvenaria e furados

Made available in DSpace on 2014-12-17T14:06:49Z (GMT). No. of bitstreams: 1 VilsonRR.pdf: 664562 bytes, checksum: 2161eaac4d687b2ded4c5599d576cc33 (MD5) Previous issue date: 2008-06-13 / This research presents an outlook of the industries of red ceramic in the region next to the city of Teresina and an analysis of the ceramic products producted in this pole. The microregion investigated possesses 13 boroughs where were identified 32 ceramic in operation, being that 24 are located in Teresina, the ceramic region more important of Piau?, 1 is located in the city of Miguel Le?o and 7 is located in Timon city that belongs to the state of Maranh?o. The majority of ceramics are pulverized in these two cities, Teresina and Timon , responsible by a largely production independent of distance between fabric and consumer market. Furthermore, there is an artisanal production realized in other boroughs, mainly manual conformation bricks, where are producted diverse types of handicraft and ceramics utilitarian. The objective of this research is to evalue the conformity of ceramic blocks for brick of obstruction made by red ceramic industry of microregion at studying, verifying their pontentialities and adequacy in terms of production. In this research universe made a search of ceramic industries related to the Foundation CEPRO (Foundation Center of Research Social and Economic of Piau?). For the analysis of the ceramic products , were colected 60 crude bricks sample in three industries for their characterization, and 39 burned bricks sample for the Evaluation of Conformity. The results of the characterization made reached a accetptable standard in all formulations and temperature studied. The burned samples were applied to the geometric, physical and mechanical assays according to the ABNT standards (Brazilian Association of Technical Standards). The results of the physical assays showed that all the samples are at the same band recommended by standard. However, through the geometric assays just two industries did not present results according to the standard, due to lack of control in their process such as in their equipments. Taking into account the mechanical properties, only one industry investigated was not according to the standard / Esta pesquisa apresenta um panorama das ind?strias de cer?mica vermelha na Regi?o Integrada de Desenvolvimento da Grande Teresina e uma an?lise dos produtos cer?micos fabricados nesse p?lo. A microrregi?o em estudo possui 13 munic?pios onde foram identificadas 32 cer?micas em atividades, sendo que 24 est?o situadas na cidade de Teresina, o p?lo cer?mico de maior import?ncia do Piau?, 1 na cidade de Miguel Le?o e 7 no munic?pio de Timon, no vizinho estado do Maranh?o, que faz parte da grande Teresina. A maioria das cer?micas est? pulverizada nestas duas Cidades, Teresina e Timon, respons?veis por uma produ??o largamente independente da dist?ncia entre f?brica e mercado consumidor. Al?m dessas, h? a produ??o artesanal realizada nos demais munic?pios, principalmente, tijolos de conforma??o manual, onde tamb?m s?o produzidos diversos tipos de artesanato e utilit?rios cer?micos. O objetivo desta pesquisa ? avaliar a conformidade de blocos cer?micos para alvenaria de veda??o, produzidos pela ind?stria de cer?mica vermelha da microrregi?o em estudo, verificando suas potencialidades e adequa??o em termos produtivos. Para defini??o do universo da pesquisa, fez-se um levantamento das ind?strias cer?micas junto ? Funda??o CEPRO (Funda??o Centro de Pesquisas Econ?micas e Sociais do Piau?). Para a an?lise dos produtos cer?micos, foram coletadas 60 amostras de tijolos verdes em tr?s ind?strias, para a caracteriza??o desses produtos e 39 amostras de tijolos queimados, para a avalia??o da conformidade. Os resultados das caracteriza??es realizadas apresentaram um padr?o aceit?vel em todas as formula??es e temperaturas estudadas. As amostras queimadas foram submetidas aos ensaios geom?tricos, f?sicos e mec?nicos de acordo com as normas da ABNT (Associa??o Brasileira de Normas T?cnicas). Os resultados dos ensaios f?sicos mostraram que todas as amostras est?o dentro da faixa recomenda pela norma. J? nos ensaios geom?tricos, duas ind?strias apresentaram resultados n?o conforme com a norma, devido ? falta de controle nos seus processos e nos equipamentos. Quanto ?s propriedades mec?nicas, apenas uma ind?stria pesquisada n?o atendeu ? norma, devido ao fato do controle inadequado do seu processo

Made available in DSpace on 2014-12-17T14:06:49Z (GMT). No. of bitstreams: 1 FranciolliSDA.pdf: 2363369 bytes, checksum: 60110371e06857963dc0f1bfade49f3a (MD5) Previous issue date: 2008-08-05 / The WTP produce many kinds of residue on your treatment stages, but the sludge is the more problematic from the final disposition point view. The actual rate of residue production deriving from technological evolution and the crescent population needs prevents the subtle equilibrium generation between consumption and recycling/reuse, creating problems of pollution resulting from inappropriate management of residues. Thus, is necessary achieve a new equilibrium between the grow from raw materials and energy and the residue generation. This equilibrium should be achieved by technical and economic feasibility of environmental supported models through recycling and reuse. The red ceramic industry stand out in residue absorption question as raw material due their clay mass heterogeneity, constituted by clay minerals and non-clay minerals with wide mineralogical variation, allowing residue inclusion which act like plastic or non-plastic materials, contributing to retain heavy metals contained in residues in the vitreous mass formed during the burning of the ceramic bodies. This work propose the study of the influence of incorporation of 25 wt.% sludge from wastewater treatment plant, according preliminary results, in the mass to produce ceramic bodies. The raw materials was characterized through chemical composition analyses by XRF, mineralogical analyses by XRD, thermal analyses by TG and DTA, Atterberg limits and thermodilatometry. Subsequently was composed the mass with 75 wt.% of clay and 25 wt.% of dried wastewater sludge from UFRN WWTP. Samples with 6,0 x 2,0 x 0,5 cm was produced with unidirectional compacting under pressure of 20MPa and burned in temperatures between 950 and 1,200?C. After fired, the ceramic bodies have been submitted to physical and mechanical analyses through the measure of firing shrinkage, water absorption, density, apparent porosity and flexural strength; crystallographic analyses through XRD and microstructure analyses by SEM. The technological properties obtained was satisfactory to production of roof tiles with 25 wt.% at 1,200 ?C, but the production of others products at lower temperatures was not feasible / As ETE produzem v?rios tipos de res?duos em suas etapas de tratamento, mas o lodo ? o res?duo mais problem?tico do ponto de vista de disposi??o final. A atual taxa de gera??o de res?duos, acarretada da evolu??o tecnol?gica e da crescente demanda populacional, impede a gera??o de um equil?brio h?bil entre o consumo e a reciclagem/reuso, gerando problemas de polui??o resultantes da gest?o inadequada dos res?duos. Dessa forma, ? necess?rio atingir um novo equil?brio entre o crescimento das demandas por mat?rias e energia e a gera??o de res?duos. Este equil?brio, s? pode ser alcan?ado atrav?s da viabiliza??o t?cnica e econ?mica de modelos de sustentabilidade ambiental, atrav?s da reciclagem e do reuso. A ind?stria de cer?mica vermelha se destaca no quesito absor??o de res?duos como mat?ria-prima em virtude da heterogeneidade das massas argilosas, constitu?das de argilominerais e minerais n?o argilosos com ampla varia??o mineral?gica, permitindo a inclus?o de res?duos que atuem como plastificantes ou desplastificantes, e contribuindo tamb?m para a reten??o de metais pesados presentes nos res?duos na massa v?trea formada nos corpos cer?micos. Este trabalho prop?e estudar a influ?ncia da incorpora??o de 25% de lodo de esta??o de tratamento de esgoto, baseado em resultados preliminares, ? massa para produ??o de corpos cer?micos. As mat?rias-primas foram caracterizadas atrav?s de an?lise da composi??o qu?mica por FRX, an?lise mineral?gica por DRX, an?lise t?rmica por TG e DTA, an?lise dos limites de Atterberg e an?lise dilatom?trica. Em seguida foi composta a massa com 75% de argila e 25% em peso de lodo da ETE UFRN. Foram prensados corpos-de-prova com dimens?es 6,0 x 2,0 x 0,5 cm atrav?s de prensagem uniaxial sob press?o de 20MPa e queimadas nas temperaturas entre 950 e 1200?C. Ap?s a sinteriza??o, os corpos-de-prova foram submetidos a ensaios f?sico-mec?nicos atrav?s de medida de retra??o linear, absor??o de ?gua, massa espec?fica aparente, porosidade aparente e tens?o de ruptura ? flex?o; an?lise cristalogr?fica atrav?s de DRX e an?lise microestrutural atrav?s de MEV. As propriedades tecnol?gicas obtidas mostraram-se satisfat?rias para fabrica??o de telhas com 25% de lodo na temperatura de queima de 1.200 ?C, n?o sendo vi?vel a fabrica??o de outros produtos em temperaturas inferiores

Made available in DSpace on 2014-12-17T14:07:06Z (GMT). No. of bitstreams: 1 VilsonRR_TESE.pdf: 4774332 bytes, checksum: b653e020c564d2ea65edb56c41828fda (MD5) Previous issue date: 2010-09-21 / This research presents an overview of the addition steelwork dust of ceramic shingles in order to contribute to the utilization use of such residue. The ceramic industry perspective in the Brazilian State of Piau? is quite promising. Unlike other productive sectors, the ceramic industry uses basically natural raw materials. Its final products are, in short, the result of transforming clay compounds. These raw materials are composed primarily of aluminum oxide, silicon, iron, sodium, magnesium, end calcium, among others. It was verified that steelwork dust is composed primarily of these same oxides, so that its incorporation in to structural ceramics is a very reasonable idea. Both clay and steelwork powder were characterized by AG, XRF, XRD, TGA and DTA. In addition, steelwork dust samples containing (0%, 5%, 10%, 15%, 20% and 25%) were extruded and burned at 800?C, 850?C, 900?C and 950?C. Then t echnological tests of linear shrinkage, water uptake, apparent porosity, apparent density and flexural strengthwere carried at. The results showed the possibility of using steelwork powder in ceramic shingles until 15% significant improvement in physical and mechanical properties. This behavior shows the possibility of burning at temperatures lower than 850?C, thus promoting a product final cost reduction / Neste trabalho ? estudado o efeito da adi??o da esc?ria de aciaria em massas cer?micas para ind?strias de cer?mica vermelha, visando contribuir com o aproveitamento desses rejeitos. Foi feito uma avalia??o da sua adi??o ? massa cer?mica para produ??o de telhas. O panorama da ind?stria cer?mica no estado do Piau? ? bastante promissor. Diferente de outros setores produtivos, o setor cer?mico utiliza, basicamente, mat?rias-primas naturais. O seu produto final ?, em suma, o resultado da transforma??o de compostos argilominerais. Essas mat?rias-primas s?o compostas, basicamente, de ?xidos de alum?nio, sil?cio, ferro, s?dio, magn?sio, c?lcio, dentre outros. Verificou-se que a esc?ria de aciaria ? composta principalmente por esses mesmos ?xidos, de forma que sua incorpora??o ? massa de cer?mica estrutural ? uma ideia absolutamente razo?vel. Foram caracterizadas as mat?rias-primas argila e esc?ria de aciaria por AG, FRX, DRX, TGA e DTA. Tamb?m foram conformados por extrus?o e queimados nas temperaturas de 800?C, 850 ?C, 900?C e 950?C corpos-deprova com 0%, 5%, 10%, 15%, 20% e 25% de teor de esc?ria de aciaria. Em seguida, foram realizados ensaios tecnol?gicos de retra??o linear, absor??o de ?gua, porosidade aparente, massa espec?fica aparente e resist?ncia mec?nica ? flex?o. Os resultados mostraram a possibilidade de se utilizar at? 15% de esc?ria de aciaria na massa cer?mica para telhas. At? essa dosagem, melhorias consider?veis nas caracter?sticas f?sicas e mec?nicas avaliadas foram observadas. O estudo tamb?m mostrou a possibilidade de queima em temperaturas mais baixas que 850?C, promovendo, assim, uma redu??o dos custos finais do produto

Made available in DSpace on 2014-12-17T14:07:16Z (GMT). No. of bitstreams: 1 EleniseBBA_TESE.pdf: 3505529 bytes, checksum: 6fbefc3f97e2fee0bbc0545b60e3c26e (MD5) Previous issue date: 2013-07-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The power industry generates as waste ceramic bodies of electrical fuses that are discarded after use. The formulation of ceramic bodies for porcelain electrical insulators using waste from the bodies fuse allocation promotes environmentally appropriate, through the reuse of the material. This work evaluated the technical feasibility of using waste for use in electrical porcelains with formulations containing the residue, feldspar and kaolinite. The raw materials were processed through grinding and sieving to 200 mesh. The ceramic material obtained from the proposed formulations with 25%, 30%, 34% and 40% of the residue went through a vibratory mill for grinding and homogenization, and then were sieved at 325 mesh. The samples were shaped in a uniaxial press, with the application of 25 MPa and sintered at 1100? C, 1150?C, 1200?C, 1225?C and 1250?C, at levels of 20 and 45 minutes. Were also developed bodies of evidence with reference formulations obtained without residue, to establish a comparison on physical, mechanical and electrical. The tests were conducted and technology: linear shrinkage, porosity, water absorption, resistance to bending to three points, measuring insulation resistance electrical resistivity of the material, X-ray diffraction and X-ray fluorescence Waste characterizations pointed to the existence of two phases: mullite and quartz phases are of great importance in the microstructure of the ceramic and this fact reveals a possibility for reuse in electrical porcelains. The mullite is an important constituent because it is a phase that makes it possible to increase the mechanical strength in addition to the body allows the use at high temperatures. The use of ceramic bodies residue fuses, proved feasible for application in electrical porcelain and the most significant results were obtained by the formulations with 25% waste and sintering at 1200?C / O setor el?trico gera como res?duo os corpos cer?micos de fus?veis el?tricos que s?o descartados ap?s o uso. A formula??o de massas cer?micas para porcelanas el?tricas utilizando res?duos oriundos de corpos de fus?veis promove uma destina??o ambiental adequada, por meio do reaproveitamento do material. Neste trabalho foi avaliada a viabilidade t?cnica da utiliza??o do res?duo para a aplica??o em porcelanas el?tricas com formula??es contendo o res?duo, feldspato e argila caulin?tica. As mat?rias primas foram processadas passando por moagem e peneiramento a 200 Mesh. As massas cer?micas obtidas a partir das formula??es propostas com 25%, 30%, 34% e 40% do res?duo passaram por um moinho vibrat?rio para homogeneiza??o e moagem e depois foram peneiradas a 325 Mesh. Os corpos de prova foram conformados em uma prensa uniaxial, com aplica??o de 25 Mpa e sinterizados a 1100?C, 1150?C, 1200?C, 1225?C e 1250?C, com patamares de 20 e 45 minutos. Foram desenvolvidos tamb?m corpos de provas com formula??es de refer?ncia obtidas sem o res?duo, para estabelecer um comparativo na caracteriza??o f?sica, mec?nica e el?trica. Os ensaios e tecnol?gicos realizados foram: retra??o linear, porosidade, absor??o de ?gua, resist?ncia a flex?o a tr?s pontos, medi??o de resist?ncia de isola??o el?trica, resistividade do material, difra??o de raios X e fluoresc?ncia de raios X. A caracteriza??o do res?duo apontou para a exist?ncia de duas fases: mulita e quartzo, que s?o fases de grande import?ncia na microestrutura do material cer?mico e esse fato revela uma possibilidade para o reaproveitamento em porcelanas el?tricas. A mulita ? um importante constituinte pois ? uma fase que possibilita a eleva??o da resist?ncia mec?nica al?m de permite a utiliza??o do corpo em elevadas temperaturas. O uso do res?duo cer?micos dos corpos de fus?veis, se mostrou vi?vel para a aplica??o em porcelanas el?tricas e os resultados mais significativos foram obtidos pelas formula??es com 25% de res?duo e sinteriza??o a 1200?C

Made available in DSpace on 2014-12-17T14:07:22Z (GMT). No. of bitstreams: 1 RicardoPSD.pdf: 1922919 bytes, checksum: 54dfc0d5fe53e83de5babd021bd83da6 (MD5) Previous issue date: 2007-03-01 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Heating rate is one of the main variables that determine a fire cycle. In industrial processes that use high temperatures, greater fire great can reduce the cost of production and increase productivity. The use of faster and more efficient fire cycles has been little investigated by the structural ceramic industry in Brazil. However, one of the possibilities that aims at modernizing the sector is the use of roller kilns and the inclusion of natural gas as fuel. Thus, the purpose of this study is to investigate the effect of heating rate on the technological properties of structural ceramic products. Clay raw materials from the main ceramic industries in the state of Rio Grande do Norte were characterized. Some of the raw materials characterized were formulated to obtain the best physical and mechanical properties. Next, raw materials and formulations were selected to study the influence of heating rate on the final properties of the ceramic materials. The samples were shaped by pressing and extrusion and submitted to rates of 1 ?C/min, 10 ?C/min and 20 ?C/min, with final temperatures of 850 ?C, 950 ?C and 1050 ?C. Discontinuous cycles with rates of 10 ?C/min or 15 ?C/min up to 600 ?C and a rate of 20 ?C/min up to final temperature were also investigated. Technological properties were determined for all the samples and microstructural analysis was carried out under a number of fire conditions. Results indicate that faster and more efficient fire cycles than those currently in practice could be used, limiting only some clay doughs to certain fire conditions. The best results were obtained for the samples submitted to slow cycles up to 600 ?C and fast fire sinterization up to 950 ?C. This paper presents for the first time the use of a fast fire rate for raw materials and clay formulations and seeks to determine ideal dough and processing conditions for using shorter fire times, thus enabling the use of roller kilns and natural gas in structural ceramic industries / A taxa de aquecimento ? uma das principais vari?veis que determinam um ciclo de queima. Em processos industriais que utilizam elevadas temperaturas, uma maior velocidade de queima pode proporcionar uma diminui??o do custo de produ??o e aumento da produtividade. A ind?stria de cer?mica estrutural pouco tem investigado sobre a utiliza??o de ciclos de queima mais r?pidos e eficientes. Entretanto, uma das possibilidades que visam ? moderniza??o do setor ? a utiliza??o de fornos a rolos e a inclus?o do g?s natural como combust?vel. Neste contexto, o objetivo deste trabalho ? investigar o efeito da velocidade de aquecimento nas propriedades tecnol?gicas de produtos para cer?mica estrutural. Foram caracterizadas mat?riasprimas argilosas dos principais p?los cer?micos de Rio Grande do Norte. Algumas das mat?riasprimas caracterizadas foram formuladas visando obter as melhores propriedades f?sicas e mec?nicas. Em seguida, foram selecionadas mat?riasprimas e formula??es para o estudo da influ?ncia na taxa de aquecimento nas propriedades finais dos materiais cer?micos. As amostras foram conformadas por prensagem e extrus?o e submetidas ?s taxas de 1 ?C/min, 10 ?C/min e 20 ?C/min, com temperaturas finais de 850 ?C, 950 ?C e 1050 ?C. Tamb?m foram investigados os ciclos descont?nuos com taxas de 10 ?C/min ou 15 ?C/min at? 600 ?C e taxa de 20 ?C/min at? a temperatura final. Foram determinadas propriedades tecnol?gicas para todas as amostras e realizada a an?lise microestrutural em algumas condi??es de queima. Resultados indicam que ? poss?vel utilizar ciclos de queima mais r?pidos e eficientes que os atuais, limitando apenas algumas massas argilosas para certas condi??es de queima. Os melhores resultados foram obtidos para as amostras submetidas aos ciclos lentos at? 600 ?C e sinteriza??o com queima r?pida at? 950 ?C. Este trabalho apresenta como contribui??o original a utiliza??o de uma taxa de queima r?pida para mat?riasprimas e formula??es argilosas, procurando determinar as condi??es ideais de massas e de processamento para o uso de um menor tempo de queima, possibilitando assim, a utiliza??o de fornos a rolos e do g?s natural pelas ind?strias de cer?mica estrutural

Made available in DSpace on 2014-12-17T14:57:38Z (GMT). No. of bitstreams: 1 ElianaMC.pdf: 1221443 bytes, checksum: c2ecaef1ae772fb4d8e14dd13d82d037 (MD5) Previous issue date: 2007-06-02 / The potential market of the metropolitan area of Salvador accounts for the estimated consumption of roughly 800 million horizontally perforated extruded clay bricks a year. The growing demand of consumers along with the competitiveness of the structural ceramic sector has driven forward a number of recent efforts and investments towards improving the quality of structural ceramics. In this scenario, the present study focused on sampling and evaluating the conformity of 8-hole horizontally perforated extruded clay bricks manufactured by different plants (A, B and C) in the metropolitan area of Salvador. In addition, representative clay and sandy-clay materials were collected from each plant and characterized by conventional physical, chemical and mineralogical techniques. Finally, experimental compositions designated as A, B and C, according to the source, were prepared by mixing different contents of the raw materials collected in the plants, fired at different temperatures and characterized. The results revealed a series of non conformities regarding ABNT guidelines. The characterization of raw materials revealed the presence of kaolinite and ilite in concentrations ranging from 64 to 90 wt.% along with free quartz (10 - 25%). The sandy-clay samples consisted basically of kaolinite. All raw materials depicted low contents of organics, amorphous constituents, alkaline oxides and feldspar. An analysis of the firing behavior of all different ceramic compositions revealed that the linear contraction of composition A was rather significant considering the temperature range evaluated, and it justifies the significant dimensional non conformity that was shown by bricks made with the ceramic A / O mercado potencial de cer?mica estrutural na regi?o metropolitana de Salvador ? respons?vel pelo consumo de mais de 800 milh?es de pe?as/ano. Com um com?rcio cada vez mais exigente e competitivo torna-se necess?rio que as ind?strias ceramistas invistam em a??es que visem aperfei?oar a qualidade de seus produtos. O objetivo desse estudo foi avaliar o ?ndice de conformidade de blocos cer?micos e caracterizar a mat?ria-prima. Foram empregadas as normas ABNT para an?lise de conformidade de blocos cer?micos em tr?s ind?strias (A, B e C) da Regi?o Metropolitana do Salvador, bem como t?cnicas para caracteriza??o qu?mica, f?sica e mec?nica das mat?rias-primas e formula??o e an?lise das massas. Com base nos resultados alcan?ados pode-se concluir que os blocos cer?micos fabricados pelas ind?strias pesquisadas n?o apresentam conformidade com as normas t?cnicas brasileiras. Os argilominerais encontrados nas mat?rias-primas estudadas (massas A, B e C) foram a caulinita e a ilita que ficaram entre 64 a 90% e o teor de quartzo livre entre 10 e 25%. Os arenosos s?o predominantemente argilas caulin?ticas. Os materiais caracterizados apresentaram baixa concentra??o de materiais amorfos, baixo teor de ?xidos alcalinos e, conseq?entemente, concentra??es muito baixas de feldspatos. A an?lise das curvas de gresifica??o das massas demonstra que a inclina??o da curva de retra??o linear ? mais acentuada para a massa A, na faixa de temperatura estudada, e justifica a significativa n?o conformidade dimensional verificada nos blocos produzidos pela cer?mica A

Made available in DSpace on 2014-12-17T14:57:55Z (GMT). No. of bitstreams: 1 RaimundoJSP.pdf: 1219471 bytes, checksum: d712293aa14f71b340c5cbfd7467bfe4 (MD5) Previous issue date: 2010-01-12 / This study aimed to investigate the use of cane sugar ashes from small-scale stills of Eun?polis region, state of Bahia, in pottery mass that can be developed as porcelain stoneware. Bahia is the second largest producer of rum distillery in Brazil. In the production of rum is produced residue called bagasse, which is used to generate electricity in Power plants and in the distillery itself, generating ashes as residue, which is played in nature, causing environmental damage. We studied 5 (five) formulations of 0% 10% 20%, 30% and 40% by weight of the ash, without ignition and 3 (three) formulations of 10%, 20% and 30% with gray ash temperature of 1250?C. The formulation at 0% by weight of ash was used for a comparison between the traditional mass of porcelain stoneware and the masses with the addition of ash calcined, replacing feldspar. The percentage by weight of kaolin and of Clay was kept the same, 30%, and all raw materials were derived from the state of Bahia. The samples were made in uniaxial array with dimensions of (60 x 20 x 5) mm and compressed to a pressure of 45 MPa. Assays were performed to characterize the raw by X-ray fluorescence, X-ray diffraction, ATD and ATG and Dilatometric analysis. The samples were sintered at temperatures of 1100?C, 1150?C, 1200?C and 1250?C, for the specimens with the ashes without ash and 1150? C and 1200? C for specimens with the gray level of calcined 60 minutes. and then we made a cooling ramp with the same rate of warming until reach ambient temperature. The sintered bodies were characterized by water absorption, porosity, linear shrinkage, bending strength and XRD of the fracture surface and the results analyzed. It was proven, after results of tests performed, that it is possible to use the ash residue of sugar cane bagasse on ceramic coating with the addition of up to 10% wt of the residue ash / O presente trabalho visa a investigar a utiliza??o da cinza do bala?o da cana de a??car proveniente do alambique artesanal da regi?o de Eunapolis-BA em massa cer?mica que poder? ser aproveitada como um gr?s porcelanato. A Bahia e o segundo estado brasileiro maior produtor de cacha?a de alambique do Brasil. Na produ??o da cacha?a, e produzido res?duo chamado bala?o , sendo este utilizado na gera??o de energia el?trica em usinas termoel?tricas e na pr?pria destilaria, gerando uma cinza como res?duo, que e jogada na natureza, provocando danos ambientais. Foram estudadas 5 (cinco) formula??es de 0% 10%, 20%, 30% e 40% em peso de res?duo de cinza sem calcina??o e 3 (tr?s) formula??es de 10%, 20% e 30% com a cinza calcinada na temperatura de 1250oC. A formula??o em 0% em peso de cinza serviu para uma compara??o entre a massa tradicional do gr?s porcelanato em rela??o as massas com a adi??o de cinza sem calcinar e calcinada, em substitui??o ao feldspato. A percentagem em peso da argila e do caulim foi mantida a mesma, 30%, e todas as mat?rias-primas foram oriundas do estado da Bahia. Os corpos de prova foram confeccionados em matriz uniaxial com as dimens?es de (60 x 20 x 5) mm e compactados a uma press?o de 45 MPa. Foram realizados ensaios para caracteriza??o das mat?rias-primas por fluoresc?ncia de raios X, difra??o de raios X, ATD, ATG, e analise dilatometrica. As amostras foram sinterizadas nas temperaturas de 1100?C, 1150?C, 1200?C e 1250oC para os corpos de prova com a cinza sem calcinar e 1150?C e 1200?C para os corpos de prova com a cinza calcinada com patamar de 60 minutos. Os corpos sinterizados foram caracterizados por absor??o de ?gua, porosidade aparente, retra??o linear, resist?ncia a flex?o e DRX da superf?cie de fratura e os resultados analisados. Ficou comprovado, apos resultado dos ensaios realizados, que e poss?vel a utiliza??o do res?duo da cinza do bala?o da cana de a??car em massas cer?micas de revestimento, com adi??o de ate 10% wt do res?duo da cinza

Made available in DSpace on 2014-12-17T14:57:55Z (GMT). No. of bitstreams: 1 EduardoGR_TESE.pdf: 4595986 bytes, checksum: 7a13884531d20feb0680378f1e5403df (MD5) Previous issue date: 2011-10-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Ceramics with porous cellular structure, called ceramic foams, have a potential use in several applications, such as: thermal insulation, catalyst supports, filters, and others. Among these techniques to obtain porous ceramics the replication method is an important process. This method consists of impregnation of a sponge (usually polymer) with ceramic slurry, followed by a heat treatment, which will happen the decomposition of organic material and sintering the ceramic material, resulting in a ceramic structure which is a replica of impregnated sponge. Knowledge of the mechanical properties of these ceramics is important for these materials can be used commercially. Gibson and Ashby developed a mathematical model to describe the mechanical behavior of cellular solids. This model wasn?t for describing the ceramics behavior produced by the replica method, because it doesn?t consider the defects from this type of processing. In this study were researched mechanical behavior of porous alumina ceramics obtained by the replica method and proposed modifications to the model of Gibson and Ashby to accommodate this material. The polymer sponge used in processing was characterized by thermogravimetric analysis and scanning electron microscopy. The materials obtained after sintering were characterized by mechanical strength tests on 4-point bending and compression, density and porosity and by scanning electron microscopy. From these results it was evaluated the mechanical strength behavior compared to Gibson and Ashby model for solid cellular structure and was proposed a correction of this model through a factor related to struts integrity degree, which consider fissures present in the structure of these materials besides defects geometry within the struts / Cer?micas com estrutura celular porosa, denominadas espumas cer?micas, possuem o potencial de utiliza??o em uma vasta gama de aplica??es, tais como: isolamento t?rmico, suporte catal?tico, filtros, dentre outras. Dentre as t?cnicas para obten??o destas cer?micas porosas podemos destacar o m?todo da r?plica. Este m?todo consiste na impregna??o de uma esponja (geralmente polim?rica) com uma barbotina cer?mica, seguindo-se um tratamento t?rmico, onde ocorrer? a decomposi??o do material org?nico e sinteriza??o do material cer?mico, resultando em uma cer?mica cuja estrutura ? uma r?plica da esponja impregnada. O conhecimento das propriedades mec?nicas destas cer?micas ? importante para que estas possam ser utilizadas comercialmente. Gibson e Ashby desenvolveram um modelo matem?tico para descrever o comportamento mec?nico de s?lidos celulares, por?m este modelo n?o se mostrou satisfat?rio para descrever o comportamento das cer?micas obtidas pelo m?todo da r?plica, pois o mesmo n?o leva em considera??o os defeitos provenientes deste tipo de processamento. Neste trabalho estudou-se o comportamento mec?nico de cer?micas porosas de alumina obtidas pelo m?todo da r?plica, e a partir desta an?lise se prop?s modifica??es no modelo de Gibson e Ashby para se adequar a este material. A esponja polim?rica utilizada no processamento foi caracterizada atrav?s de an?lise termogravim?trica e microscopia eletr?nica de varredura. Os materiais obtidos ap?s sinteriza??o foram caracterizados atrav?s de testes de resist?ncia mec?nica, tens?o de ruptura ? flex?o (4 pontos) e compress?o, densidade, porosidade e por fim, an?lise microsc?pica por microscopia eletr?nica de varredura. A partir destes resultados avaliou-se o comportamento da resist?ncia mec?nica em compara??o ao modelo de Gibson e Ashby para s?lidos com estrutura celular e foi proposta uma corre??o deste modelo atrav?s de um fator relacionado com o grau de integridade dos filamentos, que considera as trincas presentes na estrutura destes materiais, al?m da geometria dos defeitos no interior dos filamentos