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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

Estudo do potencial de utiliza??o do res?duo da extra??o de esmeraldas na fabrica??o de cer?mica de revestimento / Study of the potential use of waste from the extraction of emerald in the manufacture of ceramic tile

Cavalcante, Ronaldo Fonseca 09 March 2010 (has links)
Made available in DSpace on 2014-12-17T14:57:56Z (GMT). No. of bitstreams: 1 RonaldoFC_DISSERT.pdf: 4616662 bytes, checksum: 0873d4d0b759a28864c474fb890be216 (MD5) Previous issue date: 2010-03-09 / Universidade Federal do Rio Grande do Norte / Companies involved in emerald mining and treatment represent an important area of industrial development in Brazil, with significative contribution to the worldwide production of such mineral. As a result, large volumes of emerald waste are constantly generated and abandoned in the environment, negatively contributing to its preservation. By the other side the interest of the use of mining waste as additive in ceramic products has been growing from researchers in recent years. The ceramic industry is constantly seeking to the marked amplification for the sector and perfecting the quality of the products and to increase the variety of applications. The technology of obtaining of ceramic tiles that uses mining residues assists market niches little explored. In this scenario, the objective of the present study was to characterize the residue generated from emerald mining as well as to assess its potential use as raw material for the production of ceramic tiles. Ceramic mixtures were prepared from raw materials characterized by X-ray fluorescence, X-ray diffraction, particle size analysis and thermal analysis. Five compositions were prepared using emerald residue contents of 0%, 10%, 20%, 30% and 40%. Samples were uniaxially pressed, fired at 1000, 1100 and 1200?C and characterized aiming at establishing their mineralogical composition, water absorption, apparent porosity, specific mass, linear retraction and modulus of rupture. The results shows that the emerald residue, basically consisted of 73% of (SiO2 + Al2O3) and 17,77% of (MgO + Na2O+ K2O) (that facilitates sintering), can be added to the ceramic tile materials with no detrimental effect on the properties of the sintered products / Empresas envolvidas na minera??o de esmeralda e beneficiamento representam uma importante ?rea de desenvolvimento industrial no Brasil, com significativa contribui??o para a produ??o mundial desse min?rio. Como resultado, grandes volumes de res?duos de esmeralda s?o constantemente gerados e abandonados no ambiente, contribuindo negativamente para a sua preserva??o. Por outro lado o interesse no uso do res?duo de minera??o como aditivo na produ??o de material cer?mico tem crescido entre os pesquisadores nos ?ltimos anos. A ind?stria cer?mica est? constantemente buscando a amplia??o do mercado para o setor e tentando aperfei?oar a qualidade dos produtos e aumentar a variedade de aplica??es. A tecnologia de obten??o de cer?mica de revestimento que usa res?duos de minera??o ? um mercado ainda pouco explorado. Neste cen?rio, o objetivo do presente estudo foi caracterizar o res?duo gerado a partir de minera??o de esmeralda, bem como para avaliar seu potencial uso como mat?ria-prima para a produ??o de revestimentos cer?micos. Misturas cer?micas foram preparadas a partir de mat?rias-primas caracterizadas por fluoresc?ncia de raios X, difra??o de raios X, an?lise granulom?trica e an?lise t?rmica. Cinco composi??es foram preparadas utilizando ?ndices de res?duos de esmeraldas de 0%, 10%, 20%, 30% e 40%. As amostras foram prensadas uniaxialmente, sinterizadas em 1000, 1100 e 1200 ? C e caracterizadas visando estabelecer sua composi??o mineral?gica, absor??o de ?gua, porosidade aparente, massa espec?fica, retra??o linear e m?dulo de ruptura. Os resultados mostraram que o res?duo de esmeraldas composto basicamente de 73% de (SiO2 + Al2O3) e 17,77% de (MgO+Na2O+K2O) (que facilitam a sinteriza??o) pode ser incorporado na massa de revestimento cer?mico sem comprometimento das propriedades do produto sinterizado

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