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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Resultados da Pesquisa
Item Analysis of the coffee peel application over the soil-cement bricks properties(Editora UFLA, 2019-01) Castro, Eliziane Denize de; Villela, Luciana Silva; Mendes, Lourival Marin; Mendes, Rafael Farinassi; Ribeiro, André Geraldo Cornélio; Guimarães Junior, José Benedito; Rabelo, Giovanni FranciscoThe development of materials that use less polluting manufacturing techniques and can be manufactured from agricultural and/or industrial waste is an increasingly explored field of research. The objective of this work was to study the effects of the coffee peel particles (Coffea arabica L.) incorporation in partial replacement of cement, on the physical, mechanical and thermal properties of bricks, at different ages. For this purpose, soil corrected with sand, Portland cement type CP II F-32 and coffee peel particles were used. After the initial percentage of cement in the mixture was defined as 10%, coffee peels were added in relation to cement, equal to 5%, 10%, 15% and 20%. The bricks were submitted to simple compression tests, at the ages of 14, 28 and 56 days, thermal insulation at 28 days. The increase in peel content caused increases in water absorption, and reduction of compressive strength and apparent specific dry mass. The interaction between the shell content and the age of the specimens was significant only for the variable resistance to compression. The thermal conductivity found for the material showed its insulating potential, with values below those determined for ceramic bricks. In general, it can be concluded that the material produced did not fit in the normative requirements for soil-cement bricks, however, the mechanical characteristics found in there, indicate the possibility of use in rustic constructions, such as those ones made with adobe bricks.Item Efeito da incorporação de casca de café nas propriedades físico-mecânicas de painéis aglomerados de Eucalyptus Erophylla S.T. Blake(Editora UFLA, 2010-05) Mendes, Rafael Farinassi; Mendes, Lourival Marin; Guimarães Júnior, José Benedito; Mori, Fábio Akira; César, Antonia Amanda da SilvaNeste trabalho objetivou-se avaliar a influência da incorporação de casca de café nas propriedades físico-mecânicas de painéis aglomerados produzidos com Eucalyptus urophylla S.T. Blake. Os painéis foram produzidos com incorporação de 25, 50 e 75% de casca de café, em três teores da resina fenol-formaldeído (6, 9 e 12%) e 1% de parafina. A densidade nominal dos painéis foi de 0,7 g/cm3 e o ciclo de prensagem compreendeu uma pressão de 3,92 MPa e temperatura de 180oC por 8 minutos. Pelos resultados obtidos foi possível observar que: as propriedades físicas dos painéis aglomerados apresentam relação linear decrescente com o aumento do teor de resina, e crescente com a porcentagem de casca de café, apresentando maiores valores de absorção de água e inchamento em espessura. As propriedades mecânicas apresentam relação linear crescente com o aumento do teor de resina, e decrescente com a porcentagem de associação de casca de café. Do modo que a pesquisa foi conduzida, a incorporação da casca de café prejudica a qualidade dos painéis produzidos.Item Thermal decomposition of torrefied and carbonized briquettes of residues from coffee grain processing(Editora UFLA, 2013-05) Protásio, Thiago de Paula; Melo, Isabel Cristina Nogueira Alves de; Guimarães Junior, Mario; Mendes, Rafael Farinassi; Trugilho, Paulo FernandoThe use of biomass has been recognized as a potential renewable energy and an alternative substitute that contributes to the decrease of fossil fuels consumption. Therefore, this research aimed to analyze the thermal behavior of briquettes made of residues from coffee grain processing in different conditions: in natura, torrefied and carbonized. Eucalyptus sawdust was used for comparison. The briquettes were carbonized considering final temperature of 450o C (kept for 30 min). The briquettes torrefaction was performed in an electric oven (muffle) using two heating rates until 250o C (kept 60 min). The thermal-gravimetric analysis was made in nitrogen atmosphere until the temperature of 600o C. The contents of fixed carbon and volatile matter of the fuels were determined. The carbonized briquette of residues from coffee grain processing presented higher stability and low thermal decomposition. It was observed a low influence of torrefaction heating rate under thermal properties of briquettes, and fixed carbon and volatile matter content. Regarding the raw biomass, lower total mass loss was observed for the residues from coffee grain processing when compared to Eucalyptus sawdust. The carbonized and torrefied briquettes presented higher hydrophobicity than raw briquettes.Item Eucalyptus wood and coffee parchment for particleboard production: physical and mechanical properties(Editora UFLA, 2017-03) Scatolino, Mário Vanoli; Costa, Andrey de Oliveira; Guimarães Júnior, José Benedito; Protásio, Thiago de Paula; Mendes, Rafael Farinassi; Mendes, Lourival MarinThe wood panel industry is constantly growing, being necessary the innovation in technologies and raw materials to improve the quality of the final product. Considering the shortage and pressure to decrease the dependence of wood, there is an interest in other renewable materials such as agricultural wastes. Among these wastes, coffee parchment is one which deserves notoriety. An alternative use for coffee parchment could be for production of particleboard in association with wood particles. This study aimed to evaluate the feasibility of using coffee parchment for production of particleboard. The following percentages of wastes were used: 0, 10, 20, 30, 40 and 50% in association to eucalyptus wood. The panels were produced with 8% of urea formaldehyde (based on dry weight of particles). The pressing cycle consisted by: pre-pressing of 0.5 MPa for 10 minutes followed by pressing of 4.0 MPa, and temperature of 160° C for 15 minutes. The compaction ratio of particleboards produced using higher quantities of parchment improved the physical properties. The properties of Water Absorption (2 and 24 h) and Thickness Swelling (2 h) decreased with increasing percentage of coffee parchment. The Thickness Swelling (24 h) showed not significant effect with an increase of coffee waste. The Modulus of Elasticity for coffee parchment particleboards was in the range 646.49 ± 112.65 to 402.03 ± 66.24 MPa, while the Modulus of Rupture ranged from 8.18 ± 1.39 to 4.45 ± 0.75 MPa. The results showed that 10% of coffee parchment could be added for production of particleboards.