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Considering that an analysis of both dynamic behavior and controllability of an extractive distillation process is important, and also taking into consideration the absence of studies in literature related to the influence of heat integration and solvent content on the controllability of this process, this work aims to investigate such aspects, or more specifically, investigate the dynamic responses in the presence of feed disturbances when operating at high, medium, and low solvent content. The production of anhydrous ethanol as the main product with ethylene glycol as solvent was the case study in this work, and a control scheme based on recent studies was used to perform this study. It was verified that the solvent content in the extractive section has an influence on top product composition when feed flow rate and composition disturbances are introduced in the azeotropic mixture feed stream; the system with high solvent content presented the highest offsets. The results also showed that the presence of heat integration causes considerable changes in the temperature of the recycled solvent stream when disturbances occur in the system feed flow rate, affecting the purity of the top product. A modification in the control scheme was proposed for the system with high solvent content, significantly improving the control of ethanol purity. The new control scheme includes two temperature control loops in the extractive column and a temperature control loop in the recycled solvent stream, using a bypass stream around the heat exchanger. It was also verified that the dimensions of the extractive column and reflux vessel are smaller when the system is configured to operate with a high solvent content.

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Purpose The benefits of adopting lean manufacturing for leveraging corporate sustainability have been highlighted in the literature. However, these studies have neglected the social side of sustainability compared with the attention given to the environmental aspects. Addressing this gap, this paper aims to investigate the influence of lean practices on the dimensions of employee social sustainability (ESS), which enabled the identification of the most critical practices. Design/methodology/approach This paper conducted an exploratory study in two phases: first, seeking evidence in the literature, and second, applying the analytic hierarchy process (AHP) to connect ESS to lean practices based on expert opinion. Findings From the literature review, this paper found linkages between eight lean manufacturing practices and four dimensions of ESS. Based on evidence from the literature, the authors designed and applied an AHP model to set priorities among lean practices and social dimensions. Therefore, “health and safety” was evaluated as the most critical social dimension, and 5S was considered the most influential lean practice on ESS. Originality/value This study contributed to introducing the perspective of lean manufacturing practices as enablers of ESS. Notably, it pointed out which specific practices should be prioritized in the lean implementation process with social sustainability purposes. In addition, it identified relationships not reported in the literature, raising questions for further investigation.

Iron in blood cells has several physiological functions like transporting oxygen to cells and maintaining iron homeostasis. Iron is primarily contained in red blood cells (RBCs), but monocytes also store iron as these cells are responsible for the recycling of senescent RBCs. Iron also serves an important role related to the function of different leukocytes. In inflammation, iron homeostasis is dependent on cytokines derived from T cells and macrophages. Fluctuations of iron content in the body lead to different diseases. Iron deficiency, which is also known as anemia, hampers different physiological processes in the human body. On the other hand, genetic or acquired hemochromatosis ultimately results in iron overload and leads to the failure of different vital organs. Different diagnoses and treatments are developed for these kinds of disorders, but the majority are costly and suffer from side effects. To address this issue, magnetophoresis could be an attractive technology for the diagnosis (and in some cases treatment) of these pathologies due to the paramagnetic character of the cells containing iron. In this review, we discuss the main functions of iron in blood cells and iron‐related diseases in humans and highlight the potential of magnetophoresis for diagnosing and treating some of these disorders.