Frother controlled interfacial phenomena in dynamic systems - a holistic approach
Notice bibliographique
Résumé
The development of froth flotation has revolutionized the mining industry and greatly increased the mineral production. Flotation reagents are widely applied to control the properties of minerals and bubbles in order to enhance the efficiency of froth flotation. Frothers are one of the flotation reagents employed to improve the performance of the process. The presence of frother molecules aids to reduce bubble size and rise velocity, and enhance froth stability. Although the effect of flotation frothers on bubble size is well known, the mechanism leading to the decrease in bubble size is not clearly understood. \nIn the present work, the effects of flotation frothers on bubble properties were examined in turbulent conditions. A new experimental framework was developed in order to understand the dynamic macro (> 10exp-2 m)-, meso (10exp-5 to 10exp-2 m)- and micro/nano (< 10exp-5 m)- scale phenomena affecting the bubble size in turbulent conditions. The new approach was aimed to explore the chain reaction triggered by the adsorption of surface-active agents, acting along the different size-scales and eventuating in decrease in bubble size. \nTo accomplish the aim, each and every size-scale was investigated in great detail and the results were correlated to each other. The micro/nano-scale phenomena affecting the bubble properties were investigated applying extensive dynamic surface property study such as dynamic surface tension, dynamic surface elasticity and adsorption/desorption rates. The meso-scale properties of bubbles (e.g. bubble rising velocity, bubble coalescence and breakup) were examined using newly designed experimental set-ups. The industrial or macro-scale properties of air bubbles were studied employing McGill Bubble Viewer. A series of common commercial frothers (DF200, NF240 and DF250) and two reagent grades (Pentanol and Polypropylene Glycol) were used during the study. \nThe main result of this work is a comprehensive, so far unavailable picture of the dynamics of surface-active molecules affecting bubble size in the presence of random momentum transfer. The adsorbed molecules diminish the tension at the air/liquid interface and increase its surface elasticity leading to a lower bubble rise velocity and modified coalescence and breakup properties that eventuate in smaller bubble size. The adsorption of weakly surface-active DF200 and Pentanol cause a different change in the properties of the air/liquid interface compared to the strongly surface-active DF250 and Polypropylene Glycol, leading to differences in size-scale properties and eventually in bubble size. The results help to understand the mechanism of flotation frothers and can provide information on possibilities to achieve better performance in mineral flotation by finding the most suitable surfactants for the particular process.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».