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The vapor phase, in parastillation, or the liquid phase, in metastillation columns, is divided at least into two internal flows. Two questions are addressed: (ii) Is splitting into two equal streams the best solution or can different split ratios have advantages? (ii) How sensitive is the process performance to fluctuations around the selected partition rate? Depending on the answers, these columns may require specific control systems. Nine split ratios, including the usual 50:50, were considered in binary and multicomponent alcoholic distillation. Separation is slightly sensitive to the split ratio, being more influenced by the Murphree efficiency. The effect of the split ratio decreases as the amount of ethanol in the feed increases. Fluctuations around the selected partition ratio do not affect, in a significant way, the process performance, and the corresponding control systems are not required. The obtained results indicate that it is better to improve tray efficiency than to control the phase split ratio.

Understanding the molecular‐level mechanisms of vegetable oil extraction and degumming remains limited. This study aimed to investigate these processes using molecular dynamics (MD), with a focus on the challenges associated with replacing n‐hexane with ethanol. MD simulations with a coarse‐grained force field (Martini 3) were conducted to examine the behavior of phospholipid mono/bilayers with and without triacylglycerol in various solvents, including water, absolute and aqueous ethanol (with 0%–10% water content by weight), and n‐hexane. Trilinolein and phospholipids with 16–18 carbon tails and 0–2 unsaturations were considered. The degree of unsaturation and tail size of phospholipids did not significantly affect bilayer formation in water. However, they influenced bilayer organization, as measured by the order parameter, bilayer thickness, and area. The phospholipid bilayer, composed of 1‐palmitoyl‐2‐oleoyl‐sn‐glycero‐3‐phosphocholine (POPC), exhibited a well‐defined structure in water, partial disruption in ethanol, and complete disruption in n‐hexane. The presence of triacylglycerol had no effect on phospholipid monolayers in water but increased lipid disorder in ethanol. Minor amounts of water in ethanol did not significantly alter the behavior of the lipid layers. MD simulations, combined with artificial intelligence, identified and quantified the formation of micelles during the degumming process, both in conjunction with n‐hexane extraction and independently as a function of water concentration. The volume and number of micelles were strongly influenced by the water content. Molecular dynamics in food engineering is relatively limited and scarce because of the complex nature of the systems. However, this study successfully demonstrates its applicability in this context.

Distillation efficiency can be improved by columns with multiple phase divisions, also known as parastillation (vapor division) and metastillation (liquid division). Although, previous studies demonstrate that these configurations improve separation efficiency, little is known about the mechanisms that cause this improvement. These mechanisms are elucidated through exergetic and driving force analyses. Methanol-ethanol and multicomponent hydrated bioethanol purifications were investigated. Thermodynamic efficiency and exergy losses are improved when the number of phase divisions is increased. In methanol-ethanol distillation, the increase of the number of phase divisions from one to eight decreases both the operational costs and CO 2 emissions by 34% and increases thermodynamic efficiency by 23%. Considering a more feasible number of phase divisions, from the construction point of view, four divisions improve operational costs by 31%, over one division. In the production of hydrated bioethanol, four-vapor divisions lead to a reduction in energy consumption by 18% when compared with conventional distillation. This study shows that it is possible to reduce operating costs to a value close to the theoretical minimum, without a significant increase in capital costs. This observation contrasts with the conventional process, in which the reduction in operating costs necessarily leads to higher distillation columns and capital costs.

Para- e metadestilação são propostas de mudanças na conformação de uma coluna de destilação, visando o aumento da eficiência energética e redução de custos. Na paradestilação, o vapor é dividido em duas correntes paralelas, de forma que o líquido, passando por todos os estágios, entre em contato com cada fração de vapor alternadamente. De forma análoga, na metadestilação a divisão ocorre na fase líquida. Nestes dois métodos, a coluna necessita de uma menor área de contato líquido-vapor, resultando em colunas de menores alturas e quedas de pressão. A análise exergética é usada neste trabalho para avaliar, comparativamente, a eficiência termodinâmica dessas colunas, e estudar o efeito da condição térmica da alimentação. O estudo foi realizado com mistura binária etanol-metanol, a partir de simulações feitas em MatLab®, pela adaptação do algoritmo proposto por Naphtali &Sandholm.