Estudo do processo de clarifica??o do ?leo de milho nos modos batelada e cont?nuo

• Ano de defesa: 2013
• Autor(a) principal: Alves, Lais de Souza
• Orientador(a): Meleiro, Luiz Augusto da Cruz
• Banca de defesa: Rojas, Edwin Elard Garcia, Pagani, M?nica Marques
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal Rural do Rio de Janeiro
• Programa de Pós-Graduação: Programa de P?s-Gradua??o em Engenharia Qu?mica
• Departamento: Instituto de Tecnologia
• País: Brasil
• Palavras-chave em Português: Adsorventes; branqueamento; ?leo vegetal
• Palavras-chave em Inglês: Adsorbents; bleaching; vegetable oil
• Área do conhecimento CNPq: Engenharia Qu?mica
• Link de acesso: https://tede.ufrrj.br/jspui/handle/jspui/3246

The refining of vegetable oils is achieved through several processing steps, however, studied in this work exclusively step of the clarifying corn oil, which is conducted through the adsorption of compounds that give color to the oil. At this stage of the process, the industry makes use of large amounts of activated clays imported that, are difficult to regenerate, increase the processing costs, and generate large amounts of industrial waste. Therefore, this study was conducted a study on the technical feasibility of this process modification, both in the adsorbent used in the clarification of the corn oil, as in the mode of operation of the process. As for adsorbent, the proposal was to evaluate the efficiency of corn cobs, a material described in the literature with considerable adsorptive power and which is part of production chain of corn oil, besides having the advantage of reutilization of waste agroindustrial. As for the mode of operation, the clarification was conducted in batch and continuous tests, using in both corn cob and earth clarifying as adsorbents. The corn cob went through stages of treatment and their power to clarify was tested in batch tests, where they were evaluated the variables temperature, time and particle size of cob. In trials in continuous mode, the operation was conducted in a fixed bed column of 0.5 m in height and 0.0508 m diameter, coupled to a pump and pressure gauges at the entrance and exit of the column to the accompaniment of the head loss caused by the type and conditions of the filling. Clay clarification efficiency was also determined by two modes of operation, where it was verified the effect of temperature. In the continuous mode was also evaluated the simultaneous use of both adsorbents in different proportions for the packaging of bed, varying the amount of adsorbents and the particle size of the cob at room temperature. Process performance was evaluated on absorbance measures and through colorimetric parameters. Finally, a thermodynamic analysis was performed of the processes studied by comparing the values of the parameters ?G, ?H e ?S. Through the results obtained, it can be affirmed that the clarification power of clay was significantly higher than that of corn cob. Tests on a continuous mode in a fixed bed column were performed successfully, despite some operational constraints inherent in the equipment used. Nevertheless, the results suggest that the clarification of the corn oil in continuous mode presents important advantages compared to batch operation used industrially. Thermodynamic analysis of batch and continuous processes, using clay or corn cob as adsorbent, revealed through the parameters ?G, ?H that the processes of clarification of corn oil are spontaneous and endothermic. Furthermore, the positive values of ?S showed certain degree of organization of the molecules in the solid-liquid interface of the processes investigated