Feasibility of Batch Reactive Distillation with Equilibrium-Limited Consecutive Reactions in Rectifier, Stripper, or Middle-Vessel Column.

A general overall feasibility methodology of batch reactive distillation of multireaction systems is developed to study all the possible configurations of batch reactive distillation. The general model equations are derived for multireaction system with any number of chemical equilibrium-limited reactions and for any number of components. The present methodology is demonstrated with the detailed study of the transesterification of dimethyl carbonate in two reversible cascade reactions in batch reactive distillation process. Pure methanol is produced as distillate, and pure diethyl carbonate is produced at the bottom simultaneously in middle-vessel column; in each section, continuous feeding of ethanol is necessary. The results of feasibility study are successfully validated by rigorous simulations

An application of a cocitation-analysis method to find further research possibilities on the area of scheduling problems

In this article we will give firstly a classification scheme of scheduling problems and their solving methods. The main aspects under examination are the following: machine and secondary resources, constraints, objective functions, uncertainty, mathematical models and adapted solution methods. In a second part, based on this scheme, we will examine a corpus of 60 main articles (1015 citation links were recorded in total) in scheduling literature from 1977 to 2009. The main purpose is to discover the underlying themes within the literature and to examine how they have evolved. To identify documents likely to be closely related, we are going to use the cocitation-based method of Greene et al. (2008). Our aim is to build a base of articles in order to extract the much developed research themes and find the less examined ones as well, and then try to discuss the reasons of the poorly investigation of some areas

New extractive configuration separating azeotropic mixture in semi-batch way

A new variant of batch extractive distillation, the so-called inverse-fed batch extractive distillation is presented. The total amount of the entrainer is pre-loaded to the boiler, and the mixture charge to be separated is continuously fed to the column in this novel configuration. The feasibility study of conventional extractive distillation was extended and a thorough study was performed to separate a maximum boiling azeotrope with intermediate boiling entrainer. The new configuration was found more efficient than the conventional one. The results of the feasibility study was validated and completed with a sensitivity analysis performed with commercial simulator software

Batch Extractive Distillation with Light Entrainer

Use of a light entrainer in batch extractive distillation is justified when the mixture boils at a high temperature, or when an appropriate heavy or intermediate entrainer cannot be found. Feasibility of batch extractive distillation with light entrainer for separating minimum and maximum boiling azeotropes and close boiling mixtures is studied in this article. Our test mixtures are: ethanol/water (minimum boiling azeotrope) with methanol, water/ethylene diamine (maximum boiling azeotrope) with methanol, and chlorobenzene/ethylbenzene (close boiling mixture) with 4-methylheptane. Feasibility, operating steps, limiting entrainer flows, limiting reflux ratios, and limiting number of theoretical stages are determined by parametric study on profiles maps, and verified by rigorous simulation. The effects of reflux ratio, feed ratio, feed stage, number of stages, and thermodynamic state of the entrainer are also examined. It can be established, as a result, that processes separating either minimum or maximum boiling azeotropes, or close boiling mixtures, in batch extractive distillation using a light entrainer are feasible

Etude de faisabilité de la séparation éthylenediamine – eau avec méthanol dans un stripper extractif batch

En présence d’eau (W), l’éthylène diamine (EDA) forme un mélange azéotropique de point de bulle maximum dont séparation est impossible par distillation conventionnelle. Elle peut être réalisée dans une colonne de distillation extractive inverse discontinue (BES) alimentée en continue par un solvant (méthanol (MeOH)). Le mélange à séparer est introduit dans le bac de tête permettant alors de soutirer le produit au bouilleur. Une étude de faisabilité basée sur l’analyse des diagrammes de composition de colonne montre que le procédé permet d’obtenir un produit pur à 95% en EDA si le tiers corps est alimenté à un point intermédiaire de la colonne. Les étapes opératoires de la séparation sont : 1/ remplissage (F/L’=0 ; s=∞); 2/ nettoyage (F/L’>0 ; s=∞); 3/ production EDA (F/L’>0 ; s<∞) ; 4/ coupe intermédiaire ; production W et régénération MeOH (F/L’=0 ; s<∞). Un bon rendement (~80% en EDA) est atteint par simulation rigoureuse, ProsimBatc

Feasibility of extractive distillation process variants in batch rectifier column

A systematic comparison is presented about the separation tasks of azeotropic and close-boiling mixtures applying batch extractive distillation (BED) in rectifier. All the eight possible mixture types with at most a single azeotrope (minimum and maximum boiling azeotropes with heavy, light, and intermediate boiling entrainers; and close boiling mixtures with heavy and light entrainers) are compared. The main results of the feasibility studies on the hitherto unpublished cases are presented. All the cases are feasible in batch rectifier, applying BED. The operation steps are determined by the relative position of the azeotropic composition and entrainer in bubble point ranking. The main limiting parameters (F/V, N, Epremix) are also determined by the mentioned relative position; only the existence of maximum number of stages in the rectifying section is determined by the type of the azeotrope. Use of residue curves maps (RCMs) for predicting feasibility is not generally satisfactory, but profiles maps can be used instead. Studying only the total reflux case can be misleading, and should be treated with great care. The theoretical results of separation variants applying intermediate boiling entrainer were proved experimentally

Distillation extractive discontinue dans une colonne de rectification et dans une colonne inverse

This thesis deals with the systematic feasibility analysis of the separation of minimum-boiling azeotropes, maximum-boiling azeotropes and the low relativ voltatility mixtures in batch extractive distillation in a rectifier and in a stripper. Light, intermediate and heavy entrainers are applied in each case to realise the separation. Moreover, batch heterogeneous extractive distillation with heavy entrainer is studied here. General feasibility methodology is developped for the rectifier and for the stripper presented in organigrammes. Summarized tables show all the results provided by the feasibility analysis, namely, the feasibility conditions, the limiting operational parameters and the separation sequence. The main results of the feasibility analysis are justified by simulations and experimentsTOULOUSE-ENSIACET (315552325) / SudocSudocFranceF