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The present work aims to evaluate the effect of granulometry (particle size and particle size distribution) on the manly physical properties of bidisperse bulk solids, such as bulk density, porosity, cohesion, compressibility and basic flow energy. Therefore, two groups of mixtures comprising commercial sands with different sizes were prepared. The first group (G1) consisted on adding two sort of fine quartz powder (particle undersize of 200 and 600 mesh) into commercial sand 50/60 (coarse). The second group (G2) was formulated adding commercial sand (80/100 and 50/60) added into coarse one (40/50). All mixtures were tested at static and dynamic conditions and at incipient transition (shear test). As result, it was observed higher interactions for smaller quartz’s particles that lead to form agglomerates, increasing bulk porosity and reducing bulk density of non-consolidated mixtures comprising this sort of material. Fine particles at group 1 mixtures have also improved the quality of fluidization, but decrease powder flowability increasing cohesion. The results obtained for group 2 mixtures have revealed no significant changes on bulk properties as increasing fine particle into coarse one. This is could be attributed to the low ratio between fine and coarse particles, changing particle packing, once the interspaces between coarse particles could not be filled with fine one. Este trabalho teve como o objetivo avaliar o efeito da granulometria (tamanho das partículas e faixa de distribuição granulométrica) nas principais propriedades físicas de leitos bi dispersos, tais como densidade aparente, porosidade, coesão, compressibilidade e energia básica de fluxo. Para tanto foram confeccionados dois grupos de misturas envolvendo areias comerciais com diferentes granulometrias. O primeiro grupo (G1) consistiu na incorporação de dois tipos de areias de quartzo (partículas menores que mesh 200 e mesh 600) em um de tipo de areia de sílica comercial 50/60 (grosso). O segundo grupo (G2) constituiu em misturas de areias de sílica 40/50 (grosso) mediante adição de partículas de menor granulometria de areia de sílica 50/60 e 80/100. Todas as misturas foram analisadas em condições estáticas, dinâmicas e na iminência do movimento (cisalhamento). Como resultado observou-se uma maior tendência por parte das partículas de tamanho reduzido em formar aglomerados, aumentando a porosidade e diminuindo densidade aparente quando não consolidadas. A presença de partículas de tamanho reduzido nas misturas do grupo 1 também melhorou a fluidização das misturas deste grupo, mas prejudicou a fluidez aumentando a coesão do meio. Os resultados obtidos para o grupo 2 de misturas não apresentaram diferenças significativas em suas características com a incorporações de finos. Isto se deve a baixa relação entre o tamanho das partículas, de maneira que as partículas menores não cabem nos interstícios das partículas maiores.The present work aims to evaluate the effect of granulometry (particle size and particle size distribution) on the manly physical properties of bidisperse bulk solids, such as bulk density, porosity, cohesion, compressibility and basic flow energy. Therefore, two groups of mixtures comprising commercial sands with different sizes were prepared. The first group (G1) consisted on adding two sort of fine quartz powder (particle undersize of 200 and 600 mesh) into commercial sand 50/60 (coarse). The second group (G2) was formulated adding commercial sand (80/100 and 50/60) added into coarse one (40/50). All mixtures were tested at static and dynamic conditions and at incipient transition (shear test). As result, it was observed higher interactions for smaller quartz’s particles that lead to form agglomerates, increasing bulk porosity and reducing bulk density of non-consolidated mixtures comprising this sort of material. Fine particles at group 1 mixtures have also improved the quality of fluidization, but decrease powder flowability increasing cohesion. The results obtained for group 2 mixtures have revealed no significant changes on bulk properties as increasing fine particle into coarse one. This is could be attributed to the low ratio between fine and coarse particles, changing particle packing, once the interspaces between coarse particles could not be filled with fine one.

The extraction of soybean oil is made almost exclusively by the solvent extraction method, which uses the commercial hexane. In order to evaluate new solvents as an alternative to the traditional extraction process, an study of soybean oil extraction process using mixtures of ethanol, ethyl acetate and isopropanol as solvent were carried out. As results, the best extraction yield was obtained by the mixture containing 85% of ethanol, 13% of isopropanol and 2% of ethyl acetate (0,185g oil/g of soybean). Despite of the obtained oil presents the acidity and saponification index divergent from ANVISA’s specification for crude soybean oil, the refinement of this oil has improved some of its properties, such as the acid index: 0,7% of oleic acid (specified

L’objet de ce travail repose initialement sur la problématique de la manipulation des milieux granulaires et de leur stockage. La caractérisation des propriétés physiques et l’aptitude à l’écoulement d’une poudre industrielle a été réalisée. Cependant, ces techniques ont leurs limitations et le problème abordé a requis le développement d’un nouveau protocole concernant le vieillissement des poudres. Ce protocole permet non seulement l’obtention de résultats plus représentatifs pour des phénomènes à l’échelle industrielle, mais également une extrapolation du vieillissement pour de longues périodes de temps. D’autre part, un modèle analytique permettant d’estimer la cohésion à partir de la forme du tas de poudres à faibles contraintes a été conçu. Enfin, une étude sur la rupture et la cohésion macroscopique des milieux granulaires humides en fonction de la quantité de liquide a été également réalisée.

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Various processes in food, pharmaceutical and chemical industries have to handle with solid particles at some point during their processes. From the manufacturing process to storage of these materials, interparticle forces may intensify and lead to serious issues as incrustation inside the equipment or blocking a silo output. Therefore, it becomes necessary a better understanding about particle systems flowability, which include a good physical chemistry characterization and morphology associated with flow parameters analysis that will help on the flowability prediction. The purpose of this work was to investigate the flowability of four types of sugars: icing sugar from União® (IS), granulated sugar from Colombo® (GS), very high polarization (VHP) sugar from São Martinho industry (VS) and refined sugar from União® (RS), through classical tests as repose angle and Hausner ratio and dynamic tests in rheometer. For particle characterization, sieving was conducted to obtain size distribution and scanning electron microscopy (SEM) for morphology visualization. GS and VS types presented to be more similar in shape and size, with crystal configuration and higher particle mean diameter. RS and IS, on the other hand, showed greater percentage of fines and irregular shape, where IS was the type with more agglomerates. Cohesive forces were more noticeable in the IS type since this is the sugar with the smallest grain size distribution. As a consequence, this presented a greater resistance to flow, with a Hausner ratio of 1,33 (good flowability is between 1.12-1.18) and the higher angle of repose of 40º. Dynamic shear tests were made in powder rheometer FT4 from Freeman Technology and returned uncertain data for GS and VS, evidencing that this equipment may not be suitable for this kind of material. Compressibility analysis always showed greater values in dynamic condition than static ones and despite of GS and VS similarities, GS and RS were closer in compaction kinetics due the related values of D90. Overall, one may say sugar IS had the worst flowability among the 4 types following by RS wich is the second with a greater number of fines. VS and GS were classified as free flow materials according to classical tests. However, powder rheometer presented some limitations to higher particle size (about 1 mm) materials analysis. On the other hand, as seen in classical tests, IS and RS showed similarity in some tests made using powder rheometer. Diversos processos nas indústrias de alimentos, farmacêutica e química utilizam materiais particulados em alguma etapa do processo. Durante o processamento ou armazenagem, forças interparticulares podem se intensificar e gerar graves problemas como obstrução em equipamentos ou bloqueio na saída de silos. É necessário um melhor entendimento sobre a fluidez dos sólidos particulados, através de caracterização físico-química e morfológica, associadas à análise de parâmetros de fluxo desses materiais. O objetivo deste trabalho foi avaliar a propriedades de escoamento de quatro tipos de açúcar: o açúcar de confeiteiro “glaçúcar” da União® (IS), cristal da marca Colombo® (GS), tipo exportação ou ‘very high polarization’ - VHP, da usina São Martinho® (VS) e o refinado da União® (RS). A fluidez foi avaliada por testes clássicos (ângulos de repouso e índices de Hausner) e dinâmicos, em reômetro de sólidos. Para a caracterização, realizaram-se análises de peneiramento e microscopia eletrônica para morfologia. Os tipos GS e VS foram similares morfologicamente, com arestas bem definidas e elevada granulometria dos cristais. Já RS e IS apresentaram maior quantidade de finos e formato irregular, com aglomerados mais evidentes em IS. Forças coesivas foram mais pronunciadas no açúcar IS, devido sua baixa granulometria. Este apresentou maior resistência ao escoamento, com índice de Hausner de 1,33 (boa fluidez está entre 1.12-1.18) e ângulo de repouso estático de 40°, maior entre os açúcares testados. Testes dinâmicos de cisalhamento no reômetro de pós FT-4 da Freeman™ mostraram que este equipamento foi adequado para caracterizar a fluidez dos açúcares RS e IS, mas os resultados para os açucares de maior granulometria (GS e VS) não foram consistentes. Já a compressibilidade mostrou-se sempre maior quando aplicadas condições dinâmicas e apesar de maiores semelhanças físicas de GS com VS, as curvas de compressibilidade de GS e RS foram mais similares. No geral, afirma-se que o açúcar IS é o material de pior fluidez e que RS, devido à presença de finos é classificado como o segundo pior entre os materiais. VS e GS são classificados como materiais de fácil escoamento pelos testes clássicos, e independe da tensão de consolidação aplicada. Testes em reômetro de sólidos mostraram que essa técnica é limitada para materiais de granulometria próximas a 1 mm, mas alguns resultados para amostras de menor granulometria (RS e IS) apresentaram similaridade, assim como nos testes clássicos. CNPq: 132159/2015-5