Application of Emulsion Flow for Sealing Leaky Gas Wells
Notice bibliographique
Résumé
Abstract Across Canada, thousands of abandoned gas wells leak gas to the surface. As a potential solution to this problem, we have done laboratory-scale experiments relevant to a field- tested novel process and which injects an oil-in-water emulsion through the well casing perforations to plug the cement and part of the formation near the well bore. Earlier we observed that for unconsolidated cores, the process is effective and may withstand large pressure gradients over long periods of time; however, examination of the cores showed that the emulsion broke upon entering the core and therefore did not penetrate to the desired depth. Now, we report results of subsequent experiments, our understanding of the process, and criteria for controlling the distance into the formation to which an emulsion may penetrate. In these experiments, well-characterized emulsions were injected into micro-models packed with well-sorted glass beads or sand grains to yield the desired permeability. Visualization experiments were done to observe emulsion droplets capture. We observed that, for a given pressure gradient, some droplets are too large to pass through a pore's throat (size exclusion), that other droplets attach to the pore's surface and coalesce with nearby droplets to accelerate the blockage process, and that more viscous droplets were most effective in blocking pores. We found that the rate and extent of transfer of surfactant from the solution to the beads' surface must be important. In subsequent experiments, we flushed the micro-models with surfactant solution to alter the wettability of the beads prior to injecting the emulsions. The results showed that the choice of surfactant, its concentration, and the volume of its injected solution predictably affect the depth to which the oil-in-water emulsion may penetrate into a micro-model. In conclusion, this work characterizes the flow behavior and breaking of an emulsion in a porous medium and examines parameters that may be adjusted to control the novel process. Introduction Crude oil emulsions are a broad area and several books have been written on the subject [1–3]. Their occurrence in certain modes of crude oil production and their application as a blocking agent in underground porous media have received more attention recently. Emulsions can be encountered in almost all phases of oil production and processing [4,5]. Field emulsions can be generated within oil reservoirs and/or in the well bore during production. The problem has been more pronounced recently due to the fact that many oil reservoirs are being watered out. Salty water has to be separated from the produced emulsions in order to meet crude specifications for transportation, storage, and export as well as avoid catalyst poisoning in the refineries. However, emulsion treatment is not an easy task and demands an application of various thermal, mechanical, chemical and/or electrical processes or their combination [4,5]. On the other hand, the application of emulsions as blocking agents in many secondary and tertiary oil recovery processes makes them of particular interest to many researchers.
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) | 0,000 | 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 ».