Modelling and Multi-Objective Optimization of the Sulphur Dioxide Oxidation to the Sulphur Trioxide Process
Notice bibliographique
Résumé
In this thesis, the catalytic oxidation of sulphur dioxide (SO₂) to sulphur trioxide (SO₃), which is a critical step in the production of sulphuric acid (H₂SO₄), was studied under adiabatic operating conditions. The oxidation process is taking place in a heterogeneous plug flow reactor. Because the SO₂ oxidation is a highly exothermic equilibrium reaction, a series of packed bed catalytic reactors with intercooling heat exchangers is required to achieve high SO₂ conversion. To predict the effect of the operating conditions such as the temperature and the pressure on the oxidation as well as to model mathematically the reactor, it is essential to find an appropriate kinetic rate equation. In this study, various kinetic models were evaluated to select the kinetic model that appeared to be the most representative of available experimental data. In this regard, the residual sum of squares of the differences between the predicted and experimental conversion values was used to compare the various kinetic models. The model which showed the better fitting of the experimental data was the one proposed by Collina et al. The SO₂ oxidation reactor model was developed in order to propose a methodology to perform the multi-objective optimization of many process strategies involving a number of catalytic beds and different reactor configurations. The temperature and the length of each catalytic bed are considered as decision variables to determine the optimal values of the three objectives: the SO₂ conversion, the SO₃ productivity and the catalyst weight, where the first two need to be maximized whereas the last one need to be minimized. The optimization process is comprised of two main steps. First, the Pareto domain, which contains a representative number of non-dominated solutions, was circumscribed using a non-sorting genetic algorithm. Secondly, the Pareto domain was ranked with the Net Flow method (NFM) to determine the highest-ranked Pareto-optimal solution. For ranking the Pareto domains of all strategies, a greater emphasis was placed on the SO₂ conversion because unreacted SO₂ needs to handle at the exit of the process in addition to decrease the amount of sulphuric acid produced. Results show that the process comprised of four catalytic beds with an intermediate SO₃ absorption column provides higher SO₂ conversion in comparison with the process with four catalytic beds without an intermediate absorption column. However, the enhanced conversion is achieved at the expense of higher operating costs. The optimum value of the total bed length for the four catalytic beds without an intermediate SO₃ absorption column commonly used industrially, is very closed to its minimum or ideal (5% difference), which clearly shows that the minimum catalyst weight almost prevails in this strategy to reach a relatively high SO₂ conversion in the vicinity of 97%.
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 | 0,001 |
| 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 | 0,000 |
| 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 ».