Incorpora??o de cinzas da casca de caf? na produ??o de placas cer?micas para revestimento

• Main Author: Dultra, Eduardo Jorge Vidal
• Other Authors: CPF:50580396720
• Format: Others
• Language: Portuguese
• Published: Universidade Federal do Rio Grande do Norte 2014
• Subjects: Porcelanato; Res?duos; Cinzas da casca de caf?; Fundentes; Propriedades; Porcelain stoneware tiles; Residue; Coffee husk ash; Fluxing agents; Properties; CNPQ::ENGENHARIAS::ENGENHARIA MECANICA
• Online Access: http://repositorio.ufrn.br:8080/jspui/handle/123456789/15610

Made available in DSpace on 2014-12-17T14:57:59Z (GMT). No. of bitstreams: 1 EduardoJVD_DISSERT.pdf: 2741868 bytes, checksum: 97ddceb816029ff94f808bc361679f56 (MD5) Previous issue date: 2010-01-12 === Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior === Brazil is the world s leading coffee producer. In 2008, 45.99 million of 60 kg bags of benefited coffee were produced. In the process of improvement 50% is grain and 50% is husk, thus, 1.38 million tons of coffee husk are produced annually. The husk is used as combustible in the drying and improvement ovens in the coffee farms, generating ash as residue. These ashes contain a high concentration of alkaline metals and earth metals, mainly K2O and CaO. This work studies the use of this residue in the ceramic tiles industry, as fluxing agents in substitution to the feldspar. Ten mixtures with equal ratios of clay and kaolin, proceeding from Bahia and the residue (varying from 30 to 5%) were defined and produced in uniaxial tool die of 60x20mm with approximately 5 mm of thickness and 45MPa compacting pressure. The samples were fired in four different temperatures: 1100 ?C, 1150 ?C, 1185 ?C and 1200 ?C during 60 minutes and characterized by means of X-ray fluorescence, X-ray diffraction, gravimetric thermal analysis and differential thermal analysis. The results of water absorption, apparent porosity, linear shrinkage, XRD, dilatometry, flexural strength and SEM were also analysed. The test specimen with addition of 10% of ash fired in 1200 ?C resulted in 0.18% water absorption and 40.77 MPa flexural strength, being classified as porcelain stoneware tiles according to ABNT, UNI and ISO norms === O Brasil ? o maior produtor mundial de caf?. Em 2008 foram produzidas 45,99 milh?es de sacas, de 60 Kg, de caf? beneficiado. No processo de beneficiamento 50% ? gr?o e 50% ? casca. Assim, 1,38 milh?es de toneladas de cascas de caf? s?o produzidas anualmente. A casca ? utilizada como combust?vel nos fornos de secagem e beneficiamento nas fazendas de caf?, gerando uma cinza como res?duo. As cinzas da casca de caf? apresentam altas concentra??es de metais alcalinos e alcalinos-terrosos, principalmente K2O e CaO. Este trabalho estuda a utiliza??o deste res?duo na ind?stria de placas cer?micas para revestimentos, como fundente, em substitui??o ao feldspato. Foram definidas 10 formula??es com iguais propor??es de argila e caulim provenientes da Bahia, e o res?duo (variando de 30 a 5%), e confeccionados corpos-de-prova em matriz uniaxial de 60x20mm com aproximadamente 5 mm de espessura, com press?o de compacta??o de 45Mpa. As amostras foram sinterizadas em quatros patamares de temperatura, 1100 ?C, 1150 ?C, 1185 ?C e 1200 ?C durante 60 minutos. Foram realizados ensaios para caracteriza??o das mat?rias-primas por fluoresc?ncia de raios-X, difra??o de raios-X, AG, ATD e ATG e analisados os resultados de absor??o de ?gua, porosidade aparente, retra??o linear, DRX, an?lise dilatom?trica, resist?ncia ? flex?o e MEV. Os corpos de prova com adi??o de 10% da cinza e sinterizados a 1200 ?C obtiveram resultados de absor??o de ?gua de 0,18% e resist?ncia ? flex?o de 40,77 MPa, o que segundo as normas ABNT, UNI e ISO podem ser classificados como gr?s porcelanato