Modern Drying Technology E-Book

• Herausgeber: Wiley-VCH
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 634

Veröffentlichungsjahr: 2011

Beschreibung

This five-volume series provides a comprehensive overview of all important aspects of modern drying technology, concentrating on the transfer of cutting-edge research results to industrial use. Volume 4 deals with the reduction of energy demand in various drying processes and areas, highlighting the following topics: Energy analysis of dryers, efficient solid-liquid separation techniques, osmotic dehydration, heat pump assisted drying, zeolite usage, solar drying, drying and heat treatment for solid wood and other biomass sources, and sludge thermal processing.

Leseprobe

Contents

Cover

Modern Drying Technology

Title Page

Copyright

Series Preface

Preface of Volume 4

List of Contributors

Recommended Notation

EFCE Working Party on Drying; Address List

Chapter 1: Fundamentals of Energy Analysis of Dryers

1.1 Introduction

1.2 Energy in Industrial Drying

1.3 Fundamentals of Dryer Energy Usage

1.4 Setting Targets for Energy Reduction

1.5 Classification of Energy Reduction Methods

1.6 Case Study

1.7 Conclusions

References

Chapter 2: Mechanical Solid–Liquid Separation Processes and Techniques

2.1 Introduction and Overview

2.2 Density Separation Processes

2.3 Filtration

2.4 Enhancement of Separation Processes by Additional Electric or Magnetic Forces

2.5 Mechanical/Thermal Hybrid Processes

2.6 Important Aspects of Efficient Solid–Liquid Separation Processes

2.7 Conclusions

References

Chapter 3: Energy Considerations in Osmotic Dehydration

3.1 Scope

3.2 Introduction

3.3 Mass Transfer Kinetics

3.4 Modeling of Osmotic Dehydration

3.5 Osmotic Dehydration – Two Major Issues

3.6 Conclusions

3.7 Additional Notation Used in Chapter 3

References

Chapter 4: Heat Pump Assisted Drying Technology – Overview with Focus on Energy, Environment and Product Quality

4.1 Introduction

4.2 Heat Pump Drying System – Fundamentals

4.3 Various Configurations/Layout of a HPD

4.4 Heat Pumps – Diverse Options and Advances

4.5 Miscellaneous Heat Pump Drying Systems

4.6 Applications of Heat Pump Drying

4.7 Sizing of Heat Pump Dryer Components

4.8 Future Research and Development Needs in Heat Pump Drying

References

Chapter 5: Zeolites for Reducing Drying Energy Usage

5.1 Introduction

5.2 Zeolite as an Adsorption Material

5.3 Using Zeolites in Drying Systems

5.4 Energy Efficiency and Heat Recovery

5.5 Realization of Adsorption Dryer Systems

5.6 Cases

5.7 Economic Considerations

5.8 Perspectives

Appendix 5.A: Sorption Isotherm Data

Acknowledgment

References

Chapter 6: Solar Drying

6.1 Introduction

6.2 Solar Radiation

6.3 Solar Air Heaters

6.4 Design and Function of Solar Dryers

6.5 Solar Drying Kinetics

6.6 Control Strategies for Solar Dryers

6.7 Economic Feasibility of Solar Drying

6.8 Conclusions and Outlook

6.9 Additional Notation Used in Chapter 6

Greek Letters

Subscripts

Abbreviations

References

Chapter 7: Energy Issues of Drying and Heat Treatment for Solid Wood and Other Biomass Sources

7.1 Introduction

7.2 Wood and Biomass as a Source of Renewable Material and Energy

7.3 Energy Consumption and Energy Savings in the Drying of Solid Wood

7.4 Preconditioning of Biomass as a Source of Energy: Drying and Heat Treatment

7.5 Conclusions

Acknowledgements

Additional Notation Used in Chapter 7

Abbreviations

References

Chapter 8: Efficient Sludge Thermal Processing: From Drying to Thermal Valorization

8.1 Introduction to the Sludge Context

8.2 Sludge Drying Technologies

8.3 Energy Efficiency of Sludge Drying Processes

8.4 Thermal Valorization of Sewage Sludge

8.5 Energy Efficiency of Thermal Valorization Routes

8.6 Conclusions

8.7 Additional Notation Used in Chapter 8

8.19 Subscripts and Superscripts

8.8 Abbreviations

References

Index

Modern Drying Technology

Edited by E. Tsotsas and A. Mujumdar

Other Volumes

Volume 1: Computational Tools at Different Scales

ISBN: 978-3-527-31556-7

Volume 2: Experimental Techniques

ISBN: 978-3-527-31557-4

Volume 3: Product Quality and Formulation

ISBN: 978-3-527-31558-1

Forthcoming Volumes

Volume 5: Process Intensification

ISBN: 978-3-527-31560-4

Modern Drying Technology Set (Volumes 1 – 5)

ISBN: 978-3-527-31554-3

Modern Drying Technology

All books published by Wiley-VCH are carefully produced. Nevertheless, authors, editors, and publisher do not warrant the information contained in these books, including this book, to be free of errors. Readers are advised to keep in mind that statements, data, illustrations, procedural details or other items may inadvertently be inaccurate.

Library of Congress Card No.: applied for

British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library.

Bibliographic information published by the Deutsche Nationalbibliothek The Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data are available on the Internet at http://dnb.d-nb.de.

© 2012 Wiley-VCH Verlag & Co. KGaA, Boschstr. 12, 69469 Weinheim, Germany

All rights reserved (including those of translation into other languages). No part of this book may be reproduced in any form – by photoprinting, microfilm, or any other means – nor transmitted or translated into a machine language without written permission from the publishers. Registered names, trademarks, etc. used in this book, even when not specifically marked as such, are not to be considered unprotected by law.

Composition Thomson Digital, Noida, India

Printing and Binding Strauss GmbH, Mörlenbach

Cover Design Adam Design, Weinheim

Print ISBN: 978-3-527-31559-8

ePDF ISBN: 978-3-527-63169-8

oBook ISBN: 978-3-527-63168-1

Series Preface

The present series is dedicated to drying, that is, to the process of removing moisture from solids. Drying has been conducted empirically since the dawn of the human race. In traditional scientific terms it is a unit operation in chemical engineering. The reason for the continuing interest in drying and, hence, the motivation for the series concerns the challenges and opportunities. A permanent challenge is connected to the sheer amount and value of products that must be dried – either to attain their functionalities, or because moisture would damage the material during subsequent processing and storage, or simply because customers are not willing to pay for water. This comprises almost every material used in solid form, from foods to pharmaceuticals, from minerals to detergents, from polymers to paper. Raw materials and commodities with a low price per kilogram, but with extremely high production rates, and also highly formulated, rather rare but very expensive specialties have to be dried.

This permanent demand is accompanied by the challenge of sustainable development providing welfare, or at least a decent living standard, to a still-growing humanity. On the other hand, opportunities emerge for drying, as well as for any other aspect of science or living, from either the incremental or disruptive development of available tools. This duality is reflected in the structure of the book series, which is planned for five volumes in total, namely:

Volume 1: Computational tools at different scales

Volume 2: Experimental techniques

Volume 3: Product quality and formulation

Volume 4: Energy savings

Volume 5: Process intensification

As the titles indicate, we start with the opportunities in terms of modern computational and experimental tools in Volumes 1 and 2, respectively. How these opportunities can be used in fulfilling the challenges, in creating better and new products, in reducing the consumption of energy, in significantly improving existing or introducing new processes will be discussed in Volumes 3, 4 and 5. In this sense, the first two volumes of the series will be driven by science; the last three will try to show how engineering science and technology can be translated into progress.

In total, the series is designed to have both common aspects with and essential differences from an extended textbook or a handbook. Textbooks and handbooks usually refer to well-established knowledge, prepared and organized either for learning or for application in practice, respectively. On the contrary, the ambition of the present series is to move at the frontier of “modern drying technology”, describing things that have recently emerged, mapping things that are about to emerge, and also anticipating some things that may or should emerge in the near future. Consequently, the series is much closer to research than textbooks or handbooks can be. On the other hand, it was never intended as an anthology of research papers or keynotes – this segment being well covered by periodicals and conference proceedings. Therefore, our continuing effort will be to stay as close as possible to a textbook in terms of understandable presentation, and as close as possible to a handbook in terms of applicability.

Another feature in common with an extended textbook or a handbook is the rather complete coverage of the topic by the entire series. Certainly, not every volume or chapter will be equally interesting for every reader, but we do hope that several chapters and volumes will be of value for graduate students, for researchers who are young in age or thinking, and for practitioners from industries that are manufacturing or using drying equipment. We also hope that the readers and owners of the entire series will have a comprehensive access not to all, but to many significant recent advances in drying science and technology. Such readers will quickly realize that modern drying technology is quite interdisciplinary, profiting greatly from other branches of engineering and science. In the opposite direction, not only chemical engineers, but also people from food, mechanical, environmental or medical engineering, material science, applied chemistry or physics, computing and mathematics may find one or the other interesting and useful results or ideas in the series.

The mentioned interdisciplinary approach implies that drying experts are keen to abandon the traditional chemical engineering concept of unit operations for the sake of a less rigid and more creative canon. However, they have difficulties of identification with just one of the two new major trends in chemical engineering, namely process-systems engineering or product engineering. Efficient drying can be completely valueless in a process system that is not efficiently tuned as a whole, while efficient processing is certainly valueless if it does not fulfill the demands of the market (the customer) regarding the properties of the product. There are few topics more appropriate in order to demonstrate the necessity of simultaneous treatment of product and process quality than drying. The series will try to work out chances that emerge from this crossroads position.

One further objective is to motivate readers in putting together modules (chapters from different volumes) relevant to their interests, creating in this manner individual, task-oriented threads through the series. An example of one such thematic thread set by the editors refers to simultaneous particle formation and drying, with a focus on spray fluidized beds. From the point of view of process-systems engineering, this is process integration – several “unit operations” take place in the same equipment. On the other hand, it is product engineering, creating structures – in many cases nanostructures – that correlate with the desired application properties. Such properties are distributed over the ensemble (population) of particles, so that it is necessary to discuss mathematical methods (population balances) and numerical tools able to resolve the respective distributions in one chapter of Volume 1. Measuring techniques providing access to properties and states of the particle system will be treated in one chapter of Volume 2. In Volume 3, we will attempt to combine the previously introduced theoretical and experimental tools with the goal of product design. Finally, important issues of energy consumption and process intensification will appear in chapters of Volumes 4 and 5. Our hope is that some thematic combinations we have not even thought about in our choice of contents will arise in a similar way.

As the present series is a series of edited books, it cannot be as uniform in either writing style or notation as good textbooks are. In the case of notation, a list of symbols has been developed and will be printed at the beginning of every volume. This list is not rigid but foresees options, at least partially accounting for the habits in different parts of the world. It has been recently adopted as a recommendation by the Working Party on Drying of the European Federation of Chemical Engineering (EFCE). However, the opportunity of placing short lists of additional or deviant symbols at the end of every chapter has been given to all authors. The symbols used are also explained in the text of every chapter, so that we do not expect any serious difficulties in reading and understanding.

The above indicates that the clear priority in the edited series was not in uniformity of style, but in the quality of the contents that are very close to current international research from academia and, where possible, also from industry. Not every potentially interesting topic is included in the series, and not every excellent researcher working on drying contributes to it. However, we are very confident about the excellence of all research groups that we were able to gather together, and we are very grateful for the good cooperation with all chapter authors. The quality of the series as a whole is set mainly by them; the success of the series will primarily be theirs. We would also like to express our acknowledgements to the team of Wiley-VCH who have done a great job in supporting the series from the first idea to realization. Furthermore, our thanks go to Mrs Nicolle Degen for her additional work, and to our families for their tolerance and continuing support.

Last but not least, we are grateful to the members of the Working Party on Drying of the EFCE for various reasons. First, the idea for the series came up during the annual technical and business meeting of the working party 2005 in Paris. Secondly, many chapter authors could be recruited among its members. Finally, the Working Party continues to serve as a panel for discussion, checking and readjustment of our conceptions about the series. The list of the members of the working party with their affiliations is included in every volume of the series in the sense of acknowledgment, but also in order to promote networking and to provide access to national working parties, groups and individuals. The present edited books are complementary to the regular activities of the EFCE Working Party on Drying, as they are also complementary to various other regular activities of the international drying community, including well-known periodicals, handbooks, and the International Drying Symposia.

December 2006

Evangelos TsotsasArun S. Mujumdar

Preface of Volume 4

As already stressed in the general preface, the contents of modern drying technology are subjected to the dual requirement of producing high-quality products with highly efficient processes. Moreover, drying is energetically expensive – a major consumer of energy in modern societies – which makes energy use a crucial aspect of process efficiency. In times of abundant and inexpensive energy, one might ignore – and many people did – the respective consumption, concluding that any drying process is a good process as long as the desired product properties can be preserved or established. However, cheap energy seems to belong to history, and serious environmental concerns have appeared, related to climate change. Consequently, modern drying technology must address the complete challenge, regarding product quality and process efficiency as the two faces of the same coin, and treat them concurrently. Having discussed “Product quality and formulation” in Volume 3 of this series, we turn our attention to “Energy savings” in Volume 4. The optimistic title should by no means conceal difficulties arising from thermodynamic and economic restraints, but it does express our confidence that modern drying technology can fulfill the task. This confidence stems from a number of available methods, emerging approaches and innovative ideas, which can seriously serve and significantly contribute to the ultimate goal of energetically efficient drying processes, as presented in the following eight chapters:

Chapter 1: Fundamentals of energy analysis of dryers

Chapter 2: Mechanical solid-liquid separation processes and techniques

Chapter 3: Energy considerations in osmotic dehydration

Chapter 4: Heat pump assisted drying technology – Overview with focus on energy, environment and product quality

Chapter 5: Zeolites for reducing drying energy usage

Chapter 6: Solar drying

Chapter 7: Energy issues of drying and heat treatment for solid wood and other biomass sources

Chapter 8: Efficient sludge thermal processing: From drying to thermal valorization

Chapter 1 sets the fundamentals of energy analysis, breaking down the total energy consumption of a dryer in its constituent parts, defining efficiency, and identifying sources and reasons for inefficiency and losses. Pinch analysis is discussed in detail as a powerful tool for assessing the potential of and designing heat transfer from hot to cold material streams. Various other methods that can lead to energy savings are classified and presented – from altering operating conditions to the combination of heat and power. Specific examples that range from learning exercises to industrial case studies are used to put figures and numbers behind the principles. Most important, Chapter 1 points out very clearly that dryer energy savings should always be considered in the context of the overall process or even production cite, in a systemic approach.

An evident systemic aspect is that the energy consumption of any dryer decreases with decreasing moisture content in the feed. Unfortunately, the respective potential for energy savings is not always fully utilized, because thermal drying and the preceding solid-liquid separation are designed separately, often by different people. Therefore, solid-liquid separation processes are highlighted in Chapter 2, including an exhaustive taxonomy, the detailed presentation of equipment, and criteria for selection and design. Modern techniques for the enhancement of such separations by electric or magnetic forces are presented. Furthermore, improvements that can be attained by the consecutive, parallel or combined use of equipment are discussed, referring to both purely mechanical steps and to the combination of mechanical separation with thermal drying in the batch or continuous mode of operation.

Another possibility to remove water out of soft materials previously to drying, namely osmosis, is treated in Chapter 3. Osmotic dehydration is relevant to food processing and can lead to significant energy savings in the drying step, but it has also an impact on food quality, which must be simultaneously considered. Experiences with and benefits from the combination of osmotic dehydration with different kinds of thermal drying are comprehensively reviewed.

One major source of energy loss from conventional one-pass hot-air dryers is “over the chimney”. Therefore, heat recovery from the warm and moist exhaust air is a key to the enhancement of the energetic efficiency of dryers. Since such recovery can be achieved by heat pumps, heat pump drying is discussed in detail in Chapter 4. A distinctive advantage of this technology lies in its add-on character – it can be applied to virtually any kind of dryer, though it is most reasonable in combination with low to moderate temperature dryers for the processing of sensible goods. Chapter 4 explains the principles of different types of heat pumps, presents various methods for their combination with dryers, and quantifies the merits that can be obtained in terms of improved energetic efficiency. Extensive records of successful application to various products – food and agricultural, wood and timber, pharmaceutical and biological – are presented, design methods are discussed, and opportunities for future development are outlined.

Similarly to heat pumps, particulate adsorbents – especially zeolites – can also be used for heat recovery from dryer exhaust gases. Zeolite drying is highlighted as a powerful and promising technology in Chapter 5. It is pointed out that zeolites can be used for heat recovery from the exhaust, but they can also serve the purpose of inlet air dehumidification, or even be mixed to and subsequently separated from the drying material. The resulting energy savings are evaluated in a systematic way, starting with simple configurations and moving step-by-step to more complex multi-stage or steam-operated systems. Examples of already realized facilities for the drying of dairy products, sludge and seeds are presented. Finally, economic aspects are analyzed in terms of pay-back times for the necessary additional investment.

In Chapter 6, solar drying is treated as a further energetically promising alternative. Solar energy is for free, but reaches the Earth with a relatively low flux and a strongly fluctuating rate. To use it for drying, solar energy must be harvested in an efficient way that does not require too much additional investment. This leads to special constructions of solar collectors and dryers, which are classified and discussed in detail. Applications of such equipment are presented for various agricultural products, and the necessity for relaxing the influence of variable energy input by appropriate control strategies is stressed. Case studies on timber and tobacco are used to show that solar drying can be economically viable and beneficial in comparison to both, primitive sun drying but also conventional hot-air drying.

It is well known that the harvesting of solar energy is very efficiently carried out by plants, creating biomass. Some kinds of biomass, namely wood, can be used to, for example, make furniture, some others as renewable fuels. Since both applications are closely related to drying and of a very large scale, they are discussed thoroughly in Chapter 7. First, benchmarks are provided for the energy demand of wood drying kilns, and methods for saving energy by improved kiln design and operation are presented. It is, then, shown, that preconditioning by drying can enhance the efficiency of processes aiming at the energetic valorization of biomass, such as combustion or gasification. Various drying technologies for fuel biomass are discussed. Dual-scale models applicable to the drying of both, timber pieces and fuel biomass particles are presented. Apart from the assessment of energetic efficiency, such models can also track product quality in terms of, for example, timber distortion or uniformity of residual moisture in a fuel biomass particle system.

Finally, Chapter 8 addresses the energetic issues of one more large-scale application of drying, namely the drying of sludge from wastewater treatment facilities. The case is similar to woody biomass, because the main component of sludge is bacterial biomass that may just need to be dried before, for example, landfill, or may require drying in combination with subsequent processes of thermal valorization, such as – again – combustion or gasification. After a presentation of sludge composition and properties, the various types of drying equipment and processes that can be used for sludge are discussed thoroughly, along with their energetic efficiency. Specific case studies illustrate that the proper integration of drying in municipal wastewater treatment plants can significantly reduce the energy demand, and that sludge can have a significant value as a fuel, if efficiently pre-dried.

Due to nature of the topic, the present volume of Modern Drying Technology has interdisciplinary links to thermodynamics, energy and environmental engineering, process systems engineering, food engineering, meteorology, forestry, biology and biotechnology, but also to economics. Concerning the scale, single particles and processing equipment (particle systems) are considered, but also entire production sites and global environmental and economic systems.

Thematic threads within the Modern Drying Technology series exist from the present:

- Chapter 1 to Chapter 7 of Vol. 1 (systems engineering)

- Chapters 2 and 5 to Chapter 6 of Vol. 2 (particle characterization)

- Chapters 3 and 4 to Chapters 1 and 2 of Vol. 3 (food processing)

- Chapter 7 to Chapter 1 of Vol. 1 (wood drying)

- Chapter 8 to Chapters 4 of Vol. 2 and Chapter 5 of Vol. 3 (gel materials)

Additionally, the entire present volume is closely related to Vol. 3, as the already mentioned two faces of the same coin. The overall message is that of drying science and technology in good shape for doing exactly what the title of the volume describes, namely saving energy.

Acknowledgements for Volume 4 are the same as in the series preface, we would like to stress them by reference, but not repeat them here.

August 2011

Evangelos TsotsasArun S. Mujumdar

List of Contributors

Editors

Prof. Evangelos Tsotsas Otto von Guericke University Magdeburg Thermal Process Engineering PSF 4120 39106 Magdeburg Germany Email: [email protected]

Prof. Arun S. Mujumdar National University of Singapore Mechanical Engineering Block EA 07-0 9 Engineering Drive 1 Singapore 117576 Singapore Email: [email protected]

Authors

Dr. Giana Almeida AgroParisTech 1 avenue des Olympiades 91744 Massy cedex France Email: [email protected]

Dr. Harald Anlauf Karlsruhe Institute of Technology (KIT) Institute of Mechanical Process Engineering and Mechanics (MVM) Straße am Forum 8 76131 Karlsruhe Germany Email: [email protected]

Dr. Patricia Arlabosse Université de Toulouse Mines Albi, CNRS Campus Jarlard 81013 Albi France Email: [email protected]

Dr. Moniek A. Boon TNO Postbus 360 3700 AJ Zeist The Netherlands Email: [email protected]

Dr. Paul J. Th. Bussmann TNO Postbus 360 3700 AJ Zeist The Netherlands Email: [email protected]

Dr. Julien Colin AgroParisTech ENGREF 14 rue Girardet 54 042 Nancy France Email: [email protected]

Prof. Michel Crine University of Liége Department of Applied Chemistry Laboratory of Chemical Engineering Bâtiment B6c – Sart-Tilman 4000 Liége Belgium Email: [email protected]

Dr. Yohann Dumont Aix-Marseille Université M2P2, UMR CNRS 6181 Europôle de l'Arbois, BP 80 13545 Aix en Provence Cedex 4 France Email: [email protected]

Dr. Jean-Henry Ferrasse Aix-Marseille Université M2P2, UMR CNRS 6181 Europôle de l'Arbois, BP 80 13545 Aix en Provence Cedex 4 France Email: jean-henry.ferrasse@etu. univ-cezanne.fr

Dr. Sachin V. Jangam National University of Singapore Mechanical Engineering Department Blk EA, #06-15 9 Engineering Drive 1 Singapore 117576 Singapore Email: [email protected]

Ir. Ian C. Kemp Glaxo Smithkline, R&D Gunnels Wood Road Stevenage SG1 2NY United Kingdom Email: [email protected]

Prof. Didier Lecomte Université de Toulouse Mines Albi, CNRS Centre RAPSODEE Campus Jarlard 81013 Albi France Email: [email protected]

Prof. Angélique Léonard University of Liège Department of Applied Chemistry Laboratory of Chemical Engineering Bâtiment B6a – Sart-Tilman 4000 Liège Belgium Email: [email protected]

Prof. Werner Mühlbauer Universität Hohenheim Institute of Agricultural Engineering Garbenstrasse 9 70593 Stuttgart Germany Email: [email protected]

Prof. Arun S. Mujumdar National University of Singapore Mechanical Engineering Department Blk EA, #06-15 9 Engineering Drive 1 Singapore 117576 Singapore Email: [email protected]

Prof. Joachim Müller Universität Hohenheim Institute of Agricultural Engineering Garbenstrasse 9 70593 Stuttgart Germany Email: [email protected]

Prof. Patrick Perré Ecole Centrale Paris Grande Voie des Vignes 92295 Châtenay-Malabry France Email: [email protected]

Prof. Hosahalli S. Ramaswamy McGill University Department of Food Science Macdonald Campus 21111 Lakeshore Road Ste-Anne-de-Bellevue PQ H9X 3V9 Canada Email: [email protected]

Dr. Yetenayet Bekele Tola McGill University Department of Food Science Macdonald Campus 21111 Lakeshore Road Ste-Anne-de-Bellevue PQ H9X 3V9 Canada Email: [email protected]

Dr. Antonius J.B. van Boxtel Wageningen UR Department of Agrotechnology and Food Sciences Systems and Control Group Postbus 17 6700 AA Wageningen The Netherlands Email: [email protected]

Ir. Henk C. van Deventer TNO Postbus 360 3700 AJ Zeist The Netherlands Email: [email protected]

EFCE Working Party on Drying: Address List

Prof. Odilio Alves-Filho Norwegian University of Science and Technology Department of Energy and Process Engineering Kolbjørn Hejes vei 1B 7491 Trondheim [email protected]

Prof. Julien Andrieu(delegate) UCB Lyon I/ESCPE LAGEP UMR CNRS 5007 batiment 308 G 43 boulevard du 11 novembre 1918 69622 Villeurbanne cedex [email protected]

Dr. Paul Avontuur Glaxo Smith Kline New Frontiers Science Park H89 Harlow CM19 5AW United [email protected]

Prof. Christopher G. J. Baker Drying Associates Harwell International Business Centre 404/13 Harwell Didcot Oxfordshire OX11 ORA United [email protected]

Prof. Antonello Barresi(delegate) Politecnico di Torino Dip. Scienza dei Materiali e Ingegneria Chimica Corso Duca degli Abruzzi 24 10129 Torino [email protected]

Dr. Rainer Bellinghausen(delegate) Bayer Technology Services GmbH BTS-PT-PT-PDSP Building E 41 51368 Leverkusen [email protected]

Dr. Carl-Gustav Berg Abo Akademi Process Design Laboratory Biskopsgatan 8 20500 Abo [email protected]

Dr. Catherine Bonazzi(delegate) AgroParisTech – INRA JRU for Food Process Engineering 1 Avenue des Olympiades 91744 Massy cedex [email protected]

Paul Deckers M.Sc.(delegate) Bodec Process Optimization and Development Industrial Area ’t Zand Bedrijfsweg 1 5683 CM Best The [email protected]

Prof. Stephan Ditchev University of Food Technology 26 Maritza Blvd. 4002 Plovdiv [email protected]

Dr. German I. Efremov Pavla Korchagina 22 129278 Moscow [email protected]

Prof. Trygve Eikevik Norwegian University of Science and Technology Dep. of Energy and Process Engineering Kolbjørn Hejes vei 1B 7491 Trondheim [email protected]

Dr. Ioannis Evripidis Dow Deutschland GmbH & Co. OHG P.O. Box 1120 21677 Stade [email protected]

Prof. Istvan Farkas(delegate) Szent Istvan University Department of Physics and Process Control Pater K. U. 1. 2103 Godollo [email protected]

Dr. Dietrich Gehrmann Wilhelm-Hastrich-Str. 12 51381 Leverkusen [email protected]

Prof. Adrian-Gabriel Ghiaus(delegate) Thermal Engineering Department Technical University of Civil Engineering Bd. P. Protopopescu 66 021414 Bucharest [email protected]

Prof. Gheorghita Jinescu University “Politehnica” din Bucuresti Faculty of Industrial Chemistry, Department of Chemical Engineering 1, Polizu street Building F, Room F210 78126 Bucharest [email protected]

Prof. Gligor Kanevce St. Kliment Ohridski University Faculty of Technical Sciences ul. Ivo Ribar Lola b.b. Bitola [email protected]

Prof. Markku Karlsson(delegate) UPM-Kymmene Corporation P.O. Box 380 00101 Helsinki [email protected]

Ir. Ian C. Kemp(delegate) Glaxo SmithKline, R&D Gunnels Wood Road Stevenage SG1 2NY United [email protected]

Prof. P. J. A. M. Kerkhof Eindhoven University of Technology Dept. of Chemical Engineering P.O. Box 513 5600 MB Eindhoven The [email protected]

Prof. Matthias Kind Universität Karlsruhe (TH) Institute für Thermische Verfahrenstechnik Kaiserstr. 12 76128 Karlsruhe [email protected]

Prof. Eli Korin Ben-Gurion University of the Negev Chemical Engineering Department Beer-Sheva 84105 [email protected]

Prof. Ram Lavie Department of Chemical Engineering Technion – Israel Institute of Technolgy Technion City Haifa 32000 [email protected]

Prof. Angélique Léonard (delegate) Laboratoire de Génie Chimique Département de Chimie Appliquée Université de Liège Bâtiment B6c – Sart-Tilman 4000 Liège [email protected]

Prof. Avi Levy(delegate) Ben-Gurion University of the Negev Department of Mechanical Engineering Beer-Sheva 84105 [email protected]

Prof. Natalia Menshutina Mendeleyev University of Chemical Technology of Russia (MUCTR) High Technology Department 125047 Muisskaya sq.9 Moscow [email protected]

Jun.-Prof. Thomas Metzger Otto-von-Guericke University Thermal Process Engineering P.O. Box 4120 39016 Magdeburg [email protected]

Prof. Antonio Mulet Pons(delegate) Universitat Politecnica de Valencia Departament de Tecnologia d'Aliments Cami de Vera s/n 46071 Valencia [email protected]

Prof. Zdzislaw Pakowski(delegate) Technical University of Lodz Faculty of Process and Environmental Engineering ul. Wolczanska 213 93-005 Lodz [email protected]

Prof. Patrick Perré(delegate, chairman of WP) Ecole Centrale Paris Laboratoire de Génie des Procédés et Matériaux Grande Voie des Vignes 92295 Châtenay-Malabry [email protected]

Dr. Romain Rémond (WP secretary) Research Engineer AgroParisTech - Engref 14, Rue Girardet 54000 [email protected]

Dr. Roger Rentröm Karlstad University Department of Environmental and Energy Systems Universitetsgatan 2 65188 Karlstad [email protected]

Prof. Michel Roques Universite de Pau et des Pays de l'Adour 5 Rue Jules-Ferry ENSGTI 64000 Pau [email protected]

Dr. Carmen Rosselló(delegate) University of Illes Baleares Dep. Quimica Ctra. Valldemossa km 7.5 07122 Palme Mallorca [email protected]

Prof. G. D. Saravacos(delegate) Nea Tiryntha 21100 Nauplion [email protected]

Dr. Scarlatos Panayiotis (Panos) SusTchem Engineering LTD 144 3rd September Street 11251 Athens [email protected]

Dr. Michael Schönherr Research Manager Drying Process Engineering BASF Aktiengesellschaft GCT/T – L 540 67056 Ludwigshafen [email protected]

Dr. Milan Stakic Vina Institute for Nuclear Sciences Center NTI P.O. Box 522 11001 Belgrade [email protected]

Prof. Stig Stenstrom(delegate) Lund University Institute of Technology Department of Chemical Engineering P.O. Box 124 22100 Lund [email protected]

Prof. Ingvald Strommen(delegate) Norwegian University of Science and Technology Department of Energy and Process Engineering Kolbjørn Hejes vei 1b 7491 Trondheim [email protected]

Prof. Czeslaw Strumillo(delegate) Technical University of Lodz Faculty of Process and Environmental Engineering Lodz Technical University ul. Wolczanska 213 93-005 Lodz [email protected]

Prof. Radivoje Topic(delegate) University of Belgrade Faculty of Mechanical Engineering 27 Marta 80 11000 Beograd [email protected]

Prof. Dr.-Ing. Evangelos Tsotsas(delegate, immediate past chairman of WP) Otto-von-Guericke University Thermal Process Engineering P.O. Box 4120 39016 Magdeburg [email protected]

Dr. Henk C. van Deventer(delegate) TNO Quality of Life P.O. Box 342 7300 AH Apeldoorn The [email protected]

Michael Wahlberg M.Sc. Niro Gladsaxevej 305 2860 Soeborg [email protected]

Dr. Bertrand Woinet(delegate) SANOFI-CHIMIE, CDP Bâtiment 8600 31-33 quai armand Barbès 69683 Neuville sur Saône cedex [email protected]

Prof. Ireneusz Zbicinski Lodz Technical University Faculty of Process and Environmental Engineering ul. Wolczanska 213 93-005 Lodz [email protected]

Chapter 1

Fundamentals of Energy Analysis of Dryers

Ian C. Kemp

1.1 Introduction

Drying is a highly energy-intensive process, accounting for 10–20% of total industrial energy use in most developed countries. The main reason for this is the need to supply the latent heat of evaporation to remove the water or other solvent. There are thus clear incentives to reduce energy use in drying: to conserve finite resources of fossil fuels, to reduce carbon footprint and combat climate change, and to improve process economics, but it is a challenging task facing real thermodynamic barriers.