Navegando por Autor "MELO, Alvino Oliveira"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Estudo da sinterização em reator vertical de leito fixo para produção de agregado sintético
(Universidade Federal do Pará, 2017-06) QUARESMA, Danielly da Silva; NEVES, Alacid do Socorro Siqueira; MELO, Alvino Oliveira; PEREIRA, Luiz Felipe Silva; BEZERRA, Pamela Tais Silva; MACÊDO, Emanuel Negrão; SOUZA, José Antônio da Silva
The synthetic aggregates are being employed in civil construction for the reduction of mineral extraction activities. Within this context, the recycling of industrial waste is the basis of the majority of processes to reduce the exploitation of mineral resources. In this work the sintering in a vertical fixed bed reactor for synthetic aggregate production using 20% pellets and 80% charcoal was studied. The pellets were prepared from a mixture containing clay, charcoal and fly ash. Two experiments varying the speed of air sucking were carried out. The material produced was analyzed by X-ray diffraction, scanning electron microscopy, measures of their ceramic properties, and particle size analysis. The results showed that the solid-state reactions, during the sintering process, were efficient and the produced material was classified as coarse lightweight aggregate. The process is interesting for the sintering of aggregates, and can be controlled by composition, particle size, temperature gradient and gaseous flow.
Acesso aberto (Open Access)
Sinterização de pelotas de argila, carvão vegetal e cinza volante de caldeira em uma célula de combustão de leito fixo: análise da propagação da frente de reação de combustão no leito
(Universidade Federal do Pará, 2016-05-20) MELO, Alvino Oliveira; MACÊDO, Emanuel Negrão; http://lattes.cnpq.br/8718370108324505; MARTINS, Marcio Ferreira
A great preoccupation of humanity turns around the preservation of the environment, seeking to constantly through studies and search, alternatives to find a balance of coexistence between man and nature. Normally, industries in general, produce waste at its majority toxic which damage the environment, humans being and other diversities of life inserted in it. Looking up, insert itself in this context, this work makes a study of evolution of the temperature of combustion of a mixture, in predefined proportions of fly ash from boiler industries located in the State of Pará, clay from the banks of the Guamá River and charcoal acquired in metropolitan region of Belem-Pa, Brazil. The experiments were performed in a combustion reactor, acquired by Programa de Pós - Graduação em Engenharia de Recursos Naturais da Amazônia in order to assess the temperature profile of each experiment during the combustion process and if the values of these temperatures would be sufficient to initiate the process of sintering of the pellets. For the experiments performance, parameters such as inlet velocity of the fluid (air), diameters of the pellets (mixture of charcoal, ash and clay) and grain size of charcoal were varied and the effect of variations of these parameters were analyzed for each experiment. The historical temperatures were recorded by a data acquisition instrument named Paperless Recorder - PHL and subsequently plotted for analysis. Temperatures varying in the range of 800°C - 1290°C, were obtained and these values are sufficient to initiate the process of sintering of the pellets. Data generated by the combustion reactor were recorded by "Paperless Recorder" and compared with numerical results computational.