Heat of Combustion Analysis of Residual Hydrocarbon Following In Situ Combustion Tests
Notice bibliographique
Résumé
Production of Athabasca Oil Sands has always been a challenge due to its high viscosity. To produce the subsurface oil, enhanced oil recovery (EOR) is necessary. In Situ Combustion (ISC) is an EOR technique with high recovery factor but, due to the high number of reactions occurring simultaneously during application of the method, the use of computational simulators is still a challenge. Therefore, laboratory physical simulations are necessary to evaluate the viability of ISC in a specific field. These simulations are normally conducted using core samples in one-dimensional combustion tube tests to analyze the temperature profiles, pressure drops, product gas compositions and fluid production. A new 3-D physical laboratory simulator has been developed by the In Situ Combustion Research Group at the University of Calgary. The model consists of a 3-D box to evaluate ISC as a hybrid process with steam. The advantage of the 3-D model is that it provides better visualization of the process since multiple dimensional data are obtained. Post-test core samples that exhibited a significant coke bank or wall were selected from two 3-D tests which had been previously performed using cores from Athabasca Oil Sands reservoirs. Both of the 3-D tests evaluated in this research simulated a pre-production by SAGD (Steam Assisted Gravity Drainage). The 3-D boxes were packed with two distinct oil zones: Rich Zone (with a higher oil concentration) and Lean Zone (with a lower oil concentration). Lean Zone represented the area pre-produced by SAGD. After packing, the ISC process was performed with dry air (21% oxygen) injection during 3-D Test #1 and with enriched air (95% oxygen) and super-heated steam co-injection during 3-D Test #2. This current study analyzes selected samples of the post-test residual that are associated with the coke bank or coke wall in terms of the heats of combustion of residual hydrocarbon in contact with the sand, the toluene extractable oil, its fractions (maltenes and asphaltenes), as well as the toluene insoluble coke fraction remaining on the extracted core matrix. The higher O2 concentration on the injected fluid used during 3-D Test #2 might have increased the oxidation of the hydrocarbons. As a result, the heat of combustion of coke from 3-D Test #2 was found to be lower than from Test #1 (with normal air injection). Therefore, it was not possible to obtain a generalized value for the heat of combustion of coke for Athabasca Oil Sands. Coke showed to have a lower contribution to the total heat of combustion when compared to other hydrocarbon components tested (oil, maltenes and asphaltenes). For this reason, coke appears to not be the main fraction used as fuel used during In Situ combustion process. A significant finding from this study is that the residual hydrocarbon which is visually identified as the coke bank or coke wall is a mixture of maltenes, asphaltenes and toluene insoluble coke fractions. It was also observed when measuring the heat of combustion of samples that involved residual hydrocarbon plus sand that either gelatin capsules or benzoic acid was required to achieve complete combustion of the samples.
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 machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| 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 | 0,001 | 0,001 |
| 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 | 0,001 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,002 | 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 source (Gemma direct ou Codex distillé), 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 ».