design reactive distillation

Designing Reactive Distillation ProcesseswithImprovedEfficiency economy, exergy loss and responsiveness Designing Reactive Distillation ProcesseswithImprovedEfficiency economy, exergy loss and responsiveness Proefschrift ter verkrijging van de graad van doctor aan de Technische Universiteit Delft, op gezag van de Rector Magnificus prof. dr. ir. J. T. Fokkema, voorzitter van het College voor Promoties, in het openbaar te verdedigen op maandag 14 november 2005 om 13:00 uur door Cristhian Pa´ul ALMEIDA-RIVERA Ingeniero Qu´ımico (Escuela Polit´ecnica Nacional, Ecuador) Scheikundig ingenieur geboren te Quito, Ecuador Dit proefschrift is goedgekeurd door de promotor: Prof. ir. J. Grievink Samenstelling promotiecommissie: Rector Magnificus Voorzitter Prof. ir. J. Grievink Technische Universiteit Delft, promotor Prof. dr. G. Frens Technische Universiteit Delft Prof. ir. G. J. Harmsen Technische Universiteit Delft/Shell Chemicals Prof. dr. F. Kapteijn Technische Universiteit Delft Prof. dr. ir. H. van den Berg Twente Universiteit dr. A. C. Dimian Universiteit van Amsterdam Prof. dr. ir. A. I. Stankiewicz Technische Universiteit Delft/DSM Prof. dr. ir. P. J. Jansens Technische Universiteit Delft (reserve lid) Copyright c  2005 by Cristhian P. Almeida-Rivera, Delft All rights reserved. No part of the material protected by this copyright notice may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording or by any information storage and retrieval system, without written permission from the author. An electronic version of this thesis is available at http://www.library.tudelft.nl Published by Cristhian P. Almeida-Rivera, Delft ISBN 9-090200-37-1 / 9789090200378 Keywords: process systems engineering, reactive distillation, conceptual process design, multiechelon design approach, life-span inspired design methodology, residue curve mapping, multilevel approach, dynamic optimization, singularity theory, dynamic simulation, non-equilibrium thermodynamics, ex- ergy, responsiveness Printed by PrintPartners Ipskamp in the Netherlands Dedicated to my daughter Luc ´ ıa and my wife Paty Contents 1 Introduction 1 1.1 A Changing Environment for the Chemical Process Industry 2 1.2 Reactive Distillation Potential 3 1.3 Significance of Conceptual Design in Process Systems Engineering 5 1.4 Scope of Research 9 1.5 Outline and Scientific Novelty of the Thesis 11 2 Fundamentals of Reactive Distillation 13 2.1 Introduction 14 2.2 One-stage Level: Physical and Chemical (non-) Equilibrium 16 2.3 Multi-stage Level: Combined Effect of Phase and Chemical Equilibrium 17 2.4 Multi-stage Level: Reactive Azeotropy 20 2.5 Non-equilibrium Conditions and Rate Processes 23 2.6 Distributed Level: Column Structures 26 2.7 Distributed Level: Hydrodynamics 29 2.8 Flowsheet Level: Units and Connectivities 30 2.9 Flowsheet Level: Steady-State Multiplicities 31 2.10 Summary of Design Decision Variables 38 3 Conceptual Design of Reactive Distillation Processes: A Review 41 3.1 Introduction 42 3.2 Graphical Methods 42 3.3 Optimization-Based Methods 61 3.4 Evolutionary/Heuristic Methods 65 3.5 Concluding Remarks 70 i Contents 4 A New Approach in the Conceptual Design of RD Processes 75 4.1 Introduction 76 4.2 Interactions between Process Development and Process Design 77 4.3 Structure of the Design Process 79 4.4 Life-Span Performance Criteria 82 4.5 Multiechelon Approach: The Framework of the Integrated Design Method- ology 84 4.6 Concluding Remarks 87 5 Feasibility Analysis and Sequencing: A Residue Curve Mapping Ap- proach 89 5.1 Introduction 90 5.2 Input-Output Information Flow 90 5.3 Residue Curve Mapping Technique 91 5.4 Feasibility Analysis: An RCM-Based Approach 95 5.5 Case Study: Synthesis of MTBE 97 5.6 Concluding Remarks 103 6 Spatial and Control Structure Design in Reactive Distillation 107 6.1 Multilevel Modeling 108 6.2 Simultaneous Optimization of Spatial and Control Structures in Reactive Distillation 115 6.3 Concluding Remarks 124 7 Steady and Dynamic Behavioral Analysis 127 7.1 Introduction 128 7.2 Steady-State Behavior 129 7.3 Dynamic Behavior 144 7.4 Concluding Remarks 152 ii Contents 8 A Design Approach Based on Irreversibility 155 8.1 Introduction 156 8.2 Generic Lumped Reactive Distillation Volume Element 158 8.3 Integration of Volume Elements to a Column Structure 168 8.4 Application 1. Steady-state Entropy Production Profile in a MTBE Re- active Distillation Column 178 8.5 Application 2. Bi-Objective Optimization of a MTBE Reactive Distilla- tion Column 181 8.6 Application 3. Tri-Objective Optimization of a MTBE Reactive Distil- lation Column: A Sensitivity-Based Approach 185 8.7 Comparison Between Classical and Green Designs 189 8.8 Concluding Remarks 191 9 Conclusions and Outlook 193 9.1 Introduction 194 9.2 Conclusions Regarding Specific Scientific Design Questions 194 9.3 Conclusions Regarding Goal-Oriented Questions 200 9.4 Scientific Novelty of this Work 201 9.5 Outlook and Further Research 205 A Model Description and D.O.F. Analysis of a RD Unit 209 A.1 Mathematical Models 209 A.2 Degree of Freedom Analysis 217 B Synthesis of MTBE: Features of the System 221 B.1 Motivation 221 B.2 Description of the System 222 B.3 Thermodynamic Model 224 B.4 Physical Properties, Reaction Equilibrium and Kinetics 224 References 230 Summary 247 iii Contents Sammenvatting 251 Acknowledgements 257 Publications 261 About the author 263 Index 265 List of Symbols 267 Colophon 277 iv [...]... of reactive and nonreactive sections in a RD column 55 3.2 Qualitative fingerprint of the design methods used in reactive distillation 72 4.1 Design problem statement in reactive distillation 81 4.2 Categories of information resulting from the design process in reactive distillation 82 5.1 Input-output information for the feasibility analysis phase ... chemical processing industry are identified Then the reactive distillation processing is introduced The generalities of this process together with its technical challenges in design and operation are addressed The scientific setting of conceptual design in process systems engineering, with an emphasis on the key challenges in the design of reactive distillation is addressed The scope of this thesis is... Stankiewicz and Moulijn, 2002) Among the proven intensified processes reactive distillation (RD) occupies a place of preference and it is this which is covered in the course of this thesis, coupled with an emphasis on RD conceptual design 8 Introduction 1.3.3 Key Challenges in the Design of Reactive Distillation Due to its highly complex nature, the RD design task is still a challenge for the PSE community The... conventionally referred to as hybrid and intensified units, respectively and are characterized by reduced costs and process complexity Reactive distillation is an example of such an operation 2 Introduction 1.2 Reactive Distillation Potential 1.2.1 Main Features and Successful Stories Reactive distillation is a hybrid operation that combines two of the key tasks in chemical engineering, reaction and separation The... steps of a generic design cycle, • Question 4 What is the domain knowledge required and which new building blocks are needed for process synthesis? • Question 5 What are the (performance) criteria that need to be considered from a life-span perspective when specifying a reactive distillation design problem? 10 Introduction • Question 6 What (new) methods and tools are needed for reactive distillation process... driven design: ideal reactor-separator train 68 3.8 Relation between conversion and reflux ratio 68 3.9 Procedure to estimate reactive zone height, reflux ratio and column diameter 69 2.1 3.5 v List of Figures 4.1 The design problem regarded as the combination of a design program and a development program 78 4.2 Overall design. .. performance criteria 83 4.4 Multiechelon design approach in the conceptual design of RD processes: tools and decisions 85 Multiechelon design approach in the conceptual design of RD processes: interstage flow of information 86 Schematic representation of a simple batch still for the experimental determination of (non-) reactive residue curves ... 103 5.9 Residue curve map and separation sequence for zone a in the synthesis of MTBE by reactive distillation 104 6.1 Representation of the overall design structure for a RD structure 110 6.2 Schematic representation of the generic lumped reactive distillation volume element (GLRDVE) 112 6.3 Schematic representation of the link... take into account the economic, sustainability and responsiveness/controllability performances of the design alternatives 1.4 Scope of Research During the course of this PhD thesis we deal with the design of grassroots reactive distillation processes At this high level of aggregation, the process design is far more comprehensive than for most of the industrial activities (e.g retrofit, debottlenecking... unit for the synthesis of methyl acetate 3 Schematic representation of the relevant spatial scales in reactive distillation 14 2.2 Representation of stoichiometric and reactive distillation lines 19 2.3 Graphical determination of reactive azeotropy 21 2.4 Phase diagram for methanol in the synthesis of MTBE expressed in terms of . Combination of reactive and nonreactive sections in a RD column 55 3.2 Qualitative fingerprint of the design methods used in reactive distillation 72 4.1 Design problem statement in reactive distillation. Designing Reactive Distillation ProcesseswithImprovedEfficiency economy, exergy loss and responsiveness Designing Reactive Distillation ProcesseswithImprovedEfficiency economy,. Spatial and Control Structure Design in Reactive Distillation 107 6.1 Multilevel Modeling 108 6.2 Simultaneous Optimization of Spatial and Control Structures in Reactive Distillation 115 6.3 Concluding