Molecular modeling for physical property prediction

Multiscale modeling is becoming the standard approach for process study in a broader framework that promotes computer aided integrated product and process design. In addition to usual purity requirements, end products must meet new constraints in terms of environmental impact, safety of goods and people, specific properties. This chapter adresses the use of molecular modeling tools for the prediction of physical property usefull for chemical engineering practice

Preface

This special issue contains selected papers from the 18th European Symposium of Computer Aided Process Engineering (ESCAPE-18) which took place in Lyon, France, 1–4 June 2008. ESCAPE-18 was the 667th event of the European Federation of Chemical Engineering (EFCE) under responsibility of its CAPE Working Party. CAPE refers to computer aided methods, algorithms and techniques related to process and product engineering. The ESCAPE series brings the latest innovations and achievements by leading professionals from the industrial and academic communities. It serves as a forum for engineers, scientists, researchers, managers and students from academia and industry to present and discuss progress being made in the area of CAPE

New double column system for heteroazeotropic batch distillation

A new double column system (DCS) operated in closed mode is suggested for heterogeneous batch distillation. This configuration is investigated by feasibility studies based on the assumption of maximal separation and is compared with the traditional batch rectifier (BR). We study the configurations also by dynamic simulation based on a detailed model using a professional simulator. For the new configuration the minimal duration of the process is determined. The influence of the most important operational parameters is studied. The calculations and the simulations are performed for a binary (n-butanol–water) and for a ternary heteroazeotropic mixture (isopropanol–water + benzene as entrainer). One of the advantages of the DCS is that distillation of binary and ternary systems is performed in only one step. Furthermore the recovery of components is usually higher and the amount of byproducts is lower

REGSOLexpert: Entrainer Selection Tool for waste solvent recovery by batch distillation processes

A general procedure to systematize the search of several alternatives enabling the separation of non-ideal binary mixtures such as pressure-swing distillation, azeotropic and extractive distillation is presented. The use of heterogeneous entrainers is specially highlighted

Heterogeneous batch distillation processes for waste solvent recovery in pharmaceutical industry

A summary about our experiences in the introduction of heterogeneous entrainers in azeotropic and extractive batch distillation is presented in this work. Essential advantages of the application of heterogeneous entrainers are showed by rigorous simulation and experimental verification in a bench batch distillation column for separating several azeotropic mixtures such as acetonitrile – water, n hexane – ethyl acetate and chloroform – methanol, commonly found in pharmaceutical industry

Optimisation of heterogeneous batch extractive distillation

This paper considers the optimisation of batch extractive distillation, using heterogeneous entrainers for the first time. The objective function includes the maximum of overall profit and the optimisation variables are the entrainer flowrate and the reflux ratio that is an optimal combination of both decanted phases. Simulation and optimization is performed within MATLAB, by using a genetic algorithm coupled to a short-cut model of the distillation column. The performance of the optimisation scheme is illustrated through the separation of chloroform – methanol mixture with water considering either a constant or a piecewise constant policy for both optimization variables

Numerical and Computational Strategy for Pressure-Driven Steady-State Simulation of Oilfield Production

Within the TINA (Transient Integrated Network Analysis) research project and in partnership with Total, IFP is developing a new generation of simulation tool for flow assurance studies. This integrated simulation software will be able to perform multiphase simulations from the wellbore to the surface facilities. The purpose of this paper is to define, in a CAPE-OPEN compliant environment, a numerical and computational strategy for solving pressure-driven steady-state simulation problems, i.e. pure simulation and design problems, in the specific context of hydrocarbon production and transport from the wellbore to the surface facilities

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

Batch heteroazeotropic distillation in a new Generalised Double-Column System

We study the separation of the minimum homoazeotrope isopropanol - water by applying cyclohexane and n-hexane as entrainer in a new Generalised Double-Column batch heteroazeotropic distillation System (GDCS). First its feasibility is studied by a simplified method then we do sensitivity analysis by rigorous simulation. The minimum duration is determined for the GDCS and for the original DCS, and their performances are compared. Due to its higher number of degrees of freedom the GDCS provides a more flexible operation than the DCS. In each case we obtained shorter process durations and lower energy demands by the GDCS than by the DCS

Modular simulation and optimization of an 12MW industrial gasifier

In this work, a flexible model, built from elementary modules, is developed for an industrial waste gasification process, in an industrial moving bed reactor located in Morcenx (France). This gasifier is able to treat more than 46,875 ton/year of RDF (Refused Derived Fuel) waste for producing 12 MW. Drying, pyrolysis, combustion / gasification and plasma polishing are used to convert waste directly into a synthesis gas composed of carbon monoxide and hydrogen. This synthesis gas is then used for producing electricity via gas engine