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Letteratura scientifica selezionata sul tema "Extraction intensification"

Autore: Grafiati

Pubblicato: 11 gennaio 2025

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Articoli di riviste sul tema "Extraction intensification"

1

Tang, Zhigang, Zhimin He, Hongwei Li, Dong Guo e Zhijun Zhao. "Process Intensification in Tiopronin Extraction". International Journal of Chemical Engineering and Applications 7, n. 6 (dicembre 2016): 433–36. http://dx.doi.org/10.18178/ijcea.2016.7.6.620.

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2

Babenko, Yu I., e E. V. Ivanov. "Optimizing the intensification of extraction". Theoretical Foundations of Chemical Engineering 46, n. 2 (aprile 2012): 149–52. http://dx.doi.org/10.1134/s0040579512010010.

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3

Bart, H. J., C. Drumm e M. M. Attarakih. "Process intensification with reactive extraction columns". Chemical Engineering and Processing: Process Intensification 47, n. 5 (maggio 2008): 745–54. http://dx.doi.org/10.1016/j.cep.2007.11.005.

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4

Belghith, Yosra, Imen Kallel, Maxence Rosa, Panagiotis Stathopoulos, Leandros A. Skaltsounis, Noureddine Allouche, Farid Chemat e Valérie Tomao. "Intensification of Biophenols Extraction Yield from Olive Pomace Using Innovative Green Technologies". Biomolecules 13, n. 1 (29 dicembre 2022): 65. http://dx.doi.org/10.3390/biom13010065.

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Olive pomace is the main by-product generated by the olive oil production process. Although toxic to the environment, olive pomace is an important source of natural antioxidants due to its high content of phenolic compounds. The aim of the current study is to maximize the extraction yields of the main phenolic compounds present in olive pomace using innovative green technologies. For this purpose, the present work is divided into two parts. The first part is based on a solubility study of targeted phenolic compounds in various ethanol/water ratios at two different temperatures (20 °C and 50 °C). A computational prediction using COSMO-RS software was applied for the calculation of eventual solubility, which was subsequently confirmed by practical experiments. The determination of the optimal extraction conditions of solvent ratio (EtOH/H2O) (60:40 v/v) and temperature (50 °C) led to the second part of the work, which concerns the intensification of extraction yields. Furthermore, various green extractions using innovative technologies, including accelerated solvent extraction (ASE), ultrasound with its both system (probe (UAE-P) and bath (UAE-B)), bead milling (BM) and microwave (MAE), were carried out and then compared to conventional maceration (CM). Results showed that ASE was the most effective method for extracting phenolic compounds from dried olive pomace powder (5.3 milligrams of tyrosol equivalent (TE) per gram of dried olive pomace powder (DOP)) compared to CM (3.8 mg TE/g DOP).

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Moskalenko, Tatiana, Valery Mikheev e Elena Vorsina. "Intensification of humic acid extraction from lignites". E3S Web of Conferences 192 (2020): 02024. http://dx.doi.org/10.1051/e3sconf/202019202024.

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One of the methods of initial properties of solid fuels changing by their organic mass oxidation is considered in the paper. Creation of innovative ways of intensification of existing solid fuels processing and their adoption by industry has always been and remains an actual task. Thus the chemical process is the most important stage of raw materials processing into target products. Chemical exposure allows to optimize the technological mode, expanding the scope of control of technological process parameters and, to a certain extent, modify the properties of the resulting products. The article presents the results of experimental research of influence of preliminary oxidation on the lignite organic mass from Kharanorsk and Kangalas deposits by different chemical reagents to determine a degree of this process impact on the efficiency of their processing into humic substances. Inorganic and organic oxidizers of different concentrations were used as reagents. The greatest effect for increasing the humic acids yield was observed when using 6-10 % hydrogen peroxide for oxidation, and 10 % hydrochloric acid. The results of experiments on the coal preoxidation effect can be used as a basis for the development of a new method of lignites processing into humic substances.

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Tamminen, Jussi, Tuomo Sainio e Erkki Paatero. "Intensification of metal extraction with high-shear mixing". Chemical Engineering and Processing: Process Intensification 73 (novembre 2013): 119–28. http://dx.doi.org/10.1016/j.cep.2013.08.005.

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7

Danylenko, V. A. "Technological Complex for Intensification of Energy Bearers Extraction". Nauka ta innovacii 2, n. 5 (30 settembre 2006): 34–40. http://dx.doi.org/10.15407/scin2.05.034.

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Kashyap, Piyush, Charanjit Singh Riar e Navdeep Jindal. "Intensification of Polyphenols Extraction from Sohiong (Prunus nepalensis) using Microwave-Assisted Extraction". Asian Journal of Chemistry 34, n. 1 (2021): 140–46. http://dx.doi.org/10.14233/ajchem.2022.23469.

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Microwave-assisted extraction (MAE) was investigated to extract polyphenols from sohiong (Prunus nepalensis) fruit. The effect of process variables (solvent concentration, solvent-solid ratio, microwave power and time) on yield and total phenol content (TPC) of fruit extract were studied using response surface methodology. The best conditions for extraction of polyphenolic extract were solvent concentration (55.17%), solvent-solid ratio (26.09%), microwave power (500 W) and time (238 s). Under optimized MAE conditions, the yield, TPC, DPPH and FRAP of sohiong extracts were 47.25%, 146.61 mgGAE/g, 89.02% and 0.58 mgAAE/g, respectively. Furthermore, MAE showed higher yield, TPC and antioxidant activity as compared to conventional solvent extraction (CSE) (28.13%, 96.56 mgGAE/g, 74.87% (DPPH) and 0.54 mgAAE/g (FRAP)), respectively. Thus, MAE is a potential alternative for polyphenols extraction from sohiong fruit and as a rich source of antioxidant compounds, it can be a potent ingredient for pharmaceuticals and food industries.

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Alexandre, Agostinho M. R. C., Ana A. Matias, Maria Rosário Bronze, Maria Jose Cocero e Rafael Mato. "Phenolic Compounds Extraction of Arbutus unedo L.: Process Intensification by Microwave Pretreatment". Processes 8, n. 3 (5 marzo 2020): 298. http://dx.doi.org/10.3390/pr8030298.

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Arbutus unedo L., commonly known as the strawberry-tree fruit, is an endemic species of the Mediterranean flora. Microwave extraction technology has been considered as a fast and “green” method for the production of extracts rich in bioactive compounds, although the energy consumption is high. To overcome this bottleneck, microwave was used as a pretreatment procedure in short time periods. This technique promotes the burst of intracellular vacuoles leading to an increase in the lixiviation of phenolic compounds. Different approaches were tested, namely a solvent-free irradiation (SFI), a solvent-assisted irradiation (SAI) and a pressurized solvent-assisted irradiation (PSAI). After irradiation, a solid–liquid extraction procedure was performed using a mixture of water and ethanol. A kinetic evaluation of the total phenolic content (TPC) was performed using the Folin–Ciocalteu method. For the total anthocyanin content, a UV-spectrophotometric method was used. HPLC-UV and LC-MS were used for TPC and identification of present compounds. Microwave irradiation led to an increase in TPC of extracts after SAI (52%) and PSAI (66%) along with a reduction in time of extraction from 30 min to less than 2 min. The anthocyanin content also increased by 66% for the SAI and PSAI extractions.

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Smelcerovic, Andrija, Sinisa Djordjevic, Zika Lepojevic e Dragan Velickovic. "The analysis of the kinetics of extraction of resinoids and hypericines from the amber, Hypericum perforatum L". Journal of the Serbian Chemical Society 67, n. 6 (2002): 457–63. http://dx.doi.org/10.2298/jsc0206457s.

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The kinetics of the extraction of the overall extracted materials (resinoids), total hypericine, hypericine and pseudohypericine from amber (Hypericum perforatum L) was investigated by the procedure of maceration both with and without ultra-sound, using methanol as the extractant. It was found that the period of fast extraction with intensification of the extraction of resinoid by ultra-sound was significantly shorter (about 20 minutes) than was needed for the extraction without ultra-sound (about 5 h). Similar results were also obtained for the extraction of the other tested substances. It can be concluded that better drug exploitation can be achieved in a much shorter extraction time by intensification of the extraction using ultra-sound. By preparation of herbal material through pulverization, a significant grade of herbal tissue structure disintegration was achieved, so that turbulent mass transfer plays a dominant role in the extraction. The results show that the coefficient values of fast extraction (b) are approximately the same for all the investigated kinetics.

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Più fonti

Tesi sul tema "Extraction intensification"

1

Pfeuffer, Bernhard [Verfasser]. "Process intensification by heterogeneous reactive extraction / Bernhard Pfeuffer". Clausthal-Zellerfeld : Universitätsbibliothek Clausthal, 2012. http://d-nb.info/1021739839/34.

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Parniakov, Oleksii. "Intensification de la congélation des aliments sous l’effet des champs électriques pulsés". Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2366/document.

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Ce travail de thèse porte sur l’étude de l’effet du traitement par champs électriques pulsés (CEP) sur l’amélioration de la congélation des tissus végétaux. Pour l’ensemble de notre étude, nous avons démontré que l’effet des champs électriques pulsés est complexe. Le prétraitement entraîne une électroperméabilisation des membranes. Les analyses calorimétriques ont mis en évidence que l’électroperméabilisation conduit à une augmentation de la teneur en eau liée. Les transferts de matière entre les milieux intra et extracellulaires sont intensifiés. Cela conduit à une modification dynamique de la composition des deux compartiments au cours de la congélation. En effet, les essais réalisés sur le cryo-pressage assisté par CEP démontrent que les températures de fusion sont plus basses et que le jus récupéré est beaucoup plus concentré. Il a été constaté que le temps de congélation d’un échantillon soumis préalablement à un prétraitement par champs électriques pulsés est sensiblement plus court que celui d’un échantillon sans prétraitement. D’autre part, l’électroperméabilisation facilite les transferts de matière avec le milieu extérieur. Le prétraitement par CEP accélère notamment l’imprégnation des tissus végétaux par des cryoprotectants, l’évaporation de l’eau libre et la sublimation de l’eau congelée. Finalement, le prétraitement par champs électriques pulsés induit des modifications de la structure des échantillons, de leur composition et influence favorablement les transferts couplés de masse et d’énergie
This work is focused on the study of the effects of pulsed electric fields (PEF) on the improvement of plant tissues freezing. These studies have demonstrated that the effects of the PEF are rather complex. The PEF treatment results in membrane electro-permeabilization. Calorimetric analyses showed that the electro-permeabilization leads to an increase in bound water content. It also results in acceleration of mass transfer processes between intra- and extracellular parts of a tissue. The dynamic modification of the composition of these two parts during the freezing was observed. Experimental tests using the PEF-assisted cryo-pressing demonstrated that the melting temperatures were lower and that the extracted juice was much more concentrated as compared to untreated tissues. Moreover, the PEF-treatment allowed significant decreasing of freezing time. Furthermore, the electro-permeabilization facilitates the mass transfer with the external medium. The PEF treatment accelerates the impregnation of plant tissues by cryoprotectants, evaporation of free water and sublimation of frozen water. Finally, the treatment by PEF induces changes in the structure of the samples, their composition and positively influences both the mass and energy transfers

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3

Mündges, Jan [Verfasser]. "Investigation and Intensification of Monoclonal Antibody Purification by Aqueous Two-Phase Extraction / Jan Mündges". München : Verlag Dr. Hut, 2015. http://d-nb.info/107976805X/34.

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Allaf, Tamara. "Application de la détente instantanée contrôlée pour l'eco-extraction des produits naturels : intensification & combinaison". Thesis, Avignon, 2013. http://www.theses.fr/2013AVIG0249/document.

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Cette étude porte sur l’analyse fondamentale et expérimentale des processus d’extraction des procédés conventionnels et innovants. L’intensification de ces techniques s’est tout d’abord basée sur des approches théoriques. D’une part, nous nous sommes focalisés sur « le paradoxe » généré par l’extraction conventionnelle des huiles essentielles et les issues et solutions que la Détente Instantanée Contrôlée (DIC) ou les Micro-Ondes (MO) peuvent apporter. D’autre part, nous nous sommes intéressés à la problématique d’intensification des opérations d’extraction par solvant des composés non-volatils à partir de végétaux. La spécificité des processus diffusionnels leur donne une importance particulière en raison de la structure propre de la matière, traduisant ainsi une mauvaise aptitude technologique intrinsèque. L’amélioration de l’extraction par l’action de la DIC sur la structure de la matrice, des MO sur le chauffage et des UltraSons (US) sur la micro-agitation, permet d’envisager un couplage, de conduire à une intensification après optimisation souvent multicritères (cinétique, qualité et énergie). La DIC a été appliquée sur des feuilles de romarin et des écorces d’orange afin d’en extraire les huiles essentielles. Ce traitement a permis d’accéder à une expansion et de parvenir à une intensification de l’extraction des molécules antioxydantes. Nous avons donc procédé à une combinaison DIC/MO pour le romarin et DIC/US pour les écorces d’orange. Enfin, la cinétique de l’extraction d’huiles de colza a été intensifiée par un prétraitement DIC et étudiée à travers une modélisation dont l’un des aspects a été une diffusion de type Fick couplée à une solution de Crank
This study focuses on fundamental analysis and experimental work carried out on extraction via conventional and innovative processes. The intensification of these techniques is first based on theoretical approaches. On the one hand, we focused our meditation on examining the "paradox" generated by conventional steam-distillation of essential oils, and suggested solutions from Instant Controlled Pressure Drop (DIC) or Microwave (MW). On the other hand, we were interested in the problematic of solvent extraction operations of plant-based non-volatile compounds. The specificity of the diffusional process gives them a special importance because of the specific structure of the material, reflecting poor intrinsic technological ability. Improving extraction by letting DIC act on the structure of the matrix, MW on heating, and UltraSound (US) on the micro-agitation, allows to coupling technologies leading to a perfect intensification and thus multi-criteria optimization (kinetics, quality and energy). DIC was applied to the leaves of rosemary and orange peel to extract essential oils. This treatment has access to expansion and to achieve increased extraction of antioxidant molecules. We therefore conducted a combination DIC/MW for rosemary and DIC/US for orange peel. Finally, the extraction kinetics of rapeseed oil has been intensified by DIC pretreatment. This kinetics was identified through modeling including Fick diffusion coupled to a Crank solution

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Li, Ying. "Les huiles végétales comme solvants alternatifs pour l’éco-extraction des produits naturels". Thesis, Avignon, 2014. http://www.theses.fr/2014AVIG0254.

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L’éco extraction apparaisse depuis quelques années comme une nouvelle tendance en matière de technique de valorisation des ressources naturelles. Avec une préoccupation de plus en plus importante concernant la sécurité, la santé mais également l’environnement, l’utilisation d’huiles végétales en tant que solvant alternatifs a été envisagée dans ce travail pour réaliser l’extraction de substances naturelles. Divers composés, avec des propriétés plus ou moins polaires ont été extrait à partir d’une sélection très variée d’huiles végétales.Dans un premier temps, la solubilité de composés aromatiques a été étudiée, de manière originale, grâce à une modélisation théorique des paramètres de solubilités de Hansen. Puis, des études expérimentales ont été réalisées afin de conforter cette approche. Des analyses statistiques permirent d’établir un classement selon le pouvoir solvant de ces derniers, ce qui nous a permis de sélectionner la meilleure huile pour l’extraction des composés aromatiques. Nous nous sommes également inspirés de la théorie du paradoxe polaire, pour réaliser l’extraction de composés phénoliques à l’aide d’huiles végétales. A ce stade, l’addition appropriée de tensioactifs; pourrait permettre d’augmenter significativement l’efficacité de l’extraction des composés cibles ce qui a été analysé de manière plus poussée afin de mettre en évidence l’effet des tensioactifs sur la structure supramoléculaire des huiles végétales. Pour terminer ce travail, l’extraction des caroténoïdes a été intensifiée à l’aide des ultrasons, tout en utilisant l’huile de tournesol comme solvant. Ce procédé optimal a été comparé au procédé conventionnel en termes de temps, de rendement mais également d’impacts environnementaux
The green extraction has arisen as a new trend in the valorisation of natural resources. As the growing concern on thesafety, health and environment, vegetable oils as alternative solvents have drawn great interests in the green extractionof bioactive compounds from nature plants. Apart from lipophilic carotenoids in this work., compounds with more polarproperties have been initially studied.Firstly, the solubility of major volatile aroma compounds in various vegetable oils was originally investigated through atheoretical modelling of their Hansen solubility parameters, followed by real experimental extractions for verification.Multivariate statistical analyses assisted to classify the solvent power of these oil solvents so as to select the optimal oil.Secondly, the revisit of polar paradox theory inspired us to achieve direct extraction of phenolic compounds usingvegetable oils as solvents. The appropriate addition of surfactants could significantly increase the extraction efficiency.The small angle X-ray scatting helped to further study the effect of surfactants on the supramolecular structure of thevegetable oils. Lastly, the extraction of carotenoids was intensified with the integration of ultrasounds and sunflower oilas the substitute to organic solvents, in which the optimized procedure has been compared with the conventional organicsolvent extraction in terms of procedures, kinetics, yields and environmental impacts

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Кутняк, М. М., e І. В. Коц. "Устаткування з гідроімпульсним приводом для інтенсифікації отримання екстрактів із заморожених плодів та ягід". Thesis, ВНТУ, 2018. http://ir.lib.vntu.edu.ua//handle/123456789/24316.

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Виконано дослідження по встановленню перспективних способів, принципових та конструктивних рішень для інтенсифікації отримання екстрактів із заморожених плодів та ягід, запропонована нова конструкція екстрактора з гідроімпульсним приводом.
The research to establish perspective methods, principle and structural decisions for the intensification of obtaining extracts from frozen fruits and berries, , a new design of an extractor with a hydropulse drive was proposed

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Boussetta, Nadia. "Intensification de l'extraction des polyphénols par électrotechnologies pour la valorisation des marcs de champagne". Compiègne, 2010. http://www.theses.fr/2010COMP1899.

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Cette étude porte sur l’amélioration de l’extraction des polyphénols à partir des marcs de raisin par des électrotechnologies : les décharges électriques de haute-tension (DEHT) et les champs électriques pulsés (CEP). Ces techniques permettent d’endommager les membranes et/ou parois cellulaires facilitant ainsi la libération du contenu intracellulaire vers le milieu extérieur. Le procédé global d’extraction développé se compose d’une diffusion aqueuse ou hydro-alcoolique assistée par un prétraitement électrique (CEP ou DEHT), suivie d’une étape de purification par extraction sur phase solide, et d’un séchage par lyophilisation. L’étude de l’effet des paramètres opératoires pour chacune de ces étapes a permis d’optimiser le procédé afin d’obtenir des poudres riches en polyphénols antioxydants. L’utilisation d’un prétraitement électrique a ainsi permis d’extraire jusqu’à 10 fois plus de polyphénols. Des essais réalisés à l’échelle semi-pilote ont confirmé l’efficacité des DEHT sur l’amélioration de l’extraction des polyphénols. La méthode d’extraction étudiée a aussi été appliquée sur chaque constituant du marc de raisin (pellicules, rafles et pépins). Ces travaux ont également mis en évidence l’impact de l’onde de choc produite lors des DEHT sur la fragmentation du produit et donc sur l’extraction des composés. Enfin, les cinétiques d’extraction des polyphénols ont pu être modélisées par le modèle empirique de Peleg et le modèle théorique de Fick afin d’estimer les rendements d’extraction au cours du temps
This study is about the intensification of the polyphenols extraction from grape pomace by electrotechnologies: high voltage electrical discharges (HVED) and pulsed electric fields (PEF). These techniques can damage cell membranes and/or cell wall thus enhancing the release of intracellular compounds. The developed extraction process is divided into three steps: an electrically assisted aqueous or hydro-ethanolic diffusion, a purification process by solid phase extraction, and a drying process (by freeze-drying). The optimization study of the main operating parameters for each process resulted in the production of a powder rich in antioxydant polyphenols. The application of an electrical pretreatment allowed increasing up to 10 times the extraction yields of polyphenols. Experiments performed at the semi-pilot scale have confirmed the positive effect of HVED on polyphenols extraction improvement. It was possible to apply this extraction method on each grape pomace component (skins, seeds and stems). Results have also shown the effect of the high pressure wave produced during HVED on the product fragmentation that increases the extraction of interest compounds. Finally, the kinetics of polyphenols have been described by the empirical Peleg’s model and the theoretical Fick’s model in order to estimate the polyphenols yields at a desired time

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Clion, Valentin. "Production d’hydrogène par fermentation obscure : intensification du procédé par extraction des gaz et développement d’un bioréacteur à membrane". Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAF024.

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Dans le contexte du développement de l’hydrogène-énergie, de nouvelles voies de production renouvelables sont étudiées, parmi lesquelles la fermentation obscure est un processus biologique convertissant la biomasse. Dans cette étude, ce procédé a été optimisé en réacteur agité semibatch par la sélection de cultures mixtes (boues de station d’épuration) et l’optimisation des paramètres de fermentation associés (température, ajout de substrat, régulation du pH). La présence majoritaire de bactéries du genre Clostridium a été observée dans le milieu fermentaire. Différents modes d’extraction des gaz produits ont été évalués, permettant d’intensifier le procédé par l’utilisation d’un gaz de balayage (N2 ou CO2). La mise en œuvre efficace en fonctionnement continu d’un bioréacteur membranaire dans une configuration d’extraction gaz/liquide a permis d’améliorer le rendement (> + 90%) et la productivité en H2 (> + 300%) par rapport au mode de fonctionnement continu en réacteur agité. Enfin, l’utilisation d’un substrat réel (bourbes viticoles) a permis de prouver la faisabilité du procédé dans une perspective d’industrialisation
In the context of the development of hydrogen-energy, new renewable production ways are studied, among which dark fermentation is a biological process converting the biomass. In this study, this process was optimized for a semibatch reactor by the selection of mixed cultures (waste water treatment plant sludges) and the optimization of associated parameters of fermentation (temperature, add of substrate, pH regulation). The presence in majority of bacteria from the genus Clostridium was observed in the fermentation broth. Different extraction modes of the produced gas were evaluated, allowing to intensify the process by the use of a sparging gas (N2 or CO2). The successful implementation in continuous mode of a membrane bioreactor in a configuration of gas/liquid extraction allowed an increase in H2 yield (> + 90%) and productivity (> + 300%) compared to the continuous stirred tank reactor. Finally, the use of a real substrate (winery waste) allowed to prove the feasibility of this process in the prospect of industrialization

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Issaadi-Hamitouche, Tassadit. "Etude de l’autovaporisation instantanée dans l’intensification de l’extraction de l’huile essentielle du bois de santal". Thesis, La Rochelle, 2016. http://www.theses.fr/2016LAROS017.

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La présente étude porte sur l’analyse fondamentale et expérimentale des procédés d’extraction des volatils. Les méthodes conventionnelles d’hydrodistillation et d’entrainement à la vapeur dans l’extraction des composés volatils (huiles essentielles…), impliquent une cinétique ralentie voire bloquée par « le processus paradoxal ». Ce dernier est dû au couplage de la génération interne de vapeur impliquant deux transferts couplés de vapeur (par diffusion) et de chaleur (par conduction). Ces deux transferts sont alors dirigés de la surface d’échange vers l’intérieur. Seul un processus de transfert partiel de la vapeur par front progressif assure l’évolution du processus. La cinétique est ainsi inévitablement lente, générant un niveau élevé de consommation d’énergie et induisant une dégradation potentielle de la matière extraite. Pour faire face à cette situation, une modification du type de transfert est essentielle. Nous avons opté pour un transfert de type Darcy au lieu du transfert de Fick, soit un gradient de pression totale au lieu du gradient de pression partielle comme « driving force ». Nous avons ainsi choisi la Détente Instantanée Contrôlée DIC comme procédé générant, suite à la détente vers le vide, une autovaporisation instantanée couplée à un grand gradient de pression totale de l’intérieur du matériau vers le milieu environnant sous vide. La détente instantanée contrôlée (DIC) a été étudiée, selon la méthodologie des plans d’expériences dans le but d’évaluer l’impact des variables opératoires sur l’extraction et de définir les paramètres optimums. Le nombre de cycles et le temps de traitement ont été pris comme paramètres indépendants. Ces paramètres sont appropriés pour représenter les aspects mécaniques et thermiques du processus DIC. L’extraction directe de l’huile essentielle du bois de santal par DIC-MP, gérée essentiellement par le nombre de cycles, indépendamment du temps de traitement, est une autovaporisation des composés volatils. Cette nouvelle méthode a ensuite été comparée tout au long de sa mise en application à l’hydrodistillation. Alors que la méthode traditionnelle d’extraction de l’huile essentielle du bois de santal requiert 140 h, l’optimisation de la DIC nous a permis de réaliser l’extraction en seulement 6 minutes, avec des rendements pratiquement similaires. Dans un dernier temps, une approche écologique et une compréhension du phénomène mis en jeu pour l’extraction des huiles essentielles par DIC ont été abordées. La rapidité de la procédure, la réduction du coût énergétique et le bon impact environnemental font de la DIC une technique industrielle particulièrement innovante et hautement attrayante
This study focuses on fundamental analysis and experimental work carried out on extraction via conventional and innovative processes. The extraction of volatile compounds (essential oils ...) through hydrodistillation or steam distillation as conventional methods is slowed or even blocked because of "the paradoxical process". The latter is due to the coupling of vapor and heat transfers, both directed from the exchange surface towards product core. Only partial vapor transfer by progressive forehead ensures the evolution of the process. The kinetics is so inevitably slow, implying high energy consumption and inducing a high degradation of both extracted and residual material. To face this situation, changing the nature of the transfer is essential. We considered the total pressure gradient instead of the vapor pressure gradient as "driving force". Instant Controlled Pressure Drop DIC was used. Instant releasing of high pressure/high pressure towards a vacuum leads to instant autovaporisation, implying a Darcy-type transfer of vapor within the material to the surrounding medium vacuum. Instant Controlled Pressure Drop (DIC) was investigated, according to the Response surface methodology RSM in order to evaluate the impact of process variables on the extraction and to define the optimal settings. The number of treatment cycles and treatment time were taken as independent parameters. These parameters were appropriated to represent both mechanical and thermal impacts of DIC process. Direct extraction of the essential oil of sandalwood DIC-MP, managed primarily by the number of cycles, regardless of treatment time, is an autovaporization of volatile compounds. This new method was then compared throughout its application to steam distillation. While traditional extraction method requires 140 hours, optimized DIC allowed performing essential oil extraction of sandalwood in only 6 minutes, with substantially similar yields. Finally, environment approach and understanding of the phenomena involved in DIC extraction of essential oils were addressed. By dramatically reducing the treatment time and the energy consumption, DIC is a particularly innovative, exceptionally effective and highly attractive environment-friendly essential oil extraction technique

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Zeaiter, Amal. "Intensification par détente instantanée contrôlée (DIC) de la fonctionnalisation physico-chimiques [sic] des graines végétales (caroube et tournesol)". Thesis, La Rochelle, 2018. http://www.theses.fr/2018LAROS011/document.

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La présente thèse traite, au travers d’une analyse fondamentale et expérimentale, l’effet de texturation par détente instantanée contrôlée (DIC) sur les phénomènes de transfert au cours des processus de séchage, d’extraction mécanique et de comportement rhéologique. Les produits concernés ont été les graines de caroube (gomme et germe) et deux variétés de graines de tournesol (linoléique et oléique). La texturation DIC permet d’agir sur la cinétique de séchage par flux d’air ce qui conduit à une intensification des processus de séchage par flux d’air tout en assurant une bonne préservation de la qualité nutritionnelle du produit fini. L’étude expérimentale a été couplée à une analyse phénoménologique de la cinétique à travers une modélisation de type CWD (coupled Washing/Diffusion). Cette dernière étude conduit à une évaluation de l’impact de la texturation sur la diffusivité effective Deff et l’accessibilité initiale δWs. D’autre part, l’étude expérimentale en vue de l’optimisation de l’opération a été réalisée à travers la méthode des plans d’expériences. La modification des paramètres opératoires fonctionnels de la DIC, à savoir la pression absolue de vapeur d’eau saturée sèche (P), et le temps de traitement thermique (t), ainsi que le nombre des cycles (c) sur l’ensemble des performances de l’opération a été établie sur le comportement rhéologique de la gomme de caroube. Une deuxième partie de la thèse a été consacrée à l’étude fondamentale et expérimentale des procédés d’extraction d’huile de tournesol des deux variétés de graines linoléiques et oléiques. Le traitement thermomécanique par détente instantanée contrôlée (DIC) permet, à travers une modification contrôlée de la structure de la matière première, d’agir sur l’extraction mécanique par presse à froid des huiles de tournesol, ainsi que sur l’extraction par solvant de l’huile à partir du tourteau résiduel. Un complément à cette opération a consisté en l’extraction par solvant (n-hexane) opérée sur l’ensemble des graines de tournesol. La texturation DIC a conduit à une grande augmentation du rendement en huile pour les variétés linoléique et oléique. La préservation de la qualité de l’huile et du tourteau prouve l’adéquation de la DIC avec l’absence pratique de la dégradation chimique. Notre étude a également concerné la définition d’un nouveau procédé de désodorisation. Il s’agit de l’utilisation de l’Autovaporisation Multi-Flash MFA sur le raffinage de l’huile de tournesol. Cette technologie innovante de désodorisation se distingue par son faible niveau de température assurant ainsi une sévérité nettement inférieure à celle des méthodes conventionnelles à haute température
This thesis deals with a fundamental and experimental analysis of the effect of instant controlled pressure drop (DIC) on the transfer phenomena and rheological behavior, which occurs during the drying process and mechanical and solvent extraction. The products concerned were carob seeds (gum and germ) and two varieties of sunflower seeds (linoleic and oleic). DIC texturing makes it possible to greatly modify the drying kinetics, leading to an effective intensification of the drying processes while maintaining a good preservation of the nutritional quality of the finished product. The experimental study was coupled with a phenomenological kinetic model using the CWD (coupled Washing/Diffusion). This study leads to evaluate the impact of texturing on the effective diffusivity Deff and the initial accessibility δWs. On the other hand, the experimental study for the optimization of the operation was carried out through an adequate experimental design method. The impact of the DIC processing parameters, namely the absolute pressure of saturated dry water vapor (P), and the heat treatment time (t), as well as the number of cycles (c) was established on the rheological behavior of the carob bean gum. A second part of our work was devoted to the theoretical and experimental study of sunflower oil extraction processes of the two types of linoleic and oleic seeds. By acting as a controlled modification of the raw material, (DIC) texturing allowed increasing the yield of sunflower oil by both cold pressing and solvent extraction from the residual cake. DIC texturing has led to a large increase in oil yield for both linoleic and oleic varieties. The preservation of the quality of oil demonstrates that DIC was perfectly adequate with a perfect absence of chemical degradation. Our study also involved the definition of a new deodorization process. This is the use of the Multi-Flash Autovaporization MFA on the refining of sunflower oil. This innovative deodorization technology is characterized by its low temperature level, thus ensuring a much lower severity than conventional high temperature methods

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Libri sul tema "Extraction intensification"

1

Juliano, Pablo, Kai Knoerzer e Geoffrey W. Smithers. Innovative Food Processing Technologies: Extraction, Separation, Component Modification and Process Intensification. Elsevier Science & Technology, 2016.

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Juliano, Pablo, Kai Knoerzer e Geoffrey W. Smithers. Innovative Food Processing Technologies: Extraction, Separation, Component Modification and Process Intensification. Elsevier Science & Technology, 2023.

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Juliano, Pablo, Kai Knoerzer e Geoffrey W. Smithers. Innovative Food Processing Technologies: Extraction, Separation, Component Modification and Process Intensification. Elsevier Science & Technology, 2016.

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Innovative Food Processing Technologies: Extraction, Separation, Component Modification and Process Intensification. Elsevier Science & Technology, 2023.

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Capitoli di libri sul tema "Extraction intensification"

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Lee, Keat T., e Steven Lim. "Reactive Extraction Technology". In Process Intensification for Green Chemistry, 275–87. Chichester, UK: John Wiley & Sons, Ltd, 2013. http://dx.doi.org/10.1002/9781118498521.ch10.

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Kiss, Anton Alexandru. "Reactive Extraction Technology". In Process Intensification Technologies for Biodiesel Production, 77–86. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-03554-3_7.

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de Haan, André B., e Snehal D. Birajdar. "CHAPTER 5. Liquid–Liquid Extraction in Processing of Bioproducts". In Intensification of Biobased Processes, 109–31. Cambridge: Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/9781788010320-00109.

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Brandenbusch, Christoph, Tim Zeiner e Juliane Merz. "CHAPTER 16. Intensification of Aqueous Two-phase Extraction for Protein Purification". In Intensification of Biobased Processes, 344–64. Cambridge: Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/9781788010320-00344.

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Allaf, Tamara, e Karim Allaf. "Fundamentals of Process-Intensification Strategy for Green Extraction Operations". In Green Extraction of Natural Products, 145–72. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2015. http://dx.doi.org/10.1002/9783527676828.ch5.

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Turk, Mohammad, Sandrine Perino, Emmanuel Petitcolas e Farid Chemat. "CHAPTER 18. Microwave-enhanced Extraction of Natural and Food Products: from Academia to Innovative and Large-scale Applications". In Intensification of Biobased Processes, 381–96. Cambridge: Royal Society of Chemistry, 2018. http://dx.doi.org/10.1039/9781788010320-00381.

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Gogate, Parag R., e Saurabh M. Joshi. "Process Intensification Aspects of Extraction of Pigments from Microalgae". In Pigments from Microalgae Handbook, 309–24. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-50971-2_13.

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Pérez, Izaskun, Carlos Bald, Íñigo Martínez de Marañón e Karim Allaf. "DIC Intensification of the Mechanical Extraction of Lipids by Pressing". In Food Engineering Series, 163–76. New York, NY: Springer New York, 2013. http://dx.doi.org/10.1007/978-1-4614-8669-5_9.

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Alzorqi, Ibrahim, e Sivakumar Manickam. "Ultrasonic Process Intensification for the Efficient Extraction of Nutritionally Active Ingredients of Polysaccharides from Bioresources". In Handbook of Ultrasonics and Sonochemistry, 1–16. Singapore: Springer Singapore, 2015. http://dx.doi.org/10.1007/978-981-287-470-2_65-1.

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Alzorqi, Ibrahim, e Sivakumar Manickam. "Ultrasonic Process Intensification for the Efficient Extraction of Nutritionally Active Ingredients of Polysaccharides from Bioresources". In Handbook of Ultrasonics and Sonochemistry, 1271–86. Singapore: Springer Singapore, 2016. http://dx.doi.org/10.1007/978-981-287-278-4_65.

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Atti di convegni sul tema "Extraction intensification"

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FEI, WEIYANG. "INTENSIFICATION OF EXTRACTION COLUMNS VIA CFD SIMULATION AND ADVANCE MEASUMENT TECHNIQUES". In Proceedings of the 4th International Conference. WORLD SCIENTIFIC, 2004. http://dx.doi.org/10.1142/9789812702623_0001.

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Averyanova, Elena V., Marina N. Shkolnikova, Sergey N. Tsyganok e Vladislav A. Shakura. "Intensification of the Process of Ultrasonic Extraction of Dehydroquercetin from Wood Waste". In 2018 19th International Conference of Young Specialists on Micro/Nanotechnologies and Electron Devices (EDM). IEEE, 2018. http://dx.doi.org/10.1109/edm.2018.8435055.

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MILOUDI, Kaddour, Amar TILMATINE, Youcef BENMIMOUN, Abderrahmane HAMIMED, Ahmed TAIBI e Yacine BELLEBNA. "Intensification of Essential Oil Extraction of Artemisia herba alba Using Pulsed Electric Field". In 2018 International Conference on Electrical Sciences and Technologies in Maghreb (CISTEM). IEEE, 2018. http://dx.doi.org/10.1109/cistem.2018.8613580.

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Krivošija, Slađana, Zorana Mutavski, Senka Vidović e Nataša Nastić. "Intensification of anthocyanin extraction from Sambucus nigra fruits using ultrasonic probe". In IV. Symposium of Young Researchers on Pharmaceutical Technology,Biotechnology and Regulatory Science. Szeged: Institute of Pharmaceutical Technology and Regulatory Affairs, University of Szeged, Faculty of Pharmacy, 2022. http://dx.doi.org/10.14232/syrptbrs.2022.39.

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Muller, Christopher, Ali Khadir, Amr Abdelrahman, Ahmed Al-Omari, Eunkyung Jang, Katherine Bell, John Norton, Chris Sheculski, Domenico Santoro e George Nakhla. "Application of Vacuum Extraction to Anaerobic Digestion for Process Intensification and Resource Recovery". In WEFTEC 2024. Water Environment Federation, 2024. http://dx.doi.org/10.2175/193864718825159715.

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Rudobashta, Stanislav P. "Efficiency of mass exchange processes in systems with solid phase (drying, adsorption, extraction)". In INTERNATIONAL SCIENTIFIC-TECHNICAL SYMPOSIUM (ISTS) «IMPROVING ENERGY AND RESOURCE-EFFICIENT AND ENVIRONMENTAL SAFETY OF PROCESSES AND DEVICES IN CHEMICAL AND RELATED INDUSTRIES». The Kosygin State University of Russia, 2021. http://dx.doi.org/10.37816/eeste-2021-p-80-88.

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On specific examples, the possibilities of increasing the efficiency (in the broad sense of the word) of the specified mass transfer processes at the present stage are considered - through the use of modern methods of mathematical modeling and kinetic calculation of devices, intensification, energy and resource conservation, preservation or even improvement of the quality indicators of processed materials, solutions to environmental

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Shumilova, L. V., K. K. Razmakhnin e A. N. Khatkova. "EXTRACTION OF GOLD FROM TECHNOGENIC RAW MATERIALS WITH PRELIMINARY OXIDATION OF CARBONACEOUS SUBSTANCES". In XVI INTERNATIONAL CONFERENCE "METALLURGY OF NON-FERROUS, RARE AND NOBLE METALS" named after corresponding member of the RAS Gennady Leonidovich PASHKOVA. Krasnoyarsk Science and Technology City Hall, 2023. http://dx.doi.org/10.47813/sfu.mnfrpm.2023.47-58.

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In accordance with the state policy of the innovative development path of Russia and the tightening of requirements for the introduction of the best available technologies that ensure the possibility of compromise coexistence of two systems: human nature, human technology, it becomes necessary to develop environmentally friendly methods for leaching gold. Therefore, the search for a substitute of aggressive cyanide for lowtoxic solvents using the intensification methods of the process in order to fully extract the noble metal is an urgent scientific task.

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Razumov, Evgeny. "INTENSIFICATION OF WATER EXTRACTION PROCESS OF CHAGA BY MEANS OF RECURRENT PRESSURE REDUCTION OF THE MEDIA". In 18th International Multidisciplinary Scientific GeoConference SGEM2018. Stef92 Technology, 2018. http://dx.doi.org/10.5593/sgem2018/3.2/s14.107.

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Safin, Ruslan, Shamil Mukhametzyanov, Albina Safina, Nour Galyavetdinov e Valeriy Gubernatorov. "RESEARCH OF THE INFLUENCE OF THE MODE PARAMETERS OF THE WATER-VACUUM EXTRACTION PROCESS ON THE YIELD OF BIOLOGICALLY ACTIVE SUBSTANCES INONOTUS OBLIQUUS". In GEOLINKS Conference Proceedings. Saima Consult Ltd, 2021. http://dx.doi.org/10.32008/geolinks2021/b1/v3/19.

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Inonotus obliquus or chaga birch mushroom has a fairly wide range of applications in the cosmetic, food and pharmaceutical industries due to the wide range of biologically active substances it contains. The analysis of foreign and domestic studies testifies to the ongoing research in the field of extraction of valuable components from chaga, however, issues of intensification of processes and the development of new methods of extraction remain topical. One of these methods is the water-vacuum extraction of chaga, which consists in alternating the stages of the process at atmospheric and reduced pressure. The aim of the study is to determine the optimal time parameters of the individual stages of the water-vacuum extraction of chaga to optimize the operating parameters of the process. The object of the study was chaga collected in forest plantations in central Russia in the spring season, and crushed to particles ranging in size from 0.1 to 1.2 mm. The experiments were carried out on a laboratory version of a vacuum extraction unit, which allows for the classical infusion and extraction of chaga at various variations in the pressure of the medium. Studies have shown that preliminary evacuation of dry raw materials and the introduction of a rarefied medium into the process of water extraction of chaga makes it possible to intensify the extraction process and has a positive effect on the yield and activity of extractive substances. It has been established that the preliminary evacuation of crushed chaga makes it possible to increase the efficiency of subsequent extraction and to increase the yield of valuable components by 15-18%. The optimal time for this stage was 5 minutes. The effective duration of the infusion step at atmospheric pressure was 30 minutes, and the subsequent evacuation is expediently carried out for 10 minutes. Based on the results of the presented work, the optimal scheme for carrying out the process of water-vacuum extraction of chaga was determined.

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Averyanova, Elena V., Marina N. Shkolnikova, Sergey N. Tsyganok e Vladislav A. Shakura. "The Intensification of the Water Extraction of the Cinnamon Rose Hips under the Conditions of Ultrasonic and Microwave Actions". In 2019 20th International Conference of Young Specialists on Micro/Nanotechnologies and Electron Devices (EDM). IEEE, 2019. http://dx.doi.org/10.1109/edm.2019.8823176.

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Rapporti di organizzazioni sul tema "Extraction intensification"

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Mena Benavides, Melisa, Caitlyn Eberle e Liliana Narvaez. Technical Report: Groundwater depletion. United Nations University - Institute for Environment and Human Security (UNU-EHS), ottobre 2023. http://dx.doi.org/10.53324/cuaa8911.

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Around 30 per cent of the world’s freshwater is stored as groundwater, often used for drinking water and crop irrigation. A balance between extraction and recharge is critical to maintain stable water levels and ensuring a reliable supply for irrigation and drinking water. However, many global groundwater resources are being depleted faster than they can recharge. Accelerated extraction rates, particularly from agricultural intensification, are putting groundwater resources and the systems that depend on them at risk. This technical background report for the 2023 edition of the Interconnected Disaster Risks report analyses the root causes, drivers, impacts and potential solutions for the groundwater depletion risk tipping point our world is facing through an analysis of academic literature, media articles and expert interviews.

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Stall, Nathan M., Kevin A. Brown, Antonina Maltsev, Aaron Jones, Andrew P. Costa, Vanessa Allen, Adalsteinn D. Brown et al. COVID-19 and Ontario’s Long-Term Care Homes. Ontario COVID-19 Science Advisory Table, gennaio 2021. http://dx.doi.org/10.47326/ocsat.2021.02.07.1.0.

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Key Message Ontario long-term care (LTC) home residents have experienced disproportionately high morbidity and mortality, both from COVID-19 and from the conditions associated with the COVID-19 pandemic. There are several measures that could be effective in preventing COVID-19 outbreaks, hospitalizations, and deaths in Ontario’s LTC homes, if implemented. First, temporary staffing could be minimized by improving staff working conditions. Second, homes could be further decrowded by a continued disallowance of three- and four-resident rooms and additional temporary housing for the most crowded homes. Third, the risk of SARS-CoV-2 infection in staff could be minimized by approaches that reduce the risk of transmission in communities with a high burden of COVID-19. Summary Background The Province of Ontario has 626 licensed LTC homes and 77,257 long-stay beds; 58% of homes are privately owned, 24% are non-profit/charitable, 16% are municipal. LTC homes were strongly affected during Ontario’s first and second waves of the COVID-19 pandemic. Questions What do we know about the first and second waves of COVID-19 in Ontario LTC homes? Which risk factors are associated with COVID-19 outbreaks in Ontario LTC homes and the extent and death rates associated with outbreaks? What has been the impact of the COVID-19 pandemic on the general health and wellbeing of LTC residents? How has the existing Ontario evidence on COVID-19 in LTC settings been used to support public health interventions and policy changes in these settings? What are the further measures that could be effective in preventing COVID-19 outbreaks, hospitalizations, and deaths in Ontario’s LTC homes? Findings As of January 14, 2021, a total of 3,211 Ontario LTC home residents have died of COVID-19, totaling 60.7% of all 5,289 COVID-19 deaths in Ontario to date. There have now been more cumulative LTC home outbreaks during the second wave as compared with the first wave. The infection and death rates among LTC residents have been lower during the second wave, as compared with the first wave, and a greater number of LTC outbreaks have involved only staff infections. The growth rate of SARS-CoV-2 infections among LTC residents was slower during the first two months of the second wave in September and October 2020, as compared with the first wave. However, the growth rate after the two-month mark is comparatively faster during the second wave. The majority of second wave infections and deaths in LTC homes have occurred between December 1, 2020, and January 14, 2021 (most recent date of data extraction prior to publication). This highlights the recent intensification of the COVID-19 pandemic in LTC homes that has mirrored the recent increase in community transmission of SARS-CoV-2 across Ontario. Evidence from Ontario demonstrates that the risk factors for SARS-CoV-2 outbreaks and subsequent deaths in LTC are distinct from the risk factors for outbreaks and deaths in the community (Figure 1). The most important risk factors for whether a LTC home will experience an outbreak is the daily incidence of SARS-CoV-2 infections in the communities surrounding the home and the occurrence of staff infections. The most important risk factors for the magnitude of an outbreak and the number of resulting resident deaths are older design, chain ownership, and crowding. Figure 1. Anatomy of Outbreaks and Spread of COVID-19 in LTC Homes and Among Residents Figure from Peter Hamilton, personal communication. Many Ontario LTC home residents have experienced severe and potentially irreversible physical, cognitive, psychological, and functional declines as a result of precautionary public health interventions imposed on homes, such as limiting access to general visitors and essential caregivers, resident absences, and group activities. There has also been an increase in the prescribing of psychoactive drugs to Ontario LTC residents. The accumulating evidence on COVID-19 in Ontario’s LTC homes has been leveraged in several ways to support public health interventions and policy during the pandemic. Ontario evidence showed that SARS-CoV-2 infections among LTC staff was associated with subsequent COVID-19 deaths among LTC residents, which motivated a public order to restrict LTC staff from working in more than one LTC home in the first wave. Emerging Ontario evidence on risk factors for LTC home outbreaks and deaths has been incorporated into provincial pandemic surveillance tools. Public health directives now attempt to limit crowding in LTC homes by restricting occupancy to two residents per room. The LTC visitor policy was also revised to designate a maximum of two essential caregivers who can visit residents without time limits, including when a home is experiencing an outbreak. Several further measures could be effective in preventing COVID-19 outbreaks, hospitalizations, and deaths in Ontario’s LTC homes. First, temporary staffing could be minimized by improving staff working conditions. Second, the risk of SARS-CoV-2 infection in staff could be minimized by measures that reduce the risk of transmission in communities with a high burden of COVID-19. Third, LTC homes could be further decrowded by a continued disallowance of three- and four-resident rooms and additional temporary housing for the most crowded homes. Other important issues include improved prevention and detection of SARS-CoV-2 infection in LTC staff, enhanced infection prevention and control (IPAC) capacity within the LTC homes, a more balanced and nuanced approach to public health measures and IPAC strategies in LTC homes, strategies to promote vaccine acceptance amongst residents and staff, and further improving data collection on LTC homes, residents, staff, visitors and essential caregivers for the duration of the COVID-19 pandemic. Interpretation Comparisons of the first and second waves of the COVID-19 pandemic in the LTC setting reveal improvement in some but not all epidemiological indicators. Despite this, the second wave is now intensifying within LTC homes and without action we will likely experience a substantial additional loss of life before the widespread administration and time-dependent maximal effectiveness of COVID-19 vaccines. The predictors of outbreaks, the spread of infection, and deaths in Ontario’s LTC homes are well documented and have remained unchanged between the first and the second wave. Some of the evidence on COVID-19 in Ontario’s LTC homes has been effectively leveraged to support public health interventions and policies. Several further measures, if implemented, have the potential to prevent additional LTC home COVID-19 outbreaks and deaths.

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