Performance of Flare Flames in a Crosswind With Nitrogen Dilution
Notice bibliographique
Résumé
Abstract Flares are used for the safe, clean, and economical disposal of waste gases, whether in upstream oil production (solution gas flares), refineries, gas plants, or other chemical processing facilities. Elevated flares are exposed to a range of weather patterns; perhaps the most important being the crosswind. The CETC Flare Test Facility (FTF) was constructed to address the question of performance of solution gas flares, in response to limited field trials that indicated the possibility of very low combustion efficiencies under certain conditions. The FTF produces crosswind speeds up to 45 km/h with very low turbulence intensity, as designed. Model solution gases are produced from natural gas, propane, inert diluents (carbon dioxide and nitrogen), and volatile liquids. Atmospheric wind is a turbulent shear flow with an intensity of around 7﹪. To more closely replicate the turbulence properties of atmospheric wind, a range of turbulence intensities and integral length scales were imposed in the FTF by using grids. The flare flame efficiency is measured by the conversion of carbon in the solution gas to carbon dioxide. Efficiency is lowest for pure natural gas, and increases with the amount of propane. Conversion efficiency decreases significantly with the increase of turbulence intensity of the crosswind, which has implications for existing and novel strategies to improve flare performance. The primary product of incomplete combustion is methane, a significant greenhouse gas. The combined effect of inert diluents and turbulence intensity on flame stability shows that turbulence amplifies the destabilizing effect of fuel dilution. Introduction Flares are used for the safe, clean, and economical disposal of waste gases, whether in upstream oil production (solution gas flares), refineries, gas plants or other chemical processing facilities. Elevated flares are exposed to all the weather patterns; perhaps the most important is the crosswind. The flaring of solution gas (also called associated gas) was a common practice in upstream oil extraction. This gas is a mixture of light hydrocarbons, mostly methane but including possibly significant amounts of ethane, propane, butane, hydrogen, perhaps some inert gases (nitrogen and carbon dioxide), and sometimes hydrogen sulphide (sour gas). The composition and amount of solution gas can vary a great deal between production sites. Over 800 million m3 of gas was flared in Alberta in 2000, which is almost a 50﹪ reduction from 1996(1). The current global flaring rate is estimated between 100 and 126 billion m3 of solution gas each year(2). Strosher(3) conducted laboratory-scale investigations on an enclosed flare and an open-air flare, and on two commercial flares in the field. He found in the field investigations that combustion efficiency is typically about 70%, sometimes as low as 62﹪. The unburned portion consisted of methane, unsaturated hydrocarbons, light aromatics such as benzene, and polycyclic aromatic hydrocarbons (PAH). This work has led to much of the current interest in flare research by industry, government, academia, and the public. An important parameter in the flare flame behaviour is the ratio of the fuel jet momentum flux to the crosswind momentum flux.
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 | 0,001 |
| 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 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 ».